"The joy of life consists in the exercise of one's energies, continual growth, constant change, the enjoyment of every new experience. To stop means simply to die. The eternal mistake of mankind is to set up an attainable ideal." -Aleister Crowley
But the Universe itself experiences continual growth, constant change, and new experiences all the time, and it does so spontaneously.
And yet, the better we understand our Universe -- what the laws are that govern it, what particles inhabit it, and what it looked/behaved like farther and farther back in the distant past -- the more inevitable it appears that it would look just as it appears today.
On the largest scales in our observable Universe, matter clumps and clusters together in a filamentary, web-like structure, while the densest parts form galaxies, stars and planets in isolation, in groups, and in clusters as appropriate.
Although different regions of space and different simulation runs will have slightly different details, the pattern of clustering is always the same; if we were to go as far back to the beginning as our physical understanding allows, we would get a Universe indistinguishable from ours in all but the most minute details 100 times out of 100.
By time the Universe is as old as ours is -- 13.8 billion years -- it will look exactly the same every time in so many important ways:
- It will have the same number of galaxies, of the same mass, clustered together in the same ways,
- The ratios of the elements in the Universe will be identical, overall, to the elemental abundance today,
- It will have the same number of stars and planets with the same mass distribution as our Universe,
- It will have the same ratio of dark energy, dark matter, normal matter, neutrinos, and radiation as our Universe,
- and, perhaps most importantly, all of the fundamental constants will have the same value.
This last one is so important, because starting with the same rough initial conditions is what guarantees our Universe will look the way it does. But what are these constants?
You might be used to constants like c, the speed of light, h (or ħ), Planck's constant, and G, Newton's gravitational constant. But these constants are dimension-ful, meaning that they depend on the units (e.g., meters, seconds, kilograms, etc.) you use to measure them.
But the Universe, very clearly, doesn't care what units-of-measurement you use! So we can create dimensionless constants, or combinations of these physical constants that are simply just numbers, numbers that describe how different parts of the Universe relate to one another.
We'd like to describe our Universe as simply as possible; one of the goals of science is to describe nature in the simplest terms possible, but no simpler. How many does of these does it take, as far as we understand our Universe today, to completely describe the particles, interactions, and laws of our Universe?
Quite a few, surprisingly: 26, at the very least. Let's take a look at what these are.
1.) The fine-structure constant, or the strength of the electromagnetic interaction. In terms of some of the physical constants we're more familiar with, this is a ratio of the elementary charge (of, say, an electron) squared to Planck's constant times the speed-of-light. At the energies of our Universe, this number comes out to ≈ 1/137.036, although the strength of this interaction increases as the energy of the interacting particle rises. This is thought to be due to a relative increase in how elementary charges behave at higher energies, although this is not yet a certainty.
2.) The strong coupling constant, or the strength of the strong nuclear force. Although the way the strong force works is very different and counterintuitive compared with either the electromagnetic force or gravity, the strength of this interaction can be parametrized by a single coupling constant. This constant of our Universe, too, like the electromagnetic one, changes strength with energy.
3-17.) The (non-zero) masses of the fifteen fundamental standard model particles with a rest-mass, relative to a fundamental scale set by Einstein's gravitational constant. (This way, no separate constant is needed for gravitation.) In the standard model, this typically manifests itself via fifteen coupling constants (to the Higgs field) for the electron, muon and tau, the three neutrino species, the six quarks, the W and Z bosons, and the Higgs boson. (If you preferred a different parametrization, you could replace the W-and-Z masses with the weak coupling constant and the Higgs field's expectation value; your choice.) The photon and the eight gluons don't get one, being intrinsically massless particles.
This is, I'll note, a source of much distress for theorists, who hoped that these constants -- the fundamental masses of the elementary particles -- would either be part of some pattern (they're not), calculable from first principles (they're not), or would emerge dynamically from some larger framework, like a GUT or string theory (they don't).
18-21.) The quark mixing parameters. These four parameters dictate how all of the weak nuclear decays happen, and allow us to calculate the probability amplitudes of different radioactive decay products. Because the up, charm and top quarks (as well as the bottom, strange and down quarks on the other hand) all have the same quantum numbers as one another, they can mix together. The details of the mixing is normally parametrized by the Cabibbo-Kobayashi-Maskawa (CKM) Matrix, which gives three quark mixing angles, as well as one CP-violating complex phase.
These four parameters, again, cannot be predicted from any other principle, and must simply be measured at this point in time.
22-25.) The neutrino mixing parameters. Similar to the quark sector, there are four parameters that detail how neutrinos mix with one another, given that the three types of neutrino species all have the same quantum number. As of today, the three angles have been measured with some reasonable precision, although the CP-violating phase has not been. The mixing is parametrized by (what I know as) the Maki-Nakagawa-Sakata (MNS) Matrix, although it's worth pointing out that the mixing angles are all huge compared to what they are for the quarks, so much so that the electron, muon and tau neutrinos are each superpositions of the three "fundamental" neutrino species that mix together significantly. This is because the mass differences between the different quark species is tremendous, ranging from maybe 6-to-300,000 times the mass of an electron, while the mass differences between neutrino species is at most 0.000016% an electron's mass.
26.) The cosmological constant, or the dimensionless constant driving the accelerated expansion of the Universe. This is another constant whose value cannot be derived, and is simply a measured fact, at least at this point in time.
But even this can't explain everything about the Universe! For example:
- The amount of CP-violation encoded by our constants, regardless of what the complex phase from the MNS-Matrix is, cannot explain the observed matter-antimatter asymmetry in our Universe. That requires some sort of new physics, which means there's got to be a new fundamental parameter in there, too.
- If there is CP-violation in the strong interactions, that would be a new parameter as well, and if not, the physics (or symmetry) that prevents it may well carry a new constant (or multiple constants) along with it.
- Did cosmic inflation happen, and if so, what parameter(s) is/are associated with that?
- What is the dark matter? Given the (reasonable) assumption that it's a massive particle, it almost certainly requires at least one (and probably more than one) new fundamental parameter to describe it.
And so that's where we are today.
We don't yet know where the values of these constants come from, or whether that's something that will ever be known with the information available in our Universe. Some people chalk them up to anthropics or appeal to the multiverse; I haven't given up on our Universe just yet, though!
Our journey through the cosmos continues, and there's so much more still to learn.
I don't like it, I don't like it at all. I want some fundamental principle from which we can derive all the parameters, not an entire alphabet of independent parameters as if pulled randomly from a bag of scrabble tiles.
@Rick: So do most theorists. A relatively quick search will lead you to at least four different Web sites, each of which claims to have The Theory of Everything which "predicts" "all" of these fundamental constants. I leave it to your skepticism to decide which of them is right (here's a hint: they can't all be, and N<1).
String theory wishes it could be that Fundamental Principle, but how do you choose which of the 10^500 "versions" is the right one? Other than arbitrarily, I mean...
So many clues ... one feels that the theory is hiding just out of sight, and just needs someone to ask the right question in order to explain everything!
I'm not sure I understand what's this about. Not in a sense of GUT, that's ok. Maybe I missed something, but you say:
"By time the Universe is as old as ours is — 13.8 billion years — it will look exactly the same every time in so many important ways:"
I mean.. if you punch the same numbers and operations into the calculator, you will get exactly the same result every time. That's what simulations are. I don't understand what you mean by this. If we vary those parameters even slightly, we don't get Universe like ours.
And in the end.. "Did cosmic inflation happen, and if so, what parameter(s) is/are associated with that?"
- but you basically answered this question yourself in the post Inflation, Dark Energy, and the Physics of Spacetime. So why put it here as a question?
