“Someone once told me that time was a predator that stalked us all our lives. But I rather believe that time is a companion who goes with us on the journey and reminds us to cherish every moment because they'll never come again. What we leave behind is not as important as how we've lived.” -Brannon Braga, Ronald D. Moore, and Rick Berman
After being away for last weekend, it's time to take a look back at the past two weeks on Starts With A Bang! There's been no shortage of stories, of news, or of scientific matters of interest, so let's see what we've got:
- Is it foolishness to dream of terraforming Mars? (for Ask Ethan),
- Five eclipse sights you'll see better with a camera than your eyes (for Mostly Mute Monday),
- Was our Universe born in chaos? (by Paul Halpern, about the Mixmaster Universe),
- Did a 'Big Whack' create all of Pluto's moons?,
- 'Game of Thrones' home world could actually exist, says science,
- Eight other worlds in our Solar System might have life beyond Earth,
- Could the fabric of spacetime be defective? (for Ask Ethan),
- Sorry, internet, some of your favorite space pictures are fakes (for Mostly Mute Monday),
- Humanity needs science to survive and thrive,
- Heartland’s ‘6 Reasons To Be A Climate-Change Skeptic’ Are Six Demonstrable Lies,
- The sights, safety, and science of the great american eclipse, and
- If the Universe is expanding, then why aren't we? (by Sabine Hossenfelder, about spacetime).
Next week, I’ll be at two days of the official Star Trek convention in Las Vegas, on August 3rd and 4th, and the full schedule is now online! While the Perseids are coming up, followed by the total solar eclipse, there's still a whole lot to do before then. You've had a lot to think about and a lot to say, so let's get right into our comments of the week!
The particle tracks emanating from a high energy collision at the LHC in 2014. Although these collisions are plentiful and incredibly energetic, they have not yet yielded any compelling evidence of physics beyond the Standard Model. Image credit: Wikimedia Commons user Pcharito.
From Elle H.C. on a (non-)problem with the LHC: "...while the LHC is all about creating as much noise possible (luminosity)..."
Hang on. Are you contending that you can't know what goes on in a proton-proton collision, because there are bunched of protons being fired at each other, multiple collisions happening, and therefore we can't pull the signal out of the noise? Because although that certainly makes things more difficult, it's not at all a cause for concern in these experiments. Colliding composite particles means we need to be able to tell the difference between a collision of interest and a glancing collision, noise, or other particles that find their way (or their daughter particles find a way) into the detectors.
But we know how to do that: we trigger on large transverse-momentum events. For those events, we record the entirety of the data, and can determine which particle tracks originated from which collision. If you're not concerned with disrupting spacetime or creating a catastrophe at the LHC, then perhaps I've misunderstood what you've been contending for a long time.
From Pentcho Valev on walking the walk: "No need to ban me – I’m leaving your blog."
I'll believe it when I see it. Your "leaving my blog" lasted for an even shorter duration than a Jay-Z retirement.
Once you cross the threshold to form a black hole, everything inside the event horizon crunches down to a singularity that is, at most, one-dimensional. No 3D structures can survive intact. Image credit: Ask The Van / UIUC Physics Department.
From Adam on falling into a black hole with a tether: "I’m not getting the Option C listed here. If a particle emits a force mediating particle, and the force mediating particle crosses or goes deeper into an event horizon, even if it hits some other particle in some random location, how’s the original particle going to know?
Am I missing something obvious? Is a return force mediating particle not required?"
Imagine you're falling into a black hole. You know that once you cross the event horizon, nothing can get out. You also know that, with enough power, something that's outside the event horizon, if you do it just right, can escape. There are also tidal forces at play, working to stretch (in the "towards-the-singularity" direction) and compress (in the "perpendicular-to-that-previous-direction" direction) that you just can't avoid.
So what could possibly happen to you as you fall in? Or, if you prefer, as you, in your ship outside, try and deal with a tether that extends to an object that's just fallen inside the event horizon?
The outside part can try and escape! If you try too hard, you'll snap the tether. If you don't try hard enough, you'll be pulled in. And if you try just right -- which means just hard enough that if you tried any harder, the tether will snap -- then what? Well, the answer is that you'll fall in as slowly as possible. In particular, the particles outside will continue to communicate (i.e., exchange forces) with the particles outside; the particles inside will communicate with the particles inside; and the particles just inside the event horizon will exchange forces with the particles that were outside the event horizon when those virtual particles were emitted, but by time those signals are received, those particles now must be inside the event horizon. Which means you really do only have two options: either you'll be pulled in or the tether will snap. But you can continue to not have the tether snap if you fall in at the minimum possible rate, which is governed not by the material strength of the tether, but rather by the laws of relativity and causality. (And FYI, no, a "round-trip" force exchange isn't necessary. One way exerts forces on both particles. That's physics!)
From Denier on quantum gravity: "
Ethan: you are of the mindset that spacetime fabric is a thing, rather than nothingness itself. We can create visualizations of it; we can write down the laws that govern it; we can quantify the interrelationships of its various components. But it’s not a physical thing that you can poke holes in or tear apart
Denier: That sounds an awful lot like you’re declaring LQG to be fiction."
Hold on! Saying "spacetime is a fabric" is true in General Relativity, which is our theory of gravity today. Space and/or time may be quantized or discrete at a fundamental level, but those scales at which we'd observe such effects are Planck-scale effects, something we don't have any way of accessing with current or even envisioned future technology. LQG, or any discrete quantum theory of spacetime, could still be true, but it would have to reproduce classical GR in the low-energy limit.
I thought I said something to that effect when I first brought that up? Oh wait, I did! Here's the rest of that quote:
But it’s not a physical thing that you can poke holes in or tear apart; it’s a mathematical structure that’s well-defined, and the conditions where that structure breaks down — Planck scales — are also well-defined. The LHC doesn’t reach those scales, so we’re positive that we’re fine. Your analogy isn’t applicable here.
QED, I think.
From Michael Mooney on the (perceived?) invalidity of Special Relativity: "I’m still waiting for Ethan to disambiguate the difference between apparent length contraction (re: differences in what observers see) and actual physical shrinkage of physical objects as promoted by SR."
You wrote three things that you addressed here as a "response to my challenge." Only one was physics:
Regarding length contraction, It would take a clear disambiguation of the difference between *apparent* contraction (as seen/measured by various observers) and *actual physical shrinkage* as claimed in the pole- in- a- barn and the train- in- a- tunnel SR thought experiments… also applied to flattened planets (as seen by…) and contracted distances between stars, as per fast travelers with slow clocks.
If we had a way to travel close to the speed of light and take 3D measurements, we would be able to do exactly that. We'd be able to combine the effects of length contraction along with frame-of-reference motions of light-emitting objects (i.e., arrival times) to measure if length contraction is real. We can do this for individual particles (or bunches of particles) and confirm that special relativity's predictions are right. We've done it for fields (they exhibit length contraction at high speeds, like the electric field of an electron). But we haven't been able to do this for large, composite, macroscopic objects because of practical constraints. But there's no reason to believe that the physics is any different.
Your other two things that you wrote, however, complained about ontology. As a physicist, I'm not really interested in your (or my, or anyone's) inability to wrap your head around a physical interpretation/visualization/ontology of what these well-defined entities actually are. You are of the mindset that such a definition is nonsense and incomplete and insufficient. You are entitled to your own opinion, but, like I said, I don't find it interesting enough to even have a conversation about; it's not physics, nor is it physically interesting. You are going to disagree and ask me to respond, and I will tell you that I won't. Why not? Because I don't waste my time explaining myself to someone who's committed to misunderstanding me. And in this, you are.
From Frank on terraforming Mars: "Only possibility I see is if we can modify orbits of large asteroids and comets someday to collide with Mars to add both mass and water, and also make its orbit come closer to Sun."
Wait, and you thought bringing material to Mars the old-fashioned way was difficult? How much mass do you plan on adding? Because the entire asteroid belt is 0.5% the mass of Mars. You want to bring Mars closer to the Sun? How are you going to dissipate all that orbital energy? I think the bigger lesson is that if you add just atmosphere and then water, you get a world that works, as is, for hundreds of millions of years. That's pretty good!
Mars, the red planet, has no magnetic field to protect it from the solar wind, meaning that it loses its atmosphere in a way that Earth doesn't. But the timescale over which Mars will lose an Earth-like atmosphere needs to be calculated. Image credit: NASA / GSFC.
From Steve Blackband on the same topic: "So a magnetic field not needed to maintain the atmosphere. Cool.
However there is still the issue of radiation exposure without one, unless you live underground or under a dome."
Radiation exposure is an interesting question. While I may do lousy on Mars, someone who grew up in a radiation-rich environment would likely be fine. Somehow, if you grow up in a radiation-rich natural environment, you don't suffer the same ill-effects that someone who grew up in a more typical Earth environment would when exposed to such radiation.
The most radioactive inhabited location on Earth is the city of Ramsar in Iran, and here's the deal (from Wikipedia) on that:
Ramsar's Talesh Mahalleh district is the most radioactive inhabited area known on Earth, due to nearby hot springs and building materials originating from them. A combined population of 2,000 residents from this district and other high radiation neighbourhoods receive an average radiation dose of 10 mGy per year, ten times more than the ICRP recommended limit for exposure to the public from artificial sources. Record levels were found in a house where the effective radiation dose due to external radiation was 131 mSv/a, and the committed dose from radon was 72 mSv/a. This unique case is over 80 times higher than the world average background radiation.
People don't die or get cancer as expected. You might have "zero-generation" problems with radioactivity on Mars, but I have a feeling that the surviving colonists are going to wind up just fine.
32 images of the 2016 eclipse were combined in order to produce this composite, showcasing not only the corona and the plasma loops above the photosphere with stars in the background, but also with the Moon's surface illuminated by Earthshine. Image credit: Don Sabers, Ron Royer, Miloslav Druckmuller.
From Ragtag Media on a great list of eclipse apps: "It’s all about the apps:
This is beautiful, and worth sharing. Also, if you haven't caught it, did you know I just did a new podcast on the upcoming eclipse?
If these three different regions of space never had time to thermalize, share information or transmit signals to one another, then why are they all the same temperature? Image credit: E. Siegel / Beyond The Galaxy.
From eric on the horizon problem: "Can’t the horizon problem be solved by the notion of these causally separated locations obeying the same laws of physics?"
As Michael Kelsey said, the problem isn't that the laws of physics are the same; the problem is that different regions of the Universe are the exact same temperature despite being millions of light years apart! But if that's too hard, think about it in this other fashion: the Big Bang must have occurred at the exact same moment with the exact same initial conditions everywhere. How exact is exact? For the temperature fluctuations we see, the "bang" must have occurred in all locations with the same energy separated by timescales of no less than about 10^-33 seconds.
Over millions of light years, how can you make anything line up to that incredible degree of precision? I don't think you can, not without invoking some "the initial conditions were just finely-tuned like that." And maybe they were... but that's the essence of the horizon problem.
