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

quantamagazine.org

31–40 of 299 posts

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

#31
post #21

Cosmology is deeply disturbing if you think about it too long. Why should the universe exist? What is a causeless cause? How can something come from nothing? Regardless of the precise mechanisms involved, at some scale, some kind of steady-state cyclic model seems unavoidable --- the whole idea of existence not existing is bizarre and puzzling. The only way out of the causeless effect problem is to nop out of the eff…

That's only disturbing if you believe everything is simple enough that humans could comprehend it straight away. If you accept that some stuff is beyond our understanding, and will be for quite a while yet, everything is much less bothersome. Accept that you are fallible and the universe is fine. I'm not saying this is easy though.

> If you accept that some stuff is beyond our understanding

isn't that just an elaborate way to say 'give up'? I asked religious friends of mine about what god _is_, and the common answer is that it's beyond human understanding.

I don't believe that people should take things on faith, and accept that anything is beyond understanding.

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

#32
post #13

Earlier quoted context omitted.

You can still have causality.

Can you expand on this? How can you have causality - cause and effect - that's divorced from some sort of flow of time?

Logically, cause and effect precede time. The concept of time integrates your perceptions of cause and effect. We observe various causes and effects require variable amounts of time, we omit the specific amounts of time, thus inductively identifying the abstract concept of time.

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

#33
post #13

Earlier quoted context omitted.

You can still have causality.

Can you expand on this? How can you have causality - cause and effect - that's divorced from some sort of flow of time?

Both causality and the "flow" of time are ultimately artifacts due to the fact that a "universe", by definition, is something thay starts out in a highly-ordered state and evolves away from it. The basic laws of physics are time-symmetrical, at least in a practical sense - they do not involve any distinction between "cause" and "effect".

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

#34

Earlier quoted context omitted.

I think it might actually be more unique for western philosophy/religion to be building a narrative with a beginning, middle, and end - a lot of other ancient cultures seemed to see things as a cycle - for instance, we see in the Mayans that they saw the world as a series of cycles. It makes sense in early traditions to not have a beginning and end - if there's no track of "progress" in a historical fashion, it would…

Some of our best fictional stories are in cycles. The "Hero's Journey" is often a circle with growth, where you end up where you started from. Every season of The Wire pretty much ends in a circle.

I'm not saying they aren't, and that all narratives conceived in the west require them, but the Abrahamic (and earlier Zoroastrian) religions developed this sense of there being a definite beginning, middle, and end of everything, and that's not a concept universal to many religions.

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

#35
post #2

Curiously,Indian philosophy also propounds that the universe has neither a beginning nor an end.

I think it might actually be more unique for western philosophy/religion to be building a narrative with a beginning, middle, and end - a lot of other ancient cultures seemed to see things as a cycle - for instance, we see in the Mayans that they saw the world as a series of cycles. It makes sense in early traditions to not have a beginning and end - if there's no track of "progress" in a historical fashion, it would…

It was Aristotle's Unmoved Mover being incorporated into Christian Thought around AD 50 via Philo of Alexandria that changed Monotheistic religion of God being the Organizer of All Things from Chaos into the Creator of All Things out of Nothing, Ex Nihilo. Beforehand Monotheistic Religions believed God was a creator but he created out of chaos and imbued the formless with a specific form.

Likewise simultaneously around the time of Aristotle during the time of the Hellenistic Era, The Seleucid Empire arose from the fires of Alexander the Great Empire. The 2nd king in the Seleucid Dynasty decided to make a universal time calendar that just increments again and again past individual rulers and this change the nature of stories tremendously in the empire.

When Time Became Regular and Universal It Changed History https://aeon.co/essays/when-time-became-regular-and-universa...