Not trolling.. just honestly, don't understand the moral of post :)
About the relic radiation measurement….That measurement is correct and very useful, but not like a proving ground of the big bang, because such event never happen….why? Well, You can convince yourself if you are willing to read carefully: USM www.kanevuniverse.com There You can see that to explain the unity of the fields: gravitation, electrostatic and nuclear, You need to accept the endless number of spaces, tree of them is our space, subspace and over space…. What are these spaces You can see on the shown site. The examined radiation, according to USM is radiation of the subspace where is situated the so call dark matter, which is obviously not so dark. This radiation indeed is around 13 billion years old, because this is the age of the Sun, which was born on the center of our galaxy and shifting towards the periphery of the galaxy, after around 13 bln years the Sum will die. So the temperature of this dark matter in the center of our galaxy is so huge that after that amount of years the temperature decreases into several degree ( K). Because the Sun was born from this very young matter (what exactly is this matter You can see on the site shown above), shifting towards the periphery of the galaxy, there gradually is forms the basic particles from the so call proto particle, namely: proton, electron and neutrino and they gradually become heavier and the neutrino becomes lighter, the micro cosmos is thickening and macro cosmos is expand. That is why we observe from our point of view (periphery of our galaxy) the examined radiation as like only several degree (K), but if we sink into the subspace and become part from it, then this temperature will be commensurable with the temperature of the known stars in our galaxy. The different temperature places of this relic radiation, has nothing to do with discussed hypothetical big bang. Moreover in present imagination of big bang we cannot explain how this radiation exist without any mass carrier, but only like post factor of some hypothetical event – called big bang . And many more……
1. As Ethan says the fine structure constant α=e²/4πε0ħc isn’t constant, see NIST http://physics.nist.gov/cuu/Constants/alpha.html
2. Ditto for the strong coupling constant αs.
3-17 When you lift an electron against gravity you do work on it and its mass increases. It definitely isn’t constant. See https://en.wikipedia.org/wiki/Mass_in_general_relativity#Questions.2C_a… . That notwithstanding I'm confident that geometrically-derived mass ratios will be forthcoming and will gain acceptance.
18-21 no comment
22-25 no comment
26. The cosmological constant isn’t constant. See http://arxiv.org/abs/1008.3907 . The fine structure constant varies with energy, and Λ is “equivalent to an energy density in otherwise empty space”. So α varies because Λ varies. Also see http://link.springer.com/chapter/10.1007%2F3-540-40988-2_19 re α varying with gravitational potential. Since α gives the ratio of electromagnetic versus strong coupling, that means a gravitational field is a region where α and αs do not march in step.
Whilst I didn't comment on some of the above, note the general drift: fundamental constants aren't constant. Remember that next time somebody tells you about the Golidlocks anthropic universe.
I mean.. if you punch the same numbers and operations into the calculator, you will get exactly the same result every time
That is not what is meant by the phrase you quoted, SL.
It is along the lines of "No matter how you vary the letting go of the ball, it will do exactly the same thing each time". It is assuming you know that this means "it will fall down".
What Ethan is saying is that the current model will produce after 13.8 billion years a universe essentially indistinguishable from ours, looking at it at the scale of the universe.
When testing Boyle's Law, your experiment will not have the same arrangement of atoms, nor even the same number of them, but your lab experiment will have essentially the same set up as the original.
So the observed characteristics of Dark Energy as an "Energy causing expansion of spacetime", Dark Matter as "Baryonic matter that is mostly non-interacting", along with all the known forces at the strength they are and the proportions of matter in the forms proposed in the Standard Model, produce a universe at ~14 billion years old that is the same size, matter composition, acceleration, range of stellar prototypes, clumping of visible matter and all the universe-level phenomena indistinguishable from the one we currently see.
The only things that need putting in to the simulation (therefore not a consequence of the interactions simulated) are the values like the fine structure constant, masses of the proton, et al.
These do not fall out of some other theory.
An example: Newton's Law of Motion
can be deduced from "first principles" as a result of the solution of the Shroedinger Equation if you take the values to be the average expectation rather than the discrete and singular values that classical mechanics describe.
Ergo, Newtons Law of Motion falls out as a consequence and not an axiom of the quantum nature of the universe. And with the same equation, we can do a hell of a lot more. E.g.
Explain why the electrons don't radiate and fall in to the nucleus
Explain the rates of nuclear decay
Explain the binding energies of the nucleus of atoms
What we now don't know is why that quantum nature is right.
How do I reconcile the statement "start it off with roughly the same initial conditions and these 26 fundamental constants, you’ll get roughly the same Universe each and every time" the statement that when we run the models with those constants the result is "it appears that it would look just as it appears today" and the supposition that there are other fundamental constants that we don't know - including related to cosmic inflation. Does that mean that those additional fundamental constants are irrelevant to "how the universe looks today"?
p.s. Again, please spend a few more words on your graphics. For instance, what do the various "m"s denote in the graphic associated with neutrino mixing?
bobh, read #5.
I mean.. if you punch the same numbers and operations into the calculator, you will get exactly the same result every time.
But here is the key point: The initial conditions are not exactly the same in these simulations. Each simulation is seeded with a slightly different version of background density fluctuations. As long as the initial condition is not too different from that of the actual Universe, and you use the same fundamental constants, you get a Universe that looks exactly like ours on sufficiently large scales. Ethan does leave us hanging on the question of how different things have to be before you get a significantly different universe--by how much can we tweak the various constants, or the initial fluctuation spectrum, before we get a Universe that couldn't be mistaken for the one we live in? Admittedly, that's a hard problem because there are so many dimensions to that parameter space.
Ultimately, I would think it's a statistical mechanics like argument. You could get lucky and find an initial condition that produces a substantially different Universe, but the number of possible initial conditions that do that is so much smaller than the number of possible initial conditions that produce a Universe like ours that your probability of stumbling upon such an initial condition is negligible. Likewise, all of the air molecules in this room could be in one half of the room, but there are vastly more arrangements which put half of them in the other half, so if my office mate is having trouble breathing, I should call an ambulance rather than assume that he'd be OK if he were standing next to my desk instead.
"The only things that need putting in to the simulation (therefore not a consequence of the interactions simulated) are the values like the fine structure constant, masses of the proton, et al."
-this is what I understand as well. But because of this, Ethan's sentence confused me. "and, perhaps most importantly, all of the fundamental constants will have the same value." This to me sounds opposite. It sounds like that if you put the laws of gravity, QM, etc.. and run the simulation.. you'll get the constants that we observe in nature?! If this is so.. it's magnificent, but I am under the assumption these parameters need to be input by hand. Thus the fine tuning problem of the models.
"Each simulation is seeded with a slightly different version of background density fluctuations. As long as the initial condition is not too different from that of the actual Universe, and you use the same fundamental constants, you get a Universe that looks exactly like ours on sufficiently large scales."
- yes but if you manualy put in the constants.. you wouldn't expect much change. Perhaps change in density structure, but not in the rest of things. To my understanding, and I think Ethan wrote about this also, if you change even one of them ever so slightly... you don't get our universe. Hence the invocation of anthropic principle. It's ok to have statistical chance on one value.. but on 20+ values... that is not statistical.. not unless you invoke multiverse.
"When you lift an electron against gravity you do work on it and its mass increases. It definitely isn’t constant."
The coupling to the Higgs field is constant. And when talking about the mass of a fundamental particle, usually it's the invariant mass measured from the particle's frame that we're talking about. This will also be constant. Your electron only has extra energy relative to a frame that's lower in the gravitational field.
To my understanding, and I think Ethan wrote about this also, if you change even one of them ever so slightly… you don’t get our universe. Hence the invocation of anthropic principle.
AFAIK and only going on memory, if you change any one of them alone you don't get a liveable universe (for arguments about the anthropic principle, this means capable of supporting and producing complex chemistry and existing for long periods of time). But if you start changing multiple ones simultanesouly, there are lots of universes that are livable. So the proponents of the anthropic argument are looking at a very limited sample space and concluding that only one livable universe in that sample space means design - but what they should be doing is considering the odds of a livable universe given the entire sample space.
They are doing the analogous of this: "how many ways can I roll a 7 on two dice...IF I hold this one die to be a six. Only one way? Out of 36 possible rolls, that isn't very many!" You can't argue that way about probablity.
Aack, html fail. The first paragraph in @13 is Sinisa's, the second two are mine.
“and, perhaps most importantly, all of the fundamental constants will have the same value.” This to me sounds opposite.
If the constants are not constant but inevitable, then they will come back every time with a "GUT" that is an accurate description of everything, exactly the same values (or maybe with some very tiny wiggle room).
If it were that Ethan was saying that running the SM now gives the same constants for proton mass, et al, then he wouldn't have had to say "perhaps".
If we can get a model of the standard model written down without having to pre-suppose the mass of a quark, and that simulating this universe *always* gave the same resulting values, then this would indicate that the model was able to predict precisely what those values are.
