Q: Is the universe infinitely old?

Physicist: Normally this question is only used to start fights.

Some theories posit that the big bang was the beginning of everything, and that it doesn’t make sense to talk about anything earlier, while others say that it may be impossible for the universe to have a beginning or end.  Both options are terrible.

We can track the progress of the universe all the way back to only moments after the big bang, but no further.  So we’ll never actually be able to see what happened at the instant of the big bang.  However, there are some pretty slick tools that allow us to extract results by studying the crap out of how spacetime behaves today.  Notably the Hawking Singularity Theorem.  We may be able to determine if the the big bang was a singularity (with nothing before), or just a severe “pinching” of the universe (with stuff happening before).

You can picture this as something like trying to figure out whether or not your sheets are pinned together in one place based on how they’re folded and bunched up in another place.  It’s tricky.

Bed sheets: More complicated than spacetime.

However, for all practical purposes the universe is about 15 billion years old (give or take).  If there was anything around before then, it got messed up good by the big bang.

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4 Responses to Q: Is the universe infinitely old?

  1. Brian H says:

    Or not. There are voids whose edges are receding at a rate that backtracks to periods of 70 bya or so.

  2. Claudia says:

    fractals. just as life does not begin or end. it just changes.

  3. I love this site because this is where all the mysteries of the universe are discussed.
    I already know the answer; I have known this ever since my earliest memory. The crazy thing is that YOU and everyone else KNOWS this, too.
    The question “How did Life begin?” has been discussed for billions of years, yet the answer has absolutely nothing to do with intelligence.
    Are there any humans who exist and do not know the answer? Of course there are, but they are very very rare. All of us are made of good and evil; there simply are very few people who are 100% on either side of the “good-evil” spectrum.
    And yes, it really is that simple.
    Steve Jobs last words were “OH WOW! Everything really IS SO SIMPLE!”

  4. Nainan says:

    Yes. The universe is infinitely old. It is also infinitely vast and perpetual. However, parts of the universe cyclically disintegrate and new regions develop so that on an average the universe appears unaffected. Matter is the only real entity. The very existence of matter incorporates mechanisms for these disintegrations and developments.
    Nainan

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