Elusive physical electron propagator in QED-like effective theories

We study the previously conjectured form of the physical electron propagator and its allegedly Luttinger type of behavior in the theory of the pseudogap phase of high-temperature copper-oxide superconductors and other effective QED-like models. We demonstrate that, among a whole family of seemingly gauge-invariant functions, the conjectured "stringy ansatz" for the electron propagator is the only one that is truly invariant. However, contrary to the results of the earlier works, it appears to have a negative anomalous dimension, which makes it a rather poor candidate to the role of the physical electron propagator. Instead, we argue that the latter may, in fact, feature a "super-Luttinger" behavior characterized by a faster than any power-law decay: G(x) ~ exp(-const ln^2|x|).Comment: Latex, 10 pages, no figure

Viable phenomenologies of the normal state of cuprates

We revisit the problem of constructing an elusive scaling theory of the strange metal phase of the cuprates. By using the four robust experimentally established temperature dependencies as the constitutive relations we then predict the scaling behaviors of a number of other observables, all those for which the reliable data are available being in agreement with experiment. Such predictions are also contrasted against the recent proposal inspired by the holographic approach, thus allowing one to critically assess the status of the latter.Comment: Latex, 4+ pages, no figure

Simulating holographic correspondence in flexible graphene

In the spirit of the generalized holographic conjecture, we explore a relationship between the bulk and boundary properties of non-interacting massive Dirac fermions living on a flexible surface, such as a sheet of graphene. We demonstrate that the boundary correlations can mimic those normally found in the system of one-dimensional interacting fermions, a specific form of such phantom interaction being determined by the bulk geometry. This geometrical interpretation of the boundary interaction effects offers a new insight into the possible origin of the more sophisticated types of holographic correspondence and suggests potential ways of visualizing 'analogue holography' in the experimentally viable environments.Comment: Latex, 4+ pages, no figure

Non-Fermi-Liquid Behavior of Compressible States of Electrons on the Lowest Landau Level

Experiments show that at even denominator fractions (EDFs) ($\nu=1/2, 3/4, 3/2$,...) the two-dimensional electron gas in a strong magnetic field becomes compressible, has no energy gap, and demonstrates the presence of an ostensible Fermi surface. Since this phenomenon results from a minimization of the interaction, rather than the kinetic energy, the EDF states might well exhibit deviations from a conventional Fermi liquid. We show that impurity scattering at EDFs and its interference with electron-electron and electron-phonon interactions provide examples of intrinsically non-Fermi-liquid transport.Comment: 5 pages, Latex. To appear in the Proceedings of the Euroconference on "Correlations in Unconventional Quantum Liquids" in Z.Phys.

Comment on "Electron spectral function and algebraic spin liquid for the normal state of underdoped$ high T_c superconductors"

Comment on the Letter by W. Rantner and X-G. Wen, Phys. Rev. Lett. v.86, p.3871 (2001).Comment: Latex, 1 pag