Line of Simultaneousness

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  \put(53,7){\vector(0,1){61}} \put(46,66){$ct_A$}
  \put(2,27){\line(3,1){110}}
  \multiput(53,28)(-12,12){2}{\circle*{2}}
  \put(77,52){\circle*{2}}
  \put(53,28){\vector(-1,1){11}} \put(53,28){\vector(1,1){23}}
  \put(54,23){$E_1$} \put(35,41){$E_2$} \put(71,53){$E_3$}
  \put(28,2){$B'$}   \multiput(30,7)(2,6){9}{\line(1,3){1.5}}
  \put(44,2){$B$}  \put(46,7){\line(1,3){17.5}}
  \put(51,2){$A$}   
  \put(60,2){$B''$} \multiput(62,7)(2,6){9}{\line(1,3){1.5}}
  \put(83,54){\line(1,-1){5}}
  \put(89,48){Gerade der} \put(89,44){Gleichzeitigkeit}
  \put(15,54){$\alpha=\alpha'$}
  \put(15,52){\line(1,0){10}}
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  \qbezier(60.906,51.717)(57.057,53.000)(53.000,53.000)
  % draw_arc P1=(54/43) P2=(53/40) P3=(53/41) r=26
  \qbezier(61.222,52.666)(57.219,54.000)(53.000,54.000)
  % \put(57.219,66.000){\makebox(0,0){$\alpha$}}
   \put(58.000,56.500){\makebox(0,0){$\alpha$}}
  % draw_arc P1=(6/40) P2=(5/40) P3=(8/41) r=20
  \qbezier(25.000,28.000)(25.000,31.246)(23.974,34.325)
  % draw_arc P1=(6/40) P2=(5/40) P3=(8/41) r=21
  \qbezier(26.000,28.000)(26.000,31.408)(24.922,34.641)
  \put(29.000,32.408){\makebox(0,0){$\alpha'$}}
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