Heisenbergs Uncertainty Principle

[Count Iblis]

If you do a search on my posts, you'll see that I've mentioned this several times, including the exact reference to the PRL paper.

So what about this paper is relevant here?

Zz.

The fact that you can apply quantum mechanics in a pretty straightforward way to macroscopic objects. The interaction of the center of mass with the degrees of reedom in the mirror and rest of environment simply causes decoherence.

In case of tunneling of macroscopic object, I guess that such decoherence effects would supress the effect similar to the quantum zeno effect. In case of pencil balanced in its tip, I really don't see how you could end up with a longer theoretical maximum time for the pencil to remain balanced on its tip (there is no energy gap here).

 

[ZapperZ]

The fact that you can apply quantum mechanics in a pretty straightforward way to macroscopic objects. The interaction of the center of mass with the degrees of reedom in the mirror and rest of environment simply causes decoherence.

Er.. not really. Look at how difficult it is to do such a thing using the set-up they are suggesting.

Secondly, it requires that the photons actually to be the one doing "all the work", i.e. something coherent. We already know that this is what is the necessary ingredient. After all, we see superconductivity only when a large number of charge carriers are in a coherent state. The Delft/Stony Brook experiment reveals such superposition already, and this proposed experiment is simply extending the "size" of how we can detect superposition.

Again, if it is THAT obvious, QM would not be this mysterious.

But that is still besides the point of this thread. How is the detection of "superposition" in a coherent system somehow translates to your ability to apply it to a pencil tipping due to the HUP? Doc Al has given me an excellent reference that actually have debunked such a myth

Don Easton, Eur. J. Phys. 28 1097-1104 (2007).

I'd suggest people read that before adopting and perpetuating this idea further.

Zz.

 

[Count Iblis]

I can't download the full paper from here. Does the paper show anything nontrivial, something else besides the rather trivial observation that thermal fluctuations are more important than quantum fluctuations above some temperature T and that this T is rather low for a macroscopic pencil?

 

[ZapperZ]

I can't download the full paper from here. Does the paper show anything nontrivial, something else besides the rather trivial observation that thermal fluctuations are more important than quantum fluctuations above some temperature T and that this T is rather low for a macroscopic pencil?

Definitely yes!

Zz.