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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

#71

Earlier quoted context omitted.

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…

Good point which brings us to a simple explanation. Time zero isn't when the h/w is booted, it's when the software is started. As unpopular as the simulation theory is, many difficult issues can easily be thought about. Except for the rest of the turtles.

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

#72

I have very little knowledge of astrophysics, but I thought it would be an interesting idea if the universe constantly recycled itself. That is, every so often it collapsed in on itself and produced another big bang. Theoretically some parts of the universe would have already achieved escape velocity, but the rest of it is gradually gravitating towards some center of mass. Is such a thing even feasible?

[deleted]

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

#73

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…

> There is also a theory there could be many other big bangs and universes next to our own, but they are all accelerating away from each other. I speculate that there is. And I assert that for our universe to be meaningful, it must birth a sentience into life in the fourth dimension. That probably sounds very wishy washy but does anyone get what I mean and agree with me on this? I’ve never told anyone about this post…

You're not alone in thinking this at all.

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

#74
A part of me wonders if the disproportionate weightage of particular scientists/researchers skews the field toward their ideas more than others.

As far as i can tell, the Vatican proposal by Stephen Hawking is a hypothetical, one that has math going for it, but in a case considered by the opponents, going against it. The consensus of the community of scientists backing Hawkings hypotheticals could as easily have backed the opposing view, but there you have it, its considered the accepted view of reality. Why? I can't reasonably explain that to someone less tuned in to the physics community, but there it is.

Reminds me of a conversation over drinks with a colleague of mine who i know to delve in alternate theories talking to me about Birkeland Currents[1] and how "popular science" favored the theories of (coincidentally) another British scientist for the longest time, thus leaving the author of the (later proved) correct theory, shunned for decades by the scientific community.

[1]: https://en.wikipedia.org/wiki/Birkeland_current

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

#75

Earlier quoted context omitted.

The word is 'speculation' not 'belief' that that's pretty much what all science is. The evidence usually comes later.

Agreed that is where science starts. Speculation leads to generating testable hypotheses and experiments.

Not in the case of string theory.

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

#76
post #51

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…

> 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, there are most likely more stars, planets and gas.

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

#77

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.

Can we follow this a little further?

Let’s say you and me are little bits of algae which are floating in blob in the ocean off the coast. We are in a larger current which we cannot see. The current is such that we will eventually strike the shore together.

We are in a cluster of material together. It’s not exactly algae, there are a bunch of random gels, some mostly decomposed skin parts. Some very fine grit.

Of course the ocean is constantly mixing everything up, so even though we have been in this blob together for several weeks, that’s not exactly normal.

Well, there millions of blobs like ours, so I guess it’s sort of normal. But there are a quadrillion billion blobs that won’t last the hour. So our blob is, if not abnormal, improbable.

You and I are algae, so we can’t sense much. But we have noticed many events over our lives. Very early in our lives we perceived the day cycle. There are good times to photosynthesize, boy did we feel that. Time. We noticed quite a few bacterial... situations. And geometrically there have been a number of events in our blob. It used to be much bigger, for one thing. We certainly noticed every time a chunk got taken out of the blob and the energy gradients went haywire.

Of course we’re algae so we don’t remember, but we notice.

There is a world outside our blob, but we cannot know it. Sadly, this is physics. There’s not enough atoms in the blob to make a fin, let alone an eye or a brain. So there will be no peering out of the water at the sky. We can sense events within the blob. Outside the blob there may be more going on, but we certainly can’t see it.

There are unexplainable patterns in the blob. Why does it look sheared off on two sides? “We”, meaning our limited algae consciousnesses, didn’t exist during those events so we are just as cut off from our past as we are cut off from the world around us.

And we are barreling now, in a wave towards the shore.

And now we are floating.

And now we are rolling through a wave towards the shore.

And now we are slipping calmly on the surface.

And soon we will crash onto the sand, where we will be consumed by bacteria and insects, and our blob will be no more.

It is inevitable. The first law of algae says: you will be eaten.

But we will not be eaten this minute. And so I ask you: what happened in the blob, before it existed?

Luckily, though we can’t see outside the blob, we can ponder questions like this, because we are hypothetical blobs, and hypothetical blobs have human brains!

We can certainly guess what our bodies were before the blob existed. They were a cloud phosphorous and nitrogen. And presumably there were other plants or bacteria in our proto-blob that produced those nutrients for to become us.

That bit of skin I mentioned was on a dead whale. It was on the ocean floor but it got kicked up to the surface in a storm.

The gels came from jellyfish. And the salty water around us... well, it was salty water.

What shape was all that stuff in? A strange one. But still, we could draw it if we had some art supplies. And fingers. The current that brought in the whale skin could be drawn to an approximation. The bacteria largely came from two identifiable blooms, plus a long tail of about a thousand others, plus an unknowable tail catalog of origins describing the last 0.001% of bacteria in our blob. We couldn’t draw that, but maybe a light watercolor fog around our greater vicinity could represent it.

If I could draw our blob before it existed, it would look like a strange flower. With very long tendrils but also several beautiful simple twisted surfaces.

Now, what about the universe itself?

Science suggests its origins were not nearly so “soft”. Our blob was sort of “assembled” from pre-blob parts. The universe doesn’t appear to have been assembled in a soup that same way. Trend lines suggest it started as a singularity, not an assemblage.

But all physicists will admit we don’t have the technology to peer into those first moments. Like us and our blob, there’s just not the equipment available to look outside the universe to get data, nor was there equipment present to remember things as they happened.

We just don’t know what physics is like in those kind of moments. Is it an assemblage of parts from a larger vicinity? Are there even larger vicinities than our blob?

Or, to put it in terms that you and I would understand: did the universe, at birth, have a bit of whale skin in it? Some dead jellyfish bodies?

We can only speculate. As for me I say: why not?

But I’m just a bit of algae. What do I know.

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

#78

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

It helps to think of time as change. Time started when the first thing changed. So to say there was no beginning helps by not having to answer what the first change was ot why it did. It's still hard to imagine no first change without an infinite regress. Maybe if you think of it reletivistically as in there wasn't a singular beginning but a beginning area where depending on where you are it could be a beginning but not the beginning.

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

#79

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…

> There is also a theory there could be many other big bangs and universes next to our own, but they are all accelerating away from each other. I speculate that there is. And I assert that for our universe to be meaningful, it must birth a sentience into life in the fourth dimension. That probably sounds very wishy washy but does anyone get what I mean and agree with me on this? I’ve never told anyone about this post…

Anthony Aguirre at UCSC does research in this area:

https://arxiv.org/pdf/0712.0571.pdf

http://scipp.ucsc.edu/~aguirre/Research.html

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

#80

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.

Agreed with the Zoroastrianism bit, that did occur prior.

I was trying to be simple and concise so I did not mention other strands of monotheism that influenced Judaismm and the Middle East such as the Egyptians / Amun (the Hidden One) or the Persian Zoroastrianism (which pioneered the concept of Angels as winged divine beings that Judaism and Christianity incorporated.) Yadda, yadda, yadda religion and history is complicated but also interesting.

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