There's also beta, which despite being the next greek letter, isn't the same at all! Beta is a measure of the price correlation between an asset and some benchmark in terms of volatility. Beta of 1 means that the asset moves in lockstep with the benchmark. Low beta means the asset doesn't move as much as the benchmark and high beta means the asset moves a lot compared to the benchmark. Tech IPOs are often high beta compared to the S&P 500.
Anyway, finance has a lot of intellectually challenging problems that happen to overlap well with people trained to build mathematical models that attempt to describe stochastic processes. CS, Physics, Stats, some branches of pure Mathematics -- all have direct applications in the work they do to some aspect of being able to understand and predict markets.