Stephen Hawking Latest Theory

[hazelm]

Stephen Hawking's latest and last publication is out today.  His final theory of the universe,  about the big bang, is (surprisingly to me, at least) based on the string theory.

 

The theory, which was submitted for publication before Hawking's death earlier this year, is based on string theory and predicts the universe is finite and far simpler than many current theories about the big bang say.

 

https://www.sciencedaily.com/releases/2018/05/180502094641.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Ftop_news%2Ftop_science+%28ScienceDaily%3A+Top+Science+News%29

Edited May 3, 2018 by hazelm

[JMJones0424]

I can't make heads or tails from this article.  It seems to me that the claim is that our universe can be described as a hologram, for whatever use this is, and that the Big Bang is a boundary condition.  F me if I understand what this means.

 

 

"We are not down to a single, unique universe, but our findings imply a significant reduction of the multiverse, to a much smaller range of possible universes," said Hawking.

This makes the theory more predictive and testable.

I'm lost.

[hazelm]

I can't make heads or tails from this article.  It seems to me that the claim is that our universe can be described as a hologram, for whatever use this is, and that the Big Bang is a boundary condition.  F me if I understand what this means.

 

 

 

I'm lost.

I never have been able to fathom  holograms.  So, I skip that.  But for the rest, I see it exactly as you do.  Good to know that you see the same thing.  Means we are on the right track.  Yes?  :-)

[JMJones0424]

If by the right track you mean that we are together clueless, then I suppose so.  I bet that the writer of the article you linked to is also an unwitting passenger on our train.

[hazelm]

If by the right track you mean that we are together clueless, then I suppose so.  I bet that the writer of the article you linked to is also an unwitting passenger on our train.

No, I do not mean clueless.   I mean I understand what he is describing. And I get the impression that you also understand what he is saying.  You perhaps just don't see the idea as the writer (or perhaps Hawking) did.   It is up to others far better than I to find any weaknesses in the theory.  Or, as another thread here (which has gone on far too long) says, is it falsifiable? 

[JMJones0424]

Be gone you devil temptress.  The falsifiability of the claim is entirely separate from the veracity of the claim.  It just so happens that it's pretty hard to make the case for the falsifiability of the claims in this article.  However, I claim ignorance, so falsifiability or not, while I can understand what a hologram is, and I can understand that the information contained in a blackhole is projected on its edge like a hologram, and I can understand that if we lived inside a blackhole we won't be able to show otherwise, I still can't claim to understand any of this.

 

Clueless is perhaps too harsh.  Instead, I claim profound ignorance.  I understand just enough to know that I don't have any freaking clue.

 

EDIT: A hologram is a two dimensional representation of a three dimensional object.  https://en.wikipedia.org/wiki/Holography  

Drop the Star Wars connotation and understand that you can draw a representation of a cube, a three dimensional object, on a piece of paper, a two dimensional object.  It is my understanding that a hologram conserves information in one less dimension, in much the same way that we can draw an example of a cube on a piece of paper.

Edited May 3, 2018 by JMJones0424

[hazelm]

Be gone you devil temptress.  The falsifiability of the claim is entirely separate from the veracity of the claim.  It just so happens that it's pretty hard to make the case for the falsifiability of the claims in this article.  However, I claim ignorance, so falsifiability or not, while I can understand what a hologram is, and I can understand that the information contained in a blackhole is projected on its edge like a hologram, and I can understand that if we lived inside a blackhole we won't be able to show otherwise, I still can't claim to understand any of this.

 

Clueless is perhaps too harsh.  Instead, I claim profound ignorance.  I understand just enough to know that I don't have any freaking clue.

 

EDIT: A hologram is a two dimensional representation of a three dimensional object.  https://en.wikipedia.org/wiki/Holography  

Drop the Star Wars connotation and understand that you can draw a representation of a cube, a three dimensional object, on a piece of paper, a two dimensional object.  It is my understanding that a hologram conserves information in one less dimension, in much the same way that we can draw an example of a cube on a piece of paper.

That works out fine.  I don't understand those things you understand and you don't understand those things I understand.    Hawking has written a bit about this before which is why I think I understand because - in my ignorant  intelligence about science - I  once "created" (note quotes) a  theory of black holes being recycling plants for - not universes but - stars and galaxies.  I had quite a dream until an astronomer kindly set me straight.

 

All right.  Stephen Hawking had a book titled "Black Holes and Baby Universes  and other Essays".  I have not read all of it yet but he has quite an idea about things that fall into black holes and how they escape as the holes shrink.  Airplanes, if I remember rightly, escape and have their own little universes.  When these things escape, the holes shrink to nothing but we see these new universes as other black holes.

 

Now, who would have thought a scientist - especially a physicist - would have such an imagination?  On the other hand, is he the scientist that I once read did not much care about quantum mechanics?  Don't take my word for that.  I read it about some physicist but not sure now who it was.

 

There is a black hole outside my window now.  Even the moon is hidden.  I'd best be away. Good night.

