Skip to main content

New answers tagged

0 votes

What is the purpose of the Quantum Fourier Transform or what does it operation achieve?

I've checked through the answer above and it's really a good one especially for newbies! Truth be told, it's my first time to learn about other applications of Quantum Fourier Transform (QFT) rather ...
Adam Darx's user avatar
0 votes

The relation between spectral function, Green function and particle number in many-body systems

The one particle Matsubara Green functions is defined via imaginary time ordering for bosons and fermions as $ G(\tau) = -\langle T(c(\tau) c^\dagger) \rangle = -\theta(\tau) \langle c(\tau) c^\dagger ...
M_kaj's user avatar
  • 436
2 votes

Alternative way to compute expectation value of momentum?

Yes, you can work out the expectation value of an operator in that way. The key thing to notice is that the expectation value does not depend on which basis you choose to work with. For example, it ...
Níckolas Alves's user avatar
2 votes

Why are power spectrum plots $l^2 P(l)$ instead of just $P(l)$?

This is for the simple reason that for a scale-invariant spectrum, $\ell(\ell+1)P(\ell)$ is constant on a logarithmic scale. From Understanding the Cosmic Microwave Background Temperature Power ...
Riley Scott Jacob's user avatar

Top 50 recent answers are included