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Lost Causes of Theoretical Physics (2003)

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Re: Lost Causes of Theoretical Physics (2003)

#41

Post by posterboy »

akvadrako wrote: post #39
dandare wrote: post #38

Does it say Mach Principle is incorrect? That is good, as a non physicist I could never wrap my head around the distant stars influencing anything.

The distant stars are important because they make space flat. Remember that general relativity says mass bends space, or more accurately is the same thing as space. So if all the mass was nearby, space would bend inward around the current point and it would fold in on itself - the universe would be like the inside of a sphere. Because the mass is distributed evenly at the largest scales, it instead continues flatly i…

> the universe would be like the inside of a sphere.

The surface of which is "flat"? The interior surface, if that's the right word. Like living on the Event Horizon of a black hole. So we don't and hardly can know what's outside or inside or on the outside or inside.

Re: Lost Causes of Theoretical Physics (2003)

#42

Post by John_KZ »

hliyan wrote: post #32

Not a physicist, but isn't "Bohmian Mechanics" (1) what's also known as "Pilot Wave Theory", which is now gaining experimental support (2) ? Clarke's First Law: "When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong." 1. https://en.wikipedia.org/wiki/De_Broglie–Bohm_theory 2. https://www.quanta…

Yes it is. The author presents his dogma as the one and only truth, which you're not allowed to deny if you want to be a "scientist". It's similar to labelling people as climate change "deniers" and "anti-vaxxers" etc etc.

Re: Lost Causes of Theoretical Physics (2003)

#43

Post by John_KZ »

whatshisface wrote: post #33
hliyan wrote: post #32

Not a physicist, but isn't "Bohmian Mechanics" (1) what's also known as "Pilot Wave Theory", which is now gaining experimental support (2) ? Clarke's First Law: "When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong." 1. https://en.wikipedia.org/wiki/De_Broglie–Bohm_theory 2. https://www.quanta…

Pilot waves, multiverse and Copenhagen are fundamentally ineligible for experimental support, at least with respect to each other. They lead to the same numbers, meaning than an experiment that agrees with one will also agree with the others. It's something like trying to tell the difference between 2x=2y and x+2=y+2. The "support" in the article is really just a physical system that obeys (as a macroscopic approxima…

While the current formulation details of the pilot wave theory doesn't allow for new predictions, a better formulated one will. I strongly believe we'll see the breakthrough in the coming 10-15 years. Quantum mechanics are statistic predictions and it's about time we treat them as such.

Re: Lost Causes of Theoretical Physics (2003)

#44

Post by andrepd »

John_KZ wrote: post #42
hliyan wrote: post #32

Not a physicist, but isn't "Bohmian Mechanics" (1) what's also known as "Pilot Wave Theory", which is now gaining experimental support (2) ? Clarke's First Law: "When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong." 1. https://en.wikipedia.org/wiki/De_Broglie–Bohm_theory 2. https://www.quanta…

Yes it is. The author presents his dogma as the one and only truth, which you're not allowed to deny if you want to be a "scientist". It's similar to labelling people as climate change "deniers" and "anti-vaxxers" etc etc.

That's ridiculous. It's on you to provide evidence for your position. Absent that, it's free for other scientists to criticise you on that ground.

Re: Lost Causes of Theoretical Physics (2003)

#45

Post by John_KZ »

andrepd wrote: post #44
John_KZ wrote: post #42

Earlier quoted context omitted.

Yes it is. The author presents his dogma as the one and only truth, which you're not allowed to deny if you want to be a "scientist". It's similar to labelling people as climate change "deniers" and "anti-vaxxers" etc etc.

That's ridiculous. It's on you to provide evidence for your position. Absent that, it's free for other scientists to criticise you on that ground.

I'm sorry you're blind.

Re: Lost Causes of Theoretical Physics (2003)

#46

Post by JohnStrangeII »

John_KZ wrote: post #45
andrepd wrote: post #44

Earlier quoted context omitted.

That's ridiculous. It's on you to provide evidence for your position. Absent that, it's free for other scientists to criticise you on that ground.

I'm sorry you're blind.

What a strange comment, given that he's obviously right. You're not a scientist, are you?

Re: Lost Causes of Theoretical Physics (2003)

#47

Post by TheOtherHobbes »

zombieprocesses wrote: post #16
sgillen wrote: post #2

The many worlds interpretation is just that, and INTERPRETATION, not a predictive theory. The article seems really upset by that, but is it any reason to label it a lost cause? I guess you can’t really study it or preform experiments on it but that shouldn’t be any suprise for any interpretation of quantum mechanics. I might be missing something here...