[JMJones0424]

Now, who would have thought a scientist - especially a physicist - would have such an imagination?  On the other hand, is he the scientist that I once read did not much care about quantum mechanics?  Don't take my word for that.  I read it about some physicist but not sure now who it was.

I don't know what specific thing you are remembering, but it is likely to be a statement by Einstein, as while his discoveries led to quantum mechanics, he remained convinced that the consequences of his discoveries did not lead to the uncertainty of quantum mechanics.  The famous quote is "God does not play dice".  But, there is every reason to believe that reality is in fact dictated by statistics rather than absolutes.  The idea that Einstein held ideal was that if we know the condition of the cosmos and that we know all the influences on the cosmos, then we can make accurate predictions about future instances and we can infer past instances.

 

Quantum mechanics shows this claim to be false, because inherent in reality is a measure of chance.  So, regardless of how well we measure the current state, and regardless of how well we describe how things change, we can not fully predict the future state and we can not fully infer the previous state.  God, if such a thing could be shown to exist, only plays dice.

[hazelm]

I don't know what specific thing you are remembering, but it is likely to be a statement by Einstein, as while his discoveries led to quantum mechanics, he remained convinced that the consequences of his discoveries did not lead to the uncertainty of quantum mechanics.  The famous quote is "God does not play dice".  But, there is every reason to believe that reality is in fact dictated by statistics rather than absolutes.  The idea that Einstein held ideal was that if we know the condition of the cosmos and that we know all the influences on the cosmos, then we can make accurate predictions about future instances and we can infer past instances.

 

Quantum mechanics shows this claim to be false, because inherent in reality is a measure of chance.  So, regardless of how well we measure the current state, and regardless of how well we describe how things change, we can not fully predict the future state and we can not fully infer the previous state.  God, if such a thing could be shown to exist, only plays dice.

That was it!  Yes!  Thank you.  As for your second paragraph, I do not know much about quantum mechanics - if anything.  It probably has nothing to do with what I think.  I.e., The future is always one of chance.  That's a given whether it relates to quantum mechanics or not..  Try predicting the weather.

 

Just my thought. 

[JMJones0424]

Predicting the weather is a very good example.  Einstein's view of reality held that if we could accurately measure the current state, and if we could accurately describe how that state changes, then we should be able to predict precisely how much rain will fall in a particular place.  Statistical views of reality like quantum mechanics shows that such an exact prediction is impossible, instead, the best we can do is make a statistical prediction.

[hazelm]

Predicting the weather is a very good example.  Einstein's view of reality held that if we could accurately measure the current state, and if we could accurately describe how that state changes, then we should be able to predict precisely how much rain will fall in a particular place.  Statistical views of reality like quantum mechanics shows that such an exact prediction is impossible, instead, the best we can do is make a statistical prediction.

Right.  I just didn't relate it to quantum mechanics.  Some day I'll have to delve into QM.  I thought it referred to the quarks, etc.  But, isn't Einstein's idea of measuring to exactness  the kind of thing I was thinking of when I said Hawking had a wonderful imagination for a physicist who - I would think - would want to be exact? 

Edited May 8, 2018 by hazelm

[JMJones0424]

I don't know.

 

We may all like to be exact in our imagining, but I am not sure that such a wish is possible, specifically because physics is a statistical pursuit rather than an absolute pursuit, especially if you are a cat in a box.  My understanding of Hawking's claims are limited to my insufficient understanding and to his published books, which I highly recommend.  A Brief History of Time is a book that I would bet nearly everyone that is interested in physics has read.  His genius is beyond my understanding, but what I find genius is the fact that he can make complicated subjects understandable to laymen.

[hazelm]

I don't know.

 

We may all like to be exact in our imagining, but I am not sure that such a wish is possible, specifically because physics is a statistical pursuit rather than an absolute pursuit, especially if you are a cat in a box.  My understanding of Hawking's claims are limited to my insufficient understanding and to his published books, which I highly recommend.  A Brief History of Time is a book that I would bet nearly everyone that is interested in physics has read.  His genius is beyond my understanding, but what I find genius is the fact that he can make complicated subjects understandable to laymen.

I was at a humongous book fair last Saturday and picked up two of his books:  "A Brief History of Time" and "Black Holes and Baby Universities - and other essays".   If "genius is the ability to make complicated subjects understandable",  I have been lucky to know several such geniuses and am grateful to them.  

 

By the way,  I have a book by Einstein about relativity.   "Relativity - The Special and the General Theory", written in 1916.  This is a special book  due to his purpose with it.  In his preface he says  his intention is to "give an insight into the theory of Relativity to those who are interested in the theory from a scientific and philosophical point of view but who are are not conversant with the mathematical apparatus of theoretical physics".

His attempt was to explain his theory without using any math.  He almost did it.  He got right near the end when he resorted to math equations. 

 

Genius, indeed. 

