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HNQ
1:33 AM
1
Q: Effect of own magnetic field on stream of electrons (beam in vacuum and DC current in conductor)

PeltioSimilar, but not the same as: Magnetic field inside a charged stream because I am interested in what happens inside a conductor, but the behaviour in a free beam can help clarifying what I am asking. Let's consider a current of electrons (locally) limited to a cylindrical boundary of section A, f...

 
 
3 hours later…
HNQ
4:50 AM
1
Q: What is the apparent location of a real image formed by a lens?

d_bLet's say I place a tennis ball 1 m in front of a plane mirror. The mirror will form a virtual image of the tennis ball, and if I look in the mirror, it appears to me that there is a tennis ball sitting 1 m behind the mirror. If you asked me what the apparent location of the image was as I looked...

 
HNQ
5:33 AM
4
Q: Do particle & anti-particle pairs belong to the same field?

Quantum WonderWhen trying to understand the idea of virtual particles, the explanations for it seem to imply that, for example, electron-positron pairing happens within the fluctuating electron field, so does this mean that, when we speak of the electron field, it by itself is responsible for both electrons an...

 
 
11 hours later…
HNQ
4:54 PM
3
Q: Does an object approaching a black hole ever cross the combined event horizon of the black hole and itself?

Giorgos GOnce you start studying black holes, one of the first things you'll probably hear is that from an outsider's perspective objects falling into the black hole take an infinite time to do so due to time dilation. The object will asymptotically approach, but never reach the event horizon. As far as I...

 
 
5 hours later…
HNQ
9:39 PM
1
Q: What happens to the ring singularities when two Kerr black holes merge?

FlamethrowerImagine two Kerr black holes with ring singularities oriented in different axes (e.g. one horizontal and the other one vertical). If they merge, what will happen to these singularities? Will they form a kind of outline of a sphere or get disrupted in some way? And what if hundreds of these black ...

 
 
2 hours later…
HNQ
11:29 PM
1
Q: What does it mean that a state spontaneously break some symmetry?

dhqI'm currently reading this paper and I found the following statements confusing: On page 4: To study symmetric SRE states, we further demand that the ensemble of states ${|\psi_{I}\rangle}$ does not break the symmetries spontaneously. For exact symmetries this simply means that each individual s...

 

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