Absolute 0 at the before the begging

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Discussion Overview

The discussion revolves around the conditions of the universe before the Big Bang (BB), particularly focusing on the existence of absolute zero and the nature of energy at that time. Participants explore theoretical frameworks and the implications of quantum theories of spacetime in relation to these concepts.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants question whether absolute zero existed before the universe began expanding, suggesting that if everything was condensed into one area, there may have been no energy.
  • Others argue that the events occurring shortly after the BB are difficult to determine, with some suggesting that theories about the pre-BB state are not robust enough to be considered strong.
  • A participant mentions the need for a quantum theory of spacetime to clarify what existed at time zero, referencing loop quantum cosmology as a potential framework that suggests there may not have been a singularity at that time.
  • Another participant posits that while there may have been energy in the sense of mass-energy equivalence, thermal energy likely did not exist due to the absence of particles in the early universe.
  • Concerns are raised about the limits of energy and curvature in the context of loop quantum gravity, questioning how these factors might influence the minimum volume of the universe at its inception.

Areas of Agreement / Disagreement

Participants express a general consensus that the conditions before the BB are not well understood, with multiple competing views on the existence of absolute zero and the nature of energy at that time. The discussion remains unresolved with no clear consensus on these points.

Contextual Notes

Participants acknowledge limitations in current theories and the speculative nature of discussions regarding the pre-BB state, emphasizing that many aspects remain unproven and contingent on ongoing research in quantum cosmology.

The Grimmus
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Before the Univers started it's exspanding everything was supposedly condensed into 1 area did absolute zero exist, was there no energy?
 
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Mmmm, Frankly - even being someone who recognizes the power of science. I think most would agree that the events that occurred roughly 1/4 of a second after the BB or less are impossible to determin. After 1/4 things developed into what we think of them as, our materials etc...

...but before 1.4 it is very much flimsy. There are theories but even I would not consider them strong enough to last.

For instance, before the BB there may have been nothing at an point. This universe was not even here.
 
Waiting for a quantum theory of spacetime to answer what was there at t=0.
 
Originally posted by Eh
Waiting for a quantum theory of spacetime to answer what was there at t=0.

Loop quantum cosmology as developed by Bojowald is such
a theory and extends continuously back to zero and before.
Bojowald is just a postdoc working for Ashtekar at Penn State.
So the most impressive statements about this are coming from Ashtekar, giving overviews based on work by Bojowald in collaboration with other people. the results are recent and, while not conclusive, very suggestive that there probably was no singularity at time zero.

Bojowald "Absence of Singularity in Loop Quantum Cosmology" arxiv:gr-qc/0102069 (this is just 4 pages)

Bojowald/Morales-Tecotl "Cosmological applications of loop quantum gravity" arxiv:gr-qc/0306008 (this a recent 2003 paper with references to online papers by Bojowald and co-authors, however this one is 42 pages)

Bojowald "Homogeneous Loop Quantum Cosmology" arxiv:gr-qc/0303073 (this has computer-generated pictures on page 16 of a wave packet moving right through the classical time-zero singularity, however the paper is over 20 pages and quite technical)

for a non-technical overview:
Ashtekar "Quantum Geometry in Action: Big Bang and Black Holes"
arxiv:math-ph/0202008

these are all on line, to turn the arxiv code into a link type, for example,

http://www.arxiv.org/math-ph/0202008

that gives the abstract, with a button to download the PDF

Current work in the quantum theory of spacetime is exploratory and suggestive rather than conclusive. LQG only succeeds as a model of space and the 4D version of it----Spin Foams----was only recently invented. So what you say: "waiting for a quantum spacetime model" is exactly right. I would like to see a spinfoam model calculated for timezero. But in the meantime Bojowalds ad hoc treatment is shedding some light on the subject.
 
Last edited by a moderator:
Originally posted by The Grimmus
Before the Univers started it's exspanding everything was supposedly condensed into 1 area did absolute zero exist, was there no energy?

i agree with crystal studios that it is impossible to discover what happened in the very beginning, but as for your question of energy i would say that yes,it would be abolute zero temp.. because heat is the movement of particles and in the early beginging there were no particles. there might have been energy in the e=mc2 sence, but as for thermal energy, probably not.
 
Originally posted by CrystalStudios
Mmmm, Frankly - even being someone who recognizes the power of science. I think most would agree that the events that occurred roughly 1/4 of a second after the BB or less are impossible to determin. After 1/4 things developed into what we think of them as, our materials etc...

...but before 1.4 it is very much flimsy. There are theories but even I would not consider them strong enough to last.

For instance, before the BB there may have been nothing at an point. This universe was not even here.

Its not quite as large as a 1/4 of a second, there are pretty much set in stone theories about what the universe was like after
1x10^(-30)s.
 
Marcus, do you know if the total energy (not net) of the early universe would contribute to it's size in LQG? In other words, there is a limit to how small an arbitrary volume of the universe you can find, and this should limit the big bang initial size as wel. But if there is also a limit on the amount of curvature any given volume can have, wouldn't an increase in energy neccessarily increase the minimum volume as well?
 

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