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Author Topic:   Does the universe have total net energy of zero?
cavediver
Member (Idle past 2583 days)
Posts: 4129
From: UK
Joined: 06-16-2005

 Message 241 of 404 (645526) 12-27-2011 4:21 PM Reply to: Message 239 by designtheorist12-27-2011 4:07 PM

Re: Not a Bad Parable - I Fixed It
 I see where you are confused. Feynman's name has come up on this thread in respect to two separate calculations. One is the net zero energy calculation. The other has to do with the energy density of empty space.

Ah, ok - sorry, yes I thought you were talking about the net zero calculation. The infinity answer to the cubic meter of empty space is simple quantum mechanics, and gives you one of the five answers that Baez presented. It is completely meaningless for this current topic. Baez's point about the zero-point energy best being considered as undetermined by quantum theory is the right way forward on that particular issue. Feynman was pointing out what a naive application of quantum mechaincs would produce.

 I have clearly stated that I am more interested in observational cosmology because observation trumps theory.

But how do you measure the effective negative gravitional energy of the Universe from observation? You cannot. It requres taking observationally determined parameters and feeding them into the theory - General Relativity in this case. Without the theory, you would still think you were living in a Newtonian universe.

 The only observational calculations presented so far show the ratio of positive to negative is not 1 but is off by three decimal places.

No, it is not. That is a recreation of the Feynman net-zero calculation, but has the mass of the Universe off by three decimal places. Once corrected, this makes the positive and negative energy contributions equal up to order of magnitude. As Feynman demonstrated.

Edited by cavediver, : No reason given.

 This message is a reply to: Message 239 by designtheorist, posted 12-27-2011 4:07 PM designtheorist has responded

 Replies to this message: Message 244 by designtheorist, posted 12-27-2011 9:34 PM cavediver has responded

NoNukes
Inactive Member

 (1)
 Message 242 of 404 (645528) 12-27-2011 4:45 PM Reply to: Message 240 by designtheorist12-27-2011 4:15 PM

Re: Discussing physics, not parables...
 I think it is time to put this thread on hiatus. We are approaching the 300 comment mark which will trigger the summation and Krauss's book is not even out yet. I would like to save some comments for discussing his evidence if he presents any.

Unless moderators deem otherwise, my intention is to address more of the bad science already posted regardless of whether you bail. I expect that you'll probably want to start a new thread to discuss the new book.

 I'm clearly asking for observational evidence to support the position of net energy of zero.

My position is that you haven't presented any evidence that the net energy is not "about" zero, where "about" means close enough to allow a quantum fluctuations origin.

You've simply argue that such is the case, which has resulted in much of the discussion being aimed at pointing out the holes in your arguments.

Edited by NoNukes, : No reason given.

 This message is a reply to: Message 240 by designtheorist, posted 12-27-2011 4:15 PM designtheorist has responded

 Replies to this message: Message 243 by designtheorist, posted 12-27-2011 9:27 PM NoNukes has responded

designtheorist
Member (Idle past 2773 days)
Posts: 390
From: Irvine, CA, United States
Joined: 09-15-2011

 Message 243 of 404 (645550) 12-27-2011 9:27 PM Reply to: Message 242 by NoNukes12-27-2011 4:45 PM

Re: Discussing physics, not parables...
 My position is that you haven't presented any evidence that the net energy is not "about" zero, where "about" means close enough to allow a quantum fluctuations origin.

The only evidence based on observation I have found so far was the Bradford table I linked above. When the ratio is off by more than three decimal places, you cannot say the net is "about" zero.

No observational evidence has been put forward by the net zero side.

 This message is a reply to: Message 242 by NoNukes, posted 12-27-2011 4:45 PM NoNukes has responded

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designtheorist
Member (Idle past 2773 days)
Posts: 390
From: Irvine, CA, United States
Joined: 09-15-2011

 Message 244 of 404 (645551) 12-27-2011 9:34 PM Reply to: Message 241 by cavediver12-27-2011 4:21 PM

Re: Not a Bad Parable - I Fixed It
 But how do you measure the effective negative gravitional energy of the Universe from observation? You cannot. It requres taking observationally determined parameters and feeding them into the theory - General Relativity in this case.

This is correct, but the pseudotensor approach does not do this. The pseudotensor approach works exactly the same way after the discovery of dark energy as it did before. That is simply not tenable to me.

 No, it is not. That is a recreation of the Feynman net-zero calculation, but has the mass of the Universe off by three decimal places. Once corrected, this makes the positive and negative energy contributions equal up to order of magnitude. As Feynman demonstrated.

I have not had a chance to read the Feynman paper yet, but you have to realize that Feynman wrote decades before the discovery of dark energy and the accelerating universe. I am interested to see Feynman's approach, but his mass of the universe may not have calculated dark matter either. There is a good chance Bradford's recreation is more reliable than the earlier work by Feynman.

