Harshdeep Chhabra

of the statement

wanted to know the validity

I heard somewhere that research in superconductivity is sort of stagnant currently

just use | directly, much more readable lol

but density is not

current is a macro thing

@nickbros123 what do you mean by macroscopic formula?

oh nice, I'm actually interning in an DFT lab right now so I just started learning like 3 weeks ago

oh sorry for the partial tag @naturallyInconsistent

how long have you been working with DFT? @na

lmao fair

so would you say HF is a better method since that uses proper SE which is antisymmetric?

so it just runs on a trial and error method till it gets convergence and that energy is probably right

or does it do some transformation from Kohn-Sham Wavefunction to normal SE wavefunction before showing is proper energy?

is that meaningless too?

but then what about the eigenvalue?

oh yea that is true too

wouldn't that make all of the calculation incorrect?

then it is not considering the anti-symmetry rule

no I get that then why does DFT get away with it by just taking the product?

like what information does slater det add

so what is the difference in a physical significance wise if I'm using slater det or if I'm just using a product of wavefunction

@naturallyInconsistent this ig yea

lol

actually if you google the definition of correlation is the difference of total energy from $E_{Hartree}$

both DFT and HF take exchange but only DFT takes correlation into account

@naturallyInconsistent if I've read correctly HF doesn't take correlation in account?

@naturallyInconsistent oh alright

where as it is generally the case that HF is less accurate than DFT

@naturallyInconsistent so wouldn't that make DFT less accurate?

ok maybe final year UG, but I'm not sure

personal research is different ig

at least not coursework

even in UG

quantum espresso never gets started I think

we also call it SHM and CoE in our education system

it might be a education system thing

convservation of energy and simple harmonic motion I suppose?

is he doing quantum espresso calculations in high school?

in hilbert space

since changing the position of any electron doesn't affect the whole thing

and technically even taking the product means that all electrons are indistinguishable

so in Hartree-Fock method we make a single slater determinant, how is that different than just taking product of all individual wavefunction (which DFT) does?

I apologize if my question seems naive I'm new to this topic thus I want to confirm if my understanding is correct

@ACuriousMind so there's no physical significance really and nothing changes it just shows that pauli principle is holding since technically the two slater determinant (or wavefunction) is different for both states?

then why change sign at all like what is the significance of saying that it changes sign?

then why does the determinant change sign?

@ACuriousMind but the definition of indistinguishable would be that if two electrons if they change position then nothing would change

If two electrons are indistuinguishable then why does the sign of slater determinant need to change when two electrons are interchanged in positions?

Anyone here familiar with tight binding method in DFT?