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  #31 (permalink)  
Old 02-April-2008, 03:59 PM
JimJast JimJast is offline
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Originally Posted by CodeSlinger View Post
Since you have failed to answer my questions, here they are again, in clarified form:

1. Please show us, mathematically, why energy cannot be conserved in an expanding universe.

2. Please show us, mathematically, why conservation of energy necessarily implies a stationary universe.
First of all, your first quoted above statement isn't true since I answered your questions and if you don't understand something in the answers then you should ask about it rather than to repeat the questions. Then I might try to explain it to you in a simpler language that won't look to you like an "impressive word salad".

I don't know you since BAUT displays on my comp with a lot of errors and doesn't allow to see the profile of the person whom I'm responding to (neither allows to set a profile). I was able to figure out that you are not a physicists if you have to look to wikepedia for definition of Poynting vector. Had I have known this I wouldn't use Poynting vector as an example but I'd try to use some other vector that is also conserved and which you might understand better. Like e.g. (pseudo)vector of angular momentum (I hope you know this one). Since the principle works for either of them the same way in curved spacetime. This way you might start understanding what it is all about and why your ideas about conservation of energy in curved spacetime are ATM ideas.

Of course you need to understand what curved spacetime is, but if you want to discuss Einstein's universe coming to this thread you have to understand at least what we are talking about here.

Quote:
Poynting's Theorem, which is where the Poynting vector appears, says nothing of the sort. The theorem establishes conservation of energy for EM fields. It has nothing to do with curved spacetime.
This doesn't sound promissing since apparently you aren't aware of the fact that we all live in a curved spacetime (otherwise there wouldn't be any gravitation where we live) and so the physics to be accurate has to work in a curved spacetime without even mentioning it. That's why what you said above makes no sense to a physicists. Since you didn't know that, it was easy to guess that you are not a physicists. Which is of course OK since everybody should understand the world including non physicists.

Second, your questions aren't about "Einstein's universe" that I hoped to discuss in this thread but they are your private ATM questions on a different subject (and so your action is called here "highjacking the thread" and is a bannable offense).

Third, I'm not interested very much in discussing your ATM ideas on curved manifolds and Noether theorem, that you don't understand. What I answered is a plain mainstream response and if you don't accept the mainstream you should open your own ATM thread dedicated to those questions and put there your point of vew on conservation of energy. I might come there and explain to you why you should rather stick to the mainstream point of view.

I said in my first message that I hope to bring into the discussion "people who are supporting the mainstream view (others don't need to apply)" and I'd like to keep it this way. Your ATM ideas, though interesting, I can handle when you open a thread about them. I might come there and explain all your doubts in detail. Just make your own thread and don't highjack mine.

Fourth, wikipedia does not represent the mainstream view. By design it expresses the opinion of majority (decided by editors through concensus) in hope that it turns out to be the mainstream opinion. In most cases it is unless about things that people have strong opinions about. An example may be wikipedia's article on gravitation where the authors, almost a century after Einstein's gravitation theory has been discovered, are still talking about the "attractive force", since this is what the majority still believe in (they think that Einstein didn't explain gravitational force just made it more accurate -- whatever it means). Of course it is not the mainstream opinion. The mainstream uses Einsteins gravitation since always. If you want to follow wikipedia blindly then you are bound at some point to get into conflict with the mainstream (like those "gravitation" authors).

I may be a sculptor, but I have also MS in electronics, so I happen to know a lot of physics and math and since I'm involved in gravitation for over 20 years and I'm right now doing my PhD work in it I could also explain to you some interesting things if you are willing to learn. At least I can tell you what's ATM and what's the mainstream. I don't have any business in misleading you about anything and if wikipedia delivers partial knowledge don't blame me for not agreeing with wikipedia but rather learn what is the mainstream view on it from some mathematical physics or astronmy professor whom you trust.

Fifth, about your questions: let specify in sufficient detail what you didn't understand in my last response. When I know what you don't understand I may explain it to you better. Repeating the same thing twice without saying what part you don't understand makes no sense.

