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Roger Penrose Says Physics Is Wrong, From String Theory to Quantum Mechanics

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Re: Roger Penrose Says Physics Is Wrong, From String Theory to Quantum Mechanics

#21

Post by jessriedel »

snowwrestler wrote: post #17

Of course it's wrong; all scientific theories are provisional approximations, and the conflicts between quantum mechanics and general relativity are well known. The hard part is proposing an alternative theory that fits all the known evidence. Quantum mechanics and general relativity both match a ton of observations; anything that is going to replace them will need to at least match the same set of evidence at least…

Roger Penrose believes quantum mechanics will fail long before it conflicts with general relativity, which is a bold claim. In addition, the conflict between general relativity and quantum mechanics is popularly overstated. My understanding is that no one knows yet whether the non-renormalizability of gravity in QFT near the Planck scale is necessarily a sign that the theory breaks, rather than just a problem with perturbation theory. It's conceivable that non-perturbative effects will save the day.

Re: Roger Penrose Says Physics Is Wrong, From String Theory to Quantum Mechanics

#22

Post by planetguy »

Whodi wrote: post #20

"Is it true that you were bad at math as a kid?" "I was unbelievably slow... I always got lost... I was at least twice as slow as anybody else. Eventually I would do very well. You see, if I could do it that way, I would get very high marks." Speaking as someone who still struggles with math, and was generally the dumbest kid in the most advanced classes, it's a huge relief to hear that someone as brilliant as Penros…

I don't know how old you are, but I'm pretty sure Penrose overtook you by the time he was your age.

Re: Roger Penrose Says Physics Is Wrong, From String Theory to Quantum Mechanics

#23

Post by jessriedel »

ktizo wrote: post #10
Flow wrote: post #5

Earlier quoted context omitted.

Are any of his book suitable as casual on-the-tram reading? Could you recommend one of his books? Thanks.

All books are suitable for casually reading on trams, apart from really old and delicate or oversized ones. I loved 'The Emperors's New Mind' and 'Shadows of the Mind', and did read some of those two while on train journeys, if that helps at all.

The Road to Reality, while certainly not a technical work in the traditional sense, is not light reading.

Re: Roger Penrose Says Physics Is Wrong, From String Theory to Quantum Mechanics

#24

Post by nollidge »

diminish wrote: post #15
aidenn0 wrote: post #14

Of course by this definition of wrong, Newtonian mechanics is wrong, which didn't stop me from taking a 400 level course on it.

Roger Penrose has fundamental thoughts about the physics and AI, not simply callling them wrong wrong in the sense of falsifibility..Read his books.

I don't think the aidenn0 is talking about falsifiability, but accuracy. As in, Newtonian mechanics is not 100% accurate, but it works well enough for macro-level calculations.

Like Asimov said, "when people thought the earth was flat, they were wrong. When people thought the earth was spherical, they were wrong. But if you think that thinking the earth is spherical is just as wrong as thinking the earth is flat, then your view is wronger than both of them put together." - http://chem.tufts.edu/AnswersInScience/RelativityofWrong.htm

Re: Roger Penrose Says Physics Is Wrong, From String Theory to Quantum Mechanics

#25

Post by jessriedel »

ceejayoz wrote: post #19
stefantalpalaru wrote: post #16

Earlier quoted context omitted.

You might want to start by looking up the way sperm is being produced. It will help you clear the confusion with the link between the mother's age and birth defects.

Age of the father does have an effect, actually. http://www.webmd.com/infertility-and-reproduction/news/20030... edit: Also, as someone who's had to use sperm donation to conceive... > Wonder if that's his kid? is pretty offensive. It's his kid, whether he's the genetic father or not.

It certainly does, especially for genetic (rather than developmental) defects. Wikipedia has a good summary

http://en.wikipedia.org/wiki/Paternal_age_effect

Still, the mother's age is a lot more important, all things considered.

