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Author Topic:   Is the “Fine-Tuned Universe” an Illusion?
Tangle
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Posts: 9489
From: UK
Joined: 10-07-2011
Member Rating: 4.9


(3)
Message 46 of 61 (891857)
02-14-2022 3:58 PM
Reply to: Message 39 by jar
02-14-2022 8:40 AM


Re: Full justification for EvC's existence.
jar writes:
The last few days posts in this thread IMHO are full and complete justification for EvC's existence.
The thread has been a classic example of Evolution in action.
You may well say that, I haven't a clue what old Gokkie is saying, but I defend his right to confuse the fuck out of me.

Je suis Charlie. Je suis Ahmed. Je suis Juif. Je suis Parisien. I am Mancunian. I am Brum. I am London.I am Finland. Soy Barcelona

"Life, don't talk to me about life" - Marvin the Paranoid Android

"Science adjusts it's views based on what's observed.
Faith is the denial of observation so that Belief can be preserved."
- Tim Minchin, in his beat poem, Storm.


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AZPaul3
Member
Posts: 8513
From: Phoenix
Joined: 11-06-2006
Member Rating: 5.3


Message 47 of 61 (891858)
02-14-2022 7:05 PM
Reply to: Message 45 by Son Goku
02-14-2022 2:02 PM


Many Worlds
Many worlds (MW), I am informed, does away with any wave function collapse. Determinism and objective reality are preserved. My layman’s problems with MW include … the many worlds. That is too far outside my comfort zone. Please excuse the personification but after decades I am still trying to resolve this stuff in my own head.
You said in one early message that you thought MW was completely silly.
But, just as with QM, there are rigorous mathematical, logical, recognized genius stuff reasons to give MW considerable credence. From what I can see, not just cosmologists like MW. Lots of recognized world-class egg heads work on extra dimensions, symmetries, etc. It gives them a new playground. Their goals, as I understand their science outreach work, is to crack the nut of quantum gravity, as is everybody’s goal.
So what I see is a lot a really smart people, recognized big names in physics, all with different ideas of what reality may and may not be. That right there tells us something is fundamentally wrong. The fragmentation says, to me, that we haven’t found the reality. We are still missing something. [feign surprise]
The tools are super fantastic. Indeed, for this universe, QM/QFT are … well … productive … on steroids.
Intellectually, I can understand, but not accept, the deeper weirdness(es) the different camps are offering. I also harbor a long held aversion to anything that tilts at the windmill of objective reality. Of the various craziness(es) offered I would have a preference for MW knowing, despite the insistence of the MW advocates, those many worlds are our philosophical contrivances and may not exist in reality at all. I can accept that. MW restores my beloved objective reality.
Still, I am left with the angst that our views on reality are not the reality.

Eschew obfuscation. Habituate elucidation.

This message is a reply to:
 Message 45 by Son Goku, posted 02-14-2022 2:02 PM Son Goku has replied

Replies to this message:
 Message 51 by Son Goku, posted 02-15-2022 3:35 AM AZPaul3 has replied

  
xongsmith
Member
Posts: 2578
From: massachusetts US
Joined: 01-01-2009
Member Rating: 6.8


(1)
Message 48 of 61 (891859)
02-14-2022 7:20 PM
Reply to: Message 46 by Tangle
02-14-2022 3:58 PM


Re: Full justification for EvC's existence.
Tangle writes
I haven't a clue what old Gokkie is saying
Pardon me, but isn't this the Son of old Gokkie?
Says so right in his name... "Son Goku"
Sorry...sometimes I can't help myself...

"I'm the Grim Reaper now, Mitch. Step aside."

- xongsmith, 5.7d


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jar
Member (Idle past 394 days)
Posts: 34026
From: Texas!!
Joined: 04-20-2004


Message 49 of 61 (891860)
02-14-2022 7:42 PM
Reply to: Message 48 by xongsmith
02-14-2022 7:20 PM


Re: Full justification for EvC's existence.
When is the electron not an electron?

My Website: My Website

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AZPaul3
Member
Posts: 8513
From: Phoenix
Joined: 11-06-2006
Member Rating: 5.3


Message 50 of 61 (891861)
02-14-2022 8:37 PM
Reply to: Message 49 by jar
02-14-2022 7:42 PM


Re: Full justification for EvC's existence.
When it's moving backward through time. Then it's a positron.

Eschew obfuscation. Habituate elucidation.