Now, you can continue to discuss this but I plan to take a break for a while until the libraries open again and the book is available.

 This message is a reply to: Message 241 by cavediver, posted 12-27-2011 4:21 PM cavediver has responded

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NoNukes
Inactive Member

 Message 245 of 404 (645552) 12-27-2011 9:48 PM Reply to: Message 243 by designtheorist12-27-2011 9:27 PM

Re: Discussing physics, not parables...
 The only evidence based on observation I have found so far was the Bradford table I linked above. When the ratio is off by more than three decimal places, you cannot say the net is "about" zero.

Hasn't this question already been addressed by cavediver with effectively no response or rebuttal from you?

What "observation" is Bradford's mass for the universe based on? You claim he calculated the mass, but there is no evidence of that calculation on Bradford's website. It seems to me that Bradford simply looked up the mass of the universe.

It is simply not the case that Bradford's calculation includes observations or some modern take on cosmology that Feynman's calculation does not. In fact, the calculation methods used by the two men are roughly equivalent. In both cases, gravitational energy is estimated using by integrating the same inverse square law force law.

 This message is a reply to: Message 243 by designtheorist, posted 12-27-2011 9:27 PM designtheorist has not yet responded

Member
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 (1)
 Message 246 of 404 (645553) 12-27-2011 10:18 PM Reply to: Message 244 by designtheorist12-27-2011 9:34 PM

Re: Not a Bad Parable - I Fixed It
 This is correct, but the pseudotensor approach does not do this. The pseudotensor approach works exactly the same way after the discovery of dark energy as it did before. That is simply not tenable to me.

For reasons that you may or may not one day be able coherently to explain.

The pseudotensor calculations start with Einstein's equations. Hence they hold whatever the stress energy tensor is and so for any universe satisfying the equations. Discovering the existence of dark energy doesn't change that any more than discovering the thirteenth moon of Jupiter, they're both just one more thing in a universe which is still described by General Relativity.

Edited by Dr Adequate, : No reason given.

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NoNukes
Inactive Member

 Message 247 of 404 (645556) 12-27-2011 10:58 PM Reply to: Message 246 by Dr Adequate12-27-2011 10:18 PM

Re: Not a Bad Parable - I Fixed It
 Discovering the existence of dark energy doesn't change that any more than discovering the thirteenth moon of Jupiter, they're both just one more thing in a universe which is still described by General Relativity.

I find that this one sentence says what I've attempted to demonstrate in 25+ posts, but with 1/3 less vitriol. Awesome.

Edited by NoNukes, : change vitriol estimate from zero, to very little.

 This message is a reply to: Message 246 by Dr Adequate, posted 12-27-2011 10:18 PM Dr Adequate has not yet responded

Director
Posts: 12720
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 (1)
 Message 248 of 404 (645579) 12-28-2011 6:50 AM Reply to: Message 240 by designtheorist12-27-2011 4:15 PM

Re: Discussing physics, not parables...
I'm bumping the limit up to 400 messages. Also, when threads do reach their limit and are closed, a continuation thread is often appropriate as it can serve to refocus the discussion on the important points.

 -- Percy EvC Forum Director

 This message is a reply to: Message 240 by designtheorist, posted 12-27-2011 4:15 PM designtheorist has not yet responded

cavediver
Member (Idle past 2583 days)
Posts: 4129
From: UK
Joined: 06-16-2005

 Message 249 of 404 (645581) 12-28-2011 7:36 AM Reply to: Message 244 by designtheorist12-27-2011 9:34 PM

Re: Not a Bad Parable - I Fixed It
 This is correct, but the pseudotensor approach does not do this. The pseudotensor approach works exactly the same way after the discovery of dark energy as it did before.

Wrong, that approach works with a cosmological constant, , whatever its value. So it works with no dark enegy - - and it works with dark energy - .

 This message is a reply to: Message 244 by designtheorist, posted 12-27-2011 9:34 PM designtheorist has not yet responded

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NoNukes
Inactive Member

 Message 250 of 404 (645584) 12-28-2011 8:22 AM Reply to: Message 249 by cavediver12-28-2011 7:36 AM

Re: Not a Bad Parable - I Fixed It
And how is the proper value for the cosmological constant determined? From the supernova data that demonstrated that the expansion of the universe is accelerating.

