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zinDo
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Homework Statement
A system of bosons or fermions trapped in a potential.
I'm being asked to write the Hamiltonian in 1st and 2nd quantization and "describe the ground state" of the system.
My main question is: what does it mean to describe the ground state? What should I look for? Should I look for the lowest energy?
Homework Equations
1 dimensional MOT-trap: ##V(x)=mw^2x^2/2##
The Attempt at a Solution
My attempt for writing the hamiltonian:
1st quantization ##H=\sum_{i=1}^{N}\frac{p_i^2}{2m}+\frac{1}{2}mw^2x_i^2##
2nd quantization: ##H=\int dx \psi^{\dagger}(x)\left[-\frac{\hbar^2}{2m}\nabla^2+\frac{1}{2}mw^2x_i^2\right]\psi(x)##
Where ##\psi(x)## isthe field operator.
Do you think this is enough? Are the hamiltonians equal for both bosons or fermions? Am I missing all the important stuff?
As for describing the ground state I don't know, my attempt has been writing down the many-body wavefunction (I don't know why, just to put something) for each case and explain that bosons can all be at the ground state and fermions have the exclusion principle.
##\Psi^{(S)}=N_S\sum_p \phi_1(x_1) \phi_2(x_2)... \phi_N(x_N)##
##\Psi^{(A)}=N_A\sum_p sgn(p)\phi_1(x_1) \phi_2(x_2)... \phi_N(x_N)##
Any advice/guidance?
Thanks