This message is a reply to:
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Son Goku
Inactive Member


(5)
Message 51 of 61 (891864)
02-15-2022 3:35 AM
Reply to: Message 47 by AZPaul3
02-14-2022 7:05 PM


Re: Many Worlds
Many worlds (MW), I am informed, does away with any wave function collapse. Determinism and objective reality are preserved
You said in one early message that you thought MW was completely silly
For specific mathematical reasons. It's nothing to do with the idea that multiple alternate timelines is inherently silly.
Many Worlds is a specific idea that requires certain theorems to hold up in order to work. After over sixty years they never have. For that reason I find continued investigation of it to be pointless. There have been several examples recently where it seems impossible to get any numbers (let alone the correct ones) out of it.
It's just a pile of words rather than a cogent idea.
I have found on the internet many of these ideas, e.g. Bohmian Mechanics, Many Worlds, get far more coverage than they do in actual physics research. So this can make them seem more prominent than they really are. Open an academic book on the Fundamentals/Interpretation of Quantum Mechanics like Asher Peres' "Quantum Theory: Concepts and Methods" or Roland Omnès' "The Interpretation of Quantum Mechanics" with thousands of citations each and you'll see Many Worlds and Bohmian Mechanics dismissed in one or two paragraphs.
Lots of recognized world-class egg heads work on extra dimensions, symmetries, etc. It gives them a new playground
That stuff has nothing to do with Many Worlds. Spacetime having additional dimensions, or finding new symmetries is unrelated to the Many Worlds idea.
The fragmentation says, to me, that we haven’t found the reality. We are still missing something
But none of this really involves a questioning of QM back in the direction of "objective" physics. They have disagreements over the exact form of where Quantum Gravity should go, but nobody highly cited in the field is actually proposing a return to the objective picture of the world. In fact most like Nima Arkani-Hamed, Raphael Bousso or Thomas Banks or hundreds of others I could name are advocating that it should be more subjective.
MW restores my beloved objective reality
As I said above the issue is it doesn't work. And there was never any scientific motivation for it aside from this intellectual prejudice.
In summary:
Objective reality has turned out to be empirically incorrect. In Quantum Mechanics you can show that large scale features of objects, like those in the day to day world, are capable of being objectively described. However at a fundamental level the world is not. One has to get used to it just like several other scientific ideas that changed our view of the world
Edited by Son Goku, : Typo

This message is a reply to:
 Message 47 by AZPaul3, posted 02-14-2022 7:05 PM AZPaul3 has replied

Replies to this message:
 Message 52 by AZPaul3, posted 02-28-2022 1:08 AM Son Goku has replied

  
AZPaul3
Member
Posts: 8513
From: Phoenix
Joined: 11-06-2006
Member Rating: 5.3


Message 52 of 61 (892149)
02-28-2022 1:08 AM
Reply to: Message 51 by Son Goku
02-15-2022 3:35 AM


Re: Many Worlds
Objective reality has turned out to be empirically incorrect.
Not quite. Objective reality has been "interpreted" to be incorrect by one school of QM.
But none of this really involves a questioning of QM back in the direction of "objective" physics. They have disagreements over the exact form of where Quantum Gravity should go, but nobody highly cited in the field is actually proposing a return to the objective picture of the world. In fact most like Nima Arkani-Hamed, Raphael Bousso or Thomas Banks or hundreds of others I could name are advocating that it should be more subjective.
Yes, indeed, the copenhagen interpretation is the leading hypothesis. But it is not a solid consensus of the discipline. There are major schools of disagreement. At this point the popularity contest is not definitive.
In Quantum Mechanics you can show that large scale features of objects, like those in the day to day world, are capable of being objectively described. However at a fundamental level the world is not.
QM is internally inconsistent in it's definition of a measurement. What is a measurement? What happens when a measurement occurs?
Copenhagen operates under such a regime that objective reality, not just an unknown, is called into question. Others do not.
Fundamental levels? I submit we aren't there yet. We can make QM/QFT work so very well, exceptional accuracy, modern magic, but we don't know how measurement works or why it works. One view is to say hang the lot of it, reality doesn't matter, just shut up and calculate. Very productive but very inane.
I expect more. The smart guys have a lot more study to do.
In the meantime Copenhagen's measurement problem persists as its interpretation of that problem is inconsistent and questionable.
The internal inconsistency shows the theory in not complete and needs to be adjusted. My hope is that QM will adjust itself into a nice warm comfortable objective reality. With a cup of tea.
One has to get used to it just like several other scientific ideas that changed our view of the world.
And will change again we can be sure.
Here is a video with a much better explanation of the issue involved. It is not a settled matter in the discipline.
Dr. Sabine Hossenfelder is a respected physicist that has taken up science outreach. She still works at CERN and at the Frankfurt Institute for Advanced Studies where she leads the Superfluid Dark Matter group.
Edited by AZPaul3, : No reason given.

