# Writings

### An Implicit Assumption about Expectation Values

A short note about an implicit assumption behind the notion of expectation values, and how it relates to economics applications.

### Matter field from diffeomorphism: on a theme of Capoferri and Vassiliev

I try to reformulate an idea of Capoferri and Vassiliev in the infinitesimal limit and see where it goes.

### A Weighted/Interpolated Young's Inequality

A follow up to my previous post on Young's inequality.

### Lie Groups

Some introductory notes about the definition and geometry of Lie groups, and their analysis.

### Oscillatory Solutions to the Heat Equation

As we all learned in a first course in PDEs, for "reasonable" initial data $u_0$, the solution to the linear heat equation …

### Dynamics of a Rigid Body

This post is about the formulation of the dynamics of a rigid body, under rotations, as dynamics on a Lie group. I'm writing this to …

### Models of Hyperbolic Plane

Some notes on the relationship between different models of hyperbolic plane

### The Translation Action on Function Spaces

Preliminaries Here's something I learned from Chongchun Zeng of Georgia Tech, while chatting over some hors-d'oeuvres at the AMS …

### Some Periodic Functions

Some non-intuitive facts about periodic functions

### An Elementary Proof of Young's Inequality

A proof of a generalized form of Young's inequality is given without the need of interpolation theory.