"It appears, from all that precedes, reasonably certain that if there be any relative motion between the earth and the luminiferous ether, it must be small; quite small enough entirely to refute Fresnel's explanation of aberration." -Albert A. Michelson
In the 1880s, it was clear that something was wrong with Newton’s formulation of the Universe. Gravitation didn’t explain everything, objects behaved bizarrely close to the speed of light, and light was exhibiting wave-like properties. But surely, even if it were a wave, it required a medium to travel through, just like all other waves? That was the standard thinking, and the genius of Albert A. Michelson was put to work to test it.
The Earth, moving in its orbit around the Sun and spinning on its axis, should provide an extra motion if there's any medium that light travels through. Image credit: Larry McNish, RASC Calgary.
Because, he reasoned, the Earth was moving around the Sun, the speed of light should get a boost in that forward direction, and then have to fight that boost on the return trip. The perpendicular direction, on the other hand, would be unaffected. This motion of light should be detectable in the form of interferometry, where light was split into two perpendicular components, sent on a journey, reflected, and then recombined.
If you split light into two perpendicular components and bring them back together, they'll interfere. If you move in one direction versus another, that interference pattern will shift. Image credit: Wikimedia commons user Stigmatella aurantiaca.
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Mass is NOT converted into energy, you misled , misinformed fool. There does NOT exist a complete equivalence between mass and energy. E=mc2 is not even true. It's pop- culture /pop ---science nonsense......What is true is Eo=mc2 for objects sitting still.
Mass is a Poincare scalar and it is always the SAME in different reference systems. Energy is the fourth component of a four vector and is DIFFERENT in different reference systems. When we have mass, we indeed ha e energy. However, you CANNOT-CANNOT reverse this statement! The opposite is NOT true.
Einstein's great discovery was the rest-energy.
Another great error is the claim matter is converted i to energy. No! Only particles areever transformed into one another. Energy is NOT stuff-at all. It is a property, purely mathematical. Matter is actual STUFF. Photons, while not matter, are DEFINITELY STUFF-They are NOT energy. THEY ARE PARTICLES-STUFF. OBJECTS. Matter and energy are NOT related.
Sincerely,
Jane Palubenskas
Neil Tyson butchered E=mc2....... His explanation is beyond laughable (Kaku's, Green's, Cox's and Nye's are laughable as well!) The ONLY energy being put equal to mass is the REST-ENERGY -ONLY!
Sagan, Tyson, and the rest of these hokey science popularizers were BUFFOONS. Lev Okun was a REAL scientist and KNEW this topic.......
"E=mc2" is the result of Einstein getting sloppy in his writing , failing to "dot all the i's " - and the media latched on.
E=mc2, written that way, is WRONG.
The ORIGIN of the universe is NOT CURRENTLY known by any physicist, you fool. Sagan, Tyson and other buffoons spread misinformation.
No serious scientist has concluded that the Big Bang was the start of it all, despite the nonsense you hear by the hokey science popularizers...... The common version crap you hear from Sagan and Tyson - "The Big Bang" lore , is too far removed from anything we have experience with and is MUCH MORE than we ACTUALLY know.....
Again, the ORIGIN of the universe is NOT known. I have TOP sources.
Sincerely,
Jane Palubenskas
Your second diagram is flawed. Here we see the vertical photon is moving with the source when Einstein said that the speed of light is independent of the emitting body - a clear violation of the Einstein's 2nd postulate.
Secondly, in the both diagrams, the photon maybe flowing with the aether in one direction; but is fighting against it on the return journey. These effects will cancel out and you'll get a null result.
But, in the second diagram, the source is moving, I hear you say. But the whole apparatus is moving: the reflecting mirror is moving away from the source thus it will take the photon a little longer to reach it. On the return journey, the detector is moving towards the photon, so it'll take a little a little shorter time to get there. These effects will also cancel each other out leaving a null result.
All that the MMX proved was that the speed of light is independent of the motion of the emitter which Einstein adopted into his theory. Perhaps you're showing what Michelson and his compatriots (Lorentz and Fitzgerald) expected.
Lorentz and Fitzgerald incorrectly assumed a non-null result for the moving apparatus and thus postulated a shortening of the length in the forward direction to explain the null result. But this correction was to their false assumption. This led to time dilation as well. Because Einstein adopted the Lorentz factor into his theory of Special Relativity, it has been tainted by this fallacy.
Then Einstein applied the Lorentz factor to mass and concluded that it must increase with velocity. When he found that this wasn't the case, he told everyone not to use relativistic mass. If it doesn't work for mass, it wouldn't work for length nor time either. Ironically, these entities are the M, L, T dimensions. If L is the spatial dimension and T is the time dimension; what dimension does M represent?
As I've always said, science is about definitions but this time, it's about interpretation of results as well. The Lorentz factor is based on a false assumption; hence, it's also false and so is anything based on it. This false assumption is due to the assumption that the photon moves with the emitter which is a Galilean principle.
