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<blockquote data-quote="freyar" data-source="post: 4629947" data-attributes="member: 40227">I mostly have to agree with Umbran; there are two main uses for the words &quot;Big Bang&quot; in modern cosmology, and neither is what they're using in the article.&nbsp; The most precise usage refers to the &quot;Big Bang singularity,&quot; the moment at which all spatial points are zero distance apart (more on this in a bit).&nbsp; Inflation would happen after this, as would everything, including the physics in the article.&nbsp; People thinking about the growth of the universe also talk about the &quot;hot Big Bang&quot; (this might be the more common usage), meaning the high-temperature soup of stuff that formed at the end of inflation (in standard modern cosmology) and leads to the formation of light nuclei, etc.&nbsp; Anything before inflation is before this &quot;Big Bang,&quot; so it's kind of silly for the article to say something before inflation is before the Big Bang in this sense.&nbsp; Furthermore, knowing 2 of the 3 scientists interviewed in the article, I don't think they would have meant this meaning for &quot;Big Bang&quot; in this context.&nbsp; I can only think they were going for a good quote.Regarding cyclic universe theories, etc: we believe that a correct theory of quantum gravity gets rid of the Big Bang singularity, so there could have been something before what would have been the Big Bang.&nbsp; That's the spirit of the cyclic models.&nbsp; But I'd emphasize that they are models and not terribly well understood or necessarily well motivated.&nbsp; Some of these do have cute names like &quot;pre-Big Bang&quot; though the main point of them is that there isn't really a Big Bang singularity.</blockquote>

[QUOTE="freyar, post: 4629947, member: 40227"] I mostly have to agree with Umbran; there are two main uses for the words "Big Bang" in modern cosmology, and neither is what they're using in the article. The most precise usage refers to the "Big Bang singularity," the moment at which all spatial points are zero distance apart (more on this in a bit). Inflation would happen after this, as would everything, including the physics in the article. People thinking about the growth of the universe also talk about the "hot Big Bang" (this might be the more common usage), meaning the high-temperature soup of stuff that formed at the end of inflation (in standard modern cosmology) and leads to the formation of light nuclei, etc. Anything before inflation is before this "Big Bang," so it's kind of silly for the article to say something before inflation is before the Big Bang in this sense. Furthermore, knowing 2 of the 3 scientists interviewed in the article, I don't think they would have meant this meaning for "Big Bang" in this context. I can only think they were going for a good quote. Regarding cyclic universe theories, etc: we believe that a correct theory of quantum gravity gets rid of the Big Bang singularity, so there could have been something before what would have been the Big Bang. That's the spirit of the cyclic models. But I'd emphasize that they are models and not terribly well understood or necessarily well motivated. Some of these do have cute names like "pre-Big Bang" though the main point of them is that there isn't really a Big Bang singularity. [/QUOTE]

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