Recent content by valtorEN

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    What is an Infinite Potential Well?

    lol i recommend "Into To Quantum Mechanics" by DJ Griffiths or just searching Wikipedia! its fantastic! cheers nate
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    How Do You Find the Eigenenergies of a Rotor in an Electric Field?

    L_+=hbar*e^(i*φ)*(∂/∂θ+i*cot(θ)*∂/∂φ) L_-=hbar*e^-(i*φ)*(-∂/∂θ+i*cot(θ)*∂/∂φ) ok, i got them squared away how do i write cos(φ) in terms of L_+ and L_-? also, i would be interested in reading your thesis cheers nate
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    3rd order energy perturbation correction

    Homework Statement Derive the general expression of 3rd-order perturbation energy for a non-degenerate quantum system. Homework Equations for nth order we have (Ho-Eo)|n>+(H'-E1)|n-1> -E2\n-2>-En|0>=0 (given) also, <0|0>=1, <1|0> = <0|1>=0, <0|2>=<2|0>=-1/2<1|1>...
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    How Do You Find the Eigenenergies of a Rotor in an Electric Field?

    should i rewrite the eigenenergy as E=L^2/(2*I)? (to show its dependence of total angular momentum) also, how should i go about writing the cos(φ) into L+and or L- operators? L+=Lx+i*Ly L-=Lx-i*Ly
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    How Do You Find the Eigenenergies of a Rotor in an Electric Field?

    oops! I need to move my last post to a different problem, but thank you nrqed (is the qed stand for what i think it does ) i thought that the ladder ops would be important for the states |l'm'> let me see what i can work out cheers nate
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    How Do You Find the Eigenenergies of a Rotor in an Electric Field?

    got some of it! (i hope!) ok, i assume my question is a tough one, or that no one really understands what i am asking! :biggrin: here is what i have so far 1st i need B in spherical coordinates aside from that i am using B=B0x+B0y+B0z in cartesian coordinates say the B-field...
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    Solving Quantum Rigid Rotator Problems - Sam

    if Lz=(h/i)*(∂/∂φ), how can u write the energy in terms of the operator Lz? E=-hbar/(2*I)d^2Φ(φ)/(dφ^2)=EΦ(φ)
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    How to use extra term in radial equation

    Homework Statement Due to the modification of inner-shell electrons of a multi-electron system, the outer shell electron can feel an effective electrostatic potential as V(r)=-e^2/(4*π*eo*R)-lambda*(e^2/(4*π*eo*R^2)) ; 0<lambda≤1 Find the energy eigenvalues and wavefunctions of the...
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    Help particel in spherical delta potential well

    u'in(a)≠u'out(a) uout(a)=C*e^-(l*a) (simple enough) since l=0, the Neumann function nl(ka)=-B*a*(cos(a)/a) uin(a)=-B(cos(a)) ? u'in(a)B*sin(a) u'out(a)=-l*a*C*e^(-l*a) now i use u'in(a)≠u'out(a) to solve for Vo? can i get away with setting A=0 and D=0 like in the finite...
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    How Do You Find the Eigenenergies of a Rotor in an Electric Field?

    anyone still with me on this problem? i need to find the solutions for 1st order perturbation for this (degenerate) system! ouch! I have as the eigenenergies E(l,m)=l(l+1)*hbar^2/(2*I) now how do i use denegerate perturbation theory to solve for the 1st order correction to an...
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    Spin 1/2 in B-field polarization direction?

    ok, let me try this again H=-mu*B (this is the interaction energy between spin and B-field) for a particle of spin 1/2, with magnetic moment mu=mu(s)*S the Hamiltonian is h=1/2*m(p-q/c*A)^2-mu*B B=BX+BY+BZ (where i need to put B into spherical coordinates) so if i have the B-field in the...
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    Help particel in spherical delta potential well

    so for r≥a the solutions are called modified spherical Bessel Functions (lol) kl(kr) k^2=(2m|E|)/hbar^2 for boundary conditions (l=0) r=a (djl(Kr)/dr)/jl(Kr)|r=a- = (dkl(kr)/dr)/kl(kr)|r=a+ now since l=0, and j0(x)=sin(x)/x and k0(x)=e^-x/x (these are the solutions that join together at...
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    Help particel in spherical delta potential well

    so unlike the inf square well, the delta well does NOT meet the u'in(a)≠u'out(a) boundary condition?
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    Help particel in spherical delta potential well

    the exterior has no potential, so i assume that V=0, so there is no wavefunction that exists outside the well.
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