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1 Markets I: The Ecosystem and Exchange-Traded Markets市场在线 2 Markets II: Rates, FX and Credit市场在线 3 Markets III: Commodities, Energy and Crypto市场在线 4 Quantitative Methods方法在线 5 Derivatives and Volatility衍生品在线 6 Rates, Credit, XVA and Risk利率、信用与风险在线 7 Research Craft: Predictors, Backtests, Measurement, Portfolios研究在线 8 Strategies I: Equities and Futures策略在线 9 Strategies II: Volatility, Relative Value, Macro and the Bank Desks策略在线 10 Microstructure and Execution交易执行在线 11 Market Making and High-Frequency Trading做市在线 12 Machine Learning for Markets机器学习在线 13 Low-Latency Software技术在线 14 Networks, Hardware and Trading Infrastructure技术在线 15 Research, Data and Risk Platforms技术在线 16 The Desk and the Firm公司运营在线 17 The Industry: Firms, Roles and Careers职业发展在线 18 Interviews I: Maths, Probability and Speed职业发展在线 19 Interviews II: Markets, Trading Games and the Final Round职业发展在线 20 Interviews III: Code职业发展在线

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Physics · 术语表

什么是 Action variable？

Definition 2.14 University Physics — Year 3 · 第 2 章 — Hamiltonian Mechanics

For a one-degree-of-freedom system oscillating on a closed phase trajectory, the action variable is the enclosed area divided by $2\pi$ :

I = \frac{1}{2\pi}\oint p\,\dd q .

Adiabatic invariance. Left: as is slowly doubled, the phase ellipse changes shape at constant area, so E = I doubles. Right: hoisting the string of a swinging pendulum feeds energy into the swing in just the proportion that keeps I = E/ fixed. — Adiabatic invariance. Left: as $\omega$ is slowly doubled, the phase ellipse changes shape at constant area, so $E = \omega I$ doubles. Right: hoisting the string of a swinging pendulum feeds energy into the swing in just the proportion that keeps $I = E/\omega$ fixed.

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