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Fri Apr 13, 2012, 06:14 AM

 

Big Bang and thermodynamics

Last edited Fri Apr 13, 2012, 07:31 AM - Edit history (1)

Here's what I don't understand about inflation cosmology.

The story goes like this, that first (or very soon after?!?!) there was was absolute heat or Planck temperature, which to my understanding means thermodynamic equilibrium where all the four basic forces were united and which is time-reversible state, if time is postulated in any form at all.

Then happens some mysterious symmetry break and irreversible thermodynamic arrow of time emerges, spatial expansion and cooling lead to emergence of more and more complexity.

But the second law and standard story says that all of this cooling and emergence of complexity leads only to entropy and heat death of thermodynamical equilibrium.

In short, process of cooling from absolute heat, where relativistic time-space and particle physics etc. is meaningless, to heat death, where relativistic time-space, particle physics etc. ceases to be meaningull. And all this complexity and variety in between. And in this state of complexity 2nd law still standing alone as axiom that cannot be mathematically derived from more fundamental principles, except circularly emerging from absolute hot and symmetry break.

Maxwell's demon to rescue? It's been killed again and again from all the known places, so where could it be hiding?

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Arrow 7 replies Author Time Post
Reply Big Bang and thermodynamics (Original post)
tama Apr 2012 OP
orpupilofnature57 Apr 2012 #1
caraher Apr 2012 #2
tama Apr 2012 #3
Jim__ Apr 2012 #4
tama Apr 2012 #6
tama Apr 2012 #7
bananas Apr 2012 #5

Response to tama (Original post)


Response to tama (Original post)

Fri Apr 13, 2012, 06:37 AM

2. Have you read Guth?

I'm not sure what you mean by "absolute heat or Planck energy."

The "founder" of inflationary cosmology, Alan Guth, wrote a very nice scientific memoir, "The Inflationary Universe," that should clarify how it works for you if you haven't previously read it. As far as I can tell, there's no special thermodynamic mystery at work here.

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Response to caraher (Reply #2)

Fri Apr 13, 2012, 07:30 AM

3. Sorry

 

I meant absolute hot and Planck temperature
http://en.wikipedia.org/wiki/Absolute_hot
http://en.wikipedia.org/wiki/Planck_temperature

String/M theory postulate that also gravity unifies with other basic fources near Planck temperature, but that leads to the "prediction" of so called landscape problem of 10 EXP 500 possible cooling and complex universes, which both stringy reductionists and critics of the theory don't find pleasing.

SUSY and the concept of spontaneous symmetry break (http://en.wikipedia.org/wiki/Symmetry_breakdown) is closely related, the question is about the thermodynamic symmetry break that causes the irreversible thermodynamical arrow of time (e.g. window can break but glass shards don't by themselves gather together as window, even though you can run the movie about window breaking backwards and make it look like they did)

Quantum mechanical processes of QFT (and Standard model) are time reversible, and the question is how does the irreversible arrow of time arise from time-reversible processes, ie. how to combine QM and thermodynamics - which is the foundation of basic notion of causality. As SUSY and String/M seem to be less and less convincing candidates for GUT or TOE, I'm wandering about the conseptual problems involved, including thermodynamics and the possible symmetry of absolute hot of Big Bang and prediction of Heat death of current inflation cosmologies. And especially the origin of thermodynamical symmetry break that creates the irreversible arrow of time in the first place.


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Response to tama (Reply #3)

Fri Apr 13, 2012, 08:29 AM

4. There is a short article by Guth about inflation online.

here

A short excerpt:

The crucial property of physical law that makes inflation possible is the existence of states of matter that have a high energy density that cannot be rapidly lowered. Such a state is called a "false vacuum," where the word "vacuum" indicates a state of lowest possible energy density, and the word "false" is used to mean temporary. For a period that can be long by the standards of the early Universe, the false vacuum acts as if the energy density cannot be lowered, since the lowering of the energy is a slow process. The underlying physics of the false vacuum state is described in the box on the left.


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Response to Jim__ (Reply #4)

Fri Apr 13, 2012, 01:17 PM

6. So

 

the suggestion by Guth is (at least practically if not exactly) zero energy ontology, gravitational field and spatial expansion of it the negative energy side which "creates" also the initial furnace of positive energy density.

Again supersymmetric physics bumps into Buddhist notion of codpenendent causality: "if this arises, that arises...".

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Response to Jim__ (Reply #4)

Fri Apr 13, 2012, 03:04 PM

7. And Victor Stenger too

 

The Universe: the ultimate free lunch
http://iopscience.iop.org/0143-0807/11/4/008

It is commonly believed that the origin of the Universe must have involved the violation of natural laws, particularly energy conservation and the second law of thermodynamics. This need not have been the case, the present author shows that the Universe could have begun from a state of zero energy and maximum entropy, and then naturally evolved into what we see today without violating any known principles of physics. The fundamental particles and the force laws they obey then come about through a series of random symmetry-breaking phase transitions during the period of exponential expansion in the first fraction of a second after the Universe appears as a quantum fluctuation.


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Response to tama (Original post)

Fri Apr 13, 2012, 09:25 AM

5. Energy isn't conserved in general relativity. nt

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