Binary stars with planets around them are common, but if the world containing Westeros orbited a binary planet, particularly if those planets were much more massive than it itself, physics can give us the orbits we need. Image credit: Stuart Littlefair / University of Sheffield.
From Sinisa Lazarek on the science of the Game of Thrones homeworld: "Would there be dragons?"
Physics will only get you so far, Sinisa. I can get you a world with chaotic rotations and seasons... but as far as exobiology, I don't think our science is there yet. Someday, perhaps.
Also, I noticed the arrival of jimbob on this post. This is a science blog, not a bible study group. He is now banned.
The Voyager 2 spacecraft took this color photo of Neptune's moon Triton on Aug. 24 1989, at a range of 330,000 miles. The image was made from pictures taken through the green, violet and ultraviolet filters. Image credit: NASA / JPL.
From Pawel on the possibility of life on Triton: "I cannot find any information on “black smokers” volcanoes on Triton. Sure, there is volcanic activity there, but what makes them similar to black smokers?"
Well, if you google "black smokers triton" you'll find that there's the Triton grill which can be used for smoking food, and that won't help you much. But Voyager 2 was remarkable in the science it collected. Yes, it found a mostly nitrogen atmosphere with some methane, where the methane was indirect evidence of volcanic activity. It has evidence of resurfacing, so that's more evidence of geological activity. And the presence of methane is different in different parts of the world, indicating a seasonal component -- seasonal heating from the Sun -- as well.
But we are absolutely certain that Triton is volcanically active. Along with Earth, Io, and Venus, only Triton also exhibits surefire volcanic activity. (This is likely due to tidal forces from Neptune.) But there's also this:
Those dark spots and streaks? Volcanic activity. As the New York Times reported back in 1989:
One of the pictures showed a five-mile-high, geyser-like plume of dark material erupting from the icy surface of Triton, the blue and pink moon that all but stole the show from its planet when the Voyager spacecraft had its rendezvous with Neptune last August.
The discovery, scientists said, confirmed the hypothesis advanced immediately after the Voyager encounter that explosive volcanoes probably fueled by liquid nitrogen accounted for much of the rugged terrain on Triton. This meant that Triton is only the third object in the solar system, after Earth and Jupiter's moon Io, known to have active volcanoes.
You can find more about it in the 1999 book, Satellites of the Outer Planets, by David A. Rothery.
The fabric of the Universe, spacetime, is a tricky concept to understand. But, thanks to Einstein's general relativity, we're up to the challenge. Image credit: Pixabay user JohnsonMartin.
From CFT on mathematical constructs: "Nothing actually moves in a mathematical construct like space time, It can’t even accommodate an impulse to motion, so the entire idea of it somehow affecting physical reality is quite pointless Platonistic hand waving."
You know that there are many mathematical spacetime constructs; Einstein's General Relativity was hardly the only one. The reason Einstein's formalism is remarkable, though, is because it accurately describes our observed, physical reality. That's all you need for physics. Mathematics is like taking the square root of 4. You get multiple answers: it could be +2 or it could be -2. Mathematics gives you all the possibilities a setup can admit. Physics? It has one answer, and that answer gives us our physical reality. If you can't wrap your head around it, you can either listen to the (dissatisfactory) analogies that people who are educated in it make, or you can go and become educated about it yourself. Enjoy the Christoffel symbols!
Look, it's everyone's favorite lunar Rover! The angles of the shadows on the Moon and the illuminated portion of the Earth in the sky clearly don't line up. Also, the dog is photoshopped. Image credit: NASA / manipulator unknown.
From Steve on fake astro pictures: "Its such a sad sad sad reflection of the ignorance in this nation regarding science and education that you felt it necessary to tell the audience that the dog digging on the moon (without a dogsuit) is photoshopped in.
And that I felt it necessary to add ‘without a dogsuit’…"
You are aware that there are many people who don't even believe humans landed on the Moon. They also think it was a hoax perpetrated by the American government, and that there was some sort of secret "staged area" where the Moon landings took place. So when you show them a picture like this, it jibes with their worldview. It confirms their belief, and so they're likely to dig in deeper. This may happen frequently in your own life, depending on who you encounter and what issues you speak about.
For me, I prefer to just watch the Rammstein video that gave the best "how to fake a Moon-like video" I think I've ever seen.
From dean on the climate science issue: "All true, but as denialists know, all they have to do is repeat their lies and let them sit. It’s quick and doesn’t require any science but they do seem like common sense statements to most people.. They know refuting them takes time and longer explanations that will lose the attention of people. Not promising."
You know, I am not a climate scientist. And I'm not really qualified to do climate science research. Which is why I ran my article past three separate Ph.D. climate scientists (technically, two climate scientists and one climatologist), all of whom vetted it and approved of all of my points.
But they made a separate point, one that I thought was quite important: their goal is to mislead. Their goal is to manufacture debate and uncertainty. Their goal is not to get the science right, nor to consider the full suite of evidence. Their goal is to keep the status quo in place. And perhaps if I keep taking the, "we have to all agree on the facts before we can discuss policy," then all they have to do is keep muddying the facts and they win. So maybe I need to take a different line of argument if I want to make a difference.
I'm thinking on this.
The size, wavelength and temperature/energy scales that correspond to various parts of the electromagnetic spectrum. Image credit: NASA and Wikimedia Commons user Inductiveload.
From Pentcho Valev on Einstein: "Spacetime is a consequence of Einstein’s constant-speed-of-light postulate, and this postulate is OBVIOUSLY false."
I'll tell you what: show me one measurement from any reference frame that indicates that the speed of light in a vacuum is not exactly 299,792,458 meters per second (I even gave you the value!), and we can talk about your ideas. Also, you're going to love yesterday's Ask Ethan when you get to it... but you have to read it. Writing your own "wall of text" (as other commenters have rightly called it) is equivalent to promoting your own pet theories and nonsense here. If that's all you have to write about, get your own blog, because if you don't knock it off, you won't be welcome here any longer.
Last chance to behave!
While most of the sky will darken in a total eclipse, there are portions during a total eclipse that will remain bright, as the Moon's shadow is smaller than your view of the entire 360-degree horizon. Image credit: Luc Janet.
And finally, to end this on a high note, here's Alan G. on... I don't really know, but it doesn't really matter: "Can’t wait to pop the corn and pop the top for reading these Sunday night. This is gonna be epic, and the start is not disappointing…"
There's always a lot to say, think, and reason out, and if you're curious about the Universe, I hope this blog (and even the forum) gives you something interesting to ponder. There's some amazing stuff going on in the Universe all the time, and I hope to see you continue on this journey with me. Have a great rest-of-your-weekend, everyone!
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From Pentcho Valev on Einstein: “Spacetime is a consequence of Einstein’s constant-speed-of-light postulate, and this postulate is OBVIOUSLY false.”
Ethan Siegel: "I’ll tell you what: show me one measurement from any reference frame that indicates that the speed of light in a vacuum is not exactly 299,792,458 meters per second (I even gave you the value!), and we can talk about your ideas. Also, you’re going to love yesterday’s Ask Ethan when you get to it… but you have to read it. Writing your own “wall of text” (as other commenters have rightly called it) is equivalent to promoting your own pet theories and nonsense here."
Measurements of the Doppler frequency shift; the Michelson-Morley experiment; the Pound-Rebka experiment. All of them unequivocally show that the speed of light is variable, not constant. I have already discussed these experiments many times here - you did not react.
Also, in my "wall of text" you can find many confirmations of subluminal motion of light in a vacuum and also superluminal motion. Just three examples:
Quote: “Physicists manage to slow down light inside vacuum […] …even now the light is no longer in the mask, it’s just the propagating in free space – the speed is still slow. […] “This finding shows unambiguously that the propagation of light can be slowed below the commonly accepted figure of 299,792,458 metres per second, even when travelling in air or vacuum,” co-author Romero explains in the University of Glasgow press release.”
Quote: “The speed of light is a limit, not a constant – that’s what researchers in Glasgow, Scotland, say. A group of them just proved that light can be slowed down, permanently.”
Quote: “For generations, physicists believed there is nothing faster than light moving through a vacuum — a speed of 186,000 miles per second. But in an experiment in Princeton, N.J., physicists sent a pulse of laser light through cesium vapor so quickly that it left the chamber before it had even finished entering. The pulse traveled 310 times the distance it would have covered if the chamber had contained a vacuum. Researchers say it is the most convincing demonstration yet that the speed of light — supposedly an ironclad rule of nature — can be pushed beyond known boundaries, at least under certain laboratory circumstances. […] The results of the work by Wang, Alexander Kuzmich and Arthur Dogariu were published in Thursday’s issue of the journal Nature.”
But you cannot think of experiments that disprove the constancy of the speed of light, can you, Ethan?
George Orwell: "Crimestop means the faculty of stopping short, as though by instinct, at the threshold of any dangerous thought. It includes the power of not grasping analogies, of failing to perceive logical errors, of misunderstanding the simplest arguments if they are inimical to Ingsoc, and of being bored or repelled by any train of thought which is capable of leading in a heretical direction. Crimestop, in short, means protective stupidity."
Late comment on the tethered object (probe) dropped down to a black hole's event horizon: If you consider time dilation, the folk in the spaceship will never live long enough to see the probe actually cross the EH. While the probe, crosses the EH in finite time in its own frame, it is seen by the spaceship inhabitants as approaching the EH ever more slowly, with its image turning deep red. It approaches the EH asymptotically but does not cross it in the spaceship inhabitant's lifetime.
They never get the opportunity to even try to pull the probe back out.
Oh sure I am still intrigued by 'creating a catastrophe at the LHC'.
Yes, it seems you misunderstood.
The glass breaking that I referred to previously wasn't a metaphor for SpaceTime. The glass represented the Protons that surround the collision spot, you know the Atoms that make up the metal of the beam-pipe-funnel; the speaker creating the high pitch tone that made glass break stood for the Protons that are colliding; and the air between speaker and glass represented SpaceTime. Yes I know SpaceTime isn't a substance, but let's say it can transmit Gravity waves created during the particle collisions
Thus the speaker (p+p+ collisions) isn't breaking the air (SpaceTime), it's just shaking up the air at an intense high rate and the glass (Protons surrounding the collision spot) feels these vibrations (GWs) and snaps after a while, releasing the build up tension.
The point about 'noise' at the LHC was about being able to detect soft Gravity Waves produced during High-energy
particle collisions. Of course the LHC is excellent at detecting and defining what comes out of these collisions, no question about that, but to detect soft GWs there is (probably) too much 'noise'. Imagine placing the LHC next to LIGO, would LIGO still be able to detect and filter out GWs, probably not because the LHC produces too much 'noise'.
