The Legend of Spinor


Fermions like protons,electrons,and quarks comprise(構成) all the ordinary matter in universe.

They do not obey the behavior typical of scalar,vector and tensor,but that of spinors.

So,what is a spinor?

It's essentially a two-component,vector-like quantity with special transformation property,in which rotations and Lorentz boosts are built into the overall formalism.

 

Spinors were originally introduced by Elie Cartan in 1913and subsequently greatly expanded upon by Hermann WeylRichard Brauer and Oswald Veblen

Spinors were found to be absolutely  indispensible(不可或缺的)in describing the behavior of fermions:electrons,protons,neutrons and the like.

 

No one fully understands spinors. Their algebra is formally understood,but their geometrical signuficance is mysterious.

In some sense they describe the "square root" of geometry and,just as uderstanding the concept of sqr(-1) took centuries,

the same might be true of spinors.----Sir Michael Atiyah

The simplest approach to explain spinors is Lorentz group theory.Lorentz transformations of rotations and boosts.

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 William O. Straub :A Child's Guide to Spinors

這裡有些有趣的東西  例如 Differential Forms for Physics Students

 

   img1.gifThe notion of electron spin was first surmised(推測) in 1922 by Stern and Gerlach,

and confirmed by Uhlenbeck and Goudsmit three years latter.

Otto Stern 1888-1969

Walther Gerlach 1889-1979

George Uhlenbeck 1900-1988   Samus Goudsmit  1902-1978

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薛丁格 狄拉克    Dirac relativistic electron equation :img2.gif

1927年 年僅25歲的狄拉克意識到 質量極小的電子極易加速到接近光速,而對於這種高速電子的完整描述

應該考慮將相對論方程式與量子力學方程式相結合.

他把狹義相對論引進薛丁格方程式 創立了相對論性質的波動方程式---狄拉克方程式 p.164

於是,真空不是一無所有,而是像負能量電子組成的汪洋大海...

1931年 狄拉克提出正電子的概念 ,1932年 Carl David Anderson發現[反物質](1936年 諾貝爾獎)

粒子的自旋與特點  p.182

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Anthony Zee(徐一鴻) [Quantum field theory in a nutshell]

 二十世紀物理最重要的計算,指的是什麼?

 [表現(representation) 隨處可見] 席南華教授

把一個對象的代數結構再現於一個由線性變換或矩陣構成的具體對象上

img1.gif費米 (Enrico Fermi 1901-1954)

玻色 (Satyendra Nath Bose 1894-1974)

所有粒子都能以自旋分類為費米子與玻色子

玻色-愛因斯坦凝態(condensed state)

  

  1. How to find the solution of the Dirac equation for the hydrogen atom    

   An Introduction Theory of Spinors      Moshe Carmeli 1933-2007   [The First Six Days of The Universe]  [ResearchGate]

                                                                         Shimon Malin 1937-2017     [ResearchGate]

  1. Introduction to Group Theory
  2. Representation Theory
  3. The Lorentz and SL(2,C) Groups
  4. Two-component Spinors
  5. Maxwell,Dirac and Pauli Spinors
  6. The Gravitational Field Spinors
  7. The Gauge Field Sponors
  8. The Euclidean Gauge Field Spinors

  1. 量子的星際飄移                              高鵬
  2. Differential Geometry in Physics      Gabriel Lugo      [ResearchGate]
  3. An Introduction Theory of Spinors   Moshe Carmeli and Shimon Malin
  4. 物理學家用微分幾何                     侯伯元 侯伯宇
  5. What's a Pauli matrix       Spinors in Spacetime Algebra and Euclidean 4-Space     Garret Sobczyk