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I really liked watching this lecture. It is very technical but it is good!

Lecture 2 - The Universal Principle of Risk Management: Pooling and the Hedging of Risks

Robert J. Shiller

To all my mates interested in Physics:
I was reading some fundamentals of relativity,

It’s interesting how everything started by Maxwell equations, and how classical mechanics
is not invariant for Lorentz transformations.
The thing that struck me is that the problem had three possible solutions:
1) Electromagnetism is only Lorentz-invariant and mechanics is only invariant on Galilean transformations.
2) The laws of physics must be Lorentz-invariant so mechanics needs to be fixed.
3) The laws of physics must be Galilean invariant so electromagnetism had to be fixed.

It’s so strange that Einstein succeeded in (2), because even today, electromagnetic and mechanical events
are not unified, we have “matter waves” and “light waves” and they’re treated separately (one follows
Dirac equation, the other, Maxwell equations).

I am so impressed at how good is the solution to inertial mass and gravitational mass unification, so that
inertial mass curves spacetime, we can only move on geodesic of spacetime, so we feel a “force” of gravity. Yet I think the mass-energy equivalence has got a lot more to tell us, as we constantly change
between them with a conversion factor.. we then go on and treat them differently.

Awaiting comments

Today I was writing a report and as usual I was searching the web
for quick solutions of common things like: how do I write the min over some
variables of some function in a LaTeX formula?
Search engines found for me many pages that were saying “there is explanation
for this on wikipedia” BUT.. that wiki page had changed!!!
It’s like linking a wrong page… interesting stuff.
Anyway this is the trick, taken from the history of the wiki (always great thing)

LaTeX has no built-in ‘'’\argmax”’ command. Some people get around this by using ‘'’\arg\max”’. This could be undesirable, because a subscripted variable will appear centered beneath the word “max”, instead of centered beneath the whole word.
An easy solution is to use: \underset{x}{\operatorname{argmax}}

Enjoy LaTeX!

Happy Hacking