This doesn't mean we know WHY those had to be the emergent property of the model any more than "produces a diagonal pattern of black and white rows that repeat every 37 times" (or whatever it is) for the Langton's Ant simulation can be discovered to be a "law of nature" without just running the simulation.
Wow, "perhaps" modified "most importantly", not "all of the constants will have the same value".
Going back to wikipedia and reading this...
"At the present time, the values of the dimensionless physical constants cannot be calculated; they are determined only by physical measurement. This is one of the unsolved problems of physics."
so, again am back to square one.. I don't know what Ethan tried to say in the post :(
I don't know why it gives you a problem, because as far as I can see, the only source of problem you have is that you're quoting only small parts and haven't considered what the consequence of some of the words mean.
I genuinely don't see a problem between your quote from wiki and what Ethan has said.
“At the present time, the values of the dimensionless physical constants cannot be calculated;"
"Perhaps we can calculate them in the future.".
I'm reminded of a point in the internet's "Top 10 tips for women about men from men":
If we've said something that can be interpreted two ways and one of them is hurtful, we meant the other one.
"I don’t know why it gives you a problem"
I guess the problem was that I thought/understood Ethan saying that simulations will give the value of constants. Because of the sentence: " all of the fundamental constants will have the same value."
But if the constants are put in by hand... and it seems that way, then that sentence just doesn't make sense to me. They will have the same value because we put that value as initial condition in the simulation. This brings it back to "drop a ball and it will fall every time"..
But nevermind... :) Not that important.
No time now. But I will read this and remarks carefully. Thanks.
yes but if you manualy put in the constants.. you wouldn’t expect much change.
That's not true for every physical system out there. Take weather forecasting, for instance. A small difference in initial conditions makes the difference between whether the hurricane forming south of Cuba will, after crossing Cuba, recurve out to sea without hitting the US mainland (as most such hurricanes do) or slam into the Jersey Shore (as actually happened with Hurricane Sandy--one of the forecast models predicted this track six days in advance, while the others were still predicting a recurving track). Ethan's point is that the system of equations governing how the Universe evolves isn't in this category; small changes in the initial condition produce only small changes in the final condition.
That's not exactly true, Eric. The evolution of the universe, much like the evolution of the weather, is a chaotic system -- it was in the study of gravitational systems where chaos theory was first invented.
However, just like with the weather, while you can't predict what will happen on any given day, or where exactly a galaxy will form, you can look at the overall picture and see the same patterns. There will be cold fronts and hot fronts and storms and balmy weather, in proportions that can be predicted in advance even if the specific details of where and how much cannot.
In other words your weather simulation should in every case produce what would look like an "earth-like weather system" even if the specifics vary greatly from run to run. However if you changed the rules or constants used in that simulation, then you might get something completely different with weather patterns that look like nothing on earth.
So it is with universe simulation. If you change one of the fundamental ingredients -- modify a constant here, get rid of Dark Matter there -- the result doesn't look like our universe, from the high-level perspective we're talking about here. But we don't need to know the state of the vacuum fluctuations during inflation to infinite precision to test this, like we would if we literally wanted to re-create our universe (or the weather).
Also note that just because a system is chaotic doesn't mean it jumps arbitrarily far in an arbitrarily short amount of time -- any 3-body gravitational system is chaotic, but still many orbits can be stable for billions of years and predicted that far in advance as well. You can't predict it forever, and that's the essence of chaos.
CB, re: "The coupling to the Higgs field is constant. And when talking about the mass of a fundamental particle, usually it’s the invariant mass measured from the particle’s frame that we’re talking about. This will also be constant. Your electron only has extra energy relative to a frame that’s lower in the gravitational field".
It's a horror story, CB. The raised electron's mass really does increase because you did real work on it, and conservation of energy applies. And the GR deflection of light is twice the Newtonian deflection, which applies to matter. So when you drop it and throw away the kinetic energy, the electron's mass has decreased but it looks like it's increased. Think it through: a photon doesn't actually lose energy when it goes up, or gain it going down. If it did, an infalling photon would add infinite energy to a black hole. You only measure an increased frequency because you and your clocks are running slower when you're lower. Use the unchanged photon to measure the electron mass. The only way out of it is to say the Higgs field is a "relativistic aether", then you have to say it's responsible not just for electron mass but photon momentum. But on the plus side that then means it totally squares with E=mc² and is responsible not for 1% of the mass of matter, but 100%. Mark my words, that's the way this is going to go, GR will force it. See this: http://tomwhyntie.wordpress.com/category/uncategorized/ . John Ellis and Frank Close know what they're talking about. Interesting stuff eh? Constants slipping and sliding all over the place. People are even suggesting h isn't constant, see this: http://physicsworld.com/cws/article/news/2012/mar/28/can-gps-find-varia…
The evolution of the universe, much like the evolution of the weather, is a chaotic system
And despite that, if the ocean is warm enough and the upper air divergent, the hurricanes will form and all look pretty damn familiar.
Check up on what an attractor is.
Look at the Lorentz attractor and think on this: despite it being the sine qua non of chaos, every illustration of it looks pretty much identical.
I thought eric's post was yours, and picked out a bit that was the simplest to illustrate the error with.
You'd done the same thing, CB...
Friendly fire is not very friendly
"And despite that, if the ocean is warm enough and the upper air divergent, the hurricanes will form and all look pretty damn familiar."
Yes, this is exactly the point I was making. Chaos means individual data points may diverge arbitrarily, but you still might see the same large-scale patterns even if they don't match the details.
"You’d done the same thing, CB…"
Well that was self-incriminating enough. :)
@ John Duffield
And when you accelerate a particle to 99% c, it has real work done on it and it's relativistic mass (mass as measured from some other reference frame taking into account the relative motion of the two frames) is increased by an amount equal to that kinetic energy.
However in the particle's own frame it is not moving at all and has zero kinetic energy and its mass is simply its rest mass, that energy that is due to its coupling to the Higgs. This is constant. Same thing with the gravitational potential. "Potential" here, as always, can only be measured between two points, and relative to the particle's own frame there's zero gravitational potential. Energy, like everything in relativity, is relative.
Another way to put it: If you and this particle were both in free-fall, then you would not measure any excess mass due to it having been lifted up in a gravitational field.
"Think it through: a photon doesn’t actually lose energy when it goes up, or gain it going down. If it did, an infalling photon would add infinite energy to a black hole."
The gravitational potential of a photon some distance from a finite black hole is not infinite, so why would the energy gained falling into it be infinite?
CB, when they said "Think it through", they didn't mean you think it through, you know! :-D
They want you to think it through LIKE THEY DID. No more, though less is acceptable, because then you would be in awe of their thinkology.
But if you think it through then you come to a different conclusion, and therefore show them up as a moron.
This wasn't the thinking through they were talking of...
Yes, this is exactly the point I was making. Chaos means individual data points may diverge arbitrarily, but you still might see the same large-scale patterns even if they don’t match the details.
Well that's the same point Ethan was making.
So why was it brought up to him?
CB: no problem with accelerating a particle to 0.99c. You do real work on it. Then you collide it with another particle coming the other way, and for an instant, you've got some other particle at rest wrt to you. Called a Higgs boson. It gets its rest mass from the KE you gave to the protons. Don't get hung up on frames, they're abstract things, and I say that as a relativity guy. Because energy isn't just relative, it's real. matter is made of it. Of course I don't measure the particle's extra mass in free fall. I and my instruments are made of particles too.
Re the black hole, if you drop a body into it from a very great distance, it's claimed that it ends falling at close to the speed of light. This is a fallacy, because the coordinate speed of light varies in a non-inertial reference frame, and there's a crossover point. The photon falling into the black hole doesn't gain any energy at all. None. The mass of the black hole increases by the amount of energy you drop into it. Drop a 1kg coconut into a black hole from a great distance, and even though it ends up travelling fast, the mass of the black hole increases by 1kg. Conservation of energy, CB. If there's one "law" of physics to always bear in mind, that's it. That's why the constants aren't as constant as the Goldilocks guys would have you think.
Then you collide it with another particle coming the other way, and for an instant, you’ve got some other particle at rest wrt to you.
Who said that was the case? Prove it. You're using 12th Century thinking on a quantum world. No wonder you're as confused as hell.
