| Автор | Roberto Iengo |
| Автор | Chuan-Jie Zhu |
| Дата выпуска | 1999-06-01 |
| dc.description | In this note we derive an explicit modular invariant formula for the two loop 4-point amplitude in superstring theory in terms of a multiple integral (7 complex integration variables) over the complex plane which is shown to be convergent. We consider in particular the case of the leading term for vanishing momenta of the four graviton amplitude, which would correspond to the two-loop correction of the R<sup>4</sup> term in the effective Action. The resulting expression is not positive definite and could be zero, although we cannot see that it vanishes. |
| Формат | application.pdf |
| Издатель | Institute of Physics Publishing |
| Название | Explicit modular invariant two-loop superstring amplitude relevant for R<sup>4</sup> |
| Тип | paper |
| DOI | 10.1088/1126-6708/1999/06/011 |
| Electronic ISSN | 1029- 8479 |
| Print ISSN | 1126-6708 |
| Журнал | Journal of High Energy Physics |
| Том | 1999 |
| Первая страница | 11 |
| Последняя страница | 011 |
| Выпуск | 06 |
