“Maybe, but they’re still both false! What exactly is the distinction you have in mind?”
Yes, and me and the Pacific Ocean are both more than 50% water by mass. Newtonian gravitation successfully explained a huge number of phenomena. Phlogiston did not.
“Anyway, I had just meant LET versus SR, but what exactly is the experimental evidence against an aether?”
With quantum mechanics (and modern experimental technology), we can actually look down below the level of individual particles, and we have found that photons are actually their own particles, not patterns of vibration (or whatever) within other particles.
“This would be a lot more convincing if the most recent and most successful theory of physics weren’t such a glaring counter-example.”
“I disagree. Even under the naive theory of truth that is popular here”
Would you care to propose some alternative theory of truth?
“While that is still an open question people might come to different conclusions about which way is most promising.”
Obviously, but that disagreement should then be resolved by reference to experiment. There is no room for persistent disagreement. In engineering, you can have five different methods, each with their own advantages and disadvantages, and this is a stable state. In science, having five different theories is not a stable state; it needs to be resolved, rather than harden into different factions.
“And then once you notice that theories of physics have this nasty habit of turning out false… well then I don’t even know what you’re using to declare A right and B wrong.”
Experimental evidence?
“it then makes a lot of sense to think about the benefits working under different sets of theoretical assumptions (i.e. approaches).”
What does that even mean? How would you apply that to a theory of physics (past or present)? What “theoretical assumptions” are involved in, say, Special Relativity? Special Relativity makes the assertion that the speed of light is constant regardless of reference frame, but this isn’t just a mathematical axiom that you can pick up and discard at will; it is based on a huge pile of experimental evidence.
With quantum mechanics (and modern experimental technology), we can actually look down below the level of individual particles, and we have found that photons are actually their own particles, not patterns of vibration (or whatever) within other particles.
We knew this before quantum mechanics. Lorentz’s aether wasn’t matter.
I’ve read (indeed, I own) this book. I don’t know how to evaluate elegance, but the Standard Model particle zoo isn’t simple, at least not in the way Newton or special relativity is simple. I wish you would assume I have some idea what I’m talking about and that my concerns and questions might be well motivated, however alien they seem to you.
Would you care to propose some alternative theory of truth?
I would like too but I haven’t really figured out what I think. I’m not particularly radical, but I think the epistemology Eliezer has laid out on Less Wrong has some holes, leaves important questions unanswered etc. Maybe one day I’ll write something.
Obviously, but that disagreement should then be resolved by reference to experiment. There is no room for persistent disagreement. In engineering, you can have five different methods, each with their own advantages and disadvantages, and this is a stable state. In science, having five different theories is not a stable state; it needs to be resolved, rather than harden into different factions.
But they aren’t always resolved that way! Special relativity beat out Lorentzian Ether Theory even though they are empirically equivalent. Obviously if you have two theories that predict different outcomes of some feasible experiment you can run that experiment and resolve the difference. The question is, what we do when there is no experiment to run? Well we do some math and try to come up with testable hypotheses. Using different theories or different vocabulary seems to affect how easy it is to do the math and generate hypotheses.
“And then once you notice that theories of physics have this nasty habit of turning out false… well then I don’t even know what you’re using to declare A right and B wrong.”
Experimental evidence?
As the sentence immediately following this one was supposed to indicate, usually both theories are wrong in the long run.
What does that even mean? How would you apply that to a theory of physics (past or present)? What “theoretical assumptions” are involved in, say, Special Relativity? Special Relativity makes the assertion that the speed of light is constant regardless of reference frame, but this isn’t just a mathematical axiom that you can pick up and discard at will; it is based on a huge pile of experimental evidence.
It isn’t based on any experimental evidence that distinguishes it from a theory that says mass contracts in the direction it moves in. But it turns out that if you start from a theory which says’s light’s speed is constant you can come up with things like the theory of General Relativity. Alternately, you might have two theories that describe totally different phenomena without error but have the potential to describe things about other phenomena and eventually one might be subsumed under the other. But it won’t always be obvious which theory is the more fundamental one. I suspect one reason there is a lot of work done trying to incorporate gravity into quantum mechanics rather than the other three fundamental forces into General Relativity is that SR/GR just doesn’t have the vocabulary to make hypotheses about particle physics. The former is sort of obvious though “Oh there is another force, there must be this other wavicle: a graviton.” That doesn’t mean it will be an successful approach but that is part of the reason it is the popular one.
Special relativity beat out Lorentzian Ether Theory even though they are empirically equivalent. Obviously if you have two theories that predict different outcomes of some feasible experiment you can run that experiment and resolve the difference.
These two theories are not equivalent at all; they predict different outcomes for the Michelson-Morley experiment, unless you patch up the ether by requiring it to be at rest relative to the Earth at all times.
