Recent content by Idunno

The answer I came up with is to do with my ignorant reading of the Pauli Exclusion principle and the spin statistics theorem. The idea is that electrons in the same orbital are always 180 degrees out of phase. Which seems to be sort of what the spin statistics theorem says? (you probably won't...

Ok, so it takes energy to move the vorticies? Does that mean there is resistance of a sort in the superconductor? You'd think there would be no resistance to moving the charge around, but of course, I don't know. What about eddy currents in the conductive material of the magnet?

I agree. I think that if I ever do teach it, I should mention multiple interpretations. I'd just rather have an intuitive one. Help the students more. Situation is that it is now in the cirriculum, but optional, and I don't currently teach it, but I would like to if I can do a good job...

Threshold is still relevant, I think. If some of the wave packet is not interacting, the phase match has to be even better in the interacting part, if it's good enough, it goes over threshold, and collapse happens (all the energy is instantly relocated). The threshold is simply moved to a...

I'm not sure I'm following you, but I think I can reply like this: Would splitting a photon in two and only having one detector be an example of negative result or interaction free collapse? So you split a single photon in two with a beam splitter and the components of the photon go off in...

Hello, I am a high school physics teacher, and I have been thinking about a way to model quantum mechanics in an intuitive way in order to teach it better, but I don't want to lead my students down the wrong path. I am certainly no expert in quantum theory. In looking at the guidelines, I...

Oh yes, it slows down quickly. In trying to find an answer before posting here, I was all over the web, and I saw a similar question in the website Hyperphsyics here, but it wasn't answered.

Thank you for that, obviously a cylindrical magnet does much better than a cubical magnet at acting as a frictionless bearing. So what's up with the cube?

The superconductor does not allow a magnetic field to penetrate it, so charges in the superconductor circulate to create a magnetic field that is a sort of mirror image (is "mirror" the best word?) of the magnetic field from the magnet. The result is a magnetic field that allows the magnet to...

I got the opportunity a while ago to play around with a magnet floating above a superconductor cooled with liquid Nitrogen. The magnet was a little cube, and I spun it with a pair of tweezers. I was surprised at how quickly it stopped spinning, it seemed to stop much quicker than could be...

Well, suppose I want to explain this to a bunch of high school students. I think that what I'd say is something like "to find the mass of an object precisely as possible, one has to place the object in a device that allows you to relate it as best you can to Planck's constant, the second, and...

So, if I have some matter, and I want to know (as best I can) what the mass is, I have to put it in something like a Watt balance. That is, I have to put it in something that allows me to relate it to Planck's constant, the meter and the second. There is no set way to do this, the Watt balance...

Ah, I see, due to your position certainty going up, because with a nicely aimed collimated beam your position information is good enough and the wave packet small enough, you can't go through both slits at once. Thank you for the clairificaiton :)

Sorry to be... I don't know what the word is. But, if you get your beam of particles nice and confined and aimed really well and lined up with some very well cut slits, you can increase the percent getting through, right? But you never get 100%. Would it be 100% with a perfect beam and...

OK. Thanks for your time, much appreciated. :)