Edited by AZPaul3, : No reason given.


Eschew obfuscation. Habituate elucidation.

This message is a reply to:
 Message 51 by Son Goku, posted 02-15-2022 3:35 AM Son Goku has replied

Replies to this message:
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Son Goku
Inactive Member


(2)
Message 53 of 61 (892150)
02-28-2022 7:36 AM
Reply to: Message 52 by AZPaul3
02-28-2022 1:08 AM


Re: Many Worlds
I'll take the statements out of order from your original post.
QM is internally inconsistent in it's definition of a measurement. What is a measurement? What happens when a measurement occurs?
This is not true. It's fairly clear in the theory what happens when a measurement occurs. There's a mathematical operation to describe how a measurement affects the state of the system.
The technical name for this mathematical structure is a Kraus operator, although when students take their first course in quantum mechanics we usually simplify it to something called a projection operator. The technical details don't matter so much for a forum post here, the point is more that it's fairly clear what happens when a measurement occurs, I've taught it several times and it pops up usually the first three chapters of an undegraduate QM book. If the theory couldn't describe how to deal with measurements it wouldn't be empirically valid.
Furthermore QM can be derived as a set of statements about measurements, i.e. its rules for describing measurements are in fact the core of the theory from which the rest can be derived. This is covered in recent books like Jochen Rau's "Quantum Theory: An Information processing approach" and D'Ariano's "Quantum Theory from First principles". It's even covered in detail in older books like Julian Schwinger's "Quantum Mechanics: Symbolism of Atomic Measurement" and Asher Peres' "Quantum Theory: Concepts and Methods".
So quantum theory has a very clear notion of what occurs upon a measurement and nobody has ever shown an actual internal inconsistency.
Some people don't like measurement being a primitive, but that's different from a mathematical inconsistency.
Copenhagen
....
But it is not a solid consensus of the discipline
.....
Objective reality has been "interpreted" to be incorrect by one school of QM
You said phrases like this a few times in your post.
"Copenhagen" usually refers to the specific approach to quantum theory discussed by Heisenberg, Bohr, Peierls, Pauli, von Weisacker, Ludwig, Born, etc. Essentially the understanding of the theory by the people who discovered it, as well as others after them such as Julian Schwinger.
I never specifically referred to this. In fact my favourite way of looking at the theory is that of the French physicist Roland Omnès called Consistent Histories. It doesn't really matter because although there might not be an exact consensus on whether literally every aspect of Copenhagen is correct, there is very little debate about a return to objective reality by people who discuss the fundamentals of quantum theory. It's not just one school that comes away from objective reality, it's virtually all of them. It's really impossible to understand how somebody could maintain it when you know the theory well due to results like the Kochen-Specker theorem, the Unruh effect and so on. That's why most people, even if they don't completely agree with Bohr, rarely argue for objective reality or measurement independent values.
Added to this is that the people that advocate a return to an objective reality have no working theory that actually matches observations.
In fact most of the people who disagree with Copenhagen think Bohr wasn't subjective enough.
The internal inconsistency shows the theory in not complete and needs to be adjusted
Again I have never seen this "internal inconsistency".
Fundamental levels? I submit we aren't there yet. We can make QM/QFT work so very well, exceptional accuracy, modern magic, but we don't know how measurement works or why it works. One view is to say hang the lot of it, reality doesn't matter, just shut up and calculate. Very productive but very inane.
I expect more. The smart guys have a lot more study to do.
Sorry AZPaul3 but I honestly view this as somewhat anti-scientific.
We physicists don't just think "reality doesn't matter". It's that we have seen a theory that jettisons objective reality, quantum theory, matches experimental results and there is no working theory that retains objective reality. Further as physics has advanced since Heisenberg's rejection of objective reality we have had to remove more and more elements of objectivity from our theories.
The realisation that reality lacks an objective description is an advancement in our understanding of reality. Going on about how a theory and the people who use it are "inane", have "more study to do" and you personally "expect more" is just anti-scientific rhetoric about a theory being poor because it doesn't match your metaphysical predilections regardless of how empirically successful it is.
Here is a video with a much better explanation of the issue involved. It is not a settled matter in the discipline.
I know both Hossenfelder, I have met her, and the experiment she is discussing. I'll only say:
(a) I don't see any reason why she is focusing on this experiment when the hundreds of experiments on the Kochen-Specker theorem, GHZ theorem, etc already show the existence of an objective description of reality is untenable. I don't think she analyses this experiment correctly. Ultimately her objection just amounts to that the experiment doesn't show a lack of objectivity at the human level. All of us know this. As I said above large scale features of the world are known to support an objective description. That's why Classical Mechanics works. The experiment does show however the lack of an objective description at the atomic level. One of hundreds that does so.
(b) She herself has started advocating nonsense like superdeterminism, an idea that involves rejecting basic aspects of scientific thinking. Again just because quantum theory doesn't fit her metaphysical preconceptions.
Again all I can say to you is look at the actual literature. Roland Omnes, Asher Peres, Bernard d'Espagnat, Werner Heisenberg, Rudolf Haag, all of them and several others have highly cited (thousands of citations) monographs explaining why you have to give up objective reality. To me it is a settled matter scientifically. It's only unsettled under the trivial criterion of "there exists some people saying otherwise in youtube videos and some pop science books". I mean then we could say evolution is not a settled matter in the discipline of biology due to the presence of creationist academics.
Edited by Son Goku, : Typos

