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This question already has an answer here:

This is all based on some thoughts this article gave me.

Assertions

  • The big bang theory is currently accepted theory about the origin of the universe
  • Infinitely dense implies some kind of material (I avoid the term matter intentionally) - think of it as the fabric the universe is made of (irrelevant what it is at its core)

Question

If the point was indeed infinitely dense it would suggest that it never runs out of whatever that material is that defines its density, right?

From that viewpoint it would seem to be logical that the universe will keep expanding and expanding as the ("spatial") origin never runs out of the material the universe is made of, right?

So doesn't the big bang theory as it stands imply the ever-expanding universe outcome?

I wonder, because there is still no consensus about it in the scientific community, it seems.

Remarks

Now I am aware that the physics of the beginning of the universe is theoretical and oftentimes beyond comprehension, in short: mind-boggling. This is why I came up with that question.

I'm just wondering whether one cannot automatically deduce one (ever-expanding universe) from the other (infinitely dense point at origin of universe)?

Or is my fallacy the one that the infinitely dense point refers not to the fact that the amount of material $x$ at that point is $\infty$, but rather because the space of a point is $0$? So because of that it doesn't matter whether $x = \infty$ at all? ...

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marked as duplicate by Jon Custer, Buzz, ZeroTheHero, stafusa, sammy gerbil Dec 28 '18 at 12:36

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • $\begingroup$ I can't claim to know enough about cosmology to give you anything close to a definite answer, but I was going to point out what you write in your last paragraph: Just because a density $n=\frac{x}{y}$ approaches infinity in some limit, you cannot conclude that $x$ approaches infinity in that limit. So your initial assumption is flawed. $\endgroup$ – RQM Feb 12 '15 at 15:11
  • $\begingroup$ @RQM: yeah well, that's the thing with stuff like $\infty$ I guess. It sounds like an absolute value, when it's not. And yet, infinitely dense suggests there is no end to the density. $\endgroup$ – 0xC0000022L Feb 12 '15 at 17:58
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    $\begingroup$ Possible duplicate of Did the Big Bang happen at a point? $\endgroup$ – John Rennie Dec 21 '18 at 7:00
  • $\begingroup$ @JohnRennie how is this a duplicate when the alleged duplicate asks about the very assertion I am taking as a given (cause) and when I ask for the consequence following from the that assertion (effect)? And it's already all in my question so why would I need/want to edit it. But this question is old, so I don't really care. While the answers there are useful, I don't see how this is a duplicate. But at least three people agree with your assertion, so what I can I do ... $\endgroup$ – 0xC0000022L Dec 22 '18 at 9:59
  • $\begingroup$ The universe didn't start as an infinitely dense point so your question is founded on an assumption that isn't true. $\endgroup$ – John Rennie Dec 22 '18 at 10:06
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The term "infinite" when used in this context simply means incalculable. It is not suggested that the origin "point" was actually "infinitely" dense, merely that there is currently no way to mathematically theorize with any accuracy exactly how dense all the energy and matter of the universe would be if compressed to a single point. Infinite is much closer to a reasonably accurate description than "really very dense" and plus; it sounds way cooler.

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