@Ethan,
You subscribe to DM and DE, but only where we can't measure it outside the influence of our local gravitation field, so why do you think the Michelson Morley experiment proves anything by that same criteria? Wasn't the ether supposedly dragged along in locality in a similar way which would have required the test to be conducted outside of nearby locality (away from the planet) to detect it?
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Strange that you should bring LIGO up. Considering that in order for LIGO to work, light would apparently not be affected by space while matter would be. LIGO is entirely the proposition that matter (the earth) could be warped/compressed/whatever due to space ripples, while light would not be similarly affected and could be used to reliably measure such claimed distortion (the required measurement precision was utter bullshit, even with interferometry, but for the sake of your argument I'll let it pass). Considering how you personally subscribe to the idea that gravity lensing of light around stars is true, I'm not really sure what leg you think you are standing on. You can't have it both ways.
I think you're mistaking the crux of SR for a violation of it. We, outside the table, observe that photon traveling at c. We do not observe it going faster than that merely because we observe it traveling a longer (and 'sideways') path. A person sitting on top of the beam splitter on that moving table would also see that photon traveling at c. So Einstein's second postulate is not violated; everyone sees the photon traveling at c, independent of the source.
The fact that observers in both frames of reference see the photon traveling at c - the fact that observations confirm Einstein's second postulate - even though they measure its path and path length differently, is what leads to the requirements of time dilation, foreshortening in the direction of motion, loss of simultaneity, and so on.
According to mainstream physics AIUI, DM and DE do not stop at our local gravitational field. That's a position or implication you have invented yourself and then strawmanned onto the mainstream. Your claim is analogous to someone claiming biologists subscribe to germ theory but think germs only exist on microscope plates. They obviously don't. That would confuse where we point our instruments with where we think they exist. Likewise, you appear to be confusing where we point our DM detection instruments with were we think DM exists.
@eric,
Ok eric, I wasn't addressing you, but if you want to chime in...
Where's the beef, literally?
You claim DM/DE is everywhere?
Then why isn't our solar system expanding? Or our galaxy expanding? Or the space between your ears growing? Please stop with the crap explanation that it actually is expanding but only by some ridiculously small but unmeasureable amount through a calculated inference based on nothing. Anyone can throw out wild ass guesses in scientific notation, that doesn't make it science.
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The fact is, neither YOU or anyone else has come up with a working (testable) theory of what dark matter/energy is, or been able to locate it (much like the ether) nor has any definite understanding of it's imagined properties been worked out since its makeup is nothing but a great big data hole you paste the word 'dark' in front of and claim to understand. 'Ya got nothin'.
Enough with what you think I do or do not believe in outside of the topic of discussion you ignorant twit. Pie in the sky cosmology is not even close to being analogous to an actual applied science like laboratory medicine. Barring your as yet undisclosed admission of omniscience, you literally have no idea what I know or think about microbiology. For the record I happen to respect laboratory medical science (as it lifesaving and highly useful) FAR more than fluff cosmology, theoretical or HEP physics (as it full of male ego stroking gits and next to useless outside of academia). My mother also is a retired pathologist and medical technologist so I know a few things about pathogen screening and transmission vectors. If you were looking for a strawman argument, you really stepped in the manure on this one.
If you think you do know what/where DM/DE is, please be a luv and publish a precious paper, they surely have a nobel prize with your name already engraved on it...right next to Michael Mann's. The folks at the LHC are also waiting with bated breath for your enlightened revelation as "where to point OUR instruments where WE think they exist" as it would make their lives so much easier if they actually knew what they are specifically testing for. It's quite telling (this would be the male ego stroking part) you actually think of yourself inclusively as a member of the HEP community.
"Then why isn’t our solar system expanding? Or our galaxy expanding?" This is because there is a self-correction of distance between objects going on for gravitationally bound objects in orbits and similar situation with orbits of electrons (is it called electromagnetically bound?) in atoms.
It is amazing that some people think something well proven like expansion of universe can be disproven so easily. You seriously think physicists of the world would not see such simple issues if there were? Would not try to defeat the expansion if it was really that easy? Or do you trying to imply they know it but hide it from the public?
Or you want us to think scientists accepted expansion of the universe without really good proof? Do you know how all scientists believed steady-state theory of universe for a very long time? Do you think they gave up so easily?
Are you trying to imply you are smarter than all physicists in the world? if so I think it is clear the opposite is way more likely.
I think it’s inaccurate to say Ethan et al. have nothing. While both require special pleading (http://scienceblogs.com/startswithabang/category/dark-energy/ , http://scienceblogs.com/startswithabang/category/dark-matter/ ) to be incorporated into either the Standard Model or General Relativity, there is evidence/observations that each attempts to describe, if not yet to explain.
Am an artist interested in science, but was very dismayed at the comments made be educated people against the author, and against the science celebrities, none of whom were lightweights as scientists. The name calling was childish. Stop and think. Science in this country is in serious trouble. We are all on the same side. Act like responsible adults. We get enough of the name calling from the anti-science GOP.