If a theory isn't predictive, it isn't falsifiable. If it isn't falsifiable, then the theory isn't truly scientific. This is a major issue/concern in advanced theoretical physics. Is it really physics if you can't experiment or is it just mathematics? The foundation of science is falsiability within the scientific method. It's the core tenet.

But you need to do a lot of speculative work before falsifiability becomes possible. And that speculative work is going to involve groping around in the dark being guided by mathematical logic (and a certain amount of politics, fashion, and wishful thinking.)

Considering physics as if MWI could be true has the potential to lead to mathematical elaboration and eventual falsifiability.

Considering physics as if there's no need to interpret QM because there's nothing to interpret (because Copenhagen is the correct interpretation) is a statement of faith, not rigour - because as a position, it's no more falsifiable than MWI, or Bohm, or any of the other interpretations.

The point of mathematical physics is to generate new falsifiable predictions. It's still science, it's just embryonic proto-knowledge - which is why it's called research, not teaching.

Re: Lost Causes of Theoretical Physics (2003)

#48

Post by naasking »

John_KZ wrote: post #43
whatshisface wrote: post #33

Earlier quoted context omitted.

Pilot waves, multiverse and Copenhagen are fundamentally ineligible for experimental support, at least with respect to each other. They lead to the same numbers, meaning than an experiment that agrees with one will also agree with the others. It's something like trying to tell the difference between 2x=2y and x+2=y+2. The "support" in the article is really just a physical system that obeys (as a macroscopic approxima…

While the current formulation details of the pilot wave theory doesn't allow for new predictions, a better formulated one will. I strongly believe we'll see the breakthrough in the coming 10-15 years. Quantum mechanics are statistic predictions and it's about time we treat them as such.

> While the current formulation details of the pilot wave theory doesn't allow for new predictions

Actually pilot wave theories do have new predictions, namely quantum non-equilibrium. We just have no idea if we can actually design an experiment for it.

Re: Lost Causes of Theoretical Physics (2003)

#49

Post by naasking »

zombieprocesses wrote: post #16
sgillen wrote: post #2

The many worlds interpretation is just that, and INTERPRETATION, not a predictive theory. The article seems really upset by that, but is it any reason to label it a lost cause? I guess you can’t really study it or preform experiments on it but that shouldn’t be any suprise for any interpretation of quantum mechanics. I might be missing something here...

If a theory isn't predictive, it isn't falsifiable. If it isn't falsifiable, then the theory isn't truly scientific. This is a major issue/concern in advanced theoretical physics. Is it really physics if you can't experiment or is it just mathematics? The foundation of science is falsiability within the scientific method. It's the core tenet.

> If a theory isn't predictive, it isn't falsifiable. If it isn't falsifiable, then the theory isn't truly scientific.

That's an overly anemic view of science. Scientific theories have both predictive and explanatory power. Interpretations of QM don't change the former, but they do change the latter.

Copenhagen, favoured by this article's author for some unfathomable reason, has little explanatory power. Many worlds and Bohmian mechanics have excellent explanatory power, and their predictive power equals Copenhagen.

Re: Lost Causes of Theoretical Physics (2003)

#50

Post by naasking »

ajkjk wrote: post #3
sgillen wrote: post #2

The many worlds interpretation is just that, and INTERPRETATION, not a predictive theory. The article seems really upset by that, but is it any reason to label it a lost cause? I guess you can’t really study it or preform experiments on it but that shouldn’t be any suprise for any interpretation of quantum mechanics. I might be missing something here...

After skimming the whole thing, I was relieved to see that the argument against Many Worlds was the only one I considered invalid. It took the form of "It's not even a testable theory", rather than "it has mathematical deficiencies". Well, of course, no one's saying it's testable necessarily, but for various aesthetic and intuitive reasons it still seems valid. Just don't expect predictions from it and you'll be fine…

> After skimming the whole thing, I was relieved to see that the argument against Many Worlds was the only one I considered invalid.

You should consider the Bohmian criticisms invalid as well then. Many have argued that de Broglie-Bohm is "many worlds in disguise", so if the criticisms the author levels against Bohmian mechanics are true, then they apply to MWI, but if they don't apply to MWI, then they don't apply to Bohmian mechanics either.

Not because they are the same theory, because they are not ontologically the same, but the formalisms are interchangeable.

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