Edited by Son Goku, : Details


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Son Goku
Inactive Member


(1)
Message 54 of 61 (892163)
02-28-2022 3:57 PM


Experimental tests of Objective Reality
Actually for anybody wondering, just to provide a brief explanation how one can actually experimentally refute objective reality. It comes in two forms.
First of all, since quantum mechanics rejects the idea of an objective reality any experimental test in support of it is in a sense experimental evidence that objective reality is wrong.
However a more interesting case are the so called "no-go theorems". These are various mathematical proofs that show that a given experiment has to give results within a certain range if the idea of an objective description of reality is correct. The theorems have different names depending on the exact type of experiment they give constraints to, some examples include CHSH, GHZ, Kochen-Specker, Aravind-Mermin. The video by Hossenfelder concerns a recent such no-go result called Brukner's theorem.
When we have done these experiments the results break the constraints that follow from assuming an objective description of reality. Which means even if QM were wrong, objective reality wouldn't be right. The theory needed to replace QM would be another non-objective theory because these "no-go" experiments provide a test of objective reality independent of QM.

Replies to this message:
 Message 55 by Tanypteryx, posted 03-05-2022 9:30 PM Son Goku has replied

  
Tanypteryx
Member
Posts: 4344
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 5.9


Message 55 of 61 (892351)
03-05-2022 9:30 PM
Reply to: Message 54 by Son Goku
02-28-2022 3:57 PM


Speed of Light = Speed of Gravity
A new question.
Why are the speeds of light and gravity equal? I assume it must be some fundamental feature of the Universe that sets that constant. Is it because the gravitational field of the Universe and spacetime are the same thing? Is this a stupid question?

What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


This message is a reply to:
 Message 54 by Son Goku, posted 02-28-2022 3:57 PM Son Goku has replied

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xongsmith
Member
Posts: 2578
From: massachusetts US
Joined: 01-01-2009
Member Rating: 6.8


Message 56 of 61 (892355)
03-06-2022 12:25 AM
Reply to: Message 55 by Tanypteryx
03-05-2022 9:30 PM


Re: Speed of Light = Speed of Gravity
i would guess that the elasticity of space rules both speeds and that they are bound to the same snapping back.
but i can be easily shown that that is false. i toss it out there with no emotional attachment.
shrug

"I'm the Grim Reaper now, Mitch. Step aside."

- xongsmith, 5.7d


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AZPaul3
Member
Posts: 8513
From: Phoenix
Joined: 11-06-2006
Member Rating: 5.3


Message 57 of 61 (892358)
03-06-2022 4:15 AM
Reply to: Message 55 by Tanypteryx
03-05-2022 9:30 PM


Re: Speed of Light = Speed of Gravity
What do they say? It’s only a stupid question if you don’t ask?
Is gravity a quantum field? Or is it a fold in the geometry of spacetime? Both? Manifestations of the same thing? What is the fabric of spacetime? Might it be the graviton field?
Don’t quote me but I recall the tale of a king, knocked from his steed in battle, stood and cried, “Quantum gravity! Quantum gravity! My kingdom for quantum gravity!” I may be a bit off on that but in essence I think this was the sentiment.
Edited by AZPaul3, : No reason given.

Eschew obfuscation. Habituate elucidation.

