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Author Topic:   Does the universe have total net energy of zero?
Dr Adequate
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Posts: 16107
Joined: 07-20-2006


(1)
Message 13 of 404 (643685)
12-10-2011 10:47 AM
Reply to: Message 11 by designtheorist
12-10-2011 10:19 AM


Re: Is the total net energy in the universe zero?
But Hawking speaks of the zero net energy like it is a given or a law. This is unusual.

And Percy was right to hesitate to promote your gibberish, because of course that is not what Hawking meant. So straight off we have to observe that you are drooling out pathetic gibberish about the actual meaning of the quotation that you put forward ...

... and here we go again. We are no longer talking to you about physics, instead we'll have to deal with you producing falsehoods about statements made by physicists.

And the really sad thing about this is that the actual question is interesting. But you will not let us discuss it, because you will smear your stupidity all over any genuine attempt to discuss the issue.


This message is a reply to:
 Message 11 by designtheorist, posted 12-10-2011 10:19 AM designtheorist has responded

Replies to this message:
 Message 14 by designtheorist, posted 12-10-2011 11:05 AM Dr Adequate has responded

  
Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006


(1)
Message 15 of 404 (643688)
12-10-2011 11:21 AM
Reply to: Message 14 by designtheorist
12-10-2011 11:05 AM


Re: Reply to Dr. Adequate
I was not attacking Hawking. I just did not want people to think that some kind of firmly established physical law was at work.

The law of conservation of energy tells us if the total net energy was ever zero, it should stay zero. Perhaps that is what Hawking was alluding to, but it read as something slightly different to me.

If you like, I will edit out that one throw away line. But don't complain to me if people start talking like total net energy of zero is a physical law when it isn't.

And no-one said that it was. However, you claimed that Hawking said that it was when in fact that is something that you made up in your head.

Now, having seen your method, you're not going to use this thread to discuss physics. You're going to use this thread to discuss ridiculous misinformation about statements made by physicists based on nonsensical misinterpretations of their statement which you have made up in your head. I am not looking forward to this. I would much rather we could actually discuss physics.

This is very much up to you. If you will stop uttering falsehoods, we could have a serious discussion. Otherwise, not so much.

Edited by Dr Adequate, : No reason given.


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Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006


Message 20 of 404 (643698)
12-10-2011 1:08 PM
Reply to: Message 18 by designtheorist
12-10-2011 12:35 PM


Re: Is the total net energy in the universe zero?
I completely agree that zero is an attractive number to a theoretician.

And also Joseph Silk, as quoted in your OP, says:

Gravity accounts for negative energy, whereas the mass of a star is undeniably positive. On large enough scales, once one counts all the black holes, stars, and empty space, the overall energy of the universe is close to zero (as measured). If the universe has zero energy, then it could have been spontaneously created from nothing by quantum fluctuations.

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 Message 18 by designtheorist, posted 12-10-2011 12:35 PM designtheorist has responded

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Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006


Message 35 of 404 (643736)
12-11-2011 5:06 AM
Reply to: Message 33 by Chuck77
12-11-2011 4:30 AM


Re: pseudo tensors
Ok, but there is still energy right?

But no net energy.

It's as though I gave you an IOU for a million dollars in exchange for your IOU for a million dollars. We'd then both have assets of a million dollars, which we have effectively created out of nothing, but we have no net assets, and no net wealth would have been created.

Edited by Dr Adequate, : No reason given.


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Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006


Message 77 of 404 (643798)
12-11-2011 10:16 PM
Reply to: Message 65 by designtheorist
12-11-2011 5:36 PM


Re: Does any of this matter or even make sense?
But if we can know the total energy is strongly positive - as the evidence seems to indicate ...

Please show your working.


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 Message 65 by designtheorist, posted 12-11-2011 5:36 PM designtheorist has responded

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Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006


Message 115 of 404 (643914)
12-12-2011 10:06 PM
Reply to: Message 108 by designtheorist
12-12-2011 7:19 PM


Re: Does any of this matter or even make sense?
Unsupported assertions are of no use to me. I asked for a paper which would account for dark energy and show the data and methods used to calculate zero net energy. You have not provided such a paper or even attempted to explain how the calculations could be made and include dark energy.

