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Physicists Debate Hawking’s Idea That the Universe Had No Beginning

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Re: Physicists Debate Hawking’s Idea That the Universe Had No Beginning

#231

Post by lliamander »

mythrwy wrote: post #211
lliamander wrote: post #138

Earlier quoted context omitted.

A valid question, and not one that in my opinion (even though I am a theist) that has an argument that is both clear and compelling (look up various Ontological arguments to see the gamut). I think it is enough to say the following things: 1. The universe clearly exists, but it is also clear that it doesn't have to exist (i.e. the universe is contingent) 2. Therefore, there must be some thing that exists, and exists…

Doesn't point 2 (something exists of necessity) negate point 1 (clear it doesn't have to exist)? On point 3 I fail to see logical need for external cause. Existence could simply be an intrensic property of the universe. Besides it just shuffles the "cause" issue up a level. If God can exist "just because he does and always has and is without external cause" so can a universe.

> Doesn't point 2 (something exists of necessity) negate point 1 (clear it doesn't have to exist)?

they are talking about different things. The universe is contingent, but something other than the universe (that is not contingent) is required to explain the existence of the universe.

> On point 3 I fail to see logical need for external cause. Existence could simply be an intrensic property of the universe.

Could the universe have been in a different configuration than it is? More matter, less matter, no matter, etc.? There is no contradiction in those configurations, therefore we must admit that they are possible. That means that the universe needn't be (as it is, or at all). If something could be different than the way it is, then rationally we must suppose there is an explanation for the way it is.

> Besides it just shuffles the "cause" issue up a level. If God can exist "just because he does and always has and is without external cause" so can a universe.

"God" at this point is just a placeholder to the solution of the problem of infinite regress. The universe is not a suitable stopping point for reasons stated above.

Re: Physicists Debate Hawking’s Idea That the Universe Had No Beginning

#232

Post by pdonis »

6gvONxR4sf7o wrote: post #198
pdonis wrote: post #186

Earlier quoted context omitted.

> the limit as time goes to zero There is no "time" at the "South Pole" point of the universe, or sufficiently close to it. The spacetime geometry in Hawking's model is purely spacelike in that region, not split up into "space" and "time" parts the way it is now. (As I understand the model, the boundary of the "spacelike" region" is at the beginning of inflation.) > is the south pole still a point contained on earth…

That's really cool. Thanks for the explanations :D

You're welcome!

Re: Physicists Debate Hawking’s Idea That the Universe Had No Beginning

#233

Post by Sendotsh »

om3n wrote: post #178
irrational wrote: post #62

Earlier quoted context omitted.

This kind of discussion always reminds me of the Asimov story "The Last Question" https://www.multivax.com/last_question.html

An excellently illustrated version of "The Last Question": https://imgur.com/gallery/9KWrH

I’ve never seen the animated version. That is incredibly well done. The way it takes scrolling into account is brilliant.

Re: Physicists Debate Hawking’s Idea That the Universe Had No Beginning

#234

Post by gauravjain13 »

Perhaps tangential, but: Why is science up for “debate”? We could all offer opinions around the edges of present-day human understanding, but is there any merit to these debates? Feels like a lot of fluff. I wish Feynman were still around.

Re: Physicists Debate Hawking’s Idea That the Universe Had No Beginning

#235

Post by ironmagma »

gauravjain13 wrote: post #234

Perhaps tangential, but: Why is science up for “debate”? We could all offer opinions around the edges of present-day human understanding, but is there any merit to these debates? Feels like a lot of fluff. I wish Feynman were still around.

Science is born out of debate. The only way current “science” came to be is through postulating and testing of those postulates, the testing of which reveals many flaws in theories and then those theories are tossed out. The fact that the truths we see now seem fixed is merely an illusion of the present. In fifty years, 20% of the current theories could seem like garbage compared to what we will have in the future.

Re: Physicists Debate Hawking’s Idea That the Universe Had No Beginning

#236

Post by thatoneuser »

gauravjain13 wrote: post #234

Perhaps tangential, but: Why is science up for “debate”? We could all offer opinions around the edges of present-day human understanding, but is there any merit to these debates? Feels like a lot of fluff. I wish Feynman were still around.