It gets its rest mass from the KE you gave to the protons.
No it doesn't.
Don’t get hung up on frames, they’re abstract things
So is kinetic energy. And photons. And black holes.
Because energy isn’t just relative, it’s real. matter is made of it.
Nonsensical nonEnglish drivel. Try creating some coherent sentences for a change, maybe your problem is you can't think rather than you can't write. But your inability to write indicates your basic problem.
Re the black hole, if you drop a body into it from a very great distance, it’s claimed that it ends falling at close to the speed of light
It hasn't gained infinite energy doing so. That would require it accelerate to light speed precisely.
The photon falling into the black hole doesn’t gain any energy at all.
It does gain energy. Just as anything in a potential energy well that falls deeper into that potential energy well gains energy.
Drop a 1kg coconut into a black hole from a great distance, and even though it ends up travelling fast, the mass of the black hole increases by 1kg. Conservation of energy
That isn't conservation of energy, that's conservation of mass. Where did the energy go?
TRY APPLYING conservation of energy.
I think I get the basic point: that if you start a simulation from the earliest point in the history of the universe for which we have any reasonable numbers, and run that simulation for the equivalent of 13.8 B years, the outcome on the largest scales will appear the same as what we observe today.
OK, but there are two "therefores" that I'm having trouble with:
"It will have the same number of galaxies, of the same mass, clustered together in the same ways, ..... (and).... It will have the same number of stars and planets with the same mass distribution as our Universe..."
Exactly the same number of galaxies? And exactly the same number of stars and planets?
Given that galaxies differ in mass and quantity of stars from which they are composed, how do you always end up with the same number of galaxies? Ditto for stars and planets? Seems to me the only way to get there is via some kind of superdeterminism, which IMHO isn't science because it's unfalsifiable. So the only way I can make sense of that is roughly as follows:
"It will have the same overall quantity of mass that is formed into galaxies, and the masses of individual galaxies will vary on the same scale as they do at present," and "it will have the same overall quantity of mass embodied as stars and planets; further, the masses of stars and the masses of planets will vary on the same scale as they do today."
For example you might end up in a new version of our solar system, where the mass of Earth is slightly different and its orbital distance from the Sun is slightly different, and the masses and orbits of the other planets are differently distributed, but the total mass of the solar system is the same or nearly so (averaged out with some other nearby star systems).
Is that anywhere near right? or if not, where did I screw up?
Seems to me that if any simulation using the same values for variables produces a similar universe, then any such universe will also have the same or similar conditions of chemistry and energy to give rise to life to the same degree as our actual universe.
Which gets us to the anthropic principle: to my mind it's entirely reasonable to assert that any universe we are capable of observing, will have the conditions necessary for our existence to occur. Humans and similar observers will always find themselves in universes that are inherently more hospitable to life than some other hypothetical universes.
Question is, has anyone run simulations using other values for key variables, and ended up with universes that support complex chemistry over long periods of time? In other words, of all the not-impossible ways are there to seed a universe, what percentage of those turn out to be favorable to life vs. unfavorable to life?
Exactly the same number of galaxies? And exactly the same number of stars and planets?
Depends on just how exact you want the term "exact" to be. Think of it this way: if I flip a (fair) coin 1 billion times, the result will be 50% heads and 50% tails.
It will be exactly 50/50 in the statistical sense that the deviation from 50% will be incredibly small. And the more times I flip that coin, the smaller that deviation from true 50/50 is going to get.
But if you mean by 'exactly," 'an enumeration will always lead to 500,000,000 heads - not one more or less,' the no, a billion coin flips will probably not lead to exactly 50/50.
I expect that Ethan is using 'exactly' in the statistical sense givenabove. If you have a really big universe with some truly huge amount of hydrogen (in comparison to the hydrogen in a star), and you rerun its evolution, each run is going to end up with exactly the same number of stars in the statistical sense of low deviation from the mean. And the bigger/longer the evolution of the universe you're considering, the more exact the runs are going to match. But if you were to enumerate stars, no, you would probably not arrive at the same number in each run.
TL:DR version: statistical mechanics, dude. Many independent random processes can lead to fairly exactly predictable end-states - and the more there are, the more exactly the end-state can be predicted.
"It gets its rest mass from the KE you gave to the protons. Don’t get hung up on frames, they’re abstract things, and I say that as a relativity guy."
Uh-huh. Okay Mr. Relativity Guy, what's the Kinetic Energy of an object according to an observer in a co-moving reference frame? It's zero, because the object's velocity is zero. Does it matter that you were both accelerated and given Kinetic Energy relative to some other frame? Not for any local experiment you conduct. The mass of the object will not appear greater to you in your co-moving reference frame. For it to be otherwise, as you suggest, would require that there be some "absolute" notion of velocity and thus KE. It would require that it *not* be your privilege to consider yourself to be at rest and still make sense of the universe.
You've broken the Principle of Relativity, Mr. Relativity Guy. Good going, I'm impressed.
I think Wow covered the rest of it. I do just want to specifically point out how in one sentence you claim that the gravitational potential of an object falling into a black hole is infinite -- or maybe you just don't realize that's what you're claiming when you say the object would have infinite kinetic energy when it falls in -- but then in the next completely forget that energy exists and call that "Conservation of Energy".
"Exactly the same number of galaxies? And exactly the same number of stars and planets?"
Does it matter?
Because *EXACTLY* equal isn't necessary.
What you need to do is work out if they are a different number, what consequence does that have?
And if the consequence is no discernable difference, then what the hell was the point of worrying about how the numbers weren't EXACTLY the same?
Hello. I have been following this blog off and on. I am a biologist but I find the issues of cosmology to be fascinating, and I try to incorporate some of it in my evolution class. One area of interest for me that seems relevant to this conversation thread is the 'fallacy of fine tuning'. I think I understand (and accept) the views of Victor Stenger about this. I was wondering what your thoughts were about it.
Re. Eric @ 36 and Wow @ 38:
OK, statistical probability, yeah I get that. I was looking for clarification of "...same number of..." because that wording implied exact rather than statistical.
The difference it makes, is between the statistical type of determinism that's "reasonable," and the absolutist type that's unfalsifiable and IMHO has a whiff of religiosity about it. Determinism is the nexus of a large and feisty philosophical debate in the San Francisco Bay Area and environs, and as far as I can tell, on a wider scale in the geek culture and among philosophical rationalists.
Getting back to my closing question, has anyone run simulations with different values for the key variables, that have resulted in other types of universes with the characteristics needed to support complex chemistry over long time spans? Or is it the case that we haven't even begun to scratch the surface on the ways in which the physics of any such universes would differ from our own?
This may be a digression so feel free to ignore it or make it disappear, but:
Re. the question "Why is there something instead of nothing?" (or more generally, "why does anything exist?"), this seems to be the basis for a rationally-argued kind of Deist approach to theology. Ordinarily every event has a cause, either in some obvious material sense, or due to the will of a person acting on an object. If we assert that the universe spontaneously sprang into existence, we're asserting an un-caused event.
That would leave the door open to speculation about causes, and in lieu of some theoretical physical mechanism, one might assert a basis to believe in a causal agent in the form of a deity. The conventionally religious have no need of any such reasoning, and the conventionally atheistic reject it a-priori, but it may be appealing to some as a kind of middle ground of peaceful coexistence.
Alternately, if one un-caused event is possible, why not others?
@CB re “ ...You’ve broken the Principle of Relativity, Mr. Relativity Guy..."
I haven’t broken it at all. The mass of the object doesn’t appear greater to me because I’m similarly affected. But I can look at the CMBR dipole anisotropy and work out that I have motion relative to the universe, and relative to you. And when that object hits you in the head you will be disabused of any notions that its kinetic energy is zero.
Wow didn’t cover it at all. Drop a 1kg coconut into a black hole and the mass of that black hole increases by 1kg. So when you catch a falling coconut and throw away its kinetic energy and claim its mass hasn’t reduced, you’re missing the trick.
I suggest you take a look at Compton scattering. You can convert some of the E=hf photon energy into the kinetic energy of an electron. You could do another Compton scatter with the residual photon, and another and another. Taken to the limit, you remove all energy from the wave whereupon it no longer exists. It has been totally converted into the kinetic energy of electrons. OK? Now take a look at pair production. You can convert that photon into an electron and a positron. The electron is quite literally made from kinetic energy. Energy is real, not just relative. Matter is made of it.