Try here.

Berman, Marcelo Samuel (2009). "On the Zero-energy Universe". International Journal of Theoretical Physics 48 (11): 3278

Let me know if you find any mistakes in his math.


This message is a reply to:
 Message 108 by designtheorist, posted 12-12-2011 7:19 PM designtheorist has responded

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 Message 133 by designtheorist, posted 12-17-2011 1:57 PM Dr Adequate has not yet responded

  
Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006


Message 118 of 404 (643924)
12-13-2011 1:33 AM
Reply to: Message 116 by designtheorist
12-13-2011 1:16 AM


Re: Hamiltonian definition of energy always equals net zero
It seems how one defines energy has a lot to do with the result you get from calculations. It seems Professor John Baez does not think too highly of any definition which requires energy to net to zero.

He omitted to say so in the paper, but fortunately you can read minds. That's how you found out that Stephen Hawking didn't believe in the Big Bang, wasn't it ... oh, no, you made that up.


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Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006


Message 143 of 404 (644579)
12-19-2011 9:47 AM
Reply to: Message 142 by designtheorist
12-17-2011 4:23 PM


Re: Is net zero energy universe "not even wrong?"
So if something is inevitable according to the laws of physics, we can just ignore it?

This message is a reply to:
 Message 142 by designtheorist, posted 12-17-2011 4:23 PM designtheorist has responded

Replies to this message:
 Message 144 by designtheorist, posted 12-19-2011 10:12 AM Dr Adequate has responded

  
Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006


Message 145 of 404 (644583)
12-19-2011 10:18 AM
Reply to: Message 144 by designtheorist
12-19-2011 10:12 AM


Re: Is net zero energy universe "not even wrong?"
I don't understand your question. What kinds of inevitable things are being ignored?

Apparently, the laws of physics (as known to us) make it inevitable that the net energy of the universe should be zero. And it seems that the very inevitability of the conclusion is your pretext for discounting it.


This message is a reply to:
 Message 144 by designtheorist, posted 12-19-2011 10:12 AM designtheorist has responded

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 Message 146 by designtheorist, posted 12-19-2011 12:15 PM Dr Adequate has responded

  
Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006


Message 147 of 404 (644597)
12-19-2011 12:22 PM
Reply to: Message 146 by designtheorist
12-19-2011 12:15 PM


Re: Is net zero energy universe "not even wrong?"
You seem to be displaying significant faith in the magic of science. I am going to explain some elementary aspects of the standards of science. Please forgive me if you know all of this. You probably do, but I think it is best to cover the ground anyway.

Just because someone has a PhD or wears a white coat does not mean he is right or even that what he is doing is science. Science is about open inquiry. If a scientist claims they have achieved a particular result in a published and peer-reviewed paper, the conclusion is not automatically added to our body of knowledge until the result has been replicated. If another person says "I don't believe you. Show me your data, methods and code," then the standards of science require the data, methods and code be shared so the experiment can be replicated. All the best peer-reviewed journals have policies on these matters. In fact, in the modern world, scientific data is supposed to be archived so anyone can analyze it. It is one of the basic tenets of science that scientists are supposed to be skeptical.

See http://en.wikipedia.org/wiki/Data_sharing
http://en.wikipedia.org/wiki/Scientific_data_archiving

The claim the net energy of the universe should always be zero is a theory. It is not a law. Only under certain definition of energy (hamiltonian) does the net energy level come out to zero every time. This definition was developed prior to the discovery of dark energy. So how valid is that definition of energy now?

Any theory needs to be confirmed by experiment or observation in some way. Joseph Silk (and others) have claimed the theory of zero net energy has been confirmed by observation. Silk actually claimed "measurement." I can find no evidence this is true. No one on this forum has put forward any papers which have attempted to estimate the actual positive and negative energy of the universe.

When the theory was first put forward by Feynmann in 1962/63, it is possible he attempted some estimation of positive and negative energy. I have not yet been able to find that article. But if the theory was somewhat viable in the early 1960s, the discovery of the antigravity of dark energy and the resulting accelerating universe seem to make the theory completely untenable today.

The problem seems to be that no one has thought through the issue of the accelerating universe and how it affects the theory of zero net energy.

