A letter on the second anniversary of Nora’s crossing
A letter on the second anniversary of Nora's crossing
Sam Zhang
Latest posts
An illusion of predictability in scientific results
Even experts think / that well-estimated means / are certain outcomes. (Haiku summary due to MSR poets Dan and Jake). Click the thumbnail for a mini-explainer.
Elliptic curves and traveling wave solutions to the KdV equations
View traveling wave solutions to the KdV equations associated with (points of) elliptic curves.
Bayesian inference for COVID-19 testing
My brief foray into epidemiology at the start of COVID-19. Bayesian methods and interactive tools for informing COVID-19 surveillance testing strategies.
Ridge unfolding polytopes
Unfold 4-dimensional polytopes using their spanning trees.
Curve shortening
Deform a curve with a discrete curve shortening flow.
A catastrophe machine
Move the center of gravity of a wedge balancing on a table, and observe its corresponding catastrophe surface.
Linear regression, the old fashioned way
Perform ordinary least squares through a set of points with nails, springs, sleeves, and a frictionless rod.
A moduli space for triangles
A solution to a problem by Lewis Carroll using a clever moduli space. For fun, pick points on the moduli space, and watch triangles deform between them along geodesics.
The cross-section of a cylinder is an ellipse
A classical proof that the cross-section of a cylinder is an ellipse. I have no idea why, but this is the most popular blog post on my website.