Gravitational Scattering Amplitudes and Closed String Field Theory in the Proper-Time Gauge

• Published in: EPJ Web of conferences Vol. 168; p. 7004
• Main Author: Lee, Taejin
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Les Ulis EDP Sciences 01-01-2018
• Subjects: Amplitudes; Field theory; Gravitation theory; Gravitons; Magnetic fields; Representations; Scattering; String theory
• ISSN: 2100-014X; 2101-6275; 2100-014X
• DOI: 10.1051/epjconf/201816807004

We construct a covariant closed string field theory by extending recent works on the covariant open string field theory in the proper-time gauge. Rewriting the string scattering amplitudes generated by the closed string field theory in terms of the Polyakov string path integrals, we identify the Fock space representations of the closed string vertices. We show that the Fock space representations of the closed string field theory may be completely factorized into those of the open string field theory. It implies that the well known Kawai-Lewellen-Tye (KLT) relations of the first quantized string theory may be promoted to the second quantized closed string theory. We explicitly calculate the scattering amplitudes of three gravitons by using the closed string field theory in the proper-time gauge.