Now the safety argument for the LHC is that there's no possible catastrophe because we have Ultra-High energy Cosmic Ray collisions that are 50 times more powerful than those of the LHC. That's a fair argument, but the problem I see is that these collisions happen at a very low frequency, a loud bam and that's it. You could compare this to having the fragile glass and a loud clap of hands, it won't make the glass break, mh, perhaps a very loud explosion could break it, but then has to be 150 times louder just to put a number on it.
Anyway if we look at the LHC than we have a frequency that is a billion times higher than Cosmic Rays in nature, so what we could have is a high pitch tone of soft GWs shaking up the Protons of the metal that surrounds the collisions spot, straining them out … until the point that those Protons snap, this caused those metal Atoms to split and releasing their energy and possibly setting off a chain-reaction.
Similar to lighting a fire with a loupe, you concentrate 'normal' light in one spot at a piece of paper, at the focus point the paper starts to heat up and combust at some point. It's the high frequency and density that makes all the difference.
Since when is 'cesium vapor' a vacuum?
Did I say it is a vacuum? The publication in Nature is about superluminal speed - vacuum is irrelevant in this case.
"show me one measurement from any reference frame that indicates that the speed of light in a vacuum is not exactly 299,792,458 meters per second"
According to who? Are your climate scientists also sociologists? Have they polled those who oppose them? I’m guessing the answer is ‘no’ on both counts. Speaking as one who Dean’s comment was specifically directed against, I absolutely do look at the full suite of evidence and my goal is not to mislead. That is why I am able to post published work from respected experts in the field that support the various points I make.
I am very confident in making the statement that even though I don’t now know who the 2 climate scientists nor the climatologist who blessed your work are, they are all shit scientists. For intellectuals not expert in the fields of psychology, or group dynamics, who have never met me or likely never even read a single word I’ve written, to surmise that I am part of some monolithic movement they’ve imagined with my goal being to mislead is something that is contrary to what science is.
If they want to have opinions, that is fine. Everyone does. Where it becomes a problem is when they start mixing their unsupported opinions in with their scientific work product as just happened here. That they are engaging in vilification of an ‘other’ group makes zero surprise. It is tribalism.
Secondly, they absolutely should have warned you about Santer et al (2017) published in Nature. A third of Heartland’s points had to so with the disparity between models and observations. There is no excuse for a climate scientist to not know about that study. No Excuse. You may not have known about is as it is fairly recent and many of the sites you read I suspect are whistling past the graveyard on it, but there’s no excuse for climate scientists. What you wrote on that topic is wrong, demonstrably, because published science from people far more respected in the field than the ones you asked said so.
If you feel the need to shout me down so that you can use your platform to present the approved “full suite of evidence” and leave out “misleading, not to be included in the full suite because they muddy the facts” science such as Santer(2017), NOAA data that shows falling relative humidity, etc., just let me know.
"So maybe I need to take a different line of argument if I want to make a difference."
In what way(s) do you thing you can make a difference other than by providing the best Science Explanations you can?
"In what way(s) do you thing you can make a difference other than by providing the best Science Explanations you can?"
Ethan could start by looking at the original unadulterated data sets.
The reason certain "Ph.D. climate scientists (technically, two climate scientists and one climatologist)," approve is because they are using same data sets that have been tampered with:
In fairness, @Ethan has looked at the unaltered data sets. He's chosen not to use them and has given scientifically based reasons for doing so. You may quibble as to his reason being valid but you can't say they aren't in the "full suite of evidence" he's looked at. They absolutely are.
If you want to know where @Ethan is falling very short, it is the economic end of the "full suite of evidence". For instance, S. Hsiang el al.(2017) recently published in Science shows roughly 1.2% (+/- 0.85%) of GDP retardation per +1°C on average globally. The American economy would be less impacted (error bars include possibly no financial impact at all to America) and the developing world more impacted. It has been written up in the Economist and other fairly large outlets.
I would bet money @Ethan doesn't know about that paper, or the big one before that, or the big one before that. He may have read some screechy blog post about how much something cost and global warming's destruction of it would cost 'x', but when economics is mentioned it is almost impossible to drag @Ethan to it even though it is a huge component in making a decision to do something or not.
@Ethan is even more adverse to looking at the economic impacts of proposed solutions. He's so adverse that he typically won't even nail himself down on what should be done. Usually it is "something should be done", or we "must demand action", or other generically vague platitude.
At least @Ethan is honest about not being a Climate Scientist. He's even written in the past about his engagement in advocacy. The line about his questioning his own methods so as to be a more effective difference maker is only confirmation on what he's written before. @Ethan is not impartially evaluating the "full suite of evidence" even if he is a little better in the subsection of popular scientific evidence that supports warming. Given his glaring weakness in certain areas of evidence concerning what he is advocating for, I found it galling that he chose to include the apparently Ph D. approved character jab directed at those in opposition. What are we in Middle School?
How many masses can you put into the same space time matrix? And have them, you know, interact? Just asking, because as usual, you side step the issue, and quack a lot about your education, what you think other people don't konw, the people you do know, blah blah blah.. Explain how useful a model of gravitation is that can only contain ONE mass? It's useless. How exactly are you introducing more than one mass into a non linear solution 'Oh knowledgeable One', because last I checked, there is no mathematical solution to a two body problem in GR. Please do YOUR OWN homework and look up what Pseudo-Riemannian means mathematically. It's non linear you little math genius, which means it has the same limitations of all other non-linear equations. Newtonian equations are linear, you can add additional masses provided you can do the complex calculations, In GR you can't do that.
"... because last I checked, there is no mathematical solution to a two body problem in GR."
maybe check again .. i.e:
Numerical relativity has been flourishing in the last 15-20 years
So what? I've previously stated that your analogy is not valuable, but even if we assume it's relevant, it provides no reason at all to think these collision pose any sort of danger. Let's think through what your analogy could mean:
1. Analogous to the atoms in the glass having the bonds between them broken, you could conclude that the bonds between the protons in the LHC target will be broken. That will indeed happen. There is no cataclysmic danger in this.
2. Analogous to the bonds between atoms in the glass being broken, the target protons themselves could be broken up into constituent quarks. That also indeed happens. There is no cataclysmic danger here.
You are trying to claim something more analogous to: when the singer's voice breaks a glass, this will lead to a catastrophic chain reaction in which all the bonds holding atoms in glass all other the world will break. But that is clearly not what happens. It's a local effect. your analogy is about a local effect limited to the particles impacted by generated signal, and affecting no other particles. So your analogy - even if it were valid - in no way supports your claim of any sort of chain reaction danger.
"From Michael Mooney on the (perceived?) invalidity of Special Relativity: “I’m still waiting for Ethan to disambiguate the difference between apparent length contraction (re: differences in what observers see) and actual physical shrinkage of physical objects as promoted by SR.”
I"m still waiting. You stick to length contraction on micro scales. I've never questioned that enough force applied to micro particles to boost them to near lightspeed can compact them as per length contraction. But there is no evidence that this applies to macro objects.
". But we haven’t been able to do this for large, composite, macroscopic objects because of practical constraints. But there’s no reason to believe that the physics is any different."
Yes, there is. Extreme force applied to micro particles can compact them. But THERE IS NO PHYSICS that explains a very fast train 100 meters long shrinking to fit into a 50 meter tunnel... or a long pole into a short barn. Much less a FLATTENED EARTH. No disambiguation of the difference between apparent and physical shrinkage! ("Ask Ethan," but don't expect an answer.)
"You wrote three things that you addressed here as a “response to my challenge.” Only one was physics:"
(The length contraction issue... still not addressed for macro objects or inter-stellar distances... "contracted distances between stars, as per fast travelers with slow clocks."
"Your other two things that you wrote, however, complained about ontology. As a physicist, I’m not really interested..."
First, It matters whether or not time is an entity which dilates.
You are clearly not interested in the physics of what different forces were applied to different clocks to accelerate them to different velocities... and make them tick at different rates. But it IS a physics issue! It requires ignoring that to insist that time is an entity measured differently at different velocities (or gravity fields.)
Finally regarding the "fabric of spacetime," you said it is "nothingness itself" and then you go back to the standard version of it as a malleable medium (as per Wheeler.) So you still refuse to disambiguate that as well as all above... and you call it an answer and claim that I am "committed to misunderstanding" you.
I am committed to truth and honesty in science. Try it sometime.
Thank you for your patience Ethan! My own physics education was undergrad only and multiple decades ago at that. Questions above our level were usually rebuffed, so thanks again!
Your assessment is correct. At this point my 'claim' is pretty weak, there is no guarantee for a chain-reaction.
But for this reply I am going to let it rest and bring up a slightly similar dispute in history with the construction of the first Atom bombs and the fear of setting the sky on fire:
"In 1942 the decision was made to research a fission bomb. However, Edward Teller continued attempts to gain support for creating a much more powerful thermonuclear bomb (fusion bomb). It was during those early years, when fusion was not well understood, before even the first controlled fission reaction, that Teller first speculated about how a fission bomb might ignite the atmosphere with a self-sustaining fusion reaction of Nitrogen nuclei.
Anyway back to 1942. Upon hearing the prospect of an uncontrolled atmospheric reaction, Oppenheimer set Hans Bethe to look into the matter. Bethe, using early IBM digital computers to achieve his results, calculated that a fission reaction could not induce a thermonuclear reaction in the open atmosphere. Research resumed and the first A-Bomb was constructed." - https://www.metabunk.org/debunked-scientists-risked-destroying-the-eart…
Now the point that I want to make is that those guys investigated the possibility, and did the calculations.
But for the LHC a chain-reaction due to the high density and frequency of collisions is not even discussed and is hand-waved away. While imho it should also be taken seriously.
SR does not claim the force compacts objects (or space) in the direction of travel. This has been explained to you many times.
I'm interested! So give me your equations of how force applied to a clock makes it tick at a different rate. Show me your physics. That would be progress, because we could test your equations experimentally and see if they hold up.
If you are dedicated to truth and honesty in science, you should start representing what SR claims truthfully and stop misrepresenting it as claiming some compaction of the object or shrinkage of space happens to the universe when something moves relativistically.
Why, if you're so interested in truth, do you constantly claim it says something we've explained to you repeatedly that it doesn't say?
They have investigated the possibility. They have taken it seriously. They did the calculations. They published the results almost 10 years ago.
Want to read it? Here is the technical report. Here is a follow-on study, with links to several other additional supplemental and supporting reports all on the same subject(s).
So, now that you've claimed that all you wanted was a substantive discussion of the possibility - for science to 'take it seriously' - and I've shown you that that substantive discussion was had and that mainstream science did take it seriously, did do the calculations, will you stop and be satisfied?
Somehow I doubt it. I suspect that like many cranks, the only thing that counts for you as "investigating the possibility" or "taking it seriously" would be "agreement with Elle." Like the No True Scotsman fallacy, you protect your belief with a No True Investigation fallacy; if the mainstream community disagrees with you, that conclusion taken as evidence by you that they didn't investigate the issue sufficiently. You do not accept the possibility that science has taken your idea seriously and rejected it as erroneous.
