arXiv subjects

David Guarrera

Publications and source records attributed to David Guarrera.

4 recordsLinked to original sources

arXiv2022

The evolution of scientific literature as metastable knowledge states

The problem of identifying common concepts in the sciences and deciding when new ideas have emerged is an open one. Metascience researchers have sought to formalize principles underlying stages in the life-cycle of scientific research, determine how knowledge is transferred between scientists and stakeholders, and understand how new ideas are generated and take hold. Here, we model the state of scientific knowledge immediately preceding new directions of research as a metastable state and the creation of new concepts as combinatorial innovation. We find that, through the combined use of natural language clustering and citation graph analysis, we can predict the evolution of ideas over time and thus connect a single scientific article to past and future concepts in a way that goes beyond traditional citation and reference connections.

cs.DL↗

arXiv2011

Holographic Fermi surfaces and bulk dipole couplings

Non-Fermi liquids can be studied using holographic duality. The low energy physics of a holographic Fermi surface is controlled by an emergent scale invariance. After reviewing these developments, we generalize the holographic calculation to include in the bulk action the leading irrelevant operator, which is a dipole coupling between the spinor field and the background gauge field. We find that this dipole coupling changes the attainable low-energy scaling dimensions, and changes the locations of the Fermi surfaces in momentum space. The structure of the holographic framework for non-Fermi liquids is, however, robust under this deformation.

hep-th↗

arXiv2009

Heterotic Flux Vacua from Hybrid Linear Models

We construct hybrid linear models in which the chiral anomaly of a gauged linear sigma model is canceled by the classical anomaly of a gauged WZW model. Semi-classically, this corresponds to fibering the WZW model over the naive target space of the sigma model. When the gauge group is abelian, we recover known non-Kahler compactifications; non-abelian models describe novel quasi-geometric flux vacua of the heterotic string.

hep-th↗

arXiv2007

Papapetrou Energy-Momentum Tensor for Chern-Simons Modified Gravity

We construct a conserved, symmetric energy-momentum (pseudo-)tensor for Chern-Simons modified gravity, thus demonstrating that the theory is Lorentz invariant. The tensor is discussed in relation to other gravitational energy-momentum tensors and analyzed for the Schwarzschild, Reissner-Nordstrom, and FRW solutions. To our knowledge this is the first confirmation that the Reissner-Nordstrom and FRW metrics are solutions of the modified theory.

gr-qc↗