Tim Tyler: According to Hedweb, most “leading cosmologists and other quantum field theorists” thought that the “Many-Worlds Interpretation was correct 10 years ago.
Ah, but did they have to depart from the scientific method in order to believe it? The question isn’t what scientists believe; scientists don’t always follow the scientific method. The physicists who embrace MWI are acting rationally; the physicists who reject it are acting scientifically—that’s the theme of this post.
Manon: I don’t believe you.
Then you certainly understood me. This is another comment that makes me want to cheer, because it means you really got it.
This is the only explaination of QM I’ve been able to understand—I would have a hard time checking.
Go back and look at other explanations of QM and see if they make sense now. Check a textbook. Alternatively, check Feynman’s QED. Find a physicist you trust, ask them if I got it wrong, if I did post a comment. Bear in mind that a lot of physicists do believe MWI.
I myself am mostly relying on the fact that neither Scott Aaronson nor Robin Hanson nor any of several thousand readers have said anything like “Wrong physics” or “Well, that’s sort of right, but wrong in the details...”
(what is an amplitude exactly?)
It’s always treated as a complex number with a real and imaginary part, though I prefer Feynman’s calling it a “little arrow”, since that makes it clear there’s no preferred direction of the little arrows.
then the idea of a single world is preposterous, and I really need to work out the implications.
The most important implication is that the scientific method can break down. There are some minor ethical implications of many-worlds itself (e.g., average utilitarianism suddenly becomes a lot more appealing) but mostly, it all adds up to normality.
Maybe it’s because I was hung-over during most of my undergrad math lectures, but one of the things I”m having trouble coming to terms with is the fact that imaginary (rather, complex)numbers turn out to be so real. I can deal with the idea of amplitude have two dimensions and rotating through them, and with amplitudes canceling each other out because of this, but it’s not clear to me, if there is “no preferred direction” for amplitudes, why the square root of minus one is involved.
Are there other mathematical formulations possible? Or a good source for this that could re-align my intuitions with reality?
I can deal with the idea of amplitude have two dimensions and rotating through them, and with amplitudes canceling each other out because of this, but it’s not clear to me, if there is “no preferred direction” for amplitudes, why the square root of minus one is involved. Are there other mathematical formulations possible?
Matrices of the form ((a, -b), (b, a))---that is, compositions of a scaling and a rotation in the plane—are isomorphic to complex numbers, which makes sense because when we multiply complex numbers in polar form, we multiply their magnitudes and add their arguments.
Tim Tyler: According to Hedweb, most “leading cosmologists and other quantum field theorists” thought that the “Many-Worlds Interpretation was correct 10 years ago.
Ah, but did they have to depart from the scientific method in order to believe it? The question isn’t what scientists believe; scientists don’t always follow the scientific method. The physicists who embrace MWI are acting rationally; the physicists who reject it are acting scientifically—that’s the theme of this post.
Manon: I don’t believe you.
Then you certainly understood me. This is another comment that makes me want to cheer, because it means you really got it.
This is the only explaination of QM I’ve been able to understand—I would have a hard time checking.
Go back and look at other explanations of QM and see if they make sense now. Check a textbook. Alternatively, check Feynman’s QED. Find a physicist you trust, ask them if I got it wrong, if I did post a comment. Bear in mind that a lot of physicists do believe MWI.
I myself am mostly relying on the fact that neither Scott Aaronson nor Robin Hanson nor any of several thousand readers have said anything like “Wrong physics” or “Well, that’s sort of right, but wrong in the details...”
(what is an amplitude exactly?)
It’s always treated as a complex number with a real and imaginary part, though I prefer Feynman’s calling it a “little arrow”, since that makes it clear there’s no preferred direction of the little arrows.
then the idea of a single world is preposterous, and I really need to work out the implications.
The most important implication is that the scientific method can break down. There are some minor ethical implications of many-worlds itself (e.g., average utilitarianism suddenly becomes a lot more appealing) but mostly, it all adds up to normality.
Maybe it’s because I was hung-over during most of my undergrad math lectures, but one of the things I”m having trouble coming to terms with is the fact that imaginary (rather, complex)numbers turn out to be so real. I can deal with the idea of amplitude have two dimensions and rotating through them, and with amplitudes canceling each other out because of this, but it’s not clear to me, if there is “no preferred direction” for amplitudes, why the square root of minus one is involved.
Are there other mathematical formulations possible? Or a good source for this that could re-align my intuitions with reality?
Matrices of the form ((a, -b), (b, a))---that is, compositions of a scaling and a rotation in the plane—are isomorphic to complex numbers, which makes sense because when we multiply complex numbers in polar form, we multiply their magnitudes and add their arguments.