Recent content by jomoonrain

thank you very much.i've got it.

It is said that every magnetic induction line is closed.but recently I happended to find one which isn't. Consider the magnetic field generated by a ring form circuit, the magnetic induction line which I have found is not closed is the one that go through the center of the circuit,which is...

thank you so much!

thanks for replying. but i cann't understand how the isolation affects the certainty.

well, I am so appreciated of your kindness.

well, i think they are both right. but the first statement, in my opinion, should better be related as follows: if we want to describe a physical system, we HAVE TO find its hamiltonian,which represents the total energy of the system, besides this method, no others exits. in classical...

:cry: thanks for you explanation but it's totally beyond my knowledge.

hi I am not quite aware of the "quantum noise". But i think if it is the apparatus' problem, the probability distributions then should also depends on the apparatus.while in fact it was determinated by the Hamiltonian which totally has no relation with the apparatus.And what is more, if the...

well,thanks but if this is the explanation, then there will be a problem here again. if we use the same apparatus to measure the same system(e.g.use a magnetic field to measure two identical non-zero-spin particle in succession),will the result be the same? well, of cause, we may still...

if there are two identical systems,in quantum mechanics(or any other theorem),according to schrodinger equation, they will evolve congruously.but from the instant of measuring,the evolution seems disobey its original principle----i mean the evolutions are not congruously any more. is that mean...

i think you can try to write the cos as a series form. P.S. the third formula in your statements seems...

in fact we can obtain every thing from the process of the derivation of the Euler-Lagrange equation. as long as the constraint is a holonomic constraint,and the F is conservative(so F=V's derivative),the L is T-V. and the follow things have no differences with the situations which have no such...

but i can't tolerate such an approximation,negligible never equal to NO i agree with you but the last word. i am wondering how you deduce such a conclusion. if you can accept that the Earth and the apple are equivalent,or there is an symmetry here, and form your point :"In this case, the...

yeah, of cause. in fact, we can obtain the conclusion directly from the observation of the physical existence of this system instead of the mathematical expression,as long as it is in a inertia frame.

the conservation law of energy: the kinetic energy of the block=the potential energy at the beginning=1/2kx(square) with x the distance the spring is compressed