Identical particles Definition and 69 Threads

hello, can we say that identical particles in atoms like electrons are entangled since their total wavefunction is antisymmetric when we swap the states? is there any condition for this entanglement?

My question is that is the fact, that all particles are either boson or fermions, only an empirical fact, or can it be argued theoretically too. The reason why I'm asking this is that I have not encountered anyone stating honestly, that it is an empirical fact only. But on the other hand, I...

Homework Statement I got two particles, spin-(1/2), in a box of finite length and I must compute the energy and wavefunctions for the three lowest states. The particles are in a singlet spin state. Homework Equations E = \epsilon_{1} + \epsilon_{2} +... The Attempt at a...

Will a double-slit experiment work (exhibit an interference pattern) with a source of photons that is just monochromatic or do the photons need to be in the same quantum state? More generally, do all properties of a source of quantum particles need to be identical in order for the double-slit...

Homework Statement Two non interacting particles in an infinite potential well. ψn and ψl conditions (n≠l) find <(x1-x2)^2> when: 1-)particles are distinguishable, 2-)particles are indistinguishable bosons 3-)particles are indistinguishable fermions

Identical Particles -- Silly question Homework Statement Reviewing for final, can someone check this really quick? Two non-interacting particles are in an infinite cube, each side of length L. Determine the two-particle wave function and also the energy of the ground state and the first...

Homework Statement In a frame S, two identical particles with electric charge q move abreast along lines parallel to the x-axis, a distance r apart and with velocity v. Determine the force in S that each exerts on the other, by use of the force law for a uniformly moving charge. I would...

I was calculating the cross section for a particular decay and saw that I was off by a factor of half from the known value.. Now, the decay has two identical particles in the final state and I seem to remember having read somewhere that this requires a factor of half...but I am not able to...

\sum^{3N}_{i=1}\frac{p^2_i}{2m}\leq E Why I can write this inequality? Is this E energy of system?

Homework Statement I need to find the mean square distance between the 2 particles. Before I can do that, I need the expectation of x_1^2 and x_2^2 , then x_1x_2. I an on the first part and got stuck.Homework Equations <X_1^2>=\int_0^L \int_0^L x_1^2 |\psi_{n,m}(x_1,x_2)|^2 dx_1dx_2 where...

what would the system of two identical paritcles with a spin, let's say s? I figure its different for symmetrical and anti-symmetrical spin states but how do you deal with the defined spin state s.

[SOLVED] Identical Particles in a 1-D Harmonic Oscillator Homework Statement Three particles are confined in a 1-D harmonic oscillator potential. Determine the energy and the degeneracy of the ground state for the following three cases. (a) The particles are identical bosons (say, spin 0)...

Homework Statement Find the wave function of the ground energy state for a system of two non-interacting, identical spin 1/2 particles in a potential well extending from x=0 to x=a. Don't forget to consider spin.Homework Equations The Attempt at a Solution Since the particles are fermions...

Homework Statement Five electrons (with mass m) whose interaction can be neglected, are in the same 3-dim harmonic oscillatorpotential V(x,y,z) = \frac k2 (x^2 + y^2 + z^2) What is the ground state energy? Homework Equations The Attempt at a Solution I have the energy for the...

Homework Statement There are identical particles in a harmonic potential V(x)=\frac{1}{2}m\omega^{2}x^{2}. The number of particles is 2N, where N is a positive integer. Homework Equations a) What is the system's Hamilton's operator for bosons in the second quantization? How about the...

Homework Statement Five non-interacting particles are placed in a three dimensional harmonic oscillator potential for which the single-particle energy is: E_n = (n_x + n_y + n_z +3/2)\hbar\omega What is the lowest energy of the five-particle system when the particles are: a)...

Homework Statement Two identical particles are descibed by: H(p,x)= H(p_{1},x_{1})+H(p_{2},x_{2}) where H(p,x)=\frac{p^{2}}{2m}+\frac{1}{2}m\omega^2x^2 Separate to CM, obtain energy Spectrum. Show it agrees with: H\psi (x_{1},x_{2}) = E\psi (x_{1},x_{2}) with \psi...

When discussing identical particles, it is said that a wave function must be either symmetric or antisymmetric wrt exchange of particles. Could we not have, in general, \psi(r_1,r_2)=e^{i\phi}\psi(r_2,r_1) since the overall factor is physically meaningless?

I briefly scanned back through old topics in this part of the Physics Forum, and didn't see any that seemed to bring up this exact issue, so... I have read in several popularizations of physics that the exchange of bosons between a pair of identical particles will cause attraction if the...