I think that's the most interesting part of science - the place where brilliant minds hypothesize and ponder about what may be. Sure it's fluff but we'd no doubt say similar of Einstein prior to his publications in the early 1900s if we were there then.

We live in a world of echo chambers. Where people can't imagine thoughts other than what they've been fed. I think that while this isn't rigorous, it's a healthy thing in moderation.

Re: Physicists Debate Hawking’s Idea That the Universe Had No Beginning

#237

Post by [deleted] »

thatoneuser wrote: post #236
gauravjain13 wrote: post #234

Perhaps tangential, but: Why is science up for “debate”? We could all offer opinions around the edges of present-day human understanding, but is there any merit to these debates? Feels like a lot of fluff. I wish Feynman were still around.

I think that's the most interesting part of science - the place where brilliant minds hypothesize and ponder about what may be. Sure it's fluff but we'd no doubt say similar of Einstein prior to his publications in the early 1900s if we were there then. We live in a world of echo chambers. Where people can't imagine thoughts other than what they've been fed. I think that while this isn't rigorous, it's a healthy thin…

[deleted]

Re: Physicists Debate Hawking’s Idea That the Universe Had No Beginning

#238

Post by kregasaurusrex »

Balgair wrote: post #54
djsumdog wrote: post #10

This seems different than the concept of infinite time, where prior to the big band there was something the collapsed into a ball of energy and maybe someday our universe will collapse back again (which has lost merit since we've seen matter in the universe isn't slowing down in spreading apart, but accelerating .. meaning in a few trillion years, atoms may be so far apart that light can't reach anything .. the event…

Wikipedia's 'Timeline of the Far Future' is a great article on the posibilities of our universe's fate [0]. Of note are the entries near the end of the list. Year 10^(10^(50)) : Estimated time for a Boltzmann brain to appear in the vacuum via a spontaneous entropy decrease [1] Year 10^(10^(120)) : High estimate for the time for the universe to reach its final energy state, even in the presence of a false vacuum. Year…

If I had to choose a favorite article on all of Wikipedia, this would be it. Almost reads like a sci-fi novel of our own personal voyage through the cosmos.

Re: Physicists Debate Hawking’s Idea That the Universe Had No Beginning

#239

Post by crazygringo »

RcouF1uZ4gsC wrote: post #142
dmbaggett wrote: post #108

Earlier quoted context omitted.

You might be interested in Our Mathematical Universe by Max Tegmark. He tries to argue that, fundamentally, the universe is "just math." In other words (glossing over enormous complexity here) if the basic axioms of math are true, the universe must exist. I have to admit I didn't fully buy the line of reasoning. But it's very interesting.

> if the basic axioms of math are true Isn't the problem that you can't prove axioms. We intuitively "know" them to be true but without proof.

You can't use deduction to prove them... but you use induction to show them to be statistically non-violated through experience so far.

Re: Physicists Debate Hawking’s Idea That the Universe Had No Beginning

#240

Post by senectus1 »

naringas wrote: post #154
EMM_386 wrote: post #118

Pure nothingness has no potential for creation. The laws of physics don't invent themselves, so it would seem that true "nothing" never existed. I'm not talking about the quantum soup of the vacuum of space, because that is something. If we take Hawking's idea that the universe smoothed out to a zero point where there was no time and nothing else, how does that point because laws of physics, gravity, etc? What proper…

> Pure nothingness has no potential for creation. I disagree, pure nothingness has the largest potential for creation because by virtue of not being there (nor anywhere) it doesn't prevent anything at all from creating itself. if this sounds strange is because the concept of nothingness is strange. rather than asking why is there nothing rather than something, I marvel at how we can conceptualize 'nothingness' in suc…

the more i think about this the more wrong i think you are.

You're assuming that "nothingness" isn't an impediment to creation of something... it may very well be the ultimate barrier to something being created.

We'll probably never know, but at the end of the day until we can devise a way to define and measure "nothingness" we cant setup any experiments (thought or otherwise) to develop theories from/about it.

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