Quote:
3. Which physicists oppose Big Bang because of conservation of energy? So far you have only one who may or may not fit that description. Needless to say, "one" != "many".
I propose to skip this question as irrelevant. E.g. all astronomers opposed Copernicus (one guy) because of lack of paralax and yet it turned out that they were wrong and paralax was simply too small to be observed. So it turns out (and you must know that) that the truth can't be decided by concensus (and that's why wikipedia isn't a reliable source). Let's rather limit our discussion to relevant issues for this thread which is only Einstein's universe.
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Old 02-April-2008, 05:22 PM
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Quote:
Originally Posted by JimJast
First of all, your first quoted above statement isn't true since I answered your questions and if you don't understand something in the answers then you should ask about it rather than to repeat the questions.
Ah yes, the old "I'm not wrong, you just didn't understand what I said" ploy. No, there wasn't anything in your answer that I didn't understand. Your answers were just plain wrong.

Quote:
Originally Posted by JimJast
This way you might start understanding what it is all about and why your ideas about conservation of energy in curved spacetime are ATM ideas.
Are you serious? Mainstream science holds that yes, we live in curved spacetime and that energy is conserved globally. Your accusation of conservation of energy in curved spacetime as an ATM idea is plain wrong.

Quote:
Originally Posted by JimJast
Quote:
Originally Posted by CodeSlinger
Poynting's Theorem, which is where the Poynting vector appears, says nothing of the sort. The theorem establishes conservation of energy for EM fields. It has nothing to do with curved spacetime.
This doesn't sound promissing since apparently you aren't aware of the fact that we all live in a curved spacetime (otherwise there wouldn't be any gravitation where we live) and so the physics to be accurate has to work in a curved spacetime without even mentioning it.
That's precisely my point. Poynting's Theorem establishes conservation of energy for EM fields, and makes no mention of an exception in curved spacetime, which means the result is valid in curved spacetime. So your attempt to invoke the Poynting vector as proof that energy is not conserved in curved spacetime is plain wrong.

Quote:
Originally Posted by JimJast
Second, your questions aren't about "Einstein's universe" that I hoped to discuss in this thread but they are your private ATM questions on a different subject (and so your action is called here "highjacking the thread" and is a bannable offense).
My questions are about the claims you have made in support of your ATM ideas, and as such, are indeed relevant.

Quote:
Originally Posted by JimJast
Third, I'm not interested very much in discussing your ATM ideas on curved manifolds and Noether theorem, that you don't understand.
No, it is you who have shown an incorrect or ATM understanding of Noether's theorem and such.

Quote:
Originally Posted by JimJast
Fourth, wikipedia does not represent the mainstream view. By design it expresses the opinion of majority (decided by editors through concensus) in hope that it turns out to be the mainstream opinion. In most cases it is unless about things that people have strong opinions about.
Yes, I'm aware of Wikipedia's various faults. However, I believe its articles on Noether's and Poynting's theorems are accurate representations of mainstream science. I'll get to this in a second.

Quote:
Originally Posted by JimJast
Fifth, about your questions: let specify in sufficient detail what you didn't understand in my last response. When I know what you don't understand I may explain it to you better. Repeating the same thing twice without saying what part you don't understand makes no sense.

I propose to skip [the third] question as irrelevant. E.g. all astronomers opposed Copernicus (one guy) because of lack of paralax and yet it turned out that they were wrong and paralax was simply too small to be observed. So it turns out (and you must know that) that the truth can't be decided by concensus (and that's why wikipedia isn't a reliable source). Let's rather limit our discussion to relevant issues for this thread which is only Einstein's universe.
I believe the third question is quite relevant, as you made your original claim as support for your ATM idea that conservation of energy is incompatible with an expanding universe. You made the claim that "many physicists happen to doubt it because of the consevation of energy". Now the burden of proof is on you to show your evidence for this claim, or withdraw it.

Before I get to the questions, I would like to point you to the rules of the board, which includes the following:

Quote:
13. Alternative Concepts and Conspiracy Theories

If you have some idea which goes against commonly-held astronomical theory, or think UFOs are among us, then you are welcome to argue it here. Before you do, though READ THIS THREAD FIRST. This is very important. Then, if you still want to post your idea, you will do so politely, you will not call people names, and you will defend your arguments. Direct questions must be answered in a timely manner.
(bold mine)

Note that it does not say ATM proponents may pick and choose which questions to answer; all direct questions must be answered.

