# 共形對稱

（重定向自共形对称性

## 共形群

{\displaystyle {\begin{aligned}&M_{\mu \nu }\equiv i(x_{\mu }\partial _{\nu }-x_{\nu }\partial _{\mu })\,,\\&P_{\mu }\equiv -i\partial _{\mu }\,,\\&D\equiv -ix_{\mu }\partial ^{\mu }\,,\\&K_{\mu }\equiv i(x^{2}\partial _{\mu }-2x_{\mu }x_{\nu }\partial ^{\nu })\,,\end{aligned}}}

${\displaystyle D}$  生成位似变换

${\displaystyle K_{\mu }}$  生成特殊形转换

## 交換子

{\displaystyle {\begin{aligned}&[D,K_{\mu }]=-iK_{\mu }\,,\\&[D,P_{\mu }]=iP_{\mu }\,,\\&[K_{\mu },P_{\nu }]=2i(\eta _{\mu \nu }D-M_{\mu \nu })\,,\\&[K_{\mu },M_{\nu \rho }]=i(\eta _{\mu \nu }K_{\rho }-\eta _{\mu \rho }K_{\nu })\,,\\&[P_{\rho },M_{\mu \nu }]=i(\eta _{\rho \mu }P_{\nu }-\eta _{\rho \nu }P_{\mu })\,,\\&[M_{\mu \nu },M_{\rho \sigma }]=i(\eta _{\nu \rho }M_{\mu \sigma }+\eta _{\mu \sigma }M_{\nu \rho }-\eta _{\mu \rho }M_{\nu \sigma }-\eta _{\nu \sigma }M_{\mu \rho })\,,\end{aligned}}}

${\displaystyle x^{\mu }\to {\frac {x^{\mu }-a^{\mu }x^{2}}{1-2a\cdot x+a^{2}x^{2}}}}$
${\displaystyle {\frac {{x}'^{\mu }}{{x'}^{2}}}={\frac {x^{\mu }}{x^{2}}}-a^{\mu },}$

## 参考文献

1. Di Francesco; Mathieu, Sénéchal. Conformal field theory. Graduate texts in contemporary physics. Springer. 1997: 98. ISBN 978-0-387-94785-3.
2. ^ Di Francesco; Mathieu, Sénéchal. Conformal field theory. Graduate texts in contemporary physics. Springer. 1997: 97. ISBN 978-0-387-94785-3.
3. ^ Juan Maldacena; Alexander Zhiboedov. Constraining conformal field theories with a higher spin symmetry. Journal of Physics A: Mathematical and Theoretical. 2013, 46 (21): 214011. Bibcode:2013JPhA...46u4011M. arXiv:1112.1016. doi:10.1088/1751-8113/46/21/214011.