Would the person or persons down voting my comments here mind at least explaining this one? Afaict I’m just correcting someone on a factual error and providing a citation. If wikipedia is wrong on this matter I’d like to know.
The problem with that solution is that you end up with a theory that makes the same predictions as SR, but contains an extra concept that plays no role in making predictions: a distinguished but unobservable reference frame of absolute rest, with respect to which all the other reference frames involve time dilations and length contractions. When you cut off that useless spinning cog you are left with SR.
“Maybe, but they’re still both false! What exactly is the distinction you have in mind?”
Yes, and me and the Pacific Ocean are both more than 50% water by mass. Newtonian gravitation successfully explained a huge number of phenomena. Phlogiston did not.
“Anyway, I had just meant LET versus SR, but what exactly is the experimental evidence against an aether?”
With quantum mechanics (and modern experimental technology), we can actually look down below the level of individual particles, and we have found that photons are actually their own particles, not patterns of vibration (or whatever) within other particles.
“This would be a lot more convincing if the most recent and most successful theory of physics weren’t such a glaring counter-example.”
You mean quantum mechanics? Quantum mechanics is very elegant, it’s just usually explained badly. See http://www.amazon.com/QED-Strange-Theory-Light-Matter/dp/0691024170.
“I disagree. Even under the naive theory of truth that is popular here”
Would you care to propose some alternative theory of truth?
“While that is still an open question people might come to different conclusions about which way is most promising.”
Obviously, but that disagreement should then be resolved by reference to experiment. There is no room for persistent disagreement. In engineering, you can have five different methods, each with their own advantages and disadvantages, and this is a stable state. In science, having five different theories is not a stable state; it needs to be resolved, rather than harden into different factions.
“And then once you notice that theories of physics have this nasty habit of turning out false… well then I don’t even know what you’re using to declare A right and B wrong.”
Experimental evidence?
“it then makes a lot of sense to think about the benefits working under different sets of theoretical assumptions (i.e. approaches).”
What does that even mean? How would you apply that to a theory of physics (past or present)? What “theoretical assumptions” are involved in, say, Special Relativity? Special Relativity makes the assertion that the speed of light is constant regardless of reference frame, but this isn’t just a mathematical axiom that you can pick up and discard at will; it is based on a huge pile of experimental evidence.
I wouldn’t be so sure. (http://www.jimloy.com/physics/phlogstn.htm) But it certainly had other problems.
We knew this before quantum mechanics. Lorentz’s aether wasn’t matter.
I’ve read (indeed, I own) this book. I don’t know how to evaluate elegance, but the Standard Model particle zoo isn’t simple, at least not in the way Newton or special relativity is simple. I wish you would assume I have some idea what I’m talking about and that my concerns and questions might be well motivated, however alien they seem to you.
I would like too but I haven’t really figured out what I think. I’m not particularly radical, but I think the epistemology Eliezer has laid out on Less Wrong has some holes, leaves important questions unanswered etc. Maybe one day I’ll write something.
But they aren’t always resolved that way! Special relativity beat out Lorentzian Ether Theory even though they are empirically equivalent. Obviously if you have two theories that predict different outcomes of some feasible experiment you can run that experiment and resolve the difference. The question is, what we do when there is no experiment to run? Well we do some math and try to come up with testable hypotheses. Using different theories or different vocabulary seems to affect how easy it is to do the math and generate hypotheses.
As the sentence immediately following this one was supposed to indicate, usually both theories are wrong in the long run.
It isn’t based on any experimental evidence that distinguishes it from a theory that says mass contracts in the direction it moves in. But it turns out that if you start from a theory which says’s light’s speed is constant you can come up with things like the theory of General Relativity. Alternately, you might have two theories that describe totally different phenomena without error but have the potential to describe things about other phenomena and eventually one might be subsumed under the other. But it won’t always be obvious which theory is the more fundamental one. I suspect one reason there is a lot of work done trying to incorporate gravity into quantum mechanics rather than the other three fundamental forces into General Relativity is that SR/GR just doesn’t have the vocabulary to make hypotheses about particle physics. The former is sort of obvious though “Oh there is another force, there must be this other wavicle: a graviton.” That doesn’t mean it will be an successful approach but that is part of the reason it is the popular one.
These two theories are not equivalent at all; they predict different outcomes for the Michelson-Morley experiment, unless you patch up the ether by requiring it to be at rest relative to the Earth at all times.
Could you be missing the “Lorentzian” there?
What FAWS said. The problem is solved with length contraction.
Would the person or persons down voting my comments here mind at least explaining this one? Afaict I’m just correcting someone on a factual error and providing a citation. If wikipedia is wrong on this matter I’d like to know.
The problem with that solution is that you end up with a theory that makes the same predictions as SR, but contains an extra concept that plays no role in making predictions: a distinguished but unobservable reference frame of absolute rest, with respect to which all the other reference frames involve time dilations and length contractions. When you cut off that useless spinning cog you are left with SR.