@CB re “ …You’ve broken the Principle of Relativity, Mr. Relativity Guy…”
I haven’t broken it at all.
Yes you did, JD, but you're too dumb to (or motivated not to) see.
CB pointed out precisely where you did just that.
Drop a 1kg coconut into a black hole and the mass of that black hole increases by 1kg.
Which you claimed was "conservation of energy".
You ignored the change in energy.
Truly one of the dumber nuts on the cluster, JD.
I was looking for clarification of “…same number of…” because that wording implied exact rather than statistical.
No, that exactitude was entirely in your interpretation. It doesn't exist.
"Tomorrow will be the same as today" aphorism doesn't mean it will be EXACTLY the same does it. But it has the same wording as Ethan's sentence.
Re. the question “Why is there something instead of nothing?” (or more generally, “why does anything exist?”), this seems to be the basis for a rationally-argued kind of Deist approach to theology
Yes. What's the problem here, though. You can use a logical argument for ANY proposition. That you can use a logical argument to propose a god and a logical argument for proposing what to eat on your night out doesn't mean anything, however.
There is no difference between a Deist god and science.
However, deists are EXTREMELY thin on the ground because such a god is not worthy of worship or discussion. The religious apologetics retreat after a claim of "The theist is just as rational!!!" apology to a deist because "God" can mean the deist one. However, to every godbotherer around, that "God" WAS NOT AND NEVER WAS a Deist one, they were a theist one. An active participant with wants and needs that revolve around the worshipper. And it is the one that the godbotherer and apologist KNOW is the non-deist one, but will refuse to let go of and will *pretend* that it wasn't merely so they can continue to claim science is a religion, just like their theist one.
Because we ALL know that if A=B and B=C that it MUST be A=C, right? Therefore if Deist is like Science, then Science MUST be a religion! Because Deism is about god, right? and that's what a religion is, right?
Missing, of course, all the broken chains of logic in there.
has anyone run simulations with different values for the key variables, that have resulted in other types of universes with the characteristics needed to support complex chemistry over long time spans
There are an infinite number of values for each of the necessary "constants" and each are multiplicatively indipendent.
And each one is most likely to result in something that lasts less than a plank time.
Hell, we've not done the same simulation to see what the possible phase space of DNA is, and that's a HELL of a lot more computationally feasible.
And we have a much better need to do that simulation than the one you propose.
What IS done is see whether there's the POSSIBILITY of a coherent universe if we change some of those values VERY SLIGHTLY.
The answer is "Some and not by much".
Whether there are stable forms further away from this local optima is incalculable at this time.
Hell, we haven't done the stability questions PROPERLY for simulating the single bound atom that is hypers-stable beyond lead (eka-lead). We've got it down to "it's probably right about here, and should have these properties" but we haven't got even THAT accurate enough to say precisely.
And a universe like ours has 10^80 atoms...
@ John Duffield
"I haven’t broken it at all. The mass of the object doesn’t appear greater to me because I’m similarly affected."
That might make sense if you were measuring mass with a balance. However there are many ways to measure mass, such as response of a charged particle to an electric potential. Charge does not increase with velocity so the charged particle would react differently as velocity relative to the One True Reference Frame changed. E.g. we could measure the difference in different portions of earth's orbit.
This has not been seen. You're wrong. Relativity is correct.
"But I can look at the CMBR dipole anisotropy and work out that I have motion relative to the universe, and relative to you. And when that object hits you in the head you will be disabused of any notions that its kinetic energy is zero. "
If an object is moving relative to me then obviously it will have non-zero kinetic energy relative to me. If that velocity is 1m/s then the kinetic energy will be 0.5m(1m/s)^2. Not 0.5m(1/ms + velocity relative to CMB)^2. Or do you think specifying that a car accident occurred at 20km/h or 100km/h is irrelevant because the the ~500km/s velocity of the Milky Way relative to the CMB dominates, and every car collision should result in complete vaporization of both vehicles and their occupants?
The CMBR may be a convenient reference point for measuring our velocity, but that's all it is. It's no different than measuring velocity relative to Andromeda.
Claiming otherwise -- that the CMBR represents an "absolute" reference frame and quantities like velocity and KE are defined exclusively with respect to this -- is explicitly breaking the Relativity Principle.
"Drop a 1kg coconut into a black hole and the mass of that black hole increases by 1kg."
Which is wrong because you're ignoring the kinetic energy it gained from the gravitational potential -- Conservation of Energy. Or are you claiming 1kg was its mass at the point it crossed the event horizon, and it had less mass at the point where you dropped it? Because that would make sense but not make your point.
"So when you catch a falling coconut and throw away its kinetic energy and claim its mass hasn’t reduced, you’re missing the trick. "
If the coconut goes from moving to not-moving *relative to me*, then I will observe that it had a change in energy and thus mass. However this must be exactly matched by an increase in energy in the surroundings -- this may be what you miss in the black hole example. Any kinetic energy dissipated in the black hole will still add to the black hole's total energy and thus mass.
If the coconut goes from moving to not-moving *relative to something else* but the whole time I'm moving at the same velocity of the coconut, then I will notice nothing different about the coconut.
"You can convert that photon into an electron and a positron. The electron is quite literally made from kinetic energy. Energy is real, not just relative. Matter is made of it."
Energy is real, and relative. Matter is a type of energy. Specifically "matter" is considered to be particles with "rest mass", which is the energy a particle has measured from a reference frame in which the particle is motionless and *therefore has zero kinetic energy*. This is also called "invariant mass" because it's always there in any frame, the energy of the particle will never be less than that, only more due to relative velocity.
So you can make an electron *from* kinetic energy, but an electron isn't kinetic energy. It's a different kind of energy (specifically a disturbance in the electron field with a potential relative to the Higgs field, which is where its rest mass comes from).
Energy is real, and relative. You can't deny this and be a "relativity guy".
“Drop a 1kg coconut into a black hole and the mass of that black hole increases by 1kg.”
""Which is wrong because you’re ignoring the kinetic energy it gained from the gravitational potential — Conservation of Energy.""
Which is wrong because you're forgetting where the kinetic energy came from, the gravitational pull of the black hole.
In the sense that this is question of gravity, ignore the black hole, a star or the earth will have the same effect only to a smaller ( in the case of the earth) degree.
You have a coconut at rest at some distance from the massive object As it falls toward the object, it gains kinetic energy. I surmise that we all agree so far. Where does this energy come from? It comes from the gravitational attraction between the falling object and the mass. The mass ( star, black hole, planet) also gains energy in the opposite direction. The sum of the energy, that is the falling object ( coconut) and the massive object ( planet) cancel. Hense, when they collide the increase in mas off the massive object is that from the coconut, eg 1kg.
This is basic physics.
Lets consider your scenerio, where the massive object gains the energy of the coconut and the kinetic energy. This is a closed system, Without the massive object losing energy to the coconut by way of kinetic energy, we're not conserving energy, instead we're creating it. Somehow, the total energy of the system has increased ( mass of coconut plus the kinetic enegy, plus the mass of the massive object ( eg. black hole) is greater than the mass of the black hole and the coconut when they were far apart. Again this violates conservation.
"That isn’t conservation of energy, that’s conservation of mass."
E=mc^2. Mass and energy are interchangable. If you say mass is conserved you're also saying the energy is conserved. They are different ways of expressing the same idea. It's useful to separate them for most situations in our frame of reference. So it would not be wrong to say I had 4 coconuts, one is missing, but conservation of energy says that the missing one still exists, at least in some form ( the options are 1. it's still a coconut but has rolled under my couch 2. Someone ate it and not is is not a coconut anymore 3. It fell in a black hole; maybe there are other alternatives. :) We can therefore assert that the total enegery of the universe has not deminished by one conconut ) We could equally rely on conservation of mass to assert that the matter that constituted the coconut exists, even if the coconut was consumed or fell in a black hole.
"This may be a digression so feel free to ignore it or make it disappear, but:
Re. the question “Why is there something instead of nothing?” (or more generally, “why does anything exist?”), this seems to be the basis for a rationally-argued kind of Deist approach to theology. "
The question has several problems. Define "nothing".
