Monthly Archives: January 2025

The purpose of this post is to explain several techniques for laser cooling and laser trapping of atoms. In order to better emphasize key conceptual points, it will take the approach of posing problems, followed immediately by their solutions. Problem … Continue reading →

Problem: Given a point light source emitting with a Hermitian bilateral \(k\)-space irradiance spectrum \(I(k)\) (i.e. for \(k\geq 0\), the total irradiance contained in the interval \([k,k+dk]\) is \(2I(k)dk\) and furthermore \(I(-k):=I^{\dagger}(k)\)), show that the corresponding fringes \(I(x)\) measured by … Continue reading →

Problem: What does the phrase “spectral line shape” mean? Solution: A spectrum is typically a plot of the intensity \(I(\omega)\sim|E(\omega)|^2\) of some underlying time domain signal \(E(t)\). Problem: What are the \(2\) most prominent kinds of spectra one encounters? Solution: … Continue reading →

Problem: Draw a DNA molecule. Annotate the terms nucleotides, phosphate group, deoxyribose, phosphodiester linkage, adenine, thymine, cytosine, guanine, nitrogenous bases. Problem: Draw an RNA molecule, and make similar annotations as for DNA. Problem: What is the typical length scale \(x_{\text{cell}}\) … Continue reading →