前回のSummary Path Integral Quantization D d x path Integral D dx D d x x x x generating functional L L0 L1 Z [ , , ] DD D e 1 1 2 2 2 L0 ( ) (i m ) 2 2 1 4 L1 ( , , ) g 4 0 T ( (x1 ) (x j ) (xk ))) 0 (i )n n Z [ , , ] Z (0) (x1 ) (x j ) (x k ) 0 , 0, 0 i d 4 x L i d x L1 , , i i i 4 Z [ , , ] e 1 1 1 i d x 2 2 2 i m 4 e a Gauge Theory for gauge field G & spinor field Assume Lorentz inv., locality, superficial renormalizability & local gauge symmetry with Lie group G. Lie algebra g. i :parameter, depends on x G i gf ijk jG k i ig iT i j j j i i X X : generator of G X g e G gauge transformation [ X i , X j ] if ijk X k f ijk: structure constants of G T i: representation of Xi on [T i ,T j ] if ijk T k 1 i 2 Lagrangian L (G ) (i D m ) 4 i field strength G Gi G i gf ijk G jGk covariant derivative D ( igT G ) i i example SU(3)group of complex 3×3 matrices U withUU †=1 (unitary) & det U = 1 (special) generator X i i / 2 (i 1,2,,8) i Gell-mann matrices 0 0 1 0 1 1 0 0 , 2 i 0 0 0 0 0 0 1 0 4 0 0 0 , 5 0 1 0 0 i i 0 0 0 1 0 , 3 0 0 0 0 i 6 0 0 0 , 0 0 0 0 f commutators [i , j ] 2if ijk k f 123 1, f 458 f 678 0 0 1 1 0 1 0 , 8 3 0 0 0 0 0 0 0 0 1 , 7 0 0 1 0 0 i 0 0 1 0 0 2 0 i 0 ijkは完全反対称 147 165 246 257 345 376 f f f f f f 1/ 2 3 / 2, irreducible representations are specified by two integers 0 1 2 3 0 1 3 6 10 1 3* 8 15 2 6* 15* 27 3 10* ...... Path intdegral quantization of gauge theories L L0 L1 (G a , , ) としてみる 1 i j 1 i i 2 L0 ( G G ) G K G K 2 2 4 ∂K ∂∂2∂2∂ 0 generating functional Z [J a , , ] DGDD exp i d 4 x L G i J i e 4 i d xL1 , , iJ a i i 1 a 1 1 b i d x J ( K ) J 2 i m 4 e ∂ is inappropriate ∵ (K 1 ) does not exist. ∂ (K K 1 ) need gauge fixing we choose the gauge with G i B i 0 矛盾 ∂ (K1) does not exist. gauge fixing G i B i need gauge fixing we choose the gauge with G i B i gauge fixing G i B i Z [J ] DG i e iS iJ G J G J iG i d 4 x xi DG i e iS iJ G D ( G i( ) B i) det K yj i ( ) G (x ) i ( ) i ijk j k i G G gf G K xi ,yj j (y ) 4 ij 2 ijk k G ) (x y ) ( gf y j i dx i (y j (xk )) det xk dyi (y j ) 1 i gauge fixing G i B i Z [J ] DG i e iS iJ G J G J iG i d 4 x DG i e iS iJ G D ( G i( ) B i ) det K Gi (gauge不変性より) i ijk j k i G gf G i ( ) G (x ) i ( ) G K xi ,yj j (y ) 4 ij 2 ijk k G ) (x y ) ( gf Z [J ] DG e i iS iJ G D ( G B ) det K i i 無限大の定数 DG i e iS iJ G ( G i B i ) det K DG DB e i DG e i i i iS iJ G e 1 (B i )2 d 4x 2 i 物理はBi によらない 無限大の定数 e iS iJ G 1 ( G i ) 2 d 4 x 2 ( G B ) det K det K i i Z [J ] DG i e iS iJ G i 1 i 2 4 ( G ) d x 2 det K K xi ,yj ( gf ij 2 ijk G ) (x y ) K xi ,yj ( gf ij 2 ijk G k ) 4 (x y ) Z [J ] DG e i iS iJ G e i 1 ( G i ) 2 d 4 x 2 det K k 4 Z [J ] DG i e iS iJ G i 1 i 2 4 ( G ) d x 2 det K K xi ,yj ( gf ij i , ~ i Grassman number 2 ijk G ) (x y ) k 4 Faddeev Popov ghost i d 4 xd 4y~ i ( x ) K xi ,y j (y ) j ~ det K DDe i d 4 xd 4y~i ( x )( ij 2 gf ijk G k ) 4 ( x y ) (y ) j ~ DDe ~ DDe DD~e ~ i d 4 x~i ( x )( ij 2 gf ijk G k ) (y ) j i d 4 x ~ i ( ij gf ijk G k ) Z [J , , ] D G i DD~ e e j iS iJ G i 1 ( G i ) 2 d 4 x 2 i d 4 x ~ i ( ij gf ~ G k ) j i i~ ijk ~ Z [J , , , ] DGDD~DD fermionも加える ~i i i i ~ exp i d x L G J Lagrangian 4 i i L LG LGF LFP LF 1 i i ijk j k 2 LG ( G G gf G G ) 4 1 i 2 LGF ( G ) 2 ~i ij ikj k j LFP ( gf G ) ~ Z [J , , ] D G i DD~ e e iS iJ G i 1 ( G i ) 2 d 4 x 2 i d 4 x ~ i ( ij gf ~ G k ) j i i~ ijk ~ Z [J , , , ] DGDD~DD fermionも加える ~i i i i ~ exp i d x L G J Lagrangian 4 i i L LG LGF LFP LF 1 i i ijk j k 2 LG ( G G gf G G ) 4 1 i 2 LGF ( G ) 2 ~i ij ikj k j LFP ( gf G ) LF (i g T iG i m ) T i i / 2
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