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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

#151

Post by philipov »

newsoul2019 wrote: post #126
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…

Is there a theory that the beginning and the ending of the universe are directly connected to each other? And that time doesn't so much start over and return to the starting point on a circle, so to speak?

Roger Penrose believes in a model he calls Conformal Cyclic Cosmology. He doesn't believe in Cosmic Inflation, and instead proposes that the accelerating expansion of our present universe forms the inflationary period of the next universe. He gets around the second law of thermodynamics by saying that the difference between the two universes is a redefinition of entropy. The mapping between the two different definitions of entropy makes our maximal entropy state look like a minimal entropy state in the new universe.

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

#152

Post by cblades »

canada_dry wrote: post #143

> Just as a shuttlecock has a diameter of zero at its bottom most point As a lay person this - right from the starting block - is what messes me up. I.e. something that exists cannot logically have a zero diameter part. Anything zero does not exist. Most related theories have similar kinds of initial premise that you must just accept.

It's a metaphor. It's not meant to be taken literally.

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

#153

Post by xenocyon »

pavel_lishin wrote: post #15
sp332 wrote: 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?

Causality is just human perception and there's nothing special about time. Let me try to explain this in three ways, going from intuitive/trivial to non-intuitive/mind-blowing:

• You can have causality in space rather than time: e.g. a convolutional image filter at pixel 13 might consider pixels 12, 13, 14 (of which the first two are causal and the last is non-causal, if we consider higher numbers as going "forward")

• You can have non-causal filters in time: e.g. audio compression at time 0:30 might consider not only the portion of audio from 0:00 to 0:30, but also the audio from 0:30 to 2:33. (This doesn't seem that remarkable, because the track has already been recorded, so it's not in "real time".)

• Finally, what we usually think of as intuitive causality in "real time" is simply a question of entropy. We think of a person dying because she was shot by a bullet, but we could also replay the movie backwards and think of all the tissues of a human body coming together in such a way as to propel the bullet backwards at a high velocity - in other words the wound causes the bullet to fly! The only reason we don't think of it this way is because the latter explanation decreases rather than increases entropy. As it turns out, physicists can show that entropy is also the exact reason why we remember the past and not the future. (And if we did remember the future and not the past, we would simply think of the future as the past and vice versa, so things wouldn't feel any different.)

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

#154

Post by naringas »

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 such a way that we can even think of these kinds of questions

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

#155

Post by swamp40 »

dugluak wrote: post #127
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…

>> Are we sitting in a ball on some gigantic alien's coffee table? sometimes I have the same question but quite opposite. What if there are miniscule worlds right on our coffee table.

Both.

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

#156

Post by Koshkin »

SubiculumCode wrote: post #106
d0m wrote: post #98

Say we could break any physical rules of our current universe, is there a good theory that would explain how something might have been created out of nothing? i.e. imagine for a second that we're in a simulation and that the current laws of physic are just arbitrary created by a "host". This "host" could have very different physical laws. Could we think of any theory that would explain the creation of something out o…

That is the most fundamental question. Why does anything exist at all? Conceptually, this question persist across all the big bangs, collapses, multi universes, or any other conception science has made informed conjectures about, doesn't require time, sequences, or cause and effect These are all processes suppose there is some underlying construct / process / force / structure. But nothing, not even the concept of no…

Yet, for many specific values of $anything the answer is very much known.

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

#157

Post by swatkat »

omarchowdhury wrote: post #7
kumarvvr wrote: post #2

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

What of Indian philosophy can you cite regarding this? From what I gather, it's seen as cyclic.

Nasadiya sukta[0] in Rigveda ponders about creation of Universe and what existed before that. Last two paragraphs (6 and 7 in wiki) are the hard-hitting ones.

[0]https://en.wikipedia.org/wiki/Nasadiya_Sukta

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

#158

Post by swatkat »

SketchySeaBeast wrote: post #42
roland00 wrote: post #35

Earlier quoted context omitted.

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 arou…

Zoroastrianism had to concept of a universe that starts with nothing and comes to an end as far back as the 6th century BCE. But I agree, adding a concrete understanding of time really helps to cement the linear narrative.

Check out Nasadiya sukta[0] in Rigveda.

https://en.wikipedia.org/wiki/Nasadiya_Sukta

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

#159

Post by DoreenMichele »

swamp40 wrote: post #155
dugluak wrote: post #127

Earlier quoted context omitted.

>> Are we sitting in a ball on some gigantic alien's coffee table? sometimes I have the same question but quite opposite. What if there are miniscule worlds right on our coffee table.

Both.

Men in Black and Horton Hears A Who: Both true tales that future generations will understand as visionaries slipping a little reality under the door of our current narrow-minded and backwards prejudices.

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

#160

Post by zarmin »

cblades wrote: post #152
canada_dry wrote: post #143

> Just as a shuttlecock has a diameter of zero at its bottom most point As a lay person this - right from the starting block - is what messes me up. I.e. something that exists cannot logically have a zero diameter part. Anything zero does not exist. Most related theories have similar kinds of initial premise that you must just accept.

It's a metaphor. It's not meant to be taken literally.

taken where?
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