Talk:Planck epoch
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[edit] Question about durations shorter than Planck time
Why is it meaningless to speak of durations shorter than Planck time?
Because the laws of time and space are virtually meaningless at a duration shorter than a Planck Time. Let me put it to you this way. There are fundamental constants that govern the size of particles, such as the size of electrons and protons. Also, there are laws governing our universe for large objects (General Relativity) and the universe at the small scale (quantum mechanics). These laws however have inherent contradictions of one another since they govern two aspects of the same universe, thus, there is no unifying principle that can link quantum mechanics to general relativity. The Planck time at the beginning of the universe deals with a moment in history where the laws of quantum mechanics and general relativity existed in the same realm with one another (at the Planck Length). As we have no explanation by which to unify these different principles then it is meaningless to speculate on the universe's beginning at a duration shorter than the Planck time. HuronKingofQueens
[edit] Expecting to edit here
I expect to do some writing/editing here, after adding some content to Planck scale article, and finding it's more appropriate to expand this entry instead. Current research in Planck scale dynamics is shifting from the particle physics to the astrophysics arena, with recent WMAP results and other experiments coming online. Many links also exist for Planck Era, from various educational websites. This article could now be greatly expanded, although little could be said here 3-5 years ago. I will do what I can to make this a more informative and meaningful entry, without adding too much fluff. JonathanD 04:33, 8 October 2006 (UTC)
[edit] Question about Unification of Forces at Planck Time
A question for Yevgeny: Can you cite any references which call into question the idea that the fundamental forces were unified at the Planck time? Some sources suggest that unification could have taken place later, or at a larger dimension than the Planck length, but I have found none who express doubt that the forces are unified during the Planck epoch. In fact; all I've read implies that this is the defining quality of that cosmological era. Do you have any references that state this is not true? I will cede that there may have never been a Planck era, but by definition it is that time when all the forces were unified. The question is not whether this is so, but how long it remained that way. If supersymmetry works (or is proven) it would show that the universe could grow by a factor of 1000, after the Planck time, and still remain unified before symmetry breaking forced the beginning of inflation. Please comment. JonathanD 22:33, 21 October 2006 (UTC)
- All physicists hope that it's possible to provide a unified description for all forces of nature. You would agree with me, however, that nobody has even approximately shown that such a unification actually occurs. (Of course, if it does exist, it would be reasonable for it to happen around the Planck scale, where all the interactions have a comparable strength.) Yevgeny Kats 22:53, 21 October 2006 (UTC)
[edit] Adding References Section to Article
I hope to add a references section to the article, before day's end. I would ask all editors to the Planck epoch entry to carefully note syntax. The detail of each reference is embedded in the main text for each topic section, but shows up below in the References section below.
Thanks,
JonathanD 21:06, 22 October 2006 (UTC)
[edit] When does the Planck Epoch start???
This page says that the epoch begins at 0 and ends at 10-43 seconds or 1 planck time. However http://dictionary.laborlawtalk.com/Timeline_of_the_Big_Bang says that it BEGINS at one Planck time and ends at 10-35 seconds. So im just wondering which source is true.82.2.211.133 14:18, 12 November 2006 (UTC)
[edit] "String theory has yielded meaningful insights" ?
What mathematician have you been talking to? Because last time I checked (which was just now) string theory has led to absolutely nothing, because it has no experimental basis at all. It doesn't even qualify as science, since it lacks predictive value.
Argument from mathematical elegance is ridiculous. --76.209.59.227 16:05, 3 February 2007 (UTC)
[edit] "Primodrial Neutrino detection less than useful" ?
I'm not entirely sure why the ice cube neutrino detector would be expected to provide any insight on this epoch, as all the primordial neutrinos would be expected to have energies approaching that of the microwave background radation. No known method is present for detecting such low energy neutrinos, least of all several tons of antarctic ice. In addition, its likely that neutrinos provide information only extending back to the electroweak or at most the GUT era, as the interaction energies were high enough in those epochs to be 'optically' opaque to neutrinos. Citation or links should be provided or this should be deleted.
- These notes at the IceCube web site say As a particle physics detector capable of detecting neutrinos with energies far above those produced at accelerators, IceCube will search for super-symmetric particles and the topological defects created during grand unified phase transitions in the early universe. Gandalf61 12:19, 15 March 2007 (UTC)
