Physics – High Energy Physics – High Energy Physics - Theory
Scientific paper
2009-07-29
Phys.Rev.D80:084046,2009
Physics
High Energy Physics
High Energy Physics - Theory
19 pages revtex, three eps figures incorporated
Scientific paper
10.1103/PhysRevD.80.084046
In the context of a microscopic model of string-inspired foam, in which foamy structures are provided by brany point-like defects (D-particles) in space-time, we discuss flavour mixing as a result of flavour non-preserving interactions of (low-energy) fermionic stringy matter excitations with the defects. Such interactions involve splitting and capture of the matter string state by the defect, and subsequent re-emission. Quantum fluctuations of the D-particles induce a non-trivial space-time background; in some circumstances this could be akin to a cosmological Friedman-Robertson Walker expanding-Universe, with weak (but non-zero) particle production. Furthermore the D-particle medium can induce an MSW type effect. We have argued previously, in the context of bosons, that the so-called flavour vacuum is the appropriate state to be used, at least for low-energy excitations, with energies/momenta up to a dynamically determined cutoff scale. In this work we evaluate the flavour-vacuum expectation value (condensate) of the stress-energy tensor of the (1/2)-spin fields with mixing in an effective low-energy Quantum Field Theory in this foam-induced curved space-time. We demonstrate, at late epochs of the Universe, that the fermionic vacuum condensate behaves as a fluid with negative pressure and positive energy, but alone it cannot lead to present-day accelerating Universes. One needs flavoured boson contributions for this purpose.
Mavromatos Nick E.
Sarkar Sarben
Tarantino Walter
No associations
LandOfFree
Flavour Condensates in Brane Models and Dark Energy does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Flavour Condensates in Brane Models and Dark Energy, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Flavour Condensates in Brane Models and Dark Energy will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-521644