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Sep 28, 2017 at 18:48 history edited AccidentalFourierTransform CC BY-SA 3.0
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Jun 4, 2017 at 9:54 comment added Physics Footnotes @Luke Thanks very much; I've now tracked it down. Tim Maudlin is one of my favorite authors on foundational matters in QM, so I don't like to miss out on anything he's written :-)
Jun 3, 2017 at 9:47 comment added Luke @PhysicsFootnotes: Tim Maudlin. Space-Time in the Quantum World. In James T. Cushing, Arthur Fine, and Sheldon Goldstein, editors, Bohmian Mechanics and Quantum Theory:An Appraisal, pages 285–307. Kluwer Academic Press, 1996.
Jun 3, 2017 at 0:08 comment added Physics Footnotes @Luke Do you have a full reference for that Maudlin paper you refer to? I can't seem to track down a paper of his with that title. Thanks.
May 26, 2017 at 9:10 history edited JDługosz CC BY-SA 3.0
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May 24, 2017 at 13:21 comment added alex @Luke But does just making the formula look the same when the x and t terms in it are tranformed in a certain way guarantee that the rest of the significant features of SR (like the constancy of the speed of photon wavepackets which Alfred seems to me to be implying )will also be inherited?
May 24, 2017 at 12:44 comment added Selena Ballerina @alex ..... When you measure an electron's position (that in itself is a little bit of a complicated notion for the Dirac equation, but the problems are not really relevant here - let's just assume that there is some calculation you can do from the equation's solution to come up with a probability amplitude for position), the result will give you a statistical spread of co-ordinates for possible answers.
May 24, 2017 at 12:40 comment added Selena Ballerina @alex In QM only measurements have the statistical distributions, the "uncertainties" and all the things that are (validly) bothering you. AS you point out, this makes notions of measured spacetime co-ordinates problematic. But what Luke is saying is that the underlying theory that lets you calculate these statistical distributions can be Lorentz-invariant. Things like the Dirac equation describes the probability amplitude (or a vector-like quantity whence one calculates the PA) as a function of the spacetime co-ordinates. The PA is not measured, and nor are the co-ordinates ....
May 24, 2017 at 12:37 comment added Luke Lorentz invariance is lorentz invariance, if classical or quantum does not matter. This is a property of a physical law - the physical law contains space and time coordinates, and the Lorentz invariance then says: If I transform to another Lorentz frame, the physical law takes the same form. This is true for the Dirac equation, and false for the Schrödinger equation.
May 24, 2017 at 12:32 comment added alex classically lorentz invariance constitutes the invariamce of proper time i.e. the "distance" through spacetime between two events that occur at specific points in space at specific times from each observers point of view. what does Lorentz invariance mean in qm? what does proper time measure the "distance" between?
May 24, 2017 at 12:17 history answered Luke CC BY-SA 3.0