Can you even point to nothing? If you say, deep space is empty and emptiness is "nothing". I can certainly point to the fact that space and time is curved by objects with mass. How can "nothing" be curved?
If you can't point to nothing, you really only have the example of "something". At which point you're asserting the "nothing" is possible. What do you base this on, since you have no examples?
Think about the variation of this question "Something can't come from nothing." But I can just as easily argue, "Something doesn't come from something either, that's a conservation law." Yes, you can make a pot out of clay, but the clay existed prior to the pot, you just changed it's shape, and the particles that constitute the clay existed at least 380,000 years after the big bang, and the total energy contained in those particles existed in the initial instance of the big bang, none of which you've created, but you can consider their transformation.
Ultimately we don't know what creates universes so conclusions that are made based on "something from nothing" conjecture is an argument from ingnorance.
#39 ‘fallacy of fine tuning’.
I see a few problems with the fine tuning argument ( these aren't my arguments, totally stolen from others).
1. Since we don't know where the constants of the universe came from, we can't make any conclusions about them. Doing so is an argument from ignorance.
2. Since we don't know where the constants came from, we don't know if they are variable. Maybe all universes have the same constants. Maybe they are variable but related by some equation, changing one affects the others in balance. We can speculate to see what kind of universe is created by changing a particular variable, but we can't relate that investigation to reality because we started with speculation ( something we imagined, not something we know.)
3.Given that even in our solar system the only place we've found life is in our small planet, and much of space is hostile to life with extremes of heat, cold and radiation, you can hardly characterize this as tuned for life, more so, life exists in niches.despite the hostile environment,.
In 1. above "We can make any conclusions about them" I meant to say "We can't make any conclusions about how they came about."
Just being pedantic, but...
June 1, 2013
has anyone run simulations with different values for the key variables, that have resulted in other types of universes with the characteristics needed to support complex chemistry over long time spans
There are an infinite number of values for each of the necessary “constants” and each are multiplicatively indipendent.
There are an unbounded number, probably, but not an infinite number.
"The mass ( star, black hole, planet) also gains energy in the opposite direction. The sum of the energy, that is the falling object ( coconut) and the massive object ( planet) cancel. Hense, when they collide the increase in mas off the massive object is that from the coconut, eg 1kg."
No, you're thinking of their *momentums* which are in opposite directions and cancel. Kinetic energy is a direction-less scalar and so the total energy of the system includes the SUM of the kinetic energy of coconut and black hole.
This scenario is a basic application of conservation of energy. There are three sources of energy at T=0 when coconut and black hole are stationary relative to each other:
1) black hole mass
2) coconut mass
3) gravitational potential energy between black hole and coconut.
After the black hole absorbs the coconut, the total energy must be the same: black hole original mass + coconut mass + gravitational potential energy. The latter was over the course of the experiment converted to kinetic energy, but the point is that this energy cannot just go away.
"E=mc^2. Mass and energy are interchangable. "
Exactly, which is why it should be immediately obvious that if the mass of a coconut increases as it gains kinetic energy, then the mass the black hole gains is also takes this into account. Both you and John are on the one hand acknowledging mass-energy equivalence, but then dismissing it by saying only the coconut's rest mass adds to the black hole.
This violates conservation of energy. It makes sense only if you think "conservation of mass" is a separate thing from CoE which is the point Wow was making.
I think that's what they meant anyway. I shouldn't pretend to know what they are thinking.
What you don't seem to take into consideration is that this can be looked at as a closed system. You have two masses. Mass is conserved. You have a total amount of energy. Energy is conserved. You can't have more of either, in a closed system, when you're done than when you started. In a closed system, where did the extra energy come from?
The energy didn't go away, it wasn't created or lost. Energy was exchanged between the black hole and the coconut. The kinetic energy arose from gravity. The combined gravity of the black hole and the coconut ( we'll use gravity as short hand for space/time curvature). But energy being conserved, the energy imparted to create the kinetic energy wasn't out of nowhere. It came from the blackhole and it's gravity ( and also from the coconut and it's space/time curvature, I have no prejudices against coconuts so I won't exclude its contribution). Thus the kinetic energy gained by the coconut was taken from the black hole. Repeating, the black hole lost energy, the same amount needed to accelerate the coconut. When they collide it is returned, no net gain in energy.
Both you and John are on the one hand acknowledging mass-energy equivalence, but then dismissing it by saying only the coconut’s rest mass adds to the black hole.
Not at all, the black holes mass adds to the coconut too! I'm not dismissing that at all. :)
I am saying that despite your claims, you're violating conservation of energy by including the kinetic energy of the coconut, since this is energy that was part of the closed system in the first place.
I'm not dismissing that the coconut has gained energy and by gaining energy has increased it's mass. But where did that energy come from? It' came from the black hole. The black hole lost that energy. If that coconut's trajectory was such that it missed the black hole with escape velocity, that kinetic energy was a gain for the coconut at the expense of the black hole. Measuring the mass of the black hole in this case would show that it's mass is lower by the same amount as the gain in energy of the coconut. It doesn't matter though if the coconut escapes or collides with the black hole, since the gain to one is a loss for the other, it's a wash and only the initial mass of each matters.
"You can’t have more of either, in a closed system, when you’re done than when you started. In a closed system, where did the extra energy come from?"
There is no extra energy. The gravitational potential energy -- the thing you keep ignoring -- was present as a given at the start of the experiment just like the mass of the coconut and black hole.
What this also means that in your formulation, there is LESS energy at the end, because the gravitational potential energy vanished into the aether.
Potentials across fields is a form of energy just like kinetic energy is a form of energy. You cannot properly account for Conservation of Energy and ignore this. Heck, the majority of the mass of the coconut is due to field potentials (Higgs, strong, electromagnetic) in the first place.
"But where did that energy come from? It’ came from the black hole. The black hole lost that energy."
That's just not how gravity works. Both black hole and coconut GAIN energy by accelerating towards each other. Neither loses energy in order to create gravity. However the gravitational potential between them does decrease in exact proportion to the energy gained.
Your alternate case where the coconut misses at "escape velocity" is interesting for two reasons.
One, this case is different from the collision case in that once the coconut flies past the black hole, it's kinetic energy will decrease and the gravitational potential energy between black hole and coconut will once again increase. When they collided this didn't happen, and instead the kinetic energy added to the black hole.
Two, for the coconut to reach escape velocity it must have had some initial non-zero velocity towards the black hole otherwise it could not reach a higher potential wrt the hole than what it started at. So now imagine that the coconut starts off at T=0 with significant kinetic energy. That energy will add to the black hole too. The 1kg coconut could contribute arbitrarily large amounts of mass to the black hole if we allow it to be accelerated.
Two, for the coconut to reach escape velocity it must have had some initial non-zero velocity towards the black hole
Not at all. The coconut could be at rest relative to the black hole when it starts it's fall, but the black holes motion through space over time, can make the coconut "miss" the black hole at a trajectory sufficient for escape velocity. Think in terms of a comet in the Ort cloud falling towards the sun. Some comets are ejected based on their trajectory and the motion of the sun through space.
"The coconut could be at rest relative to the black hole when it starts it’s fall, but the black holes motion through space over time"
Meaning they have some non-zero relative velocity and the coconut is not at rest relative to the black hole at the start.
"Some comets are ejected based on their trajectory and the motion of the sun through space."
Which can only happen if the comet's trajectory was affected by other objects than just the sun.
If the sun and comet were the only objects in the universe then their mutual orbit would be stable essentially forever, degrading slowly due to gravitational radiation. The comet could not be flung off at escape velocity *because that would violate conservation of energy*.
"That’s just not how gravity works. Both black hole and coconut GAIN energy by accelerating towards each other."
And that's a violation of Conservation of Energy.
The total energy of the system must be conserved on that we agree. That includes the gravity. PE + KE = Total E.
I'm not dogmatic, woof. Let me help your argument, let me know if I'm "straw maning".
Your argument is that the PE of the coconut, and that of the BH, become KE toward each other, and this KE increases the mass of each until the collision at which point the mass is greater than the two masses that we started with. ( That's not what you state in the bold above, but that's my inference.)
My contention is that the Total E of the system is the same before the collision as afterwards. Whatever happens between the two objects as they approach it irrellevent.