Ethan deserves to be treated respectfully. He provides enlightening and thought-provoking articles every day. He presents the mainstream view of science, tailoring his writings to be understood by reasonably intelligent readers from widely-varying backgrounds. Though well educated himself, he frequently checks with experts to make sure he's presenting information on complex and subtle topics "just right."
In short, he works hard at his job and we benefit.
He hosts this blog for us to talk among ourselves and with him. Though valuable, it's here for us for free! He's been respectful of us, his readers. Though he can do whatever he wants with this blog, he's allowed us to largely say whatever we want.
He's respected us; he deserves respect in return.
We posting here on his blog do not provide a tenth of a percent of the value that Ethan brings. None of our contributions are "worth" abusing him.
Behave like adults. When you disagree, tell us what you think is wrong and right. Ethan can't avoid errors in fact or poor wording occasionally - mistakes come with our DNA. But be respectful.
When you post rude comments, it reflects only on you. You influence nobody, except to help them dislike you.
It seems the Internet also abhors a vacuum. One rude and hostile poster leaves, and others move in to fill the void.
Done with social stuff for the moment, science question here:
How much energy is lost or gained by orbiting planets to correct for the expansion of space between them and their star?
Does that even happen? Seems like it should.
Space expands, "pushing" the Earth away from the Sun. Eath gains potential energy. But the Earth slips back to it's original orbit, or very nearly does, through common orbital mechanics. Is there any transfer of energy (e.g. DE to potential energy)?
I'm aware that expansion is tiny now, but it hasn't always been so. I'm wondering if the effect is measurable in theory, 'cause that would be really cool!
This has been explained to you (over and over again). I'm not expanding for the same reason gravity isn't causing me to fall through my couch; because other forces counteract its effect. DE is an extremely weak effect on the local scale, very easily overcome by the EM force that holds my molecules etc together.
Do you understand that? Do you agree with it?
AIUI, DM is all over the place,but not detectable everywhere. Here is where I think I know it's been detected. Do you have an alternative explanation for this observation?
Carl:
It's negligible. The 'pressure' to expand is measured by the hubble expansion rate, which is about 72 km/s per megaparsec of distance between two objects. If I did all my unit conversions correct, that works out to just about 1.1 cm per year per AU. That amount of push is likely to be completely 'in the noise' given the other gravitational pulls on the Earth from various objects.
@eric,
Just no. Dragging EM into the discussion just muddles it further.
You have nothing. Unit conversions or no, If your signal is not detectable from noise, you have no signal, just noise. This is because in SCIENCE for you to claim something is there, you need to actually be able to test and detect it, feelings and warm fuzzies will just not do, only evidence will do. First you need to find your needle in the haystack, try not to let the dog eat your homework, then you have something to talk about.
@Frank,
Scientists (Ethan included if you think he is one) are no less likely to delude themselves than anyone else. If this were not so, I don't think the father of QED would have said:
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"The first principle is that you must not fool yourself and you are the easiest person to fool."
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Feynman was a very smart guy, and he wasn't talking to the garbage man or his auto mechanic or a politician when he said this. He was talking about himself in a honest moment of humility. He also called it his First principal, not second or third on his list. Care to take a guess as to why?
P.S. IQ is not a meter for truth or correctness.
Very smart people are often insecure and prone to groupthink/herd behavior with people they think are their intellectual peers, they think it protects them from looking stupid or being wrong, both of which they are usually terrified of.
So you are claiming if expansion of the universe cannot be detected in atomic level that means it is not exist.
Which part of self-correction (of electron orbits) in atoms (due the electromagnetic force) you do not understand?
You are claiming physicists accepting things without good proof and yet you want people to accept your claims on your word alone?
Jane, you kick ass.
CFT
We do detect DE, as the expansion between distant galaxies and clusters. We detect DM via gravitational lensing around galaxies and clusters. We do not detect either on Earth simply because we don't have the instrumental ability to detect the signals either would produce at small local ranges.
And the "why doesn't it pull me apart" question can be answered practically by a qualitative understanding of high school physics. You have a mass with two forces acting on it: one exerts X newtons on the mass pushing it leftward. The second exerts Y newtons pushing it rightward. When X >> Y, why don't we ever see the mass move right? If we wait long enough, can we watch the mass slow down its leftward movement, stop, and then start moving right? Answer: no. We will never see it move right and Y never overcomes X, so long as X >> Y. In exactly the same way, the effective forces holding atoms together in molecules >> the force of DE expansion between those atoms. So DE will never break molecular bonds, as long as this is true. In fact, the force between atoms in a molecule >> the gravitational force between me and the Earth >> the gravitational force between Andromeda and the Milky way >> DE 'force' (for you're right, we don't really know what it is, only that it acts like a pushing force) pushing things apart. It's so weak, it's really only going to push apart things that are not bound together via one of the four fundamental forces. Unless it grows stronger; it that case, physics would predict an eventual 'big rip' type of end to the universe, where it does pull first gravitationally bound objects, then electromagnetically bonded objects, then eventually nuclear bound objects, apart.