So it is wrong to normalize the function with the two delta functions that he gives using ##<aa>=1## because it actually goes to infinity.
So how could we normalize ##ψ(x)=δ(xa)+δ(xa)## in a correct way ?
Hello there !
I found this discussion http://physics.stackexchange.com/questions/155304/howdowenormalizeadeltafunctionpositionspacewavefunction about dirac notation and delta function .
The one that answers to the problem says that ##<aa>=1## and ##<aa>=0## .
As far as i know:
1)...
Ok that was an easy integral but what if i have something more complicated like ##\int_{φ=0}^{2π} \int_{θ=0}^π \sin θ \ \cos θ~Y_{11}^*~Y_{11}~dθ \, dφ## ? If we use parity here we see that the parity of the integrated function is (1) and the integral must be zero! No calculations ! Just used...
Hello people!
I have ended up to this integral ##\int_{φ=0}^{2π} \int_{θ=0}^π \sin θ \ \cos θ~Y_{00}^*~Y_{00}~dθ \, dφ## while I was solving a problem.
I know that in spherical coordinates when ##\vec r → \vec r## :
1) The magnitude of ##\vec r## does not change : ##r' → r##
2) The angles...
Hello people ! Hope you are fine!
I tried to find the inner product that u can see below, between two different radial functions.
I was expecting to find zero but i found something nonzero.
You can see my two questions below in the photo.
So, in problem 3.5 he probably wanted to change the relation between ##\hat{A}## and ##\phi_n\rangle## to ##\hat{A}## ##\phi_n\rangle## = n ##\alpha_o\ ## ##\phi_{n+1}\rangle## (in order not to be anymore eigenstates of ##\hat{A}## ) but forgot to mention it?
1. Homework Statement
(Uploaded photo from Zettili Quantum Mechanics  Chapter 3  Solved problems 3.4 and 3.5)
Check at problem 3.4 the relation that he gives between operator A and state φn.
Now check the relation that he uses in problem 3.5 between A and φn again.
They are different while on...
i am concerned about the components !
Ok, let's say that i find that [H,L]=0 (so L angular momentum vector is being conserved) ! Do i have to find the commutators [H,Lx] , [H,Ly] , [H,Lz] or i am sure that they will all be zero due to the fact that [H,L]=0 ?
Hello ppl !
If i find that a physical quantity (lets say angular momentum operator vector L) is conservative (this means [H,L]=0  H=hamiltonian ) then its 3 components Lx , Ly and Lz are being conserved too ?
That happens with every conservative vector operator ? Like spin vector S and his...
Ok i think i understand why i can't have the same index on these two .
Moreover i think i found how i get rid of this minus ...
I must use the fact that εijk=εikj wright ?
Is now the solution correct ? (Uploaded photo)
Moreover , if i use , let's say the index m on x (not on x that comes from angular momentum , yes on x that is alone) , then i still have the minus on ih bar ... My solutions say that it should not be there ...
Homework Statement
The problem statement can be seen in the picture i uploaded.
Homework Equations

The Attempt at a Solution
The attempt to the solution can be seen in the picture i uploaded.
I reached to the A and i don't know how to proceed to the solution that is given below. How does...
Hello people !
I have been studying Zettili's book of quantum mechanics and found that spherical harmonics are written <θφL,M>.
Does this mean that θφ> is a basis? What is more, is it complete and orthonormal basis in Hilbert?
More evidence that it is a basis, in the photo i uploaded , in...