Theoretical Physics Seminar: Irene Valenzuela

  • Datum: –15.00
  • Plats: Zoom: https://uu-se.zoom.us/j/61066833009
  • Föreläsare: Irene Valenzuela (CERN and IFT Madrid)
  • Kontaktperson: Jacopo Sisti
  • Seminarium

Title: Where do we live in the string landscape?

Abstract: In this talk, I will discuss the possibility that our universe lies near the boundary of the field space in string theory, including the theoretical challenges and the exciting phenomenological implications. These boundaries share some universal properties imposed by quantum gravity (sometimes promoted to Swampland constraints) that resemble our universe, like weak couplings, approximate global symmetries or small (time-dependent) vacuum energy. However, it remains as an open challenge to get an accelerated cosmology. We study whether the runaway behaviour of stringy scalar potentials towards in finite distance can produce an accelerated expanding cosmology a la quintessence, finding some potential examples in F-theory flux compactifications. I will discuss the caveats of these examples and the comparison to Swampland bounds. Furthermore, a universal feature of these regions is that there is a light infinite tower of states which is correlated to the value of the vacuum energy. I will show how experimental constraints force this tower to correspond to a KK tower (of mass of order neutrino scale) of a single extra mesoscopic dimension of order 10^{-6) m, which we denote as the Dark Dimension.