See "The Supernova legacy survey: Measurement of omega(m), omega(lambda) and W from the first year data set". Astronomy and Astrophysics,

http://arxiv.org/PS_cache/astro-ph/pdf/0510/0510447v1.pdf

And

Improved Cosmological Constraints from New, Old, and Combined Supernova Data Sets.

http://arxiv.org/PS_cache/arxiv/pdf/0804/0804.4142v1.pdf

And

SUPERNOVA CONSTRAINTS AND SYSTEMATIC UNCERTAINTIES FROM THE FIRST THREE YEARS OF THE SUPERNOVA LEGACY SURVEY

https://tspace.library.utoronto.ca/...nley%20systematics.pdf

quote:
The Supernova Legacy Survey (SNLS) is a ﬁve year program to measure the expansion history of the universe using Type Ia supernovae (SNe Ia). The goal of this survey is to measure the time-averaged equation of state of dark energy w to 0.05 (statistical uncertainties only) in combination with other measurements and to 0.10 including systematic effects.

So perhaps we can dispense with DT's unsupported argument that there is no tie to observation with the psuedotensor approach, as well as the argument that Bradford's data does reflect observation.

Edited by NoNukes, : No reason given.

Edited by NoNukes, : No reason given.

 This message is a reply to: Message 249 by cavediver, posted 12-28-2011 7:36 AM cavediver has not yet responded

NoNukes
Inactive Member

 (1)
 Message 251 of 404 (646372) 01-04-2012 12:48 PM

State of the discussion.
Designtheorist stated three points in his OP. Since he has said that his central message has not been address, and because I don't expect DT to acknowledge that anyone other than DT has made any point whatsoever, I am going to provide my view of the discussion so far.

From the OP in message 11.

 DT writes: I understand that gravitational field energy can be negative, but the gravitational field energy between the earth and the moon is very small compared to the positive energy of the matter particles. Hawking says it less than a billionth of the positive energy. When can gravitational field energy be greater than the positive energy of the matter? If I read Hawking correctly, not until the matter is so dense it is a black hole. The entire universe would have to be a black hole for the net energy to be zero.

The basis for contrary calculations showing that the gravitational energy is about equal to the positive energy have been provided. In response, designtheorist (DT) has cited an article by Bradford in which the negative energy for various objects including the universe are calculated. DT indicates that he prefers Bradford's calculations because they are based on observation.

From Message 239

 The only observational calculations presented so far show the ratio of positive to negative is not 1 but is off by three decimal places.

Of course in reviewing Bradford's calculations we see that no reference at all is made to an observations. As has been pointed out Bradford uses a mass for the universe of 10^50 kg which is about three orders of magnitude lower than the current estimate of 8 * 10^52kg. DT claims that Bradford calculated the mass of the universe, but it has been pointed out that there is evidence of that, and that Bradford does not claim to have done so. No response from DT.

Another point, which has not been highlighted previously is that Bradford and other physicists do not dismiss the possibility that the universe is a black hole. From Bradford's article:

quote:
However, for very large and massive black holes, such as might exist at the centers of galaxies, their average density drops inversely as the square of their radius. This could mean that the Schwartzchild radius of a very massive black hole could extend well beyond the "surface" of its massive component within. In such a case, the negative equivalent mass ratio could rise from the non-uniform density profile to unity or greater, creating a net zero or negative mass that would explode.

Perhaps this is what the universe is. An ultra massive black hole, from which nothing escapes. It has masses concentrated in the centers of galaxies in quark-gluon plasmas and smaller black holes that are themselves exploding as their radii reach the critical value where their mass goes into a net negative value.

On to the second point in the OP.

 DT writes:Second, there is nothing to offset the positive heat energy of the universe. In addition to the heat output from all the stars, we have the cosmic microwave background radiation. CMB radiation is only ~2.7 kelvin, so not much above absolute zero - but when spread out over billions of light years in every direction - that's a lot of joules! Plus, there is no way to go below absolute zero. You cannot have negative thermal energy.

As was pointed out general relativity includes energy as a source of gravitational energy. DT cannot accept this and cites a crank article (Gowan's) from the internet to show that the idea is controversial.

Of course in a debate, we should not dismiss things just because they are mainstream, but I should point out that Gowan's hypothesis is that dark energy is simply the missing gravitational energy of photons. Yet DT needs dark energy to make up 70+ percent of the universe in order to make his final point.

To address DT's point more directly, Kinetic energy and thermal energy are not photonic, and thus are not excused from contributing to negative gravitational energy even if Gowan were correct. Second, negative energy simply disappearing when mass is converted to its energy equivalent in photons would violate conservation of energy. DT makes no effort to explain why we should accept this or why we should accept Gowan's theory without adopting its consequences.

 Third, the universe is expanding at an accelerating rate. Theorists are postulating some type of "antigravity force" at work called dark energy. If a gravitational field has negative energy, then dark energy must be positive energy. Since the expansion is accelerating, the antigravity energy must be greater than the gravitational energy. The WMAP Project claims to have measured the amount of dark energy.

