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1 Primary & Middle School Mathematics1–9 年级在线 2 High School Mathematics10–12 年级在线 3 University Mathematics — Year 1本科一年级在线 4 University Mathematics — Year 2本科二年级在线 5 University Mathematics — Year 3本科三年级在线

1 Primary & Middle School Physics1–9 年级在线 2 High School Physics10–12 年级在线 3 University Physics — Year 1本科一年级在线 4 University Physics — Year 2本科二年级在线 5 University Physics — Year 3本科三年级在线

1 School Chemistry — Grades 1 to 121–12 年级在线 2 University Chemistry — Year 1本科一年级在线 3 University Chemistry — Year 2本科二年级在线 4 University Chemistry — Year 3本科三年级在线

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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 Leptons, quarks, hadrons？

Definition 26.1 University Physics — Year 3 · 第 26 章 — Particle Physics

Matter’s building blocks are spin- $\tfrac12$ fermions (Chapter 12, Chapter 14) in two families of six. Leptons feel no strong force: the electron, muon and tau (charge $-e$ , each heavier than the last) and their three neutrinos — nearly massless, nearly undetectable. Quarks come in six flavours — up, down, strange, charm, bottom, top — with charges $+\tfrac23e$ (u, c, t) and $-\tfrac13e$ (d, s, b), and they are never seen alone: confinement binds them into hadrons — three-quark baryons (proton $=$ uud, neutron $=$ udd) and quark–antiquark mesons (pion, kaon). Each particle has an antiparticle of identical mass and opposite charges (Exercise 26.8). Ordinary matter uses only the first generation — u, d, e, $\nu_{\text{e}}$ ; the two heavier copies differ, as far as anyone knows, only in mass. “Who ordered that?” physics still asks.

The Standard Model roster (charges in units of e). One column of it builds every atom; the other two are expensive echoes. Gravity, feeble beyond measure at these masses, has no seat at the table — the model’s most famous vacancy. — The Standard Model roster (charges in units of $e$ ). One column of it builds every atom; the other two are expensive echoes. Gravity, feeble beyond measure at these masses, has no seat at the table — the model’s most famous vacancy.

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