compphysics / computationalphysics2 Goto Github PK

Hi,

I was looking over your page here: http://compphysics.github.io/ComputationalPhysics2/doc/pub/vmc/html/vmc-bs.html and I noticed some possible issues. I did not compile and test the programs, though.

This line:

I think it should be a division, not a multiplication, like this:
QForceOld /= h*waveFunctionOld;

A similar issue exists here:

double VMCSolver::QuantumForce(const mat &r, mat &QForce) is declared as returning double but it returns nothing. Doesn't seem to be an issue, since the returned value is not used anywhere, but probably it should be declared with void.

It might be the case that you introduced those issues on purpose, to let the students figure them out, in which case I'm sorry I interfered, but I thought I should report those just in case.

Thank you for putting those materials public!

Hi,

I was browsing the repository and I found Thijssen's book in doc/literature. I'm not really sure if it's ok to put it public like that (there might be some copyright issues), maybe you left it there by mistake?

By the way, it's an awesome book, I started many of my open source projects based on that book, although some went further than that.

Dear Professor,

I hope this message finds you well. I am a student interested in molecular physics, specifically the melting process of ice. I was wondering if it is possible to use quantum mechanics to solve this problem and if so, if you have any recommendations for resources or tools that I can use to start exploring this topic using a computational approach.
I am fascinated by quantum mechanics but the math is quite challenging for me, so I am looking for a way to start with a more accessible project. Any advice or guidance you can offer would be greatly appreciated.

Thank you for your time and consideration.

Best regards,

Ran

Hi,

Related with the previous bug report, I was looking over this page:
http://compphysics.github.io/ComputationalPhysics2/doc/pub/vmc/html/vmc-bs.html

I noticed some issues in the python code. I think that the gradient optimization code for the two non interacting particles case should accumulate the DeltaPsi value, so instead of:

        DeltaE = LocalEnergy(PositionOld,alpha)
        DeltaPsi = DerivativeWFansatz(PositionOld,alpha)
        energy += DeltaE
        DerivativePsiE += DeltaPsi*DeltaE

should be something like:

        DeltaE = LocalEnergy(PositionOld,alpha)
        val = DerivativeWFansatz(PositionOld,alpha)
        DeltaPsi += val
        energy += DeltaE
        DerivativePsiE += val*DeltaE

Also the computation of the GreensFunction looks suspicious at a very superficial look, as there, for example, it should be a division with the TimeStep.