As I said earlier, it wasn't that I didn't understand your previous answers. They were simply wrong. So, once again, here are my direct questions for you:

1. Please show us, mathematically, why energy cannot be conserved in an expanding universe.

2. Please show us, mathematically, why conservation of energy necessarily implies a stationary universe.

3. Which physicists oppose Big Bang because of conservation of energy? So far you have only one who may or may not fit that description. Needless to say, "one" != "many".

To which I will also add:

4. If Wikipedia's description of Noether's theorem is incorrect, please cite relevant scientific sources (published papers, journal articles, textbooks, etc.) that refutes Wikipedia's description and/or confirms your description of Noether's theorem.

5. If Wikipedia's description of Poynting's theorem is incorrect, please cite relevant scientific sources (published papers, journal articles, textbooks, etc.) that refutes Wikipedia's description and/or confirms your description of Poynting's theorem.
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Last edited by CodeSlinger : 02-April-2008 at 11:02 PM. Reason: typo in the last sentence
  #33 (permalink)  
Old 02-April-2008, 07:11 PM
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Originally Posted by CodeSlinger View Post
Ah yes, the old "I'm not wrong, you just didn't understand what I said" ploy. No, there wasn't anything in your answer that I didn't understand. Your answers were just plain wrong.

Are you serious? Mainstream science holds that yes, we live in curved spacetime and that energy is conserved globally. Your accusation of conservation of energy in curved spacetime as an ATM idea is plain wrong.
Maybe you should read first Is Energy Conserved in General Relativity? by Michael Weiss and John Baez (which is a mainstream opinion).

If you still insist that the mianstream supports global conservation of energy in expanding universe then we may move ''Einstein universe" from ATM section to the mainstream section since we may utilize conservation of energy as legitimate means of deriving results. Which so far the mainstream opposed since it maintanied (e.g. prof. John Baez) that energy is not globally conserved.
  #34 (permalink)  
Old 02-April-2008, 07:40 PM
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Quote:
Originally Posted by JimJast
Maybe you should read first Is Energy Conserved in General Relativity? by Michael Weiss and John Baez (which is a mainstream opinion).
Read it. Here's my synopsis: in SR's flat spacetime, energy conservation can be formulated as either a differential equation or an integral equation, which are mathematically equivalent. When the two forms are generalized to GR's curved spacetime, the equivalence breaks down... until one introduces pseudo-tensors, which allows one to restore the equivalence.

You know what I don't see? Anything that actually supports your claim that energy is not conserved in curved spacetime. Your citation of this article to support your claim is... puzzling (I've already used "plain wrong" enough times in my previous post).

Quote:
Originally Posted by JimJast
If you still insist that the mianstream supports global conservation of energy in expanding universe then we may move ''Einstein universe" from ATM section to the mainstream section since we may utilize conservation of energy as legitimate means of deriving results.
Your insistence throughout this thread that the universe is not expanding roots this thread firmly in ATM territory.

Quote:
Originally Posted by JimJast
Which so far the mainstream opposed since it maintanied (e.g. prof. John Baez) that energy is not globally conserved.
Maybe you should read Prof. Baez's article again.

Still waiting for you to answer my direction questions to you.
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Old 03-April-2008, 01:06 AM
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Originally Posted by CodeSlinger View Post
Mainstream science holds that yes, we live in curved spacetime and that energy is conserved globally.
Thanks for addressing JimJ's assertions, which, like you, I believe are built on misconceptions, but I'm not quite studied enough to differentiate whether there are any serious assertions within what looks like word salad.

I am a little puzzled, however, at the above quote, where you agree with JimJ that "we live in curved spacetime." Locally, of course, this is true due to the gravitation of the Sun and galaxy. But cosmologically, observations point to a flat spacetime, or very nearly so. So JimJ's attempt to apply local conditions to the universe as a whole rather goes nowhere, as far as I can tell.

