Why have so many physicists shrugged off the paradoxes of quantum mechanics?

Post by l33tman » Sat, Apr 20, 2019, 9:24 AM UTC

Sylos wrote: post #35

gus_massa wrote: post #2

> Bohr postulated a distinction between the quantum world and the world of everyday objects. A “classical” object is an object of everyday experience. It has, for example, a definite position and momentum, whether observed or not. A “quantum” object, such as an electron, has a different status; it’s an abstraction. Some properties, such as electrical charge, belong to the electron abstraction intrinsically, but other…

> This is a common error. Macroscopic "everyday" objects don't have a definite position and momentum. Macroscopic objects are quantum objects. But when the mass is big enough, the position and momentum can be defined simultaneously with an error that is so small that you can just ignore the uncertainty and approximate them as classical objects. To put this into simpler terms: Whenever we measure something, we need to…

Post by akvadrako » Sat, Apr 20, 2019, 9:29 AM UTC

PaulHoule wrote: post #5

They aren't paradoxes of quantum mechanics. They are a paradox between how we intuitively expect the world to work and reality. Our intuition is wrong.

Post by dghf » Sat, Apr 20, 2019, 9:33 AM UTC

TheOtherHobbes wrote: post #40

firethief wrote: post #32

Earlier quoted context omitted.

MWI is what happens when you don't require the existence of anything extra (collapse phenomenon). It's like how isn't an unexplained phenomenon--it results from the evolution of the observer's perspective. In MWI there is no event corresponding to collapse for the same reason that Gallileo's model doesn't have any correlate of epicycles.

In MWI the event corresponding to collapse is the supposed appearance of an entire universe, which is - conveniently - impossible to detect. And which "explains" any one timeline of experience as "Actually, that's still just random." So MWI goes from "That's random and we don't know why" to "That's random, we don't know why, but now we've added a universe too, although we can't prove it exists." Something about this…

Post by pdkl95 » Sat, Apr 20, 2019, 9:42 AM UTC

atomack wrote: post #68

gus_massa wrote: post #66

Earlier quoted context omitted.

I agree with both. This explanation is easier to understand, but it makes it look like a technological problem that can be solved, instead of a fundamental property of the universe.

I think david927's intuition is more correct here. The uncertainty in the position and momentum is intrinsic to quantum mechanics - it's built into the 'wave function'. The suggestion that if one pushes away something by throwing something else builds on a purely classical intuition and wouldn't require quantum mechanics to explain if this was all we observed. The uncertainty in quantum mechanics is fundamental (to q…

Post by wodenokoto » Sat, Apr 20, 2019, 9:50 AM UTC

david927 wrote: post #64

Sylos wrote: post #35

Earlier quoted context omitted.

> This is a common error. Macroscopic "everyday" objects don't have a definite position and momentum. Macroscopic objects are quantum objects. But when the mass is big enough, the position and momentum can be defined simultaneously with an error that is so small that you can just ignore the uncertainty and approximate them as classical objects. To put this into simpler terms: Whenever we measure something, we need to…

That's a nice explanation but doesn't it give the impression that if we could find a better way to do that experiment, we could find a way around the problem, when instead it's a fundamental limit on what we can know about a quantum system?