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WaveJumper
2009-Nov-01, 02:23 PM
Quantum mechanics defines physical size as the probability distribution of finding a particle over a small area of space. While electrons and quarks are considered fundamental and do not have physical dimensions by themselves, when the probability distribution is mapped out over a specific area, we get the familiar notion of physical size(keeping in mind that quantum objects do not have well defined boundaries).
Now, if i were able(at least theoretically) to snap a picture of my Civic in exactly one Planck time unit -- 10^-43sec, quantum mechanics predicts that the picture will not contain anything physical(disregrading for this thought experiment the speed of light). While it's relatively certain that the picture will not contain the Civic the camera was pointed at, my question is what 'pattern'(if any) would at least theoretically emerge in the picture taken?

My opinion would be total blackness, since there are no superpositional electrons to reflect light waves back onto the camera lens.

Ken G
2009-Nov-01, 03:53 PM
Actually, I think if you put all the light you are observing together, you'd get a picture of your car all right-- but it would be a car that doesn't exist any more!

gzhpcu
2009-Nov-01, 04:22 PM
I thought our physics broke down at the Planck time...:confused: So that no prediction would be possible...

Ken G
2009-Nov-01, 09:13 PM
My interpretation of the OP was to choose that scale as the deepest scale we could penetrate before physics as we know it broke down completely. You might have to back off from that point a bit to avoid having your photons creating black holes instead of acting like photons, and so forth. My point is only that what it means to be a car doesn't change as you increase the energy of the light you are using to look at a car, but the effect it has on the car certainly does.

Ivan Viehoff
2009-Nov-03, 02:18 PM
Now, if i were able(at least theoretically) to snap a picture of my Civic in exactly one Planck time unit -- 10^-43sec, quantum mechanics predicts that the picture will not contain anything physical(disregrading for this thought experiment the speed of light).
Can you "disregard" the speed of light for this? Planck time is proportional to c^(-5/2). If you "disregard" the speed of light, ie assume that the speed of light is something else, then 1E-43s ceases to be the Planck time.