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Old 03-April-2008, 01:25 AM
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Quote:
Originally Posted by Cougar
I am a little puzzled, however, at the above quote, where you agree with JimJ that "we live in curved spacetime." Locally, of course, this is true due to the gravitation of the Sun and galaxy. But cosmologically, observations point to a flat spacetime, or very nearly so. So JimJ's attempt to apply local conditions to the universe as a whole rather goes nowhere, as far as I can tell.
I believe you are right, that on a cosmological scale, our universe resembles a flat spacetime. My comment was intended only to point out to JimJast that even in curved spacetime, such as found in our local vicinity, mainstream science holds energy to be conserved. I did not to mean to imply that spacetime is curved on the cosmological scale. I am not a cosmologist, nor have I played one on TV Please feel free to point out any other errors I have made!
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Old 03-April-2008, 05:46 AM
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  #37 (permalink)  
Old 03-April-2008, 02:31 PM
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I believe you are right, that on a cosmological scale, our universe resembles a flat spacetime.
I'm happy to hear you saying this since it is also my opinion. Actually my opinion is that its "total curvature" is exactly zero everywhere (unfortunately also an ATM opinion but I don't want to argue this point now, since there are more imporatant things to argue first, like e.g. the expansion of the universe, so far ATM as well).

Quote:
I am not a cosmologist, nor have I played one on TV Please feel free to point out any other errors I have made!
You havan't made any (in my ATM opinion, but since I'm exactly of your opinion we don't need to argue about it) and it gives us an adventage that you don't have the prejudices about the conservation of energy that some mathematical physicists have (e.g. all in my university). They don't even want to discuss my PhD work unless I admit that energy is not conserved globally and so the principle of conservation of energy can't be used as an argumet for "Einstein's universe" as I believe it can.

This way without any other delay we may skip arguing an irrelevant (since I'm exectly of your opinion about conservation of energy) question whether the conservation of energy is an ATM or for the mainstream issue. We have also an expansion to discuss, which is for sure an ATM issue, and also it is related to astronomy.

Since the rules are that we may only discuss questions related to astronomy and what's ATM and what's not is not an astronomy question then fromally we can't even discuss it. In any case I propose to discuss formal things like "what's what" only when we have time left for it since we have only a month for everything (for discussing my whole PhD work about "Einstein's universe"). And questions related to astronomy are more interesting anyway. Since you both are representing (at least in your mind) mainstream opinion, and luckily both agree (like me) to the conservation of energy (which I consider ATM but you don't) than it may be easier job (than with cosmologists from my U) to show you why I think that the universe is "Einstein's".

Let's start with a question why mainstream physicists don't believe that the universe is (a non expanding) "Einstein's universe".

You can present your thoughts about it. My knowledge (since I discussed it already with mathematical physicists so it is a concrete konwledge) is that mathematical physicists don't believe in conservation of energy. But since you believe that energy is globally conserved, what are your reason for such mainstream thoughts like that the universe is expanding?

My role is to show you that you can't have both thing: the expansion and conservation of energy at the same time. That's why mathematical physicists has chosen the former against the latter. They think it is better assumption. But you apparently hadn't (the same as me) so if you are cosistent in your beliefs, you have to tell me what your belief that the universe is expanding is based on.
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Old 03-April-2008, 03:54 PM
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JimJast, apparently you don't understand how this works. As the proponent of an ATM idea, it is your responsibility to address questions asked about your idea and claims you make in support of your idea. We, on the other hand, are under no obligation to answer your attempts to challenge mainstream science. If there is a mainstream concept you wish to inquire about, feel free to create threads for your questions in the Q&A section (with the caveat that you do not attempt to advocate your ATM position in the Q&A threads).

Quote:
Originally Posted by JimJast
My role is to show you that you can't have both thing: the expansion and conservation of energy at the same time.
Then show us! You can start by answering the questions I posed to you. For the third time, here are my direct questions on claims you have made in support of your ATM position:

1. Please show us, mathematically, why energy cannot be conserved in an expanding universe.

2. Please show us, mathematically, why conservation of energy necessarily implies a stationary universe.

3. Which physicists oppose Big Bang because of conservation of energy? So far you have only one who may or may not fit that description. Needless to say, "one" != "many".

4. If Wikipedia's description of Noether's theorem is incorrect, please cite relevant scientific sources (published papers, journal articles, textbooks, etc.) that refutes Wikipedia's description and/or confirms your description of Noether's theorem.

5. If Wikipedia's description of Poynting's theorem is incorrect, please cite relevant scientific sources (published papers, journal articles, textbooks, etc.) that refutes Wikipedia's description and/or confirms your description of Poynting's theorem.

