Uncertainty principle

[dreich]

How does the uncertainty principle work?

[incitatus]

The uncertainty principle states that it is impossible to know the location and energy of a particle simultaneously beyond certain rigid tolerances. That is if you know precisely where it is then you must be vague about the energy, and if you know its energy you can only know roughly where it is. This is a consequence of observer participation, and is a fundamental, not an experimental glitch. Thats to say theres nothing wrong with the measuring equipment, its kjust the universe is a bit fuzzy.

[babthrower]

Good answer, Incitatus. The law arose in Physics, because to detect the presence of a particle you have to introduce a separate particle and so while their collision may reveal the position of the original particle, it will affect its speed, and so to detect its speed will not be possible because it has been affected by the experiment. Similarly to detect its speed first is possible, but the test affects its position. So you cannot detect both its speed and position in one experiment. This led to two different conclusions about whether the particle can be said to exist. One (Neils Bohr) was that it is meaningless to speak of the particle until it is measured: it doesn't exist. The other is that the particle exists, but its speed and position are undetermined. Bohr's definition prevailed, but the question is still open. An interesting sidelight is in Social Sciences. Some scientists claim that all research on a subject (either an individual or a culture) is invalid (from a strict scientific point of view) because the researcher always and inevitably affects the subject during the research.

[bimsey]

i am not sure

[JohnPPotts]

Has also given rise to the physicists joke - "Damn! I know the exact speed my keys are travelling at!" - ie. I don't know where they are. You've got to get your laughs where you can as a scientist, I guess!

[cooj2]

Sign on a lavatory door.....Please knock Heisenberg may be in here!

[kalpesh]

the uncertainity of this answer itself a hint for the correct answer.Think abt it.

[kalpesh]

the answer will either protect or shatter our views of objective reality