End of Uncertainty: Quantum Mechanics in Human Perspective

[CyberShot]

Imagine humans had a size on the order of magnitude close to the size of a large planet. An electron, then, proportionality-wise, would roughly be the size of an apple. To us large-scale humans, the apple might seem quantum mechanical and unpredictable because it seems exceedingly tiny. But we all know apples are macroscopic objects. The large scale humans are thus limited in precision to measuring apples, and thus have to relegate to their equations of probability to feel good about themselves.

Now, going back to our normal sizes, the electrons may seem so tiny, but what if there were tiny humans (the size of molecules) to whom electrons would seem like apples? Classical laws would seem to apply.I'm sorry if it seems like I'm bashing QM, but I really can't go on pretending that the moon is not really there when nobody's looking at it.

 

[mquirce]

I share your opinion about Haisenberg uncertain principle, maybe because i have shallow knowledge about topics. It strange that all scientist of the worlld approve H.U.P.
I don't know how Planck has find constant "h" but togethr with it has calculatet the ultima constant o nature:
Now the physicists use the formula E = h / t and with this formula they create not one but miriad of universes giving the value of "t" = 0, that is creating from nothing an energy equal infinite.What about Planck Tpl.?
The last my opinion is that layman like myself is better to say "amen" and to shut up.
Cheers.

 

[ZapperZ]

Imagine humans had a size on the order of magnitude close to the size of a large planet. An electron, then, proportionality-wise, would roughly be the size of an apple. To us large-scale humans, the apple might seem quantum mechanical and unpredictable because it seems exceedingly tiny. But we all know apples are macroscopic objects. The large scale humans are thus limited in precision to measuring apples, and thus have to relegate to their equations of probability to feel good about themselves.

Now, going back to our normal sizes, the electrons may seem so tiny, but what if there were tiny humans (the size of molecules) to whom electrons would seem like apples? Classical laws would seem to apply.


I'm sorry if it seems like I'm bashing QM, but I really can't go on pretending that the moon is not really there when nobody's looking at it.

The HUP is merely a CONSEQUENCE of QM.

You should also note that your displeasure of it is based on a MATTER OF TASTES! This is a rather dubious reason to not accept something. Instead, try and look at ALL the quantum phenomena that we know of. Now see how those phenomena can be explained using your scenario that it is just a matter of scale. Do you honestly believe that physicists are THAT dumb and THAT accepting of QM without considering such other possibilities?

Zz.

 

[GDogg]

Apples are made of a gazillion particles. Electrons are not.

Like ZapperZ says, scale has nothing to do with it. What makes an apple classical is decoherence. It doesn't matter if apples or electrons seem bigger or smaller to us.

 

[The_Duck]

CyberShot, in your scenario the giant humans might indeed look in a microscope and observe apple-sized objects bouncing around randomly due to Brownian motion, or something. But they would not observe anything like quantum-mechanical effects. IMO the fundamental strange feature of quantum mechanics is not indeterminacy but interference of probability amplitudes, for instance in the double-slit experiment. Unless they cooled their experiment down to fantastically low temperatures or something, they could not observe interference in a double-slit experiment using apples. When they did manage to perform a double-slit experiment and observe interference, they would observe that their interfering waves seemed to obey the de Broglie relation lambda = hbar/p with the same hbar as we measure.

I really can't go on pretending that the moon is not really there when nobody's looking at it.

I think this is a pretty dumb way that some people have of talking about the weirdness of quantum mechanics. For instance there is the Bohmian interpretation of quantum mechanics, in which all particles, including the Moon's constituents, have objective, definite properties at all times, and there's no special role played by "observation," nor is there such a thing as "collapse" of the wave-function. Instead in this interpretation, something like "collapse" can be used as a good approximation to describe what happens when certain interactions occur that you might describe as measurements. The Bohmian interpretation does have some less-than-satisfying aspects. But you need not believe that "the Moon is only there when someone's looking at it."

In light of such things I would hazard a guess that most physicists don't really believe what is taught in intro QM classes--that there are really such special things as "measurements" that produce "wave-function collapse" because of all the problems such a view produces--for instance, what counts as a measurement that gets to collapse the wave-function? There are various answers to this, many ridiculous, for instance "consciousness," which is nonsense.

 

[lalbatros]

CyberShot,

Consider a precise experiment and try to analyse it, as physicists did it 100 years ago.
They had to swallow their conclusions, now it is your turn to swallow or to try another way.
Start with the diffraction of electrons, or even photons.
You will soon conclude your comparison is void, then you can still try other interpretations.
Some are available off the shelf: Bohmian mechanics, hidden variables.
QM has not yet been contradicted experimentally.

 

[G01]

I'm sorry if it seems like I'm bashing QM, but I really can't go on pretending that the moon is not really there when nobody's looking at it.

If you think that quantum mechanics supports the idea the moon does not have a definite position, then you do not understand quantum mechanics well enough to comment on it's validity.

The moon is a classical object, made up of an extremely large amount of atoms. The individual atoms are, of course, quantum objects, but grouped together, they interact in a way that "washes out" quantum effects. This is the decoherence effect everyone keeps bringing up. Thus, it is completely fine to assign the moon a definite classical position and trajectory. As previously mentioned, it's not about "scale" and "measurement precision." It's about composition and interactions between the constituent particles in a given system and the surrounding environment.

 

[pallidin]

Rest assured. If every living creature(human and otherwise) on Earth were suddenly vaporized, the entire universe would continue to exist without so much as a wink.