Loop Quantum Cosmology and Spin Foams

Sep, 2009
11 pages
Published in:
  • Phys.Lett.B 681 (2009) 347-352
e-Print:
Report number:
  • IGC-09-9-1

Citations per year

20092013201720212025051015
Abstract: (Elsevier)
Loop quantum cosmology (LQC) is used to provide concrete evidence in support of the general paradigm underlying spin foam models (SFMs). Specifically, it is shown that: (i) the physical inner product in the timeless framework equals the transition amplitude in the deparameterized theory; (ii) this quantity admits a vertex expansion a la SFMs in which the M -th term refers just to M volume transitions, without any reference to the time at which the transition takes place; (iii) the exact physical inner product is obtained by summing over just the discrete geometries; no ‘continuum limit’ is involved; and, (iv) the vertex expansion can be interpreted as a perturbative expansion in the spirit of group field theory. This sum over histories reformulation of LQC also addresses certain other issues which are briefly summarized.
  • 98.80.Qc
  • 03.65.Sq
  • 04.60.Pp
  • 04.60.Kz
  • quantum cosmology: loop space
  • spin: foam
  • geometry: discrete
  • expansion: vertex
  • Friedman model
  • perturbation theory