TY - JOUR

T1 - Comments on the high energy limit of bosonic open string theory

AU - Chan, Chuan Tsung

AU - Ho, Pei Ming

AU - Lee, Jen Chi

AU - Teraguchi, Shunsuke

AU - Yang, Yi

N1 - Funding Information:
The authors thank Masako Asano and Hiroyuki Hata for helpful discussions. This work is supported in part by the National Science Council, Taiwan, ROC and National Center for Theoretical Sciences, Hsinchu, Taiwan, ROC (grant NSC 94-2119-M-002-001).

PY - 2006/8/14

Y1 - 2006/8/14

N2 - In previous works, ratios among four-point scattering amplitudes at the leading order in the high-energy limit were derived for the bosonic open string theory. The derivation was based on Ward identities derived from the decoupling of zero-norm states and was purely algebraic. The only assumption of the derivation was that the momentum polarization can be approximated by the longitudinal polarization at high energies. In this paper, using the decoupling of spurious states, we reduce this assumption to a much weaker one which can be easily verified by simple power counting in most cases. For the special cases which are less obvious, we verify the new assumption for an example by saddle-point approximation. We also provide a new perspective to our previous results in terms of DDF states. In particular, we show that, by using DDF states, one can easily see that there is only one independent high energy scattering amplitude for each fixed mass level.

AB - In previous works, ratios among four-point scattering amplitudes at the leading order in the high-energy limit were derived for the bosonic open string theory. The derivation was based on Ward identities derived from the decoupling of zero-norm states and was purely algebraic. The only assumption of the derivation was that the momentum polarization can be approximated by the longitudinal polarization at high energies. In this paper, using the decoupling of spurious states, we reduce this assumption to a much weaker one which can be easily verified by simple power counting in most cases. For the special cases which are less obvious, we verify the new assumption for an example by saddle-point approximation. We also provide a new perspective to our previous results in terms of DDF states. In particular, we show that, by using DDF states, one can easily see that there is only one independent high energy scattering amplitude for each fixed mass level.

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U2 - 10.1016/j.nuclphysb.2006.05.023

DO - 10.1016/j.nuclphysb.2006.05.023

M3 - Article

AN - SCOPUS:33745685951

VL - 749

SP - 266

EP - 279

JO - Nuclear Physics B

JF - Nuclear Physics B

SN - 0550-3213

IS - 1-3

ER -