[JMJones0424]

Special Relativity seems obvious, in hindsight.  Start with the fact that the description of an event must include three dimensions plus time.  For example, meet me at the corner of 25th avenue and 10th street on the second floor at 2 pm.  Add to this that the speed of light is measured to be the same regardless of your velocity.  If such a thing is true, then in order to transform positions that can be universally recognizable, given the fact that light speed is constant, then all other measurements must be relative.  Once you cross this hurdle, regardless of whether or not you can do the math, then you are primed for the next step.

 

GR claims that gravity imparts an acceleration on all massive objects.  An acceleration changes how an object moves through space.  If you combine the fact that an object can be described by its three dimensional location and time, and you can understand that the speed of light is constant, then you must conclude that every coordinate is conditional depending upon the reference frame from which you are measuring.  And, since gravity is an accelerating force, then the closer you are to a massive object, the greater the distortion of this coordinate system.

 

There are many instances outside of physics of coordinate changes.  For instance, when I was a Marine and called in artillery, I used my latitude, longitude, and elevation as a base point from which to determine the target.  I would give the azimuth, range, and elevation to the target from my position.  The artillery would then convert their position to mine and add in the corrections I called in to accurately hit the target.  This is what transformation is.

 

Lorentz transformation is the way that we can change from the coordinate system we use to the coordinate system that another person that is traveling faster than we are would use to describe our position.  If we set the speed of light as constant, regardless of one's velocity, as has been shown to be the case, then all other coordinates including length and passage of time must be variable.  This is Special Relativity.

 

General Relativity is the description of how the proximity to a massive object changes the shape of my movement through space.

Edited May 8, 2018 by JMJones0424

[Shustaire]

 The overall purpose of the paper is to solve a common problem with inflationary models called "Runaway inflation" slow roll is one mecaanism that attemppted to solve this problem however did not sufficiently work under the eternal inflationary model. From what I gather from the paper the boundary conditions are being used to prevent runaway inflation leading to a multiverse or rather multiHubble bubbles.

 

 This isn't the greatest article but it does describe the runaway inflation problem

 

https://escholarship.org/uc/item/3tn352x2

 

Hoe that helps I'm incredibly busy, with my students and heling my Hubby with his research project, so it may be some time before I can visit this site again.

Edited May 9, 2018 by Shustaire

[Farsight]

I'm afraid Hawking was rather more popular with the media than with serious physicists and cosmologists. See this physicsworld article for a hint of that: https://physicsworld.com/a/by-hamish-johnstonstephen-hawk/

 

"There is just one tiny problem with all this – there is currently little experimental evidence to back up M-theory. In other words, a leading scientist is making a sweeping public statement on the existence of God based on his faith in an unsubstantiated theory".

 

There's no evidence to back up his claims I'm afraid. It's all very speculative. Of course people don't like to be critical, especially following recent events. Hence you shouldn't expect to hear too much about Hawking's last paper.   

Edited May 10, 2018 by Farsight

[JMJones0424]

Meh.  The problem is that it is very hard to test, if it can be tested at all.  Of course it's speculative, speculation is exactly what led to string theory and M-theory and the concept of the multiverse.

 

There is no evidence, and may not ever be evidence to support the claim.  Imagine that you were on a planet observing the cosmos 100 billion years in the future or a sufficient enough amount of time that inflation would have red-shifted out every galaxy other than your own.  It would be accurate to point out that it is impossible to test for the existence of distant galaxies.  You probably wouldn't even understand the concept of galaxies, since your entire observable universe consisted of the galaxy you are trapped in.  However, your failure to test for the existence of additional galaxies does not change the fact that these galaxies could exist.

 

The point is that it is (or should be) a mathematically consistent explanation of observations that we have made and could possibly make.  If you're looking for falsifiable claims, then you probably shouldn't be looking in theoretical physics.  I understand that this seems like hand-waving, and if you insist on testable explanations, then it might as well be just a bunch of hocus-pocus.  However, there is something to be said for extending mathematical representations of our reality into that which we can not currently test.  Quite a bit of the advancements we have made in the last hundred years were by those trying to test previously untestable models and to adjust our explanations after new tests had been made.

 

I can't imagine a test for M-theory, but I'm an idiot.  Most (all?) theoretical physicists can't imagine a test for M-theory either.  The sad truth is that it may both be accurate and untestable.  I can not fault you for refusing to accept its accuracy because it is untested, this is simply good skeptical thinking.  However, likewise, you can't rule it out since it does seem to explain currently observed phenomena.  Perhaps you can offer a better explanation?

 

I'm afraid that while media popularity isn't a good measure of a physicist's work, Hawking is not in the same class as some like Michio Kaku or even Hamish Johnston.  I did not find any papers on arxiv that included Johnston as an author, nor could I find anything with a quick google search.  You can find, easily, how Hawking has contributed to physics with a simple search.  You may rightly argue that M-theory is not testable at this time, but you can't argue that Hawking was just some media hack.

 

The worst thing you could do, however, is to accept Hawking's last paper because he just died.

Edited May 12, 2018 by JMJones0424