Australia Weather Bureau Caught Tampering With Climate Numbers:
"They have investigated the possibility."
I am sorry, but their study doesn't address the frequency and density issue between the LHC and Cosmic Rays in nature (see graph/link), they only looked at the process as individual events. Something like 'critical mass' in nuclear physics isn't even considered. Keep in mind that every 'massive' particle is a hole in SpaceTime.
eric #16: ""SR does not claim the force compacts objects (or space) in the direction of travel. This has been explained to you many times."
We have been over your misunderstanding of SR's claims before as I have cited the often used SR pseudo-examples/ thought experimenst of the long train fitting into a short tunnel and the long pole fitting into a short barn... choose your own units of length.
There is also the standard SR claim of shortened distance between stars as hypothetical travelers' clocks tick slower as they approach lightspeed. There is also the claim that a flattened Earth (as such high speed travelers approach) is "equally valid" as a measurement of its diameter length. (It obviously can not be both spherical and pancaked. It's one or the other. Take an educated guess which is "valid.")
Ethan has said that all such contractions are not just apparent but real physical contraction ("Absolutely.") Of course *apparent contraction* would require no compacting force as would physical contraction/compaction in the case of all physical objects. I plead for Ethan's official disambiguation of the difference... to no avail.
"I’m interested! So give me your equations of how force applied to a clock makes it tick at a different rate."
The concept of what one is describing must precede the math quantification. Empirically, we observe clocks traveling at different speeds keeping time differently. What is different about each clock? Each was exposed to the force of acceleration to reach a different speed as compared to others. Same with clocks in different gravity fields. More *force* of gravity makes them tick more slowly.
Clocks don't "measure" different rates of time passage, as if time were a variable entity. They just tick at different rates according to the forces they experience. **
Thermometers measure temperature and we understand the physics of it. What is the physics of clocks measuring time? (See ** above.)
"Keep in mind that every ‘massive’ particle is a hole in SpaceTime."
Where did you get that? And what's up with quote marks for "massive" ?
Mind sharing where you got that notion of holes in Spacetime? Or is that just another chelle theory claiming to be scientific fact?
Uh, mass curves space, thus creating a hole in SpaceTime, just like we can have a Black hole, but the latter have a gravitational field so intense that no matter or radiation can escape. Nonetheless both are holes.
Regarding the quote marks, photons also bend SpaceTime, just a little, but they are presumably 'massless', at least they have no rest mass.
So nothing of my own making here. ?
"Uh, mass curves space, thus creating a hole in SpaceTime..."
wow... just wow.. so after years of being here and all the articles about forces, particles, gravity, spacetime etc... that's the picture you have? Wow! You think that spacetime is like a swiss cheese full of holes that matter makes. Unbelievable chelle.. just unbelievable. And what exactly is in those holes of yours.. since you say there's no spacetime there?
Actually it was me who was flabbergasted at first when you asked that question.
Anyway, now you come up with an other strange question:
"And what exactly is in those holes of yours.. since you say there’s no spacetime there?"
Nowhere have I written that there's no SpaceTime in those holes. A hole in this case is a depression in SpaceTime.
Elle H.C. wrote:
So what you're saying is the existence of 'massive' particles depress, or perhaps could be better phrased as 'warp the fabric of space in its vicinity'. I would guess the depressions are like the wells settlers dig in areas so they can get water only instead of water there is gravity in the well. You're saying both infinitesimally small massive particles and black holes have these gravity depressions in space-time? I don't know. That sounds like crazy talk.
You are presenting here your own strange analogy with settlers and all; and then you follow it up by saying "that sounds like crazy talk".
Mh, what do you want me to say to that?
yes, mass/energy affects the geometry of space time. more precisely, it acts on the geodesics, meaning straight lines. but there are no holes in spacetime. particles or planets don't make holes in spacetime like you wrote.
any energy/mass acts on spacetime in principal. the math doesn't really care if it's a star or a particle. but in case of particles, the effect is so incredibly small that it's just overshadowed by other forces. think of even a small magnet being stronger than the effect of the whole earth curving spacetime. to summ...chelle's claim that particles create holes in spacetime is just nonsense and wrong
"particles or planets don’t make holes in spacetime like you wrote."
How did I wrote it?
Fact is that I only mention 'holes' without any further descriptions, except that the curve SpaceTime.
BTW Here's an example of how the curving 'works':
Perhaps you prefer to talk about 'valleys' instead of 'holes', in that case our differences are only a matter of semantics.
Yes, they did. They pointed out that cosmic rays of higher energy don't provide any evidence of the reactions you insist are there, and if you know anything about Einstein's photoelectric effect, you should know that increasing luminosity (flux) generally can't result in a reaction if all of those added particles are below the energy threshold needed to cause the reaction to occur.
If they didn't consider it, it's because the analogy undermines your claim and makes their stronger LOL. In neutron induced fission there is no new physics that occurs only when you get a sufficiently high flux of neutrons together. Instead, just as these physicists say about cosmic particles, and completely opposite to what you want to claim, we can observe individual neutron induced fission events producing exactly the effects seen in a criticality event but on a smaller scale. One neutron hits one nucleus, it produces 2-4 neutrons out. Many neutrons hit many nuclei, they each produce 2-4 neutrons out. The small scale/single events are exactly predictive of the large scale/high flux events.
So Elle, if you really think your reaction is metaphorically like a fission criticality, then your theory must predict individual high energy cosmic rays would produce your claimed effect on a small scale.
But I'm going to say "here we go again," because I'll bet you're going to use another crank move here - faced with the fact that your argument doesn't support your conclusion, you'll simply abandon your like-fission argument in order to keep your belief in your conclusion intact. No investigation will ever be good enough for you. No amount of us pointing out that your own arguments imply cosmic rays should produce evidence of your claim will change your mind. Your conclusion is immune to evidence and argument.
The effect of the longer train fitting into a short tunnel is explained in SR by the non-simultenaity of different frames of reference, not through a physical shrinkage. One would think that your "decades of studying it" would have given you an understanding of that. DO you understand that?
Sure it can, the same way a charged particle can have a magnetic field and not have a magnetic field at the same time...depending on the frame of reference of the observer. An observer riding along on that particle (Alice) will feel and observe its electromagtenic properties as only a charge, with no magnetic field. Someone moving with respect to the particle (Bob) will feel and observe that it has a magnetic field. Alice and Bob will also disagree on the charge of the object. But they will agree on the combined electromagnetic properties of the particle, because that is the conserved quantity; E and B are not separately conserved, their combination is. Likewise, length and time are not separately conserved, their combination - as represented by the spacetime interval - is.
And before you accept the former while rejecting the latter, note that both claims come from exactly the same relativistic physics. There is no internally consistent way to accept one without the other. You get both under SR, and you get neither under NM.
I get the concept. Everyone gets your concept. You have described your concept in hundreds of posts over months ad nauseum. But you don't have any math to back it up, do you? No quantification of your concepts.
Is that a correct and accurate description of the current status and sophistication of your idea? You have a qualitative description but no quantified one. No math to go along with your idea? A yes or no answer is sufficient, if you please.
that example is a simplified analogy/visualization. for one, spacetime is a 4d construct, not a 2d sheet with 3d objects making dents in it. so no, no valleys or holes or depressions or any other thing you want to throw. particles are not holes in spacetime. accept your mistake, learn from it and move on. don't dig an even deeper hole for yourself.
@Sinisa Lazarek #26
Sarcasm doesn't work well on the internet. I do know that and yet I can't help myself. In all seriousness I do get the classical idea of gravity and think Chelle is wrapped up in semantics with poor choice of words. I was having fun with Chelle's "hole" and "depression" by juxtaposing them with the more traditional terms of gravity wells and gravity itself being a warping of space.
@Elle H.C. wrote:
Not a thing. You're good. I'm good. I was just trying in my own prickish way to unite parties who seemed to be talking past each other. I could see that you were using non-traditional verbage to describe a traditional gravity analog. When you put a bowlilng ball on a taut sheet it makes a depression like in the YouTube video you linked to.
"that example is a simplified analogy/visualization."
The same goes for calling a particle a 'hole', 'depression' or 'valley'. A particle fracking curves SpaceTime, now how does a that situation look loke, you name it, go ahead I am waiting.
"Yes, they did. They pointed out that cosmic rays of higher energy don’t provide any evidence of the reactions you insist are there"
Oh Christ, no they did not, Either you don't understand the mechanism I propose or you haven't read their safety paper.
"… if you know anything about Einstein’s photoelectric effect, you should know that increasing luminosity (flux) generally can’t result in a reaction if all of those added particles are below the energy threshold needed to cause the reaction to occur."
Again you're not getting it, or play the fool on purpose. I gave the example in the last paragraph at my first comment here (see #3), with the highly concentrated flux of Photons and the paper that starts to burn, but that's perhaps no 'general' case?!
"if you really think your reaction is metaphorically like a fission criticality, then your theory must predict individual high energy cosmic rays would produce your claimed effect on a small scale."
'A critical mass is the smallest amount of fissilematerial needed for a sustained nuclear chain reaction.'
Have you any idea how they have to build an A-bomb to reach critical mass, adding lots of pressure to the explosion going? That's not something that just happens in nature, it is a process of artificially increasing density and frequency.
Now my point is exactly that the frequency and density in nature is too low and at a safe level, but at the LHC it is a billion times higher, is that still safe? Have you even looked at the graph?
"The same goes for calling a particle a ‘hole’,"
no one ever (except you) called stars "holes in spacetime".. let alone particles. Just like no one says fish are holes in the water. Or, i don't know, chairs holes in air. For obvious reasons. A hole in paper means there is no paper in the hole.. that's what makes it a hole.. or a hole in the wall. Thus saying anything is a hole in spacetime implies that something just created a void in that spacetime. Which is wrong and why particles are not holes in spacetime.
The only valid use for "hole" that comes to mind (and why it was used), was i.e. of Dirac sea model. Where i.e. a positron was literally a hole in a sea of negative particles. And when you say "particles ARE holes in spacetime".. that image comes to mind, and that claim is wrong.
Since you like drawing, create a 3D solid grid (not a 2d sheet below the object), place a 3d sphere inside it, model geodesics as they should be... and if you end up with anything like a hole or a valley, I will withdraw my statements.
this is probably the closest to the real thing. No holes.
"Thus saying anything is a hole in spacetime implies that something just created a void in that spacetime."
Are you implying that 'Black holes' are a void in SpaceTime?
My reasoning is that if 'Black holes' are massive objects that create 'holes' in SpaceTime, that all lighter massive objects are also 'holes' but not black.
Thanks for the video, you could say that mass pinches SpaceTime, the relationship to 'hole' comes perhaps more from the fact that matter 'falls' towards it, e.g. fall into a hole, a depression or in valley.
Anyway as already pointed out calling a massive particle a hole is a matter of semantics, and you translating it into a void is not what I was referring to.
