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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

#211

Post by mythrwy »

lliamander wrote: post #138
galaxyLogic wrote: post #125

Earlier quoted context omitted.

Why is God a necessary thing?

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.

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

#212

Post by bobthechef »

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?

First, God is not a thing, so let's rephrase that as God is logically and metaphysically necessary.

Consider a person poking a stone around with a staff. The stone moves only insofar as the staff moves it and the staff moves only insofar as the person moves the staff. Thus, the stone moves only insofar as the person moves it. Analogously, the existence of things, here and now and at any moment, must have a cause that is causing it to be here and now or at any moment. The cause of the existence of something here and now must be other than the thing itself because a thing cannot account for its own existence. If a thing could account for its own existence, then it would need to be identical with existence. But if a thing were identical with existence, then only it could exist and nothing but it. Furthermore, no change would be possible because if a thing is its own existence, then any change could only lead from existence to something that isn't existence, i.e., non-existence. So existence precedes things and things exist here and now because it is, like the person pushing the staff, causing them to be.

We call this cause of existence God and if anything exists it necessary follows that there is a foundational cause and that is God.

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

#213

Post by jhayward »

sova wrote: post #190
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.

You have no proof that it's simply nothingness when you die. If this universe has countless beginning points, what makes you consider a single ending point would exist anywhere?

> You have no proof that it's simply nothingness when you die

Do you mean to imply that you have proof to the contrary? Why is there any reason to assume anything else?

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

#214

Post by staticautomatic »

raattgift wrote: post #110
Balgair wrote: post #88

Earlier quoted context omitted.

Sorta. We are in this thing called space-time. It came out of the Big Bang (we think). There is a finite amount of it (about 45 GLY in radius, maybe). You can only ever see about 14GLY of it due to some speed limits. You can't get to an edge or boundary of space-time because it's not 3-D, it's curved in this really weird way. There are a lot of holes in space-time that we're still thinking a lot about. For some reaso…

The hot big bang is an event in spacetime. It does not generate the manifold itself, although the geometry of the manifold necessarily reflects it, especially near the event itself. There is no evidence to support finiteness of spacetime; there is no reason why there aren't events in the infinite future. The only reason to suspect there are no events in the infinite past is a classical picture of a gravitational sing…

What does it mean for a pair of events to be mutually distant?

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

#215

Post by philipov »

bobthechef wrote: post #204
naringas wrote: post #154

Earlier quoted context omitted.

> 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…

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?

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

#216

Post by CuriousSkeptic »

octachron wrote: post #182
CuriousSkeptic wrote: post #122

Earlier quoted context omitted.

If the universe reaches a final state at one point, isn’t the implication that this is where all process that defines time ends. If so, how can one speak of things happening “after” that point?

The final state is a kind of thermal death where thermodynamics say that nothing happens anymore. However, thermodynamics is only an effective theory. It is false on tremendously large time scale: after a very very very large time a random fluctuation can bring down the universe entropy to pre-death level and restart a new non-boring universe (for a very short duration compared to the time spent in the thermal death)…

To clarify. I wasn’t arguing against there being a possibility of an “after” with new universes from nothing. I was curious about what constitutes “a very very very large time” in a universe without clocks

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

#217

Post by vokep »

jdironman wrote: post #89
sarego wrote: post #83

Earlier quoted context omitted.

Curious to know why that is. Would you mind expanding?

Because if we have not beginning, we have no purpose. If we have no purpose, this is all really for nothing. I am not arguing whether it is or not, or whether there is a beginning, but lets look at it this way... You woke up this morning, that was the beginning of this day at night you will rest. Now, lets say there is no memory or record of 'waking up' beginning, we therefor cannot anticipate an end and everything w…

I think this is a correct line of thought to a point. There is not greater purpose, and if there is, it ought to be unlike any other form of purpose. Since in general purpose is built up -- you do some task for a purpose, and that purpose is a task in some greater purpose.

As far as individual contentment, it seems maybe the truest greater purpose is actually itself: the greatest purpose is to have a greater purpose that your everyday purposes are acting towards. This gives a consistent mechanism I think, but still incomplete, or is it? Its incomplete because the "why" of the greater purpose doesn't seem to emerge from it existing. But this was mentioned at first: the why is for individual contentment, or more technically, for positive consciousness, joy, happiness, love, whatever you want to call it. The sort of existence which when you are it, you don't need or care to ask about a greater purpose, because you can feel..you know, that you're fulfilling it.

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

#219

Post by golover721 »

sova wrote: post #190
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.

You have no proof that it's simply nothingness when you die. If this universe has countless beginning points, what makes you consider a single ending point would exist anywhere?

Absolutely, and no proof that there isn’t. It certainly seems that the idea of an afterlife is appealing since in some ways it is easier to comprehend than “nothing”.

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

#220

Post by wavefunction »

nxpnsv wrote: post #144
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…

There was no "before" as time itself was created with the universe.

I have wondered in the past if "time" has varied over the existence of the Universe, like if the first 100,000,000 years relative to our own reckoning was actually more like 100 billion years as time is elastic and changed over some other higher-dimensional axis. Just a musing by a speculator
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