Oh, and since you're throwing around remarks like this one:

Quote:
Originally Posted by JimJast
My knowledge (since I discussed it already with mathematical physicists so it is a concrete konwledge) is that mathematical physicists don't believe in conservation of energy.
I will also add:

6. Which mathematical physicists do not believe in conservation of energy?
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Old 03-April-2008, 03:56 PM
CodeSlinger
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Old 03-April-2008, 04:03 PM
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I subscribed to this thread in order to keep an eye on it. I got an email notification this morning that Chris Hillman had responded to this thread. But I don't see his post for some reason, so I'm reposting it below as it appeared in the notification I got.

---

Text deleted.

Codeslinger, Chris Hillman chose to delete his post. You should not post it here.

(If I erred and deleted your words, let me know and I can restore them.)
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Last edited by Jim : 03-April-2008 at 10:38 PM. Reason: given
  #40 (permalink)  
Old 03-April-2008, 10:47 PM
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JimJast, two items...

First, it is a violation of BAUT Rules to discuss a Moderator's action in-thread. If you have problems with a Mod's action, you should PM that Mod, another Mod, or an Administrator. There is a list in the About BAUT forum.

Second, it is a violation of BAUT Rules not to answer direct, pertinent questions about your ATM idea. From what I can tell, Codeslinger's questions are direct and pertinent; in several cases, they address issues you raised yourself. Please answer them asap.

(Keep in mind that an answer can be "I don't know" or "I can't answer now but will [when].")

I'd also strongly urge you to read the BAUT Rules for Posting and the Advice for ATM theory supporters. They might help you understand how we (try to) operate this forum.
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  #41 (permalink)  
Old 03-April-2008, 11:22 PM
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Originally Posted by Jim
Text deleted.

Codeslinger, Chris Hillman chose to delete his post. You should not post it here.

(If I erred and deleted your words, let me know and I can restore them.)
My apologies, Jim (and Chris Hillman). I thought the forum hiccuped and ate his post. Did not realize he had deleted it on purpose.
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Old 04-April-2008, 01:48 AM
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I subscribed to this thread in order to keep an eye on it. I got an email notification this morning that Chris Hillman had responded to this thread. But I don't see his post for some reason, so I'm reposting it below as it appeared in the notification I got.
It's a very fortunte thing since Chris is a guy who knows what he's talking about. I'm on the other hand a sculptor who got himself into cosmology through an accident. This accident was a result of my calculaton of the density of "Einstein's universe" (static, more properly called "stationary") that turned out to be in the middle of estimets that were 1 to 10 while my result came as 3 (in units of 10^{-27}kg/m/^3). Since my calculations were based on Hubble redshift (50 km/s/Mpc then and I just wanted to know how much of it is due to density of the universe because of gravitational friction of photons) after I got this result I started to suspect that the whole Hubble redshift is (kind of) due to dynamical friction of photons. After some discussions with mathematicians (like Chris Hillman), physicists, astronmers, and cosmologists and reading some of their books this suspicion of our universes being Einstein's deepened (to make a long, over 22 years old story, short).

---

Quote:
Originally Posted by Chris Hillman
Hi all,

I recall JimJast from many years ago when it was still somewhat safe to post in sci.physics.relativity (once a more civilized venue than it is now).
Hi Chris, I'm impressed by your memory if you still remember me. I hope you don't pretend any more that you are just a computer program (Jonh Baez gave you out).

Quote:
Originally Posted by Chris Hillman
I assume you mean "Einstein's static universe", [...] with Lambda chosen to have just the right value [...] to counterbalance the mutual gravitational attraction of the dust particles (idealized galaxies). But this model is inherently implausible (no reason is offered why Lambda would have that precise value) and it is unstable under small perturbations in the density of the dust. Not to mention that the observed cosmological redshift data are in violent disagreement with this model. These are all elementary points; see for example D'Inverno, ''Understanding Einstein's Relativity'', chapter 3.
Yes, however my understanding of Einstein's gravitation prevents me from thinking that there is such a thing in nature as "gravitational attraction". Actually, I'm puzzled why you even mentioned it since you must know that Einstein's gravitation does not allow gravitational forces acting at the distance. Gravitational forces exist only as tidal forces when particles press against each other because of their inetia (that's why they are called pseudo forces) or e.g. your butt presses the Earth when you happen to sit on the Earth.