Besides that we are drifting away from the point I was trying to make, about how all massive objects take up their place, relating to creating ripples in SpaceTime and shaking 'hole-composed' structures apart, thus taking a different/deeper look than regarding everything as 'simple' point particles.
"hole" in black hole was there because of the "wormhole" from the original idea, not because they make holes in spacetime. But anyways... you've demonstrated time and again that you don't really care about reality or correctness, only your own agenda.
"“hole” in black hole was there because of the “wormhole” from the original idea"
I call BS.
The term Black Hole comes possibly from 'Black Hole of Calcutta':
Anyway a neutron Star collapses into a 'Black hole' so it's fair to say that before the collapse it was a 'Normal hole', and what is one large 'Normal hole' made off, many small 'Normal holes' I presume.
If you don't believe that's not 'correct' than don't, but in reality mass creates holes/depressions/valleys in SpaceTime.
Let's assume that all possible clocks will tick more slowly when in motion. That's not really a bad assumption since it appears to be completely borne out experimentally. This includes clocks based on any kind of physical oscillation, lifetimes of unstable particles, light travel distances, or any other clock you can imagine.
Now, we are left with what is essentially a philosophical, rather than a scientific issue. You are claiming that it is the forces acting on these clocks that cause them to tick more slowly. Relativity theory tells us that it is the variation of time with respect to reference frame that causes the effect. What's the difference? From a scientific point of view, if ALL possible clocks tick more slowly for some reason, that is exactly equivalent to the statement that the rate of passage of time is slowed. All possible experimental observations are the same regardless of which of these you want to put forth. There is no difference between "all clocks are affected in such a way under these specified conditions that they will indicate less time has passed" and "time is passing more slowly", at least from a scientific standpoint. Identical predictions of experimental result means that the theories are scientifically identical.
Consider it this way: let's assume that you're correct. Time really does pass at the same rate for all observers, but clocks are not capable of measuring this constant rate of time passage. How would you determine that this is correct? The only way we have to measure the rate at which time passes is via clocks. How else could you verify that you are correct when you state that the actual rate of time passage is constant?
While there is no scientific difference between the notion that time is constant and clocks are incapable of showing this and the equivalent notion that time is not constant, there is philosophical basis for preferring the latter, namely Occam's Razor. To hold the former, for each possible type of clock, you must come up with some physical mechanism by which the clock will fail to properly indicate the passage of time when it's motion is altered. There will be one mechanism for a pendulum clock. There will be a completely different mechanism for a clock based on light travel. There will be an entirely different mechanism explaining why lifetimes of unstable particles are affected by motion, etc. With the latter, there is one explanation for all of these phenomena, namely that time is not an invariant for all observers. That's the simpler, and hence the preferred, explanation.
"I call BS."
You can call BS all day if you want.
"This analysis forces one to consider situations... where there is a net flux of lines of force, through what topologists would call "a handle" of the multiply-connected space, and what physicists might perhaps be excused for more vividly terming a "wormhole".
— Charles Misner and John Wheeler in Annals of Physics (1957)
Sorry, but I am not seeing how this explains that 'Wormhole' was the 'original idea' and that (Black) hole was derived from it.
BTW the hole of the Wormhole is also not a void in SpaceTime, something that you tried to pin on me.
Note, there is even the term 'White hole':
"In general relativity, a white hole is a hypothetical region of spacetime which cannot be entered from the outside, although matter and light can escape from it. In this sense, it is the reverse of a black hole …"
So everything except Worm-, Black- or White hole is a Normal hole!
A black hole is no more a hole in spacetime than the big bang was a bang. Things in science get their names for all kinds of reasons. The names often do not reflect everyday use of language.
In actual fact, a black hole is a region of spacetime that is highly curved. This high degree of curvature causes unexpected and interesting effects. For example, it leads to the fact that not even light can travel from a point within the event horizon to a point outside the event horizon. It leads to the observation that an infalling object will appear to a distant observer to take an infinite time to reach the event horizon and that it will be spatially spread out across the entire E.H. It leads to the "inversion" of space and time in a sense, namely that the spatial direction "toward the singularity" becomes a timelike vector, rather than a spacelike one. IOW, an infalling particle can no more move away from the singularity than an everyday object can move backwards in time.
None of these effects though implies that there is a hole in spacetime. There is no point in a black hole where spacetime does not exist. It exists everywhere, just with properties that are much different than what we are accustomed to.
@Sean T #43,
"There is no point in a black hole where spacetime does not exist."
You don't say.
Clearly you haven't followed the debate, please read through it before lecturing me and insinuating that I believe that holes in SpaceTime are like holes in cheese as SL tried to pin on me. An apology would be welcome.
"The effect of the longer train fitting into a short tunnel is explained in SR by the non-simultenaity of different frames of reference, not through a physical shrinkage. One would think that your “decades of studying it” would have given you an understanding of that. DO you understand that?"
You still don't understand what SR claims. I have argued forever that length contraction is only an **apparent** shrinkage depending the observers or the objects speed and the different times it takes **images** to reach different observers. But SR claims that a 100 meter train will physical fit into a 50 meter tunnel. That can not happen without (bogus) physical shrinkage of the train. DO YOU UNDERSTAND THAT? Yet Ethan and mainstream SR insist that objects in the macro- world would in fact shrink if accelerated to near lightspeed like particles in an accelerator. No reason to believe they wouldn't, he insists. Check his week 170 comments to me... and then quit promoting your own version of SR.
It's ironic but I agree with you that observational differences can not make physical objects shrink. But that isn't what SR claims... that differences in lengths depend on observational differences. And yes, they claim it applies to distances between stars and diameters of planets too!
Get it yet?!
@Sean T #40
You ignore whatever doesn't fit with "time dilation" doctrine as an entity "woven together with space." You ignore my whole argument in #19. The last two paragraphs sum it up:
Clocks don’t “measure” different rates of time passage, as if time were a variable entity. They just tick at different rates according to the forces they experience. **
Thermometers measure temperature and we understand the physics of it. What is the physics of clocks measuring time? (See ** above.)
How about at least answering the last question with a physical explanation... not just a repetition of time dilation doctrine.
@Sean T #40
I missed an important piece. You said, " The only way we have to measure the rate at which time passes is via clocks. How else could you verify that you are correct when you state that the actual rate of time passage is constant?
Just like ignoring each clock's different history of exposure to different forces, you ignore the fact that clocks are instruments calibrated to units based on Earth's day and year (now very precisely.) As such a year is standardized as an Earth orbit and the day (and all its micro-divisions) is standardized as one revolution.
I'm sure other worlds must "keep time" in a similar fashion.
Nobody but fools are fooled by slow ticking clocks.
You must also have trouble with the bouncing ping pong ball inside a train that is in motion tracing 2 different paths in space simultaneously, depending entirely on the frame of reference of the observation.
I'm a Ph.D nuclear chemist with double digits (but not triple) publications under his belt. So, yeah. How about you? Why should *I* think *you* have any idea how to build a nuclear bomb?
It did happen in nature. So tell me, oh Guru Of Reactions Nuclear, how did you not know about Oklo?
But here's the really key point, which you seem bent on ignoring: we can react one neutron with one uranium atom and watch the exact same products come out as what comes out in a fission chain reaction. A criticality event produces no new particles that a single reaction doesn't.
So if you are going to claim this is analogous to your proposed world-ending reaction, then we should be able to watch the LHC fire one subatomic particle at one target nuclei and produce a small number of strangelets or whatever other crazy thing you think will be produced. You shouldn't need to invoke any new physics for large numbers of particles, because that's not how the example nuclear reaction YOU chose to use as YOUR example works in the real world.
Yes, it can...as long as observers in different frames of reference experience time and space differently. Which they do, in SR. The same way observers in different frames of reference experience the momenta of a moving particle differently. The same way they experience the magnetic and electric components of an electromagnetic field differently.
SR claims L = L0/gamma, where gamma is the Lorentz factor. It does not claim L changes with v. It does not claim L0 changes with v. If you think it claims L changes with v, show me the equation where it says that. There is none.
And what about your mathematical description of your idea? I.e. the idea that clocks slow down when they are accelerated. Do you have a mathematical description of that?
I doubt it. And it shouldn't take decades to produce. I can even whip you up the beginnings of one. d[something]/dt is proportional to dv/dt. Just provide the [something], the k needed to turn "is proportional to" in to "=", and any other constants you think are in that equation. C'mon MM, don't you want to propose a testable hypothesis of your idea?
"we can react oneneutron with one uranium atom and watch the exact same products come out as what comes out in a fission chain reaction."
"…we should be able to watch the LHC fire one subatomic particle at one target nuclei and produce a small number of strangelets or whatever other crazy thing you think will be produced."
The keyword here is 'fire'. What we do at the LHC is fire Protons into each other by accelerating them close to the speed of light which is needed to break them apart.
You can compare this to smashing (firing) two glasses into each at look at the bits and pieces flying around.
But thats not the process (firing) that I am talking about, what I'm looking at is generating 'sound waves' that make the glass break.
What you can do to break the glass, is *tick* the glass, record the sound and replay the sound at a high pitch and amplified, so the glass is softly pushed over and over again, absorbing all the energy until it snaps!
So if you play the sound only a fraction of a second the glass wont break and it can disperse the energy, only after a prolonged period will it snap, the same goes for the strength of the signal. Frequency and density.
Now let's look back at the collisions at the LHC, than we could compare that as the speaker sending out the recorded *ticks* at an extreme high frequency and density, sending out Gravity waves like the 'sound waves'. The question now is could these waves make the surrounding Protons snap?
Here we end up at your argument: "…we should be able to watch the LHC fire onesubatomic particle at one target nuclei and produce …"
The first question is, can a Proton 'snap' because of an intense GW signal?
To start analyzing this we need to detect and measure the strength of the GWs coming out of the collisions, and it is at this point that the discussion started a few posts ago with the liaison to LIGO and the detection of Gravity Waves, which I discussed here in my first comment at #3.
The other issue is the comparison with Cosmic Rays and noticing that they aren't 'snapping' surrounding Protons, but their frequency and density is much lower as shown in the graph.
One last point is let's say that we can make one surrounding Proton snap, when surpassing a certain frequency and density threshold, than we wouldn't be noticing it because we're not able to process the data in realtime, so we'll be continuing heating up billions of other surrounding Protons as well, not able to see the 'smoke signals'.
" ... collisions at the LHC, ....sending out Gravity waves"
you should inform yourself first what is needed to create grav. waves and how, before making the claims in #51. When you do, you'll realize (hopefully) the nonsense of it.
"you should inform yourself first"
Someone who works at the LHC told me that the produced GWs are something like 50 to 100 orders of magnitude too weak to be detected, and also 20 to 50 orders of magnitude too weak to play a role in the collision.
But that's for individual events, so you still need to take into account the high frequency and density of the experiment, you know lots of small ones adding up.
