Конспект лекций по статистической физике. Коренблит С.Э - 24 стр.

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    Hc%b(t) %b(t)Hc  [H;
                       c %b(t)]; ¢ ¢¨¤¥: ih (@ %b(t)=@t) = [H;
                                                             c %b(t)]: (2.17)
€­ «®£¨ç­® à §«¨ç¨î ª« áá¨ç¥áª¨å ãà ¢­¥­¨© ƒ ¬¨«ìâ®­ (1.9) ¨ ‹¨-
㢨««ï (1.23), ãà ¢­¥­¨ï ¤¢¨¦¥­¨ï ®¡ëç­ëå ®¯¥à â®à®¢ ¢ £¥©§¥­¡¥à£®¢-
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îâáï ®â (2.17) å à ªâ¥à®¬ ¯à®¨§¢®¤­®© ¨ ®â­®á¨â¥«ì­ë¬ §­ ª®¬ áâ®à®­.

3   Žá­®¢­®© ¯®áâã« â ª¢ ­â®¢®© áâ â䨧¨ª¨
   ‘«¥¤ãï ä®­ ¥©¬ ­ã (1927), ­ «®¦¨¬ ⥠¦¥ ãá«®¢¨ï (1.28) ¨ ­ á®®â-
¢¥âá⢨¥ <<: : :>> ¬¥¦¤ã ª¢ ­â®¢ë¬¨ ®¯¥à â®à ¬¨ bb ¨ ­ ¡«î¤ ¥¬ë¬¨ B .
‚¢®¤ï ®¯¥à â®àë cli = j'l ih'i j, ¨¬¥î騥 ¥¤¨­á⢥­­ë© ­¥­ã«¥¢®© l; i-
âë© ¬ âà¨ç­ë© í«¥¬¥­â à ¢­ë¬    P
                                      1 ¢ ¡ §¨á¥ (2.1) (¯®¤á¨á⥬ë 1), § ¯¨-
襬 ¢ ­¥¬ ®¯¥à â®à bb, ª ª bb  i;l bli cli, ¨ ¢¢¥¤¥¬ ¬ âà¨æã %il (t) = <<cli>>.
’®£¤ : ¬€ªà®á®áâ®ï­¨¥ ¯®¤á¨áâ¥¬ë ¢ ¬®¬¥­â ¢à¥¬¥­¨ t ¯®«-
­®áâìî ®¯à¥¤¥«ï¥âáï § ¤ ­¨¥¬ áâ â¨áâ¨ç¥áª®£® ®¯¥à â®à %b(t)
(¬ âà¨æë ¯«®â­®á⨠¥¥ ¬ˆªà®á®áâ®ï­¨©), ­ ¡«î¤ ¥¬ ï B ¥áâì
á।­¥¥ ¯® â ª®¬ã á®áâ®ï­¨î ®â ®¯¥à â®à bb, ®â¢¥ç î饣® í⮩
¤¨­ ¬¨ç¥áª®© ¢¥«¨ç¨­¥ B, ®¯à¥¤¥«ï¥¬®¥ ä®à¬ã«®© (2.5):
                       b > = X %il bli  Tr(%bbb); Tr(%b) = 1:
                 B = <                                                  (2.18)
                                 i;l
Š« áá¨ç¥áª¨© ¯à¥¤¥« h ! 0 ãà ¢­¥­¨ï ä®­ ¥©¬ ­ (2.17) ¤ ¥â ãà ¢­¥-
­¨¥ ‹¨ã¢¨««ï, á ãç¥â®¬ ¯à ¢¨« ᮮ⢥âáâ¢¨ï ¬¥¦¤ã ª®¬¬ãâ â®à®¬ ¨
                           c %b] ! fH; %g. à¨ í⮬ ä®à¬ã«ë (2.18) ¥áâ¥-
᪮¡ª®© ã áá®­ : (i=h )[H;
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¨ ­®à¬¨à®¢ª¨ ä §®¢®© ¯«®â­®á⨠(1.31). Ž¤­ ª® ¢¢¥¤¥­­ ï ¢ëè¥ ¬ âà¨æ
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á®á⮨⠢ ¯¥à¥å®¤¥ ª \ä㭪樨" ‚¨£­¥à , ®¯à¥¤¥«ïî饩 áâ â¨áâ¨ç¥áª¨©
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§®¢ ­¨ï ”ãàì¥ ¤«ï ª®®à¤¨­ â­®© ¬ âà¨æë ¯«®â­®áâ¨
                                           X
      R (fxgs1; fygs1) = hfxgs1j%bjfygs1i = hfxgs1 jki wk hk jfygs1i; (2.19)
                           Z                 k
       d (fqbgs ; fpbgs ) = ds z R (fqb + z=2gs ; fqb z=2gs ) e i(pb
z)=h:
       W      1       1                        1          1