DT believes that dark energy is unaccounted for in the current calculations that show that net energy is zero. DT dismisses calculations based on pseudo-tensors because pseudo-tensors are controversial or for other reasons. He gives short shrift to explanations that pseudo-tensors are entirely appropriate. I doubt the DT even understands the explanations.

In fact, DT's dismissal of psuedo-tensors is not rational, but personal. The use of pseudo-tensors in general relativity is not controversial, and because DT doubtless has no idea what a pseudo-tensor is, let alone how to manipulate one, his personal distaste is of no value. If it is wrong for me to dismiss hypothesis merely because they are not mainstream, surely it is just as silly to dismiss real science because of a personal incredulity.

DT was also unaware, and was peeved to find that the accelerated expansion of the universe is actually modeled by including a cosmological constant into Einstein's equations. Evidence for this proposition has been provided. This evidence alone should be enough to address the argument that GR does not reflect observational evidence. Perhaps it has.

DT wants to investigate whether Feynman's calculations of zero point energy were based on observation or pseudo-tensors. But as has already been pointed out, the search is going to be futile. Zero point energy is not the same as dark energy. Zero point energy is calculated from quantum theory rather than general relativity. We know that quantum theory predicts an enormously huge value for vacuum energy that is not consistent with the dark energy of the universe which is merely an order of magnitude or so greater than that of ordinary matter.

Edited by NoNukes, : No reason given.

Under a government which imprisons any unjustly, the true place for a just man is also in prison. The proper place to-day, the only place which Massachusetts has provided for her freer and less desponding spirits, is in her prisons, to be put out and locked out of the State by her own act, as they have already put themselves out by their principles. Thoreau: Civil Disobedience (1846)

Son Goku
Member
Posts: 1171
From: Ireland
Joined: 07-16-2005

 (1)
 Message 252 of 404 (646387) 01-04-2012 2:35 PM

Pseudotensors
Hi designtheorist,

You seem to disagree with the pseudotensor calculation of the total energy of the universe. You say this is because the pseudotensor calculation method wouldn't hold in the presence of dark energy. Can you explain why you believe this to be the case?

In other words, what is it about pseudotensors that makes them invalid in the presence of dark energy?

Tangle
Member
Posts: 8178
From: UK
Joined: 10-07-2011
Member Rating: 3.6

 Message 253 of 404 (648384) 01-15-2012 4:48 AM

Supersymmetry
My apologies if this has already been said and if I have completely misunderstood the idea, but in a programme summerising the Large Hadron Collider's activity so far, it was explained that the concept of supersymmetry has the universe as we see it being an error or a glitch - an inballance which we call the big bang.

If the universe was supersymmetrical it could not exist as we see it as everything would net to zero, it's only the fact that there is actually an inbalance that allows for existence. The implication is that there was no ultimate cause for the universe there was 'merely' a change in state of fundamental particles that have always been around - but perfectly balanced out.

(Although the concept of 'always' in meaningless before time. As is 'before time'. I'll get my coat.)

Luckily for me, according to the LHC output so far, supersymmetry is more likely to be wrong than right.

Life, don't talk to me about life - Marvin the Paranoid Android

 Replies to this message: Message 254 by NoNukes, posted 01-15-2012 7:16 PM Tangle has responded

NoNukes
Inactive Member

 Message 254 of 404 (648432) 01-15-2012 7:16 PM Reply to: Message 253 by Tangle01-15-2012 4:48 AM

Re: Supersymmetry
 If the universe was supersymmetrical it could not exist as we see it as everything would net to zero, it's only the fact that there is actually an inbalance that allows for existence.

Everything? Or is the imbalance you are describing merely between matter and anti-matter.

Under a government which imprisons any unjustly, the true place for a just man is also in prison. The proper place to-day, the only place which Massachusetts has provided for her freer and less desponding spirits, is in her prisons, to be put out and locked out of the State by her own act, as they have already put themselves out by their principles. Thoreau: Civil Disobedience (1846)

 This message is a reply to: Message 253 by Tangle, posted 01-15-2012 4:48 AM Tangle has responded

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Tangle
Member
Posts: 8178
From: UK
Joined: 10-07-2011
Member Rating: 3.6

 Message 255 of 404 (648492) 01-16-2012 4:46 AM Reply to: Message 254 by NoNukes01-15-2012 7:16 PM

Re: Supersymmetry
 Everything? Or is the imbalance you are describing merely between matter and anti-matter.

Everything. Apparently

The programme is here but it may not be accessible in the USA. (Supersymmetry is in last 10 minutes or so I think)

http://www.bbc.co.uk/...The_Hunt_for_Higgs_A_Horizon_Special

Edited by Tangle, : No reason given.

Life, don't talk to me about life - Marvin the Paranoid Android

 This message is a reply to: Message 254 by NoNukes, posted 01-15-2012 7:16 PM NoNukes has responded

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