It's like starting a fire by rubbing sticks, only the friction buildup will turn the friction point from wood into hot ember.
@ Elle #53
I would be very much interested in learning how that works (maybe you could ask him/her again) and if they published anything on the subject. Because, from everything I looked at, and on arxiv, I couldn't find anything about particle collisions generating gravitational waves. Nor any actual numerical models that define how strong/weak they would be.
I will apologize if you can explain to me what you mean by "hole". A hole in the earth's crust is a place where no material of the crust exists. A hole in a piece of paper is a place where no paper exists. A hole in my shirt is a place where none of the material composing my shirt exists. What else could you possibly mean by "hole in spacetime" besides a location where spacetime does not exist?
I was using "clock" in a wider sense than the usual usage. A clock is simply anything that undergoes a periodic motion. The earth's rotation and the earth's revolution around the sun both qualify as clocks. They also are both affected by the motion of the observer, just like any other clock. A hypothetical observer on a fast spaceship flying through the solar system WOULD measure a different length of time for the frequency of the earths revolution or rotation, so these are NOT valid standards for time; they are affected just as any other clock is.
Not to mention, of course, that your proposed time standards are actually quite poor as standards. The length of the day and the length of the year varies quite a bit. That's the reason that the frequency of a transition of Cs atoms is used as the definition of our time standard, rather than either of those phenomena.
All of which still begs the question of how you know that the flow of time is constant. ALL clocks, including the ones you propose as being absolute standards are affected by the motion of the clock and the observer (at least in your view). Like I said above, to truly make your view scientifically acceptable, you'd have to come up with a mechanism to explain why each type of clock is affected by its motion. Why does a rapidly travelling observer measure a different length for the earth's year? Why is a clock based on a mechanical oscillator affected by motion. Why is a clock based on light speed affected. Why is a quartz crystal clock affected, etc.
I will ask.
@Sean T #55,
What I've roughly already written here above:
A particle curves SpaceTime, how does such a situation look like?
My reasoning is that if ‘Black holes’ are massive objects that create ‘holes’ in SpaceTime, than all lighter massive objects are also ‘holes’ but not black.
See SL's video at #36, you could say that mass pinches SpaceTime, the relationship to ‘hole’ comes more from the fact that matter ‘falls’ towards it, e.g. fall into a hole, a depression or in a valley.
There are enough conceptual images where the Sun forms a pit/hole in SpaceTime-plane, hardly any different that illustrations of Black holes except those point towards a singularity.
Using the term 'hole' for a massive object is about taking a deeper look at them instead of ‘simple’ point particles, also in relation to rippling GWs.
Ok then, if you are simply using the term "hole" to describe a curved region of spacetime, then sure, massive bodies create "holes" in spacetime. That's not particularly enlightening, though, since it's the essential content of general relativity. I do apologize; I thought you were trying to go beyond what GR says and claim something additional.
There is a quite significant difference between the curvature of spacetime near a massive body like the sun and that of a black hole, though, although the pictorial diagrams do not show it. Near a massive body, spacetime is indeed curved, as it is near a black hole. However, mathematically, there is a key difference. The coordinate described in rough terms as "distance from the center of gravity of the body" is a space-like coordinate near the sun (or any other ordinary massive body). That same coordinate near a black hole is no longer space-like, but rather a time-like coordinate. That distinction has a very precise meaning in the math of GR, but very roughly speaking it means that you can no more move in a direction that increases your distance from a black hole than you can move into a past time in ordinary spacetime. That would certainly seem to be a fairly key difference.
What you can do to break the glass, is *tick* the glass, record the sound and replay the sound at a high pitch and amplified, so the glass is softly pushed over and over again, absorbing all the energy until it snaps!
You're talking about something like constructive interference or a resonance frequency. But my point is still valid; if it occurs, we should be able to see a little bit of it when only a few particles interact that way. With sound waves for example, it is easy to detect resonance frequencies in things long before we break glasses. So why don't/can't we detect your resonance effect?
What is so magical about it that it doesn't function like every other resonance effect physics has ever observed?
That is a question you and your compatriots need to answer. Specifically, you need to provide a mechanistic, quantitative set of formulae which show why we should think this will happen.
But there are two other questions you need to answer: why do you think a proton 'snapping' is a risk? High energy reactions break them all the time. No strangelets or other exotic matter is formed. So it's not enough to just use a verb like "snap" and expect us to go along with your world-ending scenario. You have to tell us what this "snapping" entails that makes it different.
Another question you have to answer - and which gets bakc to both the nuclear fission and glass ringing examples - is that you are right and a big bunch of these waves have a big destructive effect on a proton, why don't we see any evidence that a smaller bunch of them have a lesser effect of the proton - moving it around or something? You see this in nuclear reactions. You see this in acoustic waves and glasses. Its simply not the case that such reactions produce no effect until they produce a catastrophic one; their effects are incremental, and we can observe them incrementally. So why isn't your hypothesized effect similarly incremental?
This is yet another example supporting my point and undermining yours. Rub two sticks together and a detector can see heat being produced long before a fire breaks out. It's an incremental process. All these processes are detectable at smaller scales - every single metaphor and example you've given have detectable signals long before the break/fire/nuclear explosion occur. So if yours resembles these things, it should have a detectable signal before the world ends too, yes?
Sean T @56:
This is why my 'starter equation' for MM has d[something]/dt in it; because I think if MM and others like him really try to think hard about what that 'something' must be, they're going to see it has to be everything. All nuclear interactions (because we use those as clocks). Al chemical interactions (we use those too). All mechanical motions (we use those too) - in every direction.Which is equivalent to saying time dilates, while being a lot more (and unnecessarily) complex.
eric #50: "“The effect of the longer train fitting into a short tunnel is explained in SR by the non-simultenaity of different frames of reference, not through a physical shrinkage."
This is a perfect example of the nonsense of SR. A 100 meter train can not fit into a 50 meter tunnel without shrinking the actual physical train from 100 to 50 meters. Mere differences in observers' perspectives and measurements can not shrink a solid steel physical train. (That's a fact.)
If Ethan and other hardcore physical length contraction advocates would just clarify (and change the textbooks to reflect) that LC is about hypothetical differences in images as measured by different observers... NOT PHYSICAL SHRINKAGE of objects or distances... then I would be happy and would shut up and go away. It is false, yet "standard science" ever since Einstein.
He said in 1938: ""Physical concepts are free creations of the human mind and are not, however it may seem, uniquely determined by the physical world."
So goes the philosophy of relativity!
Equations can not shrink physical objects, nor can the doctrine propagated by SR that "length is not invariant." It requires force to compact an object into a shorter length, not just observers seeing that object differently. And stars don't move closer together as "frames of reference" at near lightspeed travel between them. All the above must be plain enough to understand for any intelligent person who is not thoroughly indoctrinated with SR b.s.
"And what about your mathematical description of your idea? I.e. the idea that clocks slow down when they are accelerated. Do you have a mathematical description of that? "
We observe via empirical science that clocks at different speeds keep time differently. The doctrine of time dilation insists that time is a variable entity and that it's math reciprocal is length contraction. ("Therefore slow clocks make lengths contract,"... it's right there in Lorentz's transformational equations!) Yet time remains a concept for the duration of observable events... in units based on Earth's day and year (now very precisely standardized.)
So, it is a valid scientific question to ask what makes clocks slow down as timekeepers as they gain velocity via acceleration. I sure don't know the physics of it, but that is what we observe. The "explanation" that time is a variable entity which clocks "measure" (HOW?) is just standard SR doctrine, required to get physics credentials. We do have a clue that it is about exposure to force in that more force of gravity also slows them down.
Enough for now.
@Sean T #56:
" The earth’s rotation and the earth’s revolution around the sun both qualify as clocks. They also are both affected by the motion of the observer, just like any other clock."
Do you seriously believe that Earth's rotation and orbit are "affected by the motion of the observer?" If so you are delusional.* I can say this with professional confidence as a retired psychologist.
If your answer is "yes" then I will not waste anymore of my time with you.
*Same for those who believe that "the motion of the observer" can make the Earth flat in the direction of his motion.
Ethan: "How much mass do you plan on adding? Because the entire asteroid belt is 0.5% the mass of Mars. You want to bring Mars closer to the Sun? How are you going to dissipate all that orbital energy?"
I admit I didn't realize total mass in the asteroid belt was so small. But still there maybe a solution by stealing some moons of Jupiter etc (assuming we could have the energy/tech in distant future). :-)
"But my point is still valid; if it occurs, we should be able to see a little bit of it when only a few particles interact that way. With sound waves for example, it is easy to detect resonance frequencies …"
You are right, but it seems that you have missed the part where I wrote go look at my reply at #3, which is related to Ethan's comment. I'll c/p it here again:
"The point about ‘noise’ at the LHC was about being able to detect soft Gravity Waves produced during High-energy particle collisions. Of course the LHC is excellent at detecting and defining what comes out of these collisions, no question about that, but to detect soft GWs there is (probably) too much ‘noise’. Imagine placing the LHC next to LIGO, would LIGO still be able to detect and filter out GWs, probably not because the LHC produces too much ‘noise’."
The same goes for any other experiment that tries to measure how the Proton vibrates during particle collisions.
"This is yet another example supporting my point and undermining yours. Rub two sticks together and a detector can see heat being produced long before a fire breaks out. It’s an incremental process."
Again you are right. But it seems you also ignored an other paragraph I wrote, the last one in my previous reply to you. I'll c/p also that one here:
"One last point is let’s say that we can make one surrounding Proton snap, when surpassing a certain frequency and density threshold, than we wouldn’t be noticing it because we’re not able to process the data in realtime, so we’ll be continuing heating up billions of other surrounding Protons as well, not able to see the ‘smoke signals’."
@Sean T #58,
Thanks, and of course it's not 'particularly enlightening' I'm just investigating the path of seeing the LHC as an ignition and what's around it as fuel, the most classic phenomenon that mankind is able to produce. Simply taking into account the matter that surrounds the collision spot, a bit like how you describe the relationship between the Blackhole and what's outside of it. Their is no void, it's all connected.
I forgot to answer this one:
"why do you think a proton ‘snapping’ is a risk? High energy reactions break them all the time. No strangelets or other exotic matter is formed. …"
I have no interest in other 'exotic matter' to be formed, that's not relevant.
You could look at it more as an implosion. Let's say a Proton is shaken apart by ripples in SpaceTime and loses it's structure, this collapse causes for an implosion which sets of again a small rippling effect through SpaceTime on to the next Proton and so forth. So you start it off by a large amount of collisions once the surrounding area starts to collapse and ripple spread out the domino effect is set in motion.