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Son Goku
Inactive Member


(2)
Message 58 of 61 (892365)
03-06-2022 12:00 PM
Reply to: Message 55 by Tanypteryx
03-05-2022 9:30 PM


Re: Speed of Light = Speed of Gravity
If this doesn't make sense just say so and I'll phrase it differently.
We humans can easily imagine an object travelling from Earth to Mars faster than light say, because we picture space and time as seperated intuitively. We just imagine space as a thing that exists independent of time, i.e. there is the expanse between Earth and Mars that exists regardless of what time passes. Modern Physics* says this isn't true.
In modern physics the universe has a four dimensional shape that has "gaps" in it. If an ant wants to walk from one side of a doughnut to another it can't take a straight path simply because there is a hole in the middle of the doughnut, it has to go the long way round. Similarly you can't go from Earth to Mars FTL because that path passes over a giant "hole" in the universe's geometry and you have to take the "long way round", namely slower than light.
Moving at the speed of light is essentially taking a path that skims right along the edges of these gaps, so it is impossible to move faster than this. Only if you are massless can you do this, which both light and gravity are.
*I say Modern Physics rather than Relativity since I am taking the more complete picture from Quantum Field Theory.

This message is a reply to:
 Message 55 by Tanypteryx, posted 03-05-2022 9:30 PM Tanypteryx has replied

Replies to this message:
 Message 59 by Tanypteryx, posted 03-06-2022 1:46 PM Son Goku has replied

  
Tanypteryx
Member
Posts: 4344
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 5.9


Message 59 of 61 (892373)
03-06-2022 1:46 PM
Reply to: Message 58 by Son Goku
03-06-2022 12:00 PM


Re: Speed of Light = Speed of Gravity
Moving at the speed of light is essentially taking a path that skims right along the edges of these gaps, so it is impossible to move faster than this. Only if you are massless can you do this, which both light and gravity are.
OK, I think this makes sense...but why do they both travel at the same speed? Is it somehow the limit itself that sets the speed? Something about spacetime makes them both travel at the maximum possible speed, just because they are massless?
In modern physics the universe has a four dimensional shape that has "gaps" in it.
OK, what are the "gaps"?
Particles have mass so they cannot travel at the speed of light, but some of them can be accelerated to "almost" the speed of light with magnetic fields. So protons are just sitting there, not moving unless they are accelerated, but neutrinos seem to be always in motion at almost the speed of light. What gives them that speed or what accelerated them? *
*I know these are different questions but I wanted to get them asked before I forget.

What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


This message is a reply to:
 Message 58 by Son Goku, posted 03-06-2022 12:00 PM Son Goku has replied

Replies to this message:
 Message 60 by Son Goku, posted 03-06-2022 3:18 PM Tanypteryx has replied

  
Son Goku
Inactive Member


(3)
Message 60 of 61 (892391)
03-06-2022 3:18 PM
Reply to: Message 59 by Tanypteryx
03-06-2022 1:46 PM


Re: Speed of Light = Speed of Gravity
OK, what are the "gaps"?
Holes as such in the shape of the universe. Like the hole in the center of a doughnut.
EDIT: A bit more detail. If you draw a 2D graph with time on the vertical axis and space on the horizontal axis then moving FTL at a constant speed is a line less then 45 degrees from the horizontal, i.e. covers more space than time. Although you can draw such paths modern physics says they don't really exist due to the universe's real geometry being different from this simple model. An FTL path is really like imagining a path along the surface of the Earth shorter than a great circle, i.e. invalid due to the true geometry.
So protons are just sitting there, not moving unless they are accelerated, but neutrinos seem to be always in motion at almost the speed of light. What gives them that speed or what accelerated them?
Neutrinos are usually given large kinetic energy at the moment of emission during a decay event.
Note that neutrinos are a bit more complicated than you'd think in that they either have a well-defined mass or a well-defined type (electron neutrino, muon neutrino, tau neutrino) but never both at the same time. So if you measure their type the result, which is probabilistic not determined, might be an electron neutrino but their mass remains undefined. If you measure their mass in some way (also probabilistic) their type is undefined.
but why do they both travel at the same speed?
Because they are both massless. Everything massless moves right along the "edge" of these gaps/shortest paths in spacetime. Since it's the shortest path through spacetime there's no quicker way to move than that. Humans can imagine shorter paths, i.e. FTL ones, because we don't correctly intuit the actual shape of the universe. It's like how there is no shorter way to move along the surface of the Earth than going along a great circle.
Edited by Son Goku, : More detail

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