So it's seems that we're at an impass. Except for two issues:
1. This is why physicists do math, because you can account for all variables with math or have some smart alec point out that your equation is wrong.
2. My intent is not to be right but to explore what I know or think I know, so I'll throw a wrench in the gears of my argument.
Assume 2 coconuts, one a billion km from the BH and on a million km. Obviously they have different PE and will have different KE upon collision with the BH. Since the TE energy of the coconut/BH pair that is 1 Billion km apart is greater than that of the pair that is million km apart, conservation of E means that upon collion there will be a different effect of each.
Of course it's all talk without doing the math :)
Which can only happen if the comet’s trajectory was affected by other objects than just the sun.condition
Not at all. The comet is attracted to the position of the BH. It's accelleration is also non linear. If the BH is in motion, as it normally would be orbiting the center of the galaxy the comet will be attracted to a moving gravity well. There are at least 3 potential outcomes 1, they collide 2 they orbit and 3 the coconut is ejected.
“The coconut could be at rest relative to the black hole when it starts it’s fall, but the black holes motion through space over time”
Meaning they have some non-zero relative velocity and the coconut is not at rest relative to the black hole at the start.
No, meaning that at initial conditions the black hole and the coconut were at zero relative velocity ( that's the condition we set for this thought experiment) but since the black hole is orbiting the galaxy, as is the coconut, their relative positions change. Even though the coconut is "falling" into the BH, the BH is moving and can move in such a way to allow the coconut to be ejected from the system. Since we've only fixed the mass of the coconut ( 1 kg) and not the mass of the BH, it's radial velocity about the center of the galaxy or it's distance to the coconut, there are a set of solutions where the coconut is ejected from the black hole.
"Which is wrong because you’re forgetting where the kinetic energy came from, the gravitational pull of the black hole."
What the fuck is THAT supposed to mean?
It's so hideously wrong, it's not even not even wrong. It's incoherent and an unanswerable claim.
"In the sense that this is question of gravity, ignore the black hole, a star or the earth will have the same effect only to a smaller ( in the case of the earth) degree."
Irrelevant since this claim does NOTHING to demonstrate the validity of your previous allied claim.
"The mass ( star, black hole, planet) also gains energy in the opposite direction."
Which then doubles your problem.
“That isn’t conservation of energy, that’s conservation of mass.”
Not according to you and your other sock here it isn't. If that were true, then the gain in kinetic energy would translate into mass just like CB describes, but you and your duppel insist is not the case.
Christ, Bill, you're incoherently raving and therefore, because there is no actual cohesive message, are ensuring that you cannot be argued against, since your points are nonexistent and therefore not refutable.
Thomas Jefferson - "Ridicule is the only weapon which can be used against unintelligible propositions. Ideas must be distinct before reason can act upon them;
Something you're using deliberately I think to ensure that you cannot be gainsaid.
"There are an unbounded number, probably, but not an infinite number."
Cribbed without understanding from the definition of the universe, if closed, can be finite and unbound.
Because of your complete lack of comprehension, you have applied it where it makes no sense.
Wow - you're a ranting bore. You throwout infinity as though you could point to a physical example of it. Sure there is a concept in math called infinity that's useful, but saying that there is an inifinite number of possible input values for a given problem is incoherent.
CB- I concede the argument to you. It turns out there was somebody wrong on the internet, an in this case it happened to be me ( CRAP!) :)
Coconuts stealing energy from BH, will happen if the black hole is orbiting the galaxy by trading angular momentum ( coconut speeds up, Bh slows down.) given the proper trajectory. This was not part of the original contention and has nothing at all to do with whether the total mass of the BH + coconut is greater after they collide than before. Example rescinded.
The fact is since TE = PE + KE, given a constant mass, coconut at 1 kg, TE will differ based on varying the other mass (i.e BH) . That difference is that "extra" mass that exists when you combine the BH and the coconut, that "didn't" exist when they were far apart ( or more precisely existed as the PE between the two.)
The pair of a coconut and a small mass object has a lower TE than one and a high mass object. If their masses simply added after collision, what happened to that extra energy? Obviously that energy has to be somewhere, it is in fact that contended "extra" mass.
Bill, you incoherent nutcase.
Get the fuck away from the keyboard, you're making the universe notably dumber every time you pretend to have a thought.
(PS your pestilential presence here DESERVES a rant, you ignorant bloviating retard)
have you nothing but ad hominems? What a lack of imagination. Yet, despite you being both a bore and a boor, I do find you exceedingly amusing. I await your next volley with glee.
Your friend :)
Bill, you have given NOTHING that makes any sense. You don't even know what an ad hominem is.
It isn't insulting a moron because their claims are moronic, you imbecile, it's saying their claims are moronic because they're a moron.
Your claims are moronic.
Therefore you're a moron.
There certainly are an infinite number of possible values that the fundamental constants of the universe could take. Presumably, we could set any one of them equal to any real number. The real numbers certainly form an infinite set, in fact an infinite set with a cardinality that's greater than that of the set of natural numbers or integers.
Regarding the distinction between bounded and infinite, I might argue that the range of possible values for the constants is more likely to be infinite and bounded than it is to be finite and unbounded. Restricting a constant's value to any real number between a and b, where a and b are real numbers would yield an infinite and bounded condition on that constant. That seems more reasonable than having an unbounded, but finite range for a constant.
Thanks. Very nice summary of the constants.
I think I understand your question and it make sense. But it doesn't bother me to much.
Here's my paraphrase of your question
1) We have experiments which we interpret in terms of theories.
2) When we cross check all of those equations we find these 26 constants; which we can't solve for in the equations. You know more independent variable than we have independent equations.
3) But we can measure these 26 constants with experiment. So that is cool.
4) But now we build simulators of the universe as we knew it a long time ago; and when we run the simulator we get something that looks like our universe of today every time.
Gee, why am I not surprised? I mean my simulator had to take account of the laws of physics and these 26 measured constants. Feels like a tautology to me.
In fact if the simulator gave a different answer, then I'd conclude that either the simulator was wrong or we don't understand some physics well enough.
So Sinisa Lazarek, that is my understanding and agreement with you about this problem. If I understand you correctly; and I may not. but anyway that is my understanding. Correct me if I misunderstand the situation. But
But to me the situation is kind of like having an unabridged dictionary. And run a simulation (e.g. is like start with any word) and no matter what word you start with; by the time you daisy chain from the meaning of one word to another and reach the word "elephant" miraculously the word "elephant" means exactly the same thing or things (i.e. multiple meanings) every time. But well a dictionary is a great big system that is interconnected and goes in a circle.
So with the dictionary or the physics simulator; we followed an intrinsically tautological process. In my opinion.
So why I don't care? The universe and the particles in the universe and all of the wave functions etc know what the rules are whether we humans and our theories of physics do or not. The electron or the wave function of an electron or a whatever doesn't consult a list of formulas with 26 constants to figure out what it is suppose to do next. 26 constants is just an acknowledgement that we don't know everything. And even if we got down to 0 constants; it wouldn't mean that we finally had our theory of everything just right. Because we'd probably discover a new fundamental thing with another fundamental constant.
And besides that, if we understood the universe better with 259 constants rather than with 26 constants; we wouldn't like it but we'd call it an improvement. Because it explained something better.
And finally, I take all of these exact simulations with a grain of salt. I mean take a look at the unsolved physics problems list http://en.wikipedia.org/wiki/List_of_unsolved_problems_in_physics. As Ethan suggested, when we learn something new, e.g. dark matter, we may get a bunch of new constants.
Enough of my rambling.
Very nice summary Ethan thanks.
Gee, why am I not surprised? I mean my simulator had to take account of the laws of physics and these 26 measured constants. Feels like a tautology to me.
Except you don't get to hear the complaints about cosmology and how "We don't know nothing".
For one thing, the simulation shows we don't NEED more stuff to make a believable universe like ours. I.e. our model is COMPLETE ENOUGH to produce a universe.
You don't need to know WHY the graviational constant is the value it is to work out whether your theory that
is accurate enough to become a law.
If using that law of gravitation did NOT produce a resulting solar system that looked like ours (despite having put in the one physical constant as a given), then you know the model is wrong.
As it turns out, it was not complete, since that formula was only an approximation and breaks down when the Force involved is very high.