When Antiochus I Soter in 281, after his father death decided to keep the calendar his father created (and he had already served 10 years as a co-ruler prior from 291 to 281.) And not start over it started the various populations that were opposed to the Seleucid authorities to tell apocalyptic tales of the end of days, not just the end of the ruler / authority but the end of everything. Especially since later Seleucid rulers such as Antiochus IV Epiphanes (175 BC to 164 BC) seem to limit Jewish religious rights, though Historians are not sure if this true (it may have been about taxes and other areas of authority.) Well there was a rebellion in 167 BC and the internal Jewish Warriors succeeded from the Seleucid Empire (The Maccabees Rebellion.) Well the rebellion was successful and they were independent for 130 years (though lots of civil wars for authority) and only in the end succumb to the Romans except the Jewish People saw the Romans at first as liberators for they still feared various Greek / Hellenistic empires and the Jewish People thought he romans were better.

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TLDR: Cyclic thinking and Creation from Something / Chaos was actually the norm in monotheism, only during the Hellenistic (Greek Influenced) / Roman Era did this shift to Creation out of Nothing (Ex Nihilo) instead of Creation out of Chaos. But yeah read the article I linked to.

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

#36
post #13

Earlier quoted context omitted.

You can still have causality.

Can you expand on this? How can you have causality - cause and effect - that's divorced from some sort of flow of time?

Our existence is limited to four dimensions, so we perceive things through the scope of time, including cause -> effect.

On the level of higher dimensions, it's difficult for us to perceive how cause -> effect would play out, but it's similar to how you would influence a drawing of a 2D stick figure. You could draw a house next to the stick figure, and that would cause the house to exist, but to the stick figure it would only perceive a single line with a start and finish on 1 dimension.

To that stick figure, cause and effect would be perceived as the two points on the line, though your four dimensional pencil caused it to exist on a different dimensional level.

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

#37
post #13

Earlier quoted context omitted.

You can still have causality.

Causality without time makes no sense. Even if you don't have a ticking clock, you can define "time" with a counter and a Lamport clock. Any time you have state, you have time. A timeless universe is hard to grasp.

Time is another dimension that we 'perceive'. Hence for our frame of reference, which is bound by time, asking what is outside this frame of reference makes no sense. But frames of references are relative and meant to be broken.

Similarly it is hard to imagine any object that can be purely 2D in nature, because we are biased to perceive the world in 3D. So we think that every object has to be 3D, even the smallest organism, or even atoms. But a 'fake' example of 2D is a tv screen. It gives us an example to imagine 2D. The point I am trying to make is that time is just our perception. To say causality is always tied to time is a bias created by viewing the universe through a 'time' tinted/colored glass.

The point of singularity where gravity is so high that time comes to stand still, but is still present - this is a possibility.

So maybe time just pauses between big bangs and flows at lower density and lower gravitational fields

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

#38

Earlier quoted context omitted.

Can you expand on this? How can you have causality - cause and effect - that's divorced from some sort of flow of time?

If I turn on a very simple computer, then the clock starts at zero. From the computers perspective that's all there is, it doesn't know the cause. From my point of view there absolutely is a case, me pushing a button. This is not a god argument, there might be natural processes that can trigger such events.

I don't think this is an accurate analogy. The computer's space-time and your space-time are the same in this analogy. The space-time that our universe exists in would not be the same as the space-time that some extra-universe process would be inside if the big bang theory is accurate. This isn't an analogy for causality without time, this is causality for the creation of our universe if the big bang theory is wrong and space-time didn't expand out of a point some billions of years ago, ie. that our space-time existed "before" the big bang and there were processes outside of our universe that were still inside of the same space-time as ours.

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

#39
post #13

Earlier quoted context omitted.

You can still have causality.

Causality without time makes no sense. Even if you don't have a ticking clock, you can define "time" with a counter and a Lamport clock. Any time you have state, you have time. A timeless universe is hard to grasp.

Time flows in a similar way throughout the universe. It might be slowed down by gravity here and there but it's a similar effect everywhere. With causality but not time, there would be a partial ordering of events that happened at a particular location, but no definite way to connect it to events that happened elsewhere using relativity like we're used to now.

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

#40

What does it even mean to ask “what happened before time”? The question seems nonsensical to me.

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.
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