| dc.description |
Noncritical M-theory in 2+1 dimensions has been defined as a double-scaling limit of a nonrelativistic Fermi liquid on a flat two-dimensional plane. Here we study this noncritical M-theory in the limit of high energies, analogous to the α′ ∞ limit of string theory. In the related case of two-dimensional Type 0A strings, it has been argued that the conformal α′ ∞ limit leads to AdS<sub>2</sub> with a propagating fermion whose mass is set by the value of the RR flux. Here we provide evidence that in the high-energy limit, the natural ground state of noncritical M-theory similarly describes the AdS<sub>2</sub> × S<sup>1</sup> spacetime, with a massless propagating fermion. We argue that the spacetime effective theory in this background is captured by a topological higher-spin extension of conformal Chern-Simons gravity in 2+1 dimensions, consistently coupled to a massless Dirac field. Intriguingly, the two-dimensional plane populated by the original nonrelativistic fermions is essentially the twistor space associated with the symmetry group of the AdS<sub>2</sub> × S<sup>1</sup> spacetime; thus, at least in the high-energy limit, noncritical M-theory can be nonperturbatively described as a ``Fermi liquid on twistor space.'' |
