Talk:Initial singularity

Traditional Model, First Sentence

Why is the second reference shown here? It shows neither specific descriptions of how general relativity's predictions fail nor broader criticism of the idea that the singularity was infinitely dense. Also, the first reference is simply an introduction to the Big Bounce unrelated to the criticism stated in the first sentence. This should be at least remedied by an additional sentence following the first that clarifies that the Big Bounce is an example of the mathematical model of an infinitely dense singularity being criticized (supported by the first reference). In my opinion it would be better if a more "blanket" reference of criticism was found or the first sentence removed entirely. Section 8.6 of [1] is adequate for a reference here. The Big Bounce is not prevailing criticism but rather an alternative that has been disregarded. — Preceding unsigned comment added by Nathan Vercaemert (talk) 17:58, 11 April 2024 (UTC)

[1] http://ndl.ethernet.edu.et/bitstream/123456789/34642/1/Tai%20L.%20Chow.pdf

Validity of traditional model

I'm told that the concept of a body containing all mass, energy, and spacetime in the Universe would be compressed to an infinitely dense point is dead wrong, that it's misleading pop-science and doesn't reflect the views of professional cosmologists. Thoughts on this?Docsavage20 (talk) 01:55, 19 January 2018 (UTC)

If you have a reliable source on the subject, then it may well warrant inclusion in the article. But until then, it can't be included because it's original research. 96.28.39.103 (talk) 11:27, 27 March 2018 (UTC)

Grumble. There is some patently wrong stuff here that is included with no reliable references. Why is it that getting rid of it needs reliable references? Anyhow, here are a few, starting with one of the "bibles" on this topic: "We must therefore exclude this point from the space-time manifold, as no known physical laws could be valid here." (Hawking & Ellis, Cambridge U. Press 1973, p. 137). "From a mathematical point of view, S=0 describes a spacetime singularity. If we compute the components of [the Riemann tensor] and construct invariants out of these [...], these invariants diverge as S tends to 0. It is therefore meaningless to talk of a spacetime geometry at S=0." (Narlikar, Cambridge U. Press 1993, pp. 117-118.) "Because the density rises without limit as t->0, the mass within any sphere today (even the size of our present horizon) was once packed into an arbitrarily small volume. Nevertheless, this does not justify the 'primaeval atom' terminology unless the universe is closed. The mass of an open universe is infinite: however far back we run the clock, there is infinitely more mass outside a given volume than inside it." (Peacock, Cambridge U. Press 1999, p. 86.) In light of these, and similar statements in just about every decent introductory text on physical cosmology (though usually with little or no emphasis, as the student is supposed to know already from elementary calculus that when a function is singular at some value of the independent variable, that value is excluded from its domain) I strongly recommend revising the present article to reflect the actual science, not the pop-science version (I'm willing to consider doing it, but I do not wish to find myself engaged in a silly edit war.) vttoth (talk) 21:21, 21 February 2019 (UTC)

Second paragraph in alternative theories should probably be removed. Has no / improper citations, is poorly written, may or may not be sensible (probably isn't) — Preceding unsigned comment added by 68.175.134.62 (talk) 18:29, 4 April 2020 (UTC)

Traditional model

The section titled "traditional model" doesn't actually describe what the traditional model is... Could a physicist rectify this? Furius (talk) 20:17, 30 May 2023 (UTC)