I know this is an easy question but I want to confirm that I've got this right.
The wavefunction \psi(r) can be expressed as a linear sum of orthonormal eigenfunctions \phi_n(r) by
\psi(r) = \sum a_n\phi_n(r).
Derive an expression for the coefficients a_n.
I think the answer is a_n...
You need a decent textbook to understand QM. Something like Mandl or French or something similar to those. Then you'll need another one, and then another. And you need to like maths.
If you are looking for older papers, you WILL need a university library, or at least membership at one. If you...
I've studied this for my dissertation so i can explain it easily.
A qubit in the analogy of a bit in quantum computer. Unlike a classical computer, which takes values 0 and 1, a qubit is both at the same time. This is called a superposition of states. When you apply your operation to the...
Ok I think I've got this. (Credit also to Mehring in this thread http://www.advancedphysics.org/viewthread.php?tid=1374)
I'm going to go through the question now from the beginning and we'll see if it's all correct...
a) H = a\left(\begin{array}{cc}1&2\\2&1\end{array}\right)
b)...
Hey Norman,
Surely the question gives me |2> as eigenvectors, right? I'm still a little miffed, I think someone is just going to have to post the answer and explain it. My lecturer didn't make me understand it fully either :-(
For part i):
<H> = <2|H|2> = <2|(2a|1>+a|2>)> = a
The explanations are equivalent. With regards to Sm 4f^6, then n=4, l=3, L=\sqrt{l(l+1)}\hbar and I'm not sure how to interpret the 6.
With regards to your first question, the ms and ml states are simply the number of possible states at that level. When doing spin orbit coupling, (and this is...
This is an easy question to answer.
The electron has no internal structure because it has an infinite lifetime. By this I mean it does not decay to any lower order components. We can show this is true because we know what all the other reactions of the electron should be and they fit together...
I know that generally speaking entanglement of photons is done using 'parametric down conversion', where photons are collided in a material exhibiting non linear refractive indices. This process renders two entangled photons.
For the purpose of quantum cryptography, people are trying to do...
Hi Patrick, thanks for your speedy reply!
For ii) I have been attempting use Born's rule however I still find myself at a loss. The key things I ask myself here are:
The system is in state |2>, which is NOT an eigenstate of the hamiltonian, therefore there is uncertain energy (which we...
That's it's effective kinematic mass, not it's gravitational mass. All it means is that the faster something goes, the harder it is to accelerate further, and becoming infinite at the speed of light, this makes this an unreachable limit (you would have to push infinitely hard).
The mass is...
No, everything is conserved nicely.
Re: Heisenberg uncertainty principle, this indicates that the conservation of energy can be broken but only for a time so short that we are unable to observe it. Therefore we know that this must happen otherwise many reactions in particle physics (and the...
Hi,
I just want to ask a simple question about quantum mechanics...
This question appears in it's original form here:
http://www.chriscentral.com/physics/PC3101.PDF (question 2)
I have had a go and put some notes into the text below... I am stuck on parts c) (ii) and (iii).
Any help...