Author: aakashl

Semiclassics: Quantum in form, Classical in spirit
Semiclassics is a wonderful regime where things look quantum but behave classically. What this precisely means I elaborate on in the document by bringing up a result from the paper by Dirac that would later inspire Feynmann. It can be found here. The point of this post is to demonstrate that semiclassics doesn’t need any…

But what really is symmetry? (Apparent vs. Actual Structure)
First post in a while: a fairly short one on some thoughts I had about symmetry. As I see it, symmetry is an artifact of us considering apparent instead of actual structures when analyzing systems. I talk about this and various examples. There are two other stories about symmetry I also hope to cover in…

Natural Units
I’m back! I decided to blog this because it didn’t feel substantial enough to have notes on its own and I couldn’t find a proper place for it elsewhere so here I am. Today, I wanted to discuss natural units i.e. the system under which , , etc. It became apparent to me that many…

A Natural Limit Definition
Often, the first exposure one gets to rigorous mathematics is the definition of a limit. Let’s consider what this is for a sequence. We say if This, at first sight, is ugly. It takes a while to even understand what it’s saying, longer to see why it works, and much longer to apply it. It’s…

Philosophy of Quantum Mechanics
Quantum Mechanics since its inception has been one of the most philosophically controversial concepts in all of physics. But what really is so confusing about quantum mechanics? The answer lies in two fundamental principles: locality and realism. Locality – locality asserts that all information and matter in the universe is limited by the speed of light. No…

Quaternions Revisited
It has admittedly been quite a while since my last post over a year ago. I thought I would restart the posts by revisiting one of the first topics I discussed on the website: quaternions. My previous post, upon review, seems to be quite uninformative on what the nature and use of them are which…

Calculus of Variations Part 2: Lines, Bubbles, and Lagrange
In the first part, we discussed the idea of a functional, what it means, and how to find its extrema using the calculus of variations. However, those equations don’t really capture how amazing and applicable calculus of variations really is so the following will be some examples of this. In fact, the drawn out results from…

Differential Forms Part 2: Differential Operators and Stokes Theorem
In the first post, we established a general intuition of how forms work and why they may provide a better geometric intuition of what is actually occurring. It was mentioned that these ideas extend the ideas of vector calculus so it seems natural to see how differential operators like gradient, curl, and divergence arise in…

Cool Things
Math is cool. Here are some cool things in math that I don’t think are really extensive enough for their own post but I still want to share. 1. The following is a great reason why.

Calculus of Variations Part 1: Establishing the Basis
Calculus of variations is an extremely useful and amazing tool in physics, math, computer science, and a variety of fields. Similar to how regular calculus is focused around functions and differentials, this field focuses on functionals and variations. A functional takes in a function and spits out a number. The following are examples of functionals.