BEGIN:VCALENDAR
VERSION:2.0
PRODID:researchseminars.org
CALSCALE:GREGORIAN
X-WR-CALNAME:researchseminars.org
BEGIN:VEVENT
SUMMARY:Stephen Angus (Sogang University)
DTSTART:20261120T060000Z
DTEND:20261120T070000Z
DTSTAMP:20261114T002421Z
UID:EUPAC-TP/46
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/EUPAC-TP/46/
 ">Testing O(D\,D) string cosmology based on double field theory</a>\nby St
 ephen Angus (Sogang University) as part of Europe and Pacific Theoretical 
 Physics\n\n\nAbstract\nThe low-energy limit of string theory contains addi
 tional gravitational degrees of freedom\, the B-field and dilaton\, that a
 re not present in general relativity. Together with the metric\, these thr
 ee fields are naturally embedded in the $\\mathbf{O}(D\,D)$-symmetric fram
 ework of double field theory (DFT). Furthermore\, extending the $\\mathbf{
 O}(D\,D)$ symmetry to additional matter fixes a modified minimal coupling 
 in string frame and leads to a DFT version of Einstein's equations\, in wh
 ich the resulting DFT energy-momentum tensor is enhanced to include dilato
 n pressure and skew-symmetric contributions. After reviewing the DFT frame
 work\, I will explore its cosmological implications: I will describe how h
 omogeneous and isotropic backgrounds can be characterized by two equation-
 of-state parameters\, and I will present some analytic solutions that prov
 ide candidate models for bouncing cosmologies. Then I will discuss recent 
 progress toward testing $\\mathbf{O}(D\,D)$ cosmology\, including implicat
 ions for structure formation\, luminosity distance measurements\, and a po
 ssible non-Riemannian origin of the universe.\n
LOCATION:https://researchseminars.org/talk/EUPAC-TP/46/
END:VEVENT
END:VCALENDAR