Search

Article

x

留言板

尊敬的读者、作者、审稿人, 关于本刊的投稿、审稿、编辑和出版的任何问题, 您可以本页添加留言。我们将尽快给您答复。谢谢您的支持!

姓名
邮箱
手机号码
标题
留言内容
验证码

ON SINGULARITIES OF AMPLITUDES IN A PERTURBATION THEORY

T. S. CHANG T. F. WU T. C. JIU

Citation:

ON SINGULARITIES OF AMPLITUDES IN A PERTURBATION THEORY

T. S. CHANG, T. F. WU, T. C. JIU
PDF
Get Citation

(PLEASE TRANSLATE TO ENGLISH

BY GOOGLE TRANSLATE IF NEEDED.)

  • This short paper gives two remarks on the singularities of the scattering amplitudes in a perturbation theory. First, it is pointed out that if the condition of stability is violated at several corners of a Feynmann diagram so that analytic extensions with respect to several external masses must be made, different sequences of carrying out the analytic extensions may lead to different positions of the singularities with respect to the final position of the integration contour (in a dispersion integral) and hence to different expressions for the amplitudes. Next, it is pointed out that the non-Landau singularities fall into two classes, of which one, say the first, is given by Cutkosky. For singularities in the first class, it is shown that they may be independent of the internal masses if and only if all the internal masses are equal or if the diagram is a loop. Their positions for the latter case are given. For singularities in the second class, it is shown that they are always independent of the internal masses and that they occur only for a very restricted set of diagrams.
  • [1]
Metrics
  • Abstract views:  6184
  • PDF Downloads:  361
  • Cited By: 0
Publishing process
  • Received Date:  28 September 1964
  • Published Online:  05 April 1965

/

返回文章
返回