Re: Roger Penrose Says Physics Is Wrong, From String Theory to Quantum Mechanics

#26

Post by Whodi »

planetguy wrote: post #22
Whodi wrote: post #20

"Is it true that you were bad at math as a kid?" "I was unbelievably slow... I always got lost... I was at least twice as slow as anybody else. Eventually I would do very well. You see, if I could do it that way, I would get very high marks." Speaking as someone who still struggles with math, and was generally the dumbest kid in the most advanced classes, it's a huge relief to hear that someone as brilliant as Penros…

I don't know how old you are, but I'm pretty sure Penrose overtook you by the time he was your age.

Haha, that's an understatement, I'm sure he was light years ahead of me as early as 10. It's just inspiring to know that one can struggle with some of the basics and rebound to do great things.

Re: Roger Penrose Says Physics Is Wrong, From String Theory to Quantum Mechanics

#27

Post by te_platt »

Flow wrote: post #5
drallison wrote: post #2

Not much content in this article. Read his books to get a feeling for the breadth and depth of his thought.

Are any of his book suitable as casual on-the-tram reading? Could you recommend one of his books? Thanks.

I wouldn't say any of his books are exactly casual reading. The Large the Small and the Human Mind is probably the most casual in that it merely requires thinking and even then some of that is done for you the responses from Abner Shimony, Nancy Cartwright, and Stephen Hawking (contributing authors). The others require active engagement to work through. Especially Road to Reality - there is nothing casual about that one.

Re: Roger Penrose Says Physics Is Wrong, From String Theory to Quantum Mechanics

#28

Post by planetguy »

snowwrestler wrote: post #17

Of course it's wrong; all scientific theories are provisional approximations, and the conflicts between quantum mechanics and general relativity are well known. The hard part is proposing an alternative theory that fits all the known evidence. Quantum mechanics and general relativity both match a ton of observations; anything that is going to replace them will need to at least match the same set of evidence at least…

You seem to be engaging more with the headline writer than with Penrose. They're both, perhaps, wrong, but Penrose is wrong in a far more interesting way.

Penrose doesn't just think quantum mechanics is wrong in the sense that it can't quite be lined up with general relativity, he thinks that quantum mechanics and consciousness are the same problem and that we can't understand one without the other. Now, to me this smacks a bit of the old argument:

1. I don't understand baseball

2. I don't understand women

3. Therefore, women and baseball must be related somehow

but he has slightly better reasons than that for believing what he does.

Consciousness and quantum mechanics are both fascinating problems to understand; personally I don't think they're the same problem but I don't mind if some smart folks want to think carefully about the possibility that they are.

If consciousness is a property of quantum mechanics then this ought to be at least partially measurable. All you have to do is to construct an intelligent non-quantum computer and ask it "Hey, are you conscious?" Of course this doesn't really help you, because what if the computer just thinks it's conscious but doesn't have real consciousness the way we do? What would this even mean? What is it like to be an intelligent but non-conscious mind? In my own opinion the question is meaningless which is why I think consciousness is some kind of inevitable emergent property of intelligent systems; but of course there's thousands of philosophers out there tackling this very question so I won't pretend to have any original thoughts on it.

Re: Roger Penrose Says Physics Is Wrong, From String Theory to Quantum Mechanics

#30

Post by natep »

nollidge wrote: post #24
diminish wrote: post #15

Earlier quoted context omitted.

Roger Penrose has fundamental thoughts about the physics and AI, not simply callling them wrong wrong in the sense of falsifibility..Read his books.

I don't think the aidenn0 is talking about falsifiability, but accuracy. As in, Newtonian mechanics is not 100% accurate, but it works well enough for macro-level calculations. Like Asimov said, "when people thought the earth was flat, they were wrong. When people thought the earth was spherical, they were wrong. But if you think that thinking the earth is spherical is just as wrong as thinking the earth is flat, the…

That is what aidenn0 seems to be talking about, but that's not what Penrose is talking about. Penrose is very clear that the predictions of QM are extremely accurate. His contention is that the implications of QM cannot be true (that there must be parallel worlds or "it doesn't matter what's really happening in a superposition of states, just that the predictions are accurate"), therefore QM as it is today cannot be a part of any single unified theory.
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