In order for the theory of zero net energy to command any form of respect, it would need to show some confirmation by observation. And after the confirming observations were published, it would have to be replicated by others.

When you wish to say something remotely relevant to the point I was discussing, please let me know.

Edited by Dr Adequate, : No reason given.


This message is a reply to:
 Message 146 by designtheorist, posted 12-19-2011 12:15 PM designtheorist has responded

Replies to this message:
 Message 149 by designtheorist, posted 12-19-2011 12:59 PM Dr Adequate has responded

  
Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006


(1)
Message 151 of 404 (644608)
12-19-2011 1:22 PM
Reply to: Message 149 by designtheorist
12-19-2011 12:59 PM


Re: Is net zero energy universe "not even wrong?"
Everything I wrote was relevant.

No.

You used the word "inevitable" when talking about an unconfirmed theory ...

No.

... which only applies under certain definitions of energy ...

No.

... and was first theorized prior to the discovery of dark energy.

Yes. It was also theorized prior to the discovery of the thirteenth moon of Jupiter. What of it?


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Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006


(2)
Message 163 of 404 (644651)
12-19-2011 7:06 PM
Reply to: Message 161 by designtheorist
12-19-2011 6:37 PM


Re: On the nature of negative gravitational energy – Part I
Oh for fuck's sake.

Guth writes:

Thought experiment to understand the energy of gravity. Part (a) shows a hollow spherical shell of mass, and the gravitational field lines that it produces. There is a force on each piece of the shell, pulling inward. Part (b) shows how energy can be extracted as the shell is allowed to uniformly contract. Each piece of the shell is tied by a rope to an electrical generator, producing power as the piece is “lowered” toward its final position. Part (c) shows the final configuration, which includes a gravitational field in the shaded region where no field existed before. Thus, the creation of the gravitational field is associated with the release of energy.

* The mass stays the same.
* No input of energy is required, because gravity pulls every piece of the shell inwards.
* This reduces the volume enclosed by the shell.
* You are a freakin' idiot.


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 Message 161 by designtheorist, posted 12-19-2011 6:37 PM designtheorist has responded

Replies to this message:
 Message 165 by designtheorist, posted 12-19-2011 7:38 PM Dr Adequate has responded

  
Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006


Message 181 of 404 (644758)
12-20-2011 1:38 PM
Reply to: Message 165 by designtheorist
12-19-2011 7:38 PM


Re: On the nature of negative gravitational energy – Part I
How is energy extracted? What effect does the rope have when "tied" to an electrical generator?

You wrap it round the axle of the generator. The linear motion of the rope is converted into rotary motion of the axle is converted into electricity.

Isn't there an energy output in "allowing" the mass to uniformly contract?

The force of gravity converts the potential energy of the parts of the shell into kinetic energy.


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Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006


(1)
Message 193 of 404 (644832)
12-21-2011 3:53 AM
Reply to: Message 190 by designtheorist
12-20-2011 11:50 PM


Re: A Simple Thought Experiment
For one thing, it peeves me to see dark energy referred to as the Cosmological Constant. In Einstein's mind the lambda was all about maintaining a static state universe. Dark energy does not do that.

* sighs *

The cosmological constant has different effects depending on its value.

Einstein chose the value (c/√4πGρ)2 (where c is the speed of light, G is Newton's constant, and ρ is the energy density of the universe). This results in a static universe (although, as was later shown, an unstable one).

If you choose a different value for the cosmological constant you get a different universe with different properties.

The cosmological constant is not defined by what Einstein wanted it to do, but by the role it plays in the equations of GR.

When you add these facts up, it seems ridiculous to me that people are still claiming we have a net zero energy universe.

Well that was a complete non sequitur, wasn't it? Your inability to understand the cosmological constant doesn't even relate to the energy of the universe.


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Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006


Message 209 of 404 (645198)
12-24-2011 8:44 AM
Reply to: Message 208 by designtheorist
12-24-2011 7:58 AM


Re: Not a Bad Parable - I Fixed It
I'm missing the bit in your allegory which corresponds to you knowing jack shit and being wrong about everything.

This message is a reply to:
 Message 208 by designtheorist, posted 12-24-2011 7:58 AM designtheorist has not yet responded

  
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