We can't detect GW's because the sources we look at are weak (at least, by the time the waves hit the Earth). You are claiming high energy physics collisions produce ever-increasingly strong signals of them until the gravitational force is strong enough to tear protons apart. What I'm pointing out is that if you were right, we'd detect the effects of these waves building up long before it got to that point. Long before protons are torn apart, strong gravitational waves will impact the reaction products, the detectors, the ring itself. You mention protons "heating up." It is well within the capabilities of current science to tell excited ("heated up") protons from unexcited ones. We don't see these heated up protons - and our detectors are good enough to do so. Ergo, there is no build up.
To put it in your metaphorical terms, if you do somethnig to a stick and there is no heat produced at all, then doing more of it to the stick isn't going to produce a fire. You send an acoustic wave at a glass and the glass doesn't flex at all, more such waves aren't going to break the glass. You shoot a neutron at a nuclei and <1 neutron per reaction comes out, doing the same thing a million times will not cause a criticality event.
For this to be true you have to invent yet more unknown physics, because as I said above, right now we can tell when a proton is excited ("heated up").
To again put it in your terms, we understand this particular 'fire' and 'smoke' well enough to detect if there were smoke signals. We don't see any. So either there aren't any, or you have to tell us why we don't see what our detectors are perfectly capable of seeing.
This is just technobabble. Why should I look at it as an implosion when you have no quantifiable physics or mechanism involving forces or fields or other things, to show there is some reason to expect an implosion? Why should I expect said event to produce further gravitational waves of sufficient strength to tear apart the next proton? Do you have anything beyond "Chelle thinks it might happen" to back up this scenario? Any math that connects naked quark interactions to the production of gravitational waves?
If you assume simultaneity, you're right. But that's a Newtonian framework. Let's put doors on the tunnel to make this concept clear. In SR, the outside observer sees a time t in which the doors on both sides are closed and the train of length L is in the closed-off tunnel. The train-bound observer experiences the train as 2L in length - so at any time, some bit of it is sticking out of the tunnel, but also never experiences a time in which both doors are closed at the same time. If they compare notes, the outside observer says "at THIS time T both doors were closed," and the train-bound observer says "at NO time T were both doors closed."
Well, you need to propose some physics of it, if you want to overthrow Einstein.
You need to quantify your clue and then test whether that quantified hypothesis gives accurate predictions, in order to be doing science.
MM - "I can say this with professional confidence as a retired psychologist."
This tidbit also means you do not have the necessary credentials to expound on SR, GR, or any other R's with anything resembling authority as compared to those who have made it their life's work and are actual, bona fide experts in the field. Much like the fact that I'm not going to go to a physicist for therapy. You know, not qualified. Although I'm sure they have all kinds of opinions on psychology.
I'm sure there are many people who need psychologists who are glad you are retired. Your former career also explains your ignorance of science.
"You need to quantify your clue and then test whether that quantified hypothesis gives accurate predictions, in order to be doing science."
OK, here is my proposed experiment:
Put a clock in a centrifuge and wind it up to extreme G's. Have an identical control clock in the same lab.
See how much time the stressed clock loses per hour, day and month.
Examine the spinning clock constantly by all means for changes in structure and possible reasons for changes in oscillation cycle.
Do the same on human twins. Check for differences in rate of aging.
Write and get a grant from NASA to fund the experiment.
In my dreams.
How about you, Alan G.? Do you believe that an observer traveling at high speed can affect the spin and orbit of Planet Earth?
My passion for science was not my career but I've always been interested and kept up on new developments in my areas of interest, including relativity. Appeal to authority is for those too timid or stupid to think for themselves.
said that he plugged in numbers into the quadrupole formula, and there is nothing published because a one-minute calculation shows it is tens of orders of magnitude too weak to be relevant.
"What I’m pointing out is that if you were right, we’d detect the effects of these waves building up long before it got to that point."
With which measuring tool. For the glass we needed the high-speed camera to see it wobble, what tool have we got to keep an eye on the Protons?
BTW can you point out to a source that the LHC is analyzing these collisions in realtime.
And it's not 'technobabble' you need a lot of energy to create a particle, just like lifting a rock up a hill to generate potential energy, drop the rock and you'll feel the earth tremble, implode the Proton and SpaceTime will ripple.
Note, didn't the energy of the BigBang go into the creation of particles incl. Protons?
MM - How about you, Alan G.? Do you believe that an observer traveling at high speed can affect the spin and orbit of Planet Earth?
There are countless instances in science, math and engineering where a concept is counter-intuitive, but is still true. It's impossible to gain credibility by making claims in a comment section on a blog. I have a basic understanding of these concepts in principle, and they are consistent in principle with what I've seen elsewhere by people who are in a position to know. There are details I don't yet understand. Not understanding is not equivalent to "it must be wrong".
Your experiment must distinguish between your hypothesis and SR, not your hypothesis and 'no effect on clocks'. Since SR would predict dilation in a sufficiently fast moving (end of a) centrifuge, as written your test is no good. However if your hypothesis predicts that different types of mechanisms are affected differently (i.e. some clock will go slower, another won't), then yes we could test that. Likewise if your hypothesis predicts that organisms won't age any differently than in a rest frame, that would be difficult to test but we could probably do that.
But the naive test of "when it spun the clock slowed down" would not be evidence of your idea being right, since SR predicts that exact result too.
A gravitometer. Heck, pretty much anything. I don't think you understand the dynamic range of the g-forces you are claiming will build up. A 1 kg mass in the LHC would be moved by your build up of gravity waves when they are still roughly 0.000,000,000,000,000,000,000,000,1% the strength you would need them to be to influence a proton.
blockquote>And it’s not ‘technobabble’ you need a lot of energy to create a particle, just like lifting a rock up a hill to generate potential energy, drop the rock and you’ll feel the earth tremble, implode the Proton and SpaceTime will ripple.
'Many imploding protons will create gravity waves with sufficient force to implode more protons' is indeed technobabble. Because you have no evidence any such thing could occur. Because you have no quantified theory as to how or why it could occur. And because actual protons when actually taken apart into their constituent quarks don't "implode" at all.
What you have is a set of metaphors which you believe apply to physics without any evidence that they are even relevant. These metaphors invoke reactions we don't observe, using unknown mechanisms which you won't explain. And on top of all that, you even get the metaphors wrong in terms of what they would imply. Sure, you're not making up new words (another aspect of technobabble), but "the proton reaction is like a [something]" when you have no good experimental or theoretical basis for making that comparison is just babble. Your 'a proton is like a wine glass' is not any more meaningful or valuable to science than 'a proton is like a fish." Without some real observations or theory to back them up, they're both equally nonsensical.
"A gravitometer. Heck, pretty much anything. I don’t think you understand the dynamic range of the g-forces you are claiming will build up. A 1 kg mass in the LHC would be moved by your build up of gravity waves when they are still roughly 0.000,000,000,000,000,000,000,000,1% the strength you would need them to be to influence a proton."
LOL, what nonsense.
Think of a microwave oven that works with dielectric heating, shaking up molecules; and someone advises you to use a 'gravitometer' to measure the temperature of the heated up water inside the machine.
@eric #77: "But the naive test of “when it spun the clock slowed down” would not be evidence of your idea being right, since SR predicts that exact result too."
You selectively ignored the whole point of the experiment:
"Examine the spinning clock constantly by all means for changes in structure and possible reasons for changes in oscillation cycle." (Whatever type of clock is used.)
The point is to test the specific effects of G-force on the internal dynamics of the clock. We already know it will slow down. But SR insists that "time itself" slows down. What exactly IS "time itself? as an entity that slows down and speeds up? We observe that clocks do that. That is empirical science without the assumption that time is a thing that clocks "measure". Again, how? They just tick at variable rates.
Once the mechanism of its slowed down internal dynamics is better understood as a function of amount of force (simulated gravity) applied, the falsehood of claiming that clocks "measure" the slowing down of "time" will be exposed.
The human subject in part two would also be monitored by all possible means for changes in internal dynamics as a function of the G-force to which he is exposed.
Seems like those seriously interested in investigating "time dilation" would be all over this experiment or one like it. But there is no interest, because "time dilation" is considered an established fact (Einstein said so!) even without an explanation of what time is that clocks can "measure it."
@Alan G. #76
"There are countless instances in science, math and engineering where a concept is counter-intuitive, but is still true."
So... you didn't answer my question. Is this one of those instances? " Do you believe that an observer traveling at high speed can affect the spin and orbit of Planet Earth?"
Afraid to question authority by any chance?
MM - "Afraid to question authority by any chance?"
There is no universe where screeds in a science blog's comment section constitute "questioning authority". I do ask questions about things I can't reconcile myself to people who have the required knowledge and skill set.
So, in "your universe" (each has their own?) I am not questioning authority because it doesn't count in a science forum. Not enough "authority" involved to make it a serious challenge, I presume.
And you continue to refuse to answer the question (#86). Maybe you are afraid to look foolish. No worries about that. Sean T. already opened that door:
@Sean T #56:
” The earth’s rotation and the earth’s revolution around the sun both qualify as clocks. They also are both affected by the motion of the observer, just like any other clock.”
And the whole philosophy of science behind SR is the foolish belief the nature and properties of the physical cosmos (lengths, distances, passage of time) are variable as determined by observational differences, all frames of reference being "equally valid."
Ps: I'm adding eric to the list of those so brainwashed by SR as to believe that a flat Earth is equally valid.
Me: It (Earth) obviously can not be both spherical and pancaked. It’s one or the other.
eric: "Sure it can."
Ethan agrees. He said that it depends on whom you ask.
Me: But SR claims that a 100 meter train will physical fit into a 50 meter tunnel. That can not happen without (bogus) physical shrinkage of the train.
Yes, it can.
How do you know that the one is 100m and the other 50m? Because if they are both measured in the same reference frame and 'standing still' then SR won't make that claim. You are leaving a lot of the details out and not giving us all the information that's not an honest way of arguing, you are lying (to yourself) by omission.
@ Michael Mooney
"... is the foolish belief ... all frames of reference being “equally valid.”
You probably don't realize it, but you seem to have more issues with Galileo then you have with SR. Focus on that first before threading in directions beyond it. Someone mentioned a ping-pong on a train.. great example. Think on that and forget speed of light for the moment and length/time dilation.
SR stands on solid ground. It doesn't work without Maxwell, without Lorentz etc... So you first need to prove that Galileo was nuts and wrong, then show how Maxwell was nuts as well in using Lorentz to facilitate ideas of invariance and EM. And only then do you get to tackle SR. So basically show beyond reasonable doubt that 400+ years of research are plain wrong. Thinking that SR is in some sort of vacuum and unconnected with other things in physics is another wrong assumption.
I didn't make this crap up.
"We have a tunnel 800 feet long in its rest frame... The train is 1,000 feet long in its own rest frame, ...
The train travels at speed 0.8 c so that its Lorentz-contracted length allows it to fit entirely inside the tunnel.
If the 1000 ft train travels at 0.8c it will fit into the 800 ft tunnel. This is the standard "train-in-a-tunnel paradox" (bullshit.)
