Wiener Khinchin Theorem
A proof of Wiener Khinchin theorem.
Integral of the month: \( \iint_S dt' dt f(t'-t) \)
When the function depends only on the difference of the parameters…
A refresher on statistical mechanics
A refresher on statistical mechanics based on Leonard Susskind’s lectures.
Lagrange Multipliers
A closer look into Lagrange Multipliers with the geometrical interpretation and a few examples.
Stirling approximation for factorial
Stirling’s approximation for the factorial function.
Integrating Gaussians like a boss!
This is a deep dive into Gaussian integrals.
Pandemic, home-schooling, and dragons: 2021 Edition
This is an update on a post from exactly one year ago: Pandemic, home-schooling, and dragons. When the pandemic hit the US in early …
Curl your Poynting vector
The Poynting vector is not the ground truth to explain the transport of energy in a circuit. It is redundant and does not help. It is …
The Legendre Transform
This is a deep dive in to the meaning of the Legendre transform.
Recoloring pixels with Python
A simple Python code to replace a selected color with another one.
