We study renormalizable Lorentz invariant stable quantum field theories in two space-time dimensions with instantaneous causal structure (causal ordering induced by the light "cone" time ordering). These models provide a candidate UV completion of the two-dimensional ghost condensate. They exhibit a peculiar UV/IR mixing-energies of all excitations become arbitrarily small at high spatial momenta. We discuss several phenomena associated with this mixing. These include the impossibility to reach a thermal equilibrium and metastability of all excitations towards decay into short-wavelength modes resulting in an indefinite turbulent cascade. In spite of the UV/IR mixing in many cases the UV physics can still be decoupled from low-energy phenomena. However, a patient observer in the Lineland is able to produce arbitrarily heavy particles simply by waiting for a long enough time.
|Original language||English (US)|
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|State||Published - Nov 29 2011|
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Physics and Astronomy (miscellaneous)