BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:What spatial geometry does the (2+1)-d QFT vacuum prefer?  - Toby 
 Wiseman (Imperial)
DTSTART:20181025T120000Z
DTEND:20181025T130000Z
UID:TALK111880@talks.cam.ac.uk
CONTACT:Dr. Carl Turner
DESCRIPTION:We consider (2+1)-d relativistic QFT on a product of time with
  a static two-space and study the vacuum free energy as a functional of te
 mperature and spatial geometry. Looking at both free scalars and fermions\
 , with and without mass (and in the scalar case including a curvature coup
 ling) we surprisingly find that any perturbation of a flat space is always
  energetically preferred to flat space. This is a UV finite effect\, insen
 sitive to any cut-off. We see the same behaviour for (2+1)-holographic CFT
 s  which we compute via the gravity dual.  In all these theories the same 
 is true non-perturbatively for low curvature deformations of flat space. W
 e consider the physical application of this to membranes carrying relativi
 stic degrees of freedom\, the vacuum energy of which then induce a tendenc
 y for the membrane to crumple. An interesting case is monolayer graphene\,
  which experimentally is observed to ripple\, and on large scales can be u
 nderstood as a membrane carrying massless Dirac degrees of freedom.
LOCATION:Potter Room (first floor\, Pav. B)
END:VEVENT
END:VCALENDAR