Obviously the difference between what observer A and observer B see does not make the train physically shrink, as required for the above "fit."
edit: end quote after tunnel"
Read the first paragraph of that side and look what I have made fat:
Now look at what I wrote, and what I made fat:
See the difference?
Sinisa Lazarek: "And only then do you get to tackle SR."
I get to tackle SR whenever I damn well please, even without your permission.
All I ask here is the disambiguation of the difference between apparent contraction and physical contraction.
Ethan most recently claims that observed micro-particle compression/ contraction via extreme acceleration applies to macro-objects (like a 1000 ft steel train.) Let's also apply it to the distances between stars and the diameters of planets as measured by very fast travelers. All of that is a bogus claim by SR that objects and distances actually physically shrink as a function of relativistic frames of reference.
Do you see the difference between apparent contraction, depending on frame of reference, and physical contraction?
If so please explain it to Ethan, Wikipedia, and all universities using the standard textbook version of SR.
Answer my question first.
I know the difference between "proper length" measured from at rest with an object and SR's bogus argument based on the "relativity of simultaneity," wherein all dimensions depend on frame of reference. Ok?
you misunderstand my wording. Of course you don't need permission. What I meant is that only when you have sufficient knowledge of the fundations can you tackle SR in some meaningful way. Without prior knowledge and understanding you're only showing your own ignorance of subject.
But that aside, like I wrote in #86. SR is not standing in vacuum. Tackle galileo, maxwell and lorentz first. Show why galileo is wrong if you please, then show us how maxwell got it all wrong, and lorentz, and let's then go to SR.. no fast forward.
You haven't answered my question, you have now dodged it twice, answer it.
Please explain. More detail and reference points would be very helpful to explain *your question." Which one? A comment number would be helpful for easy reference. But you seem to like cryptic references. Count me out or answer my SR challenges... which I've made very clear here as best I can in service to truth in science (without personal bias.)... Yes, is possible.
Start with the Flat Earth measurement and then the changing distances between stars, and then get on down to long trains in short tunnels.
Try to make sense, even if it is "common."
Do we each create our own "reality?" (Sorry, too philosophical.)
Have a great day!
No I won't, you need to find the answer yourself, or ask a friend to help you out, and come back when you have an answer.
Paul Dekous #89: "See the difference?"
#92: "Answer my question first."
I know the difference between “proper length” measured from at rest with an object and SR’s bogus argument based on the “relativity of simultaneity,” ...
PD #95: "You haven’t answered my question, you have now dodged it twice, answer it." (See #93 and #95): "Which one?"
Are you going to pout like a child or recognize the difference between proper length (actual physical length) and differences in relativistic observational perspectives? (Rhetorical question.)
Seriously, who is dodging questions here. See #96:
"Start with the Flat Earth measurement and then the changing distances between stars, and then get on down to long trains in short tunnels." (Real steel trains in solid concrete tunnels... like in the real world.)
Not interested in real world science? Then keep on pouting.
MM - "Not interested in real world science?"
Do some actual science in the real world and then you can comment about real world science with some measure of credibility. So far all you have to your credit is the pleasing sound of your keyboard clacking, and that seems to be all you intend to do. Look up the word "poser" in the psychology literature.
Nobody is doing it now because a test like what you suggest was done in 1913, by a pair of scientists named Wilson and Wilson. The results agree with relativity.
You keep claiming in posts that we must pay attention to experiment. We do. All the experiments done to test SR show that it is correct. In claiming it is wrong, it's you who are ignoring empiricism and experiment.
But of course you and I know this, don't we? Because months ago you told me that if muon measurements are consistent with time dilation, those measurements must be wrong. Faced with evidence that contradicts your pet idea, and forced to chose between them, you choose to ignore the evidence and keep your idea.
Well you'd have to be moving very fast for a flat earth description to be accurate. And there is no single reference frame in which the two models are equally valid. But yes, if your point is that I accept relativistic predictions, that's true. Because experimental data supports that theory and contradict the hypothesis that time and space are Newtonian.
As far as scientists are concerned, what you are doing is not "tackling it" at all. Anyone can verbally claim some scientific theory is wrong. "Tackling it" requires developing an alternative, testable hypotheses. And testing it. And publishing the results. And having them stand up to criticism.
It seems to me at this point pretty obvious you have no real quantifiable testable hypothesis. You have no math.
Even worse, you won't even make the effort of understanding the math that's already there .When I pointed out that SR says L=L0/gamma and thus NOT that either L or L0 changes with t, you don't address the point. You either can't or won't address a simple three term equation!
This has been explained to you many many times. The contraction is neither merely apparent nor is it a physical change caused by the motion. You are making a false dilemma fallacy in thinking those are the only two possibilities. The actual explanation - the 'third possibility' - is that these are quantities that are relative to ones' frame of reference. Just like a cannonball's momentum can be 0 kg*m/s to a person in one frame of reference and 100 kg*m/s to a person in another. Now if I start running next to a moving cannonball, my movement doesn't cause a physical change in the cannonball's momentum. But neither is the new, different momentum I would experience in hitting it merely "apparent." It's real. My body will feel real effects of the momentum I measure in my frame of reference, and not an effect that would be consistent with the cannonball's momentum as measured by an observer in a different frame. It's just that momentum is a relative quantity. And in SR, the passage of time and the measure of distance are also relative quantities. The quantities are really different to observers in different frames of reference, and yet changing your speed relative to an object does not cause any sort of physicochemical change in that object. Because the quantities are relative.
Finally, as a follow-on to MM's "nobody's testing it because we all blindly accept relativity" baloney, I'll note that Chou et al. recently made news testing SR by observing two atomic clocks, one unmoving in the lab frame and the other moving in a harmonic motion relative to the lab frame. At an oscillation speed of ~22.4 miles/hour (which is incredibly low; thus the reason they made the news). Now, harmonic motion isn't going around in a circle, but it's pretty similar.
And guess what MM? Their results confirmed SR. Again. Einstein's theories aren't blindly accepted; they are tested by experiment and empirically demonstrated to be accurate. You choose to ignore these results while ironically demanding that everyone needs to pay more attention to experimental results.
eric: "And guess what MM? Their results confirmed SR."
We have been over this many times before.
Read my experiment again. I have no problem with accelerated clocks slowing down, as I've explained many times. The problem is with the assumption that clocks "measure" a variable entity, time. How is that supposed to work, other than altered rates of ticking (no doubt)?
Remember my example of true measurement via thermometers measuring temperature. What is the mechanical explanation of clocks measuring time?
Btw, the Earth's motion is still the best standardization of time for Earthlings, even if atomic clocks should be tweaked a bit as spin and orbit vary ever so sleightly... Nothing like high speed or high gravity instrument variation.
(And we need a master clock at sea level on the equator.)
You say their results confirmed SR, but what all such results confirm is that the tested clocks slowed down. Don't ask why. Just assume that time is a thing, like space... and together... what a "glorious non-entity" as praised by the physicists/ mathematicians Brown and Pooley.
Let's go time traveling through the "timescape" since it's no longer just science fiction! I want to visit the time of living dinosaurs and then the soon-to-be Mars colony... now!
t = t0/gamma is how it's supposed to work.
Every physical, chemical, and biological reaction or interaction is affected. From quarks to quasars. You seem to think the word 'clock' refers to some sort of object-type that is affected by relativity differently from other objects, but a clock is simply a series of physical or chemical interactions that have a predictable cycle. And all such things are affected by relative velocity - not acceleration.
We ask why. The 'why' is that time dilation is an inevitable and logically deductive consequence of (1) physics worknig the same way in different frames of reference, and (2) light always traveling at c in a vacuum. If those two postulates are true, time dilation must be true. Time must be a relative quantity.
And as far as I can tell, you don't claim either postulate is false. You don't claim the math is false (actually, you don't seem to concern yourself with math at all). You just reject the conclusion out of incredulity and don't bother refuting any of the actual foundation on which it's based.
Secondly, experiment show far more than just clocks slowing down. Experiments at RHIC are consistent with accelerated particles hitting a relativistically flattened target, even if it's not flat in our frame of reference. Muon lifetimes (again) are consistent with time dilation and foreshortening in their frame of reference.
Nobody tests merely clocks. We test all sorts of things - some of which can be used as clocks, but not just them. And all things, all, show results consistent with relativity.
MM - "Let’s go time traveling through the “timescape” since it’s no longer just science fiction! I want to visit the time of living dinosaurs and then the soon-to-be Mars colony… now!"
Man, I hope you had a better grasp on psychology than you do on this. Or, I hope you are really conducting a case study on the psychology of the internet.
eric: ' And all such things are affected by relative velocity – not acceleration."
How do you know that they are not effected by acceleration since they must be exposed to the force of acceleration to reach different velocities?
You make the statement as a given fact, ('The Doctrine") ignoring each clock's history.
My invitation to go time traveling was sarcastic, in case you missed it.
Ethan thinks that time travel into the future is possible but not into the past. (Just his personal belief, which has no place in science.)
As I've told you before, atmospheric muons are produced at a relativistic velocity (in relation to the Earth). THey never undergo acceleration. And they show relativistic effects.
The broader, more important point, however, is that in science if you want the community to accept an alternate hypothesis it's up to you to quantify it, test it, and show the results. If you want anyone to accept that acceleration causes it, it's up to you to quantify what your hypothesis says and show how the data supports your hypothesis better than SR. The particular sticking point I see with your idea is that it requires every particle in the universe to know it's "history" of being accelerated. What property of particles records that information? And how does it interact with the physical properties we know about?
To get back to the doctrines you recited (over and over) re:
".. physics worknig the same way in different frames of reference, and (2) light always traveling at c in a vacuum. If those two postulates are true, time dilation must be true. Time must be a relative quantity.
And as far as I can tell, you don’t claim either postulate is false."
Most critics of relativity, myself included, do not accept the dictum that different frames of reference all describe the real physical world accurately but differently. So, instead, try this:
Physics works the same way throughout the physical cosmos, regardless of relative perspectives and disagreeing observers. There is no physics of physically shrinking objects via differences in observation... no empirical verification or demonstration.
Second, the constant speed of light in a vacuum does not require that objects or distances shrink just to accommodate the Lorentz doctrine of transformed dimensions. But none of the critical arguments against that doctrine are taken seriously since the rule of observer-based changes in physical length took over physics as SR.
Of course "time dilation" advocates will not even consider the question of what time is as a measurable entity. ... no matter how the question is asked. But it "dilates" anyway,
" Muon lifetimes (again) are consistent with time dilation and foreshortening in their frame of reference."
If "their frame of reference" made the atmosphere vary in depth/ thickness, atmospheric science would have abundant evidence from measuring such variations all over the planet as incoming muons altered atmospheric depth.
I once cited a critical analysis questioning the methods of measuring muon half lives (in lab muons as compared to atmospheric muons) and how they count the ones that "shouldn't reach the ground," in their "allotted time" but of course it was immediately dismissed as "just another relativity crank."