It can be easily shown with differentiating E=mc^2 along distance (taking dE/dx and showing in about 5 minutes that it is equal -mg, just try it substituting -g/(2c) for dc/dx as it follows from Einstein's accelerating rocket or elevator, and from his equivalence principle).

Quote:
Originally Posted by Chris Hillman
It's not clear exactly what you think your professors have told you, but you appear to have badly misunderstood. As others have already noticed, it is of course -not true- that conservation of energy prevents the expansion (or contraction) of FRW models [sic].
It prevents it observationally: if energy is consered the universe is not observed to be expanding since there is no Hubble redshift left for the expansion. The whole 70km/s/Mpc is used for the dynamical friction of photons that generations of cosmologists thought it is "negligible" without ever calculating it exactly. Try to calculate it then you'll see for yourself. It should take a smart mathematician less than an hour. I did it in about eight, once I gave up all the unwarranted approximations. Now I demonstrate it to professors in a few minutes, so they rescue themselves by claiming that energy is not conserved in GR. As John Baez did in the same situation, dispite that you don't believe it. And he even tried to convince me that the kinetic enery of a falling brick comes from nowhere (when I asked him directly about it). And that's why I had to figure it out myself and now I know where it comes form. Though only one professor in my university agrees that it my explanation is strictly what Einstein's must have meant.

Quote:
Originally Posted by Chris Hillman
You seem to think that an expanding universe somehow requires the constant "creation of energy from nothing".
As I said, if you try to ignore dynamical friction of photons you need to supply energy to keep Hubble redshift to be the result of expansion. Is there any error in such a reasoning?

Quote:
Originally Posted by Chris Hillman
In fact, it seems that you are trying to express a claim which would imply that in Newtonian physics, a constant injection of energy is required for an upwardly thrown ball to keep moving upward, which is of course not true.
Of course it is not true since it would require just a one good kick, but if you want the same ball moving through the universe it is subject to dynamical friction and then it needs constant injection of energy to counter the dynamical friction. With photons it is even worse since it is not a Newtonian effect but purely relativistic. And so it is not some mysterious "tired light effect" but the effect of time runing slower at their origin similarly as reqired also by the regular gravitatinal redshift. Only that in the Hubble type redshift it turns out not quadratic with distance but exponential. And that's why it carries with itself the illusion of accelerating expansion with acceleration that is actually observd since it's theoretical value is H_o^2/2 (second term of Taylor series, first is H_o) while observed value is 0.45 H_o^2 (at least it was like that last time I looked at the data).

Quote:
Originally Posted by Chris Hillman
You must have misunderstood something you read or heard.
I might and that's why I'd like smart people in this forum to tell me what it might have been.

Quote:
Originally Posted by Chris Hillman
I like to define mathematics as the art of reliable reasoning using idealized models of simple phenomena. The fact that math is "a thought tool for not getting confused by the simple stuff" explains why physicists find it so essential. You appear not to appreciate this, which may explain why (as I see it) you are getting confused.
I appreciate this, however also I like Feynman's approach when he says: "Let me also say something that people who worry about mathematical proofs and inconsistencies seem not to know. There is no way of showing mathematically that a physical conclusion is wrong or inconsistent. All that can be shown is that the mathematical assumptions are wrong. If we find that certain mathematical assumptions lead to a logically inconsistent description of Nature, we change the assumptions, not nature."

Quote:
Originally Posted by Chris Hillman
Is it possible that you have somehow come to believe that "conservation of energy" only makes sense in Lorentzian spacetimes which possess a timelike Killing vector field? It is true that in gtr, a timelike Killing vector field is associated with a quantity which remains invariant during the motion of a test particle and which can often be interpreted as the "energy" of the test particle. It is also true that expanding or contracting FRW models lack timelike Killing vector fields. But neither of these facts imply the conclusion you apparently wish to draw! Rather, these phenomena explain why it is easier to solve the geodesic equations in manifolds which have more Killing vector fields (a larger self-isometry group).
I think that conservation of energy is true in any frame and a total energy of the particle is its Mc^2 (M being total mass, including its kinetic energy) which does not change with its position, and its so called "gravitational energy" is mc^2 (m being rest mass), that may be radated out on occasions, most likely just in photons. It isn't relevant here since it does not change anythng in the mechanism of Hubble redshift. The mechanism is the slowing of time exponentially with the distance to the source of light to compensate for the curvature of space which produces an easily derived relation that d^2T/dt/dx + 1/R = 0, where T is proper time, t coordinate time, x is distance, and R "radius of curvature of space" (all derivations are in my paper quoted at the first message).

