BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Sebastian Mizera (Princeton\, Inst. Advanced Study) DTSTART:20230405T140000Z DTEND:20230405T150000Z DTSTAMP:20260423T021125Z UID:AnLy/24 DESCRIPTION:Title: Ev aluating one-loop string amplitudes\nby Sebastian Mizera (Princeton\, Inst. Advanced Study) as part of AnLy Strings and Fields online seminars\n \n\nAbstract\nScattering amplitudes in string theory are written as formal integrals of correlations functions over the moduli space of punctured Ri emann surfaces. It's well-known\, albeit not often emphasized\, that this prescription is only approximately correct because of the ambiguities in d efining the integration domain. In this talk\, we propose a resolution of this problem for one-loop open-string amplitudes and present their first e valuation at finite energy and scattering angle. Our method involves a def ormation of the integration contour over the modular parameter to a fracta l contour introduced by Rademacher in the context of analytic number theor y. This procedure leads to explicit and practical formulas for the one-loo p planar and non-planar type-I superstring four-point amplitudes\, amenabl e to numerical evaluation. We plot the amplitudes as a function of the Man delstam invariants and directly verify long-standing conjectures about the ir behavior at high energies.\n LOCATION:https://researchseminars.org/talk/AnLy/24/ END:VEVENT END:VCALENDAR