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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

#221

Post by JudgeWapner »

golover721 wrote: post #184

For me the hardest idea to grasp is the concept of “nothing”. It seems to me that is something the human brain cannot possibly comprehend. There is always something as far as our senses are concerned. I guess that’s why the idea of nothingness after we die so such a hard notion to comprehend.

I can momentarily stun myself if I concentrate long enough on the idea of "what if there was just nothing? No universe, no cosmos, no light, no time, no matter. Just nothing." Think about that for a minute or two.

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

#222

Post by JudgeWapner »

SomeOldThrow wrote: post #117
ASalazarMX wrote: post #40

Earlier quoted context omitted.

It's nonsensical to wonder what happened in our universe before it existed, but if our universe has an external superuniverse, it's not illogical to wonder what happened there that caused our universe to exist.

> if our universe has an external superuniverse This is also meaningless, scientifically: there is nothing you can measure which is outside the universe. Things like a holographic universe are inherently untestable. I hope we continue looking for testable things, but this speculative path rapidly leads away from science and physics and into "linguistic tricks to confuse humans". It's not even philosophy at that point…

you can't measure emotion or moral principles but they certainly exist.

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

#223

Post by abtinf »

jerf wrote: post #103
abtinf wrote: post #17

The explanation I've found most persuasive is to take a purely philosophical approach: the universe had no beginning and will have no end because those concepts do not apply. The universe is everything. If there was something that "caused" the universe, it would just be part of the universe. If there is something after the universe ends, it would just be part of the universe. There is nothing outside the universe, if…

That's not an explanation, that's just a relabeling, moving the questions people have from the label "the universe" to the label "the observable universe", but neither answering them, nor making them any less relevant.

The universe is everything. By definition, there can be no evidence for anything outside, before, or after it. Any such evidence would be in the universe. There are no valid questions about it, nor valid answers. Any claims about something outside the universe are neither true nor false—they are completely arbitrary. They have the same intellectual status as God.

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

#224

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…

Pure nothingness cant be detected or measured because nothingness isn't there. if it was there it wouldn't be nothingness it would be something.

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

#225

Post by tuesdayrain »

philipov wrote: post #215
bobthechef wrote: post #204

Earlier quoted context omitted.

You're misunderstanding potential. Potential cannot exist of its own accord. It is secondary to something already actual and only then can it be actualized. If in the beginning there was truly nothing, and I mean also the absence of any cause that could make things exist, then there is not only nothing to actualize anything since only actual things can actualize, but not even the potential to be actualized. So no, ab…

You're speaking in tautologies. If you define "Nothingness" as "That which is unable to produce anything" and use that to conclude that it is not possible for there to be nothing at the start of the universe, you are begging the question. Your axioms trivially contain your conclusion, but why should we accept those axioms?

As a layman when it comes to physics, I've always had the impression that the nature of existence must be tautological. If the logic doesn't form a circle, then any attempt to explain the cause and effect sequence that resulted in our universe can always be met with a "well why did the first step occur"?

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

#226

Post by [deleted] »

galaxyLogic wrote: post #125
jawns wrote: post #119

Earlier quoted context omitted.

There's an interesting philosophical line of thought that distinguishes between things that are necessary and things that are contingent. A necessary thing must exist; it can't not exist. A contingent thing may exist, or it may not. In the classical definition of God, he has no beginning or end. He was not created by some other force. He exists necessarily. He just _is_. In fact, many theists describe God using terms…

Why is God a necessary thing?

[deleted]

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

#227

Post by lliamander »

bobthechef wrote: post #210
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…

> We can call this thing God, but by that we don't commit ourselves to any particular religion. At most that gets us the God of deism. Not so. The deist God is more of a Cartesian/Paleyian watchmaker, not the God of the philosophers classically understood. The God of the philosophers is very much in line with the Judeo-Christian God (not everything can be inferred through unaided reason, but much of it can). And God…

> Not so. The deist God is more of a Cartesian/Paleyian watchmaker, not the God of the philosophers classically understood. The God of the philosophers is very much in line with the Judeo-Christian God (not everything can be inferred through unaided reason, but much of it can). And God as "I am" ("ehyeh asher ehyeh") is precisely not a thing ipsum esse subsistens, or that who's essence it is to exist, and by which all things are. However, it precedes things and in doing so puts a stop to the infinite regress of having to appeal to still further things to explain the existence of things (which cannot work because we aren't trying to a chain of causes but the cause of their existence in the here and now).

I'm not sure I follow the distinction you are making. In any case, my point is that this ontological train of reasoning does not get us all the way to specific religious commitments, although we might argue that some religions are more compatible with this line of reasoning than others.

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

#228

Post by senorjazz »

rightbyte wrote: post #76
deepsun wrote: post #51

Earlier quoted context omitted.

> what, if anything, is outside the observable universe The answer is similar to the time. Remember, in cosmology there's no really separate space and time, there's only space-time. So when you're looking at the edge of the observable universe, you really looking back in time. So the answer to the question "what is outside" is the same as "what was before". Or, in simpler words, the question is meaningless, as there'…

The observable universe is a growing sphere around earth or where ever you happen to observe it. So to answer the question "what's outside" we just need to wait for the light to reach us. Obviously "outside the observable universe" must be outside of that sphere? Just because stars we see now are not still at that position doesn't make the question meaningless. The answer could be that outside the sphere, right now,…

> So to answer the question "what's outside" we just need to wait for the light to reach us.

unless what is outside is moving away faster than light (which I think it is), then it will never reach us (from my very basic layman understanding of how much space is being created as the universe expand. The reason why it can move away faster than light is that objects cannot move faster than light, but if space in the universe between two points is being created than the speed of light limit doesn't apply (for some reason I don't understand, but as people much smarter than I do understand, I will go with them)

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

#229

Post by senorjazz »

sonnyblarney wrote: post #61

I misinterpreted the direct idea of 'Big Bang' at a very young age and thought that the nature of time changed over time, ergo, 'the beginning' could never be achieved (even if you could travel backwards in time), i.e. it's 'infinitely far back' similar to how time changes for traveller/observer as one approaches the speed of light. Only in any given time frame could one mark 'the start', but that would be a misinter…

> It's fun to see smart people contemplating alternative things.

It certainly is. Most recent theory I heard of whilst staying up too late watching youtube videos, was by Roger Penrose on CCC (Conformal cyclic cosmology) [1]

My very basic understanding of it (probably wrong understanding though) was that the universe is mathmatical, thus mathmatical tricks are valid constructs when understanding the universe. Once the universe has expanded to heat death, it will have infinite size and zero mass which is the same as having 0 size and infinite mass which will cause a big bang and another universal epoch.

I'm probably remembering it all wrong, but as a layman who enjoys watching much smarter people than I contemplate and try to explain these thing, I found the idea very interesting

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[1] https://www.youtube.com/watch?v=FVDJJVoTx7s

or maybe

https://www.youtube.com/watch?v=sM47acQ7pEQ

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