Of course it produces Hubble constant H_o=c/R. Which happens to be observed if R=4.3 Gpc. What is not observed is about 57% of the mass of the universe required to produce average density needed for conservation of energy to work. One reason why my professors maintain that energy "is not concerved in gravitation". What do you think?

Quote:
Originally Posted by Chris Hillman
If you are really claiming that the only solutions of the Einstein field equation are "globally flat", that is incorrect. You may be confusing various notions of "flat", e.g. "conformally flat", "Ricci flat", "locally isometric to Minkowski". Last but not least, the local versus global distinction is essential in manifold theory, but from several things you have said above I think you have more elementary misconceptions to clear up first.
Might be. I think I mean "Ricci flat" but I'm not sure if it is what I mean since I never heard the term. I mean that the contraction or Ricci tensor gives zero. If you mean the same than it is "Ricci flat". I support it by hypothetizing the existence of a 3-D tensor (which I called "general time dilation tensor") that with 3-D Ricci tensor adds to zero. But not being a mathematician I might do here something silly. However it comes out from the above d^2T/dt/dx + 1/R = 0 generalized over all 3 spatial directions after multiplying it by R. I think that as for a sculptor I did anough work to make it interesting for a mathematical physicist to take it over and fix all mistakes, since I think that physics is right here. Yet Phys. Rev. Lett. editors maintain that lack of any new physics in it makes it uniteresting to their readers. So it can't be even published. And BAUT forum is the only available place where it can be kept for one month. Except of course my web page which nobody reads. So I can't even learn what are the objections against the "Einstein's universe" dispite that it sems to be physically viable proposition.

Quote:
Originally Posted by Chris Hillman
You seem to be trying to recall the definition of a "vacuum spacetime" in gtr (vanishing Einstein tensor, or equivalently, vanishing Ricci tensor). But gtr doesn't say that the gravitational field doesn't have energy, as for example an electromagnetic field has energy; it says that this energy can't be localized in the way in which we localize the energy of an electromagnetic field (see MTW section 20.4)
But notion of gravitational energy in gtr might be wrong and according to what I said above it is since if (d/dx)(mc^2)=-gm then mc^2 is the only "gravitational energy", and it is localized. And it can be also radiated out because it changes by quanta of energy (photons in this case). So I don't see problems with localizing it. Why do you say it can't be localzed?

Quote:
Originally Posted by Chris Hillman
A Ph.D. student normally wouldn't have so many serious misconceptions concerning his field of study. I'm not trying to be mean, Jim, I'm trying to save you some grief. Better to hear this now than at your oral exam, agreed?
You are not mean. You just say what you think that is right and I'm telling you why I think my way. I'm not concerned with my PhD at all. I'm just using it as a vehicle to find the truth about the universe. I've seen so many stupid things in literature, contradicting not only Einstein's theory (like e.g. existence of "gravitational attraction") but also contradicting the common sens (like lack of conservation of energy in gravitation) and revealing that the authors don't know physical facts, that I stopped beliving text books (and I have over 20 kg of them, since I trusted them once, starting with MTW that I bought first). And it is difficult to learn if you don't trust your teacher. So I can learn only through a dialog, and if you convince me that truth is different than I thought, that the universe expands, it would be great. I like to learn things that I didn't expect being true. It is the gratest thing in science. Untrue science is like a kitsch. I just suspect cosmology being a kitsch not science. And only since cosmologists (at least in my U and on the internet) say "we won't talk to you unless you give up that nonsense that energy can be conserved in gravitation". But if it is conserved then "Einstein universe" can handle quite nicely the illusion of accelerating expansion, CMBR, and presumably other things that I don't know about, so I'd like to learn which things it can't handle.
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Old 04-April-2008, 10:37 AM
JimJast JimJast is offline
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