But as it stands, we know the standard model, including the "96% of it isn't the stuff we see" *is accurate enough*.
So those claiming that the universe isn't understood are, to the approximations of our ability to measure, wrong. And their claims are not merely "not *entirely* accurate", they're plain old "completely wrong!".
"Gee, why am I not surprised? I mean my simulator had to take account of the laws of physics and these 26 measured constants. Feels like a tautology to me.
In fact if the simulator gave a different answer, then I’d conclude that either the simulator was wrong or we don’t understand some physics well enough."
I don't know, why aren't you surprised that our understanding of the laws of physics and the constants thereof are good enough that we can simulate the 14-billion year evolution of the universe from the Big Bang to today and get something indistinguishable from the universe we actually observe?
I'm not especially surprised that the scientific method has lead us to a good understanding of the universe (though I am sometimes astonished that we can actually demonstrate this in such a way). You however seem to be unsurprised because this is a 'tautology' -- as in the result could not be anything else.
How, exactly, do you figure? This is nothing like playing musical synonyms with a dictionary where words have many imprecise meanings where you can just weasel your way in the direction you want. It's a simulation that uses our precisely defined equations and constants to determine the result.
Like you said, we could be wrong about the laws of physics, or missing a critical component, and then the result of the simulation would not match reality.
A statement that depends upon the clause "if our understanding of the universe is sufficiently correct" cannot possibly be tautological.
@ OKThen and maybe CB
"4) But now we build simulators of the universe as we knew it a long time ago; and when we run the simulator we get something that looks like our universe of today every time. "
yes and no...
My comment and still the issue I don't understand is what Ethan is trying to say. If I understood him correctly... then what he writes isn't so. So I'm still under assumption I don't understand him.
He says (sorry to quote this again):
.... it will look exactly the same every time in so many important ways:
It will have the same number of galaxies, of the same mass, clustered together in the same ways - true
The ratios of the elements in the Universe will be identical, overall, to the elemental abundance today - issue of nucleosyntesis and not large scale simulation... but ok... true
It will have the same number of stars and planets with the same mass distribution as our Universe - if no.1 is true.. this is true also. just repeated
It will have the same ratio of dark energy, dark matter, normal matter, neutrinos, and radiation as our Universe - wrong.. this is part of initial conditions of the run.. the ratios are pre-determined.. not the result of simulation
- and, perhaps most importantly, all of the fundamental constants will have the same value - this my torn :)).. all of constants are put in beforehand.. and since they are constant.. they can't change.
This last one is so important, because starting with the same rough initial conditions is what guarantees our Universe will look the way it does. - and this sentence again I don't understand. it references the constants again.
so that's what I don't understand. Sounds to me like Ethan is saying our simulations produce the values of constants that we observe. This is not so!! But I don't know how to interpret differently what he writes. Again, it's not that important. We all know what the state of current simulations are, and how they work. Just don't understand why would you write that simulations will give the results of constants being what they are, when it's not the case.
. it will look exactly the same every time in so many important ways:
Therefore not identical. Otherwise "in so many important ways" would not be necessary.
so that’s what I don’t understand. Sounds to me like Ethan is saying our simulations produce the values of constants that we observe. This is not so!!
Indeed it isn't so. for either of those claims.
It's neither calculated out of first principles and neither is Ethan saying they are.
the issue is not with the sentence you quoted but with this.." all of the fundamental constants will have the same value"
He made the choice to go for parallel structure in each of his bullet points in the list that phrase appeared in, at what was perhaps the expense of clarity. There's nothing more to it than that. Don't get too hung up on parsing.
"There’s nothing more to it than that. Don’t get too hung up "
i thought as much.. but OKthen picked it up.. so I replied. Won't touch it again.
"Except you don’t get to hear the complaints about cosmology and how “We don’t know nothing”."
I do read this blog so I hear the complaints.
And I do read many research reports on arXiv, so I hear the discussion.
And I try to be part of the discussion, here and elsewhere.
And I agree in context with Ethan's next post "most scientific theories are wrong."
And science to date does have a very good understanding about how the universe works.
But I personally expect 100 or 1000 or more years of excellent science that will topple much of what we think is certain today. That's just my personal opinion.
For a more reasoned opinion, mai I recommend the book A Different Universe by Robert B. Laughlin. One of his concluding remarks, pg 213, is "a larger portion of the accepted knowledge base of modern science is untrue than was the case in the Age of Reductionism, obligating us to look at it more skeptically than we did before and to value consensus less."
About fundamental constants he has this to say, pg 18, "One of the reasons physicists so rarely talk about the collective nature of measurements of fundamental constants is that it has such deeply troubling implications... But the electron charge is another matter. We are accustomed to thinking of this charge as a building block of nature requiring no collective context to make sense. The experiments in question, of course, refute this idea. They reveal that the electron charge makes sense only in a collective context.".. etc.
"I do read this blog so I hear the complaints."
OK, so you ignore them because they're being levied at someone else's job.
"And science to date does have a very good understanding about how the universe works."
Or is it that you think that your opinion isn't that, therefore it isn't worth considering?
Because that statement there is either pointless or in contradiction to the one I quoted earlier. Just because YOU don't stridently claim "SCIENCE HAS IT ALL WRONG!!! SKY DRAGONS!!!!" doesn't mean that there is universal accord.
I think I can sum up your "response" there, OKThen, with this:
"I don't need to be shown that, therefore it shouldn't have been done".
I guess after all this time; you just don't know me very well.
Hmm, is there anyone that you do not fight?
People who don't say stupid shit in public.
Hmm, is there something wrong with not putting up with crap?
We put up with your crap, and there is a lot of it; because we've gotten to know and appreciate your insights, explanations, perspective, and your willingness to stand blow for blow with the anti-science folks.
I've gotten to know yo out here; and I do think of you as an internet friend. And that means that I give you space, courtesy, the benefit of the doubt. Try it.
I once had a disagreement with a locksmith. I had unintentionally insulted him. He ordered me out of his shop. I just wanted a key made. I paused and looked at him and said something like, "You know the world is a pretty messed up place. And if you and I can't figure out how to talk civilly; there is no hope for this world. I apologize, I didn't mean to insult you. Can we start over?" He said, "Yes."
I think I told you that I am one of the angriest people that I know. Still am after more than well a long time. But I try my best to keep my problems out of relationships. Even casual day to day encounters with key makers, cashiers, people I will never see again. Maybe especially, people I will never meet.
Like out here on the internet. I mean, I do know how to rip someone a new asshole. I just seldom can justify it. And mostly I apologize to people if I've unintentionally hurt someone. I try to give people a break because I know I say stupid thing, my wife does, my mother did,... in fact everyone that I care about and respect says stupid things.
OKThen, you don't "put up with my crap" any more than I or anyone else puts up with yours.
But you're butthurt here because the appropriation of someone else's harm so you can silence people who don't do things the way you want them to be done.
Cry me a fucking river.
"Oh, someone else may be upset by calling them cranks!".
Well why must YOU be the one complaining for them? If they aren't being upset enough to come here and say themselves, then they can't be THAT upset by it, can they.
No, this is passive-aggressive shit trying to shame people into doing what YOU want them to do.
Sorry, buddy, try the farm, they're buying that shit over there.
As to your words on why this simulation was made, your biggest gripe seems to be that YOU don't see the need for it, and nobody gives a flying fig because, sorry to say, the world does NOT revolve around your lugholes, no matter what relativity says.
"because the appropriation of someone else's harm... is being denied." my mind changed sentences half way through.
This is an example. Yes I know what each word means; and yes I know this quote is a legal phrase. But truthfully I have no idea what the quote phrase means even after an interesting Google search. But specifically I have no idea what YOU mean.
Sorry, what the HELL are you on about now???
You're trying a passive-aggressive stunt and are now going off on any wild tangent to pretend that you've not been caught with your knickers round your ankles.
You are hilarious.
I still have no idea what you are talking about.
No stunt. No wild tangent.
You do make me laugh.
Where you find your humour is your business. Why tell me about it?
For a long discussion of the facts relating to the anthropic principle and cosmic fine tuning of fundamental constants, with many links to scientific papers and quotes
from scientists, see my recent blog post
Cosmic Fine-Tuning Visualized