No Arabic abstract
We write the most general parity-even re-normalizable Chern-Simons term for massive axial-vector propagating torsion fields. After obtaining the most comprehensive action, we perform the causal structure analysis to see what self-interaction term must be suppressed. In view of such a restriction for the Lagrangian, we will obtain the field equations, investigating some of their properties.
The commonly-known Chern-Simons extension of Einstein gravitational theory is written in terms of a square-curvature term added to the linear-curvature Hilbert Lagrangian. In a recent paper, we constructed two Chern-Simons extensions according to whether they consisted of a square-curvature term added to the square-curvature Stelle Lagrangian or of one linear-curvature term added to the linear-curvature Hilbert Lagrangian [Ref. 4]. The former extension gives rise to the topological extension of the re-normalizable gravity, the latter extension gives rise to the topological extension of the least-order gravity. This last theory will be written here in its torsional completion. Then a consequence for cosmology and particle physics will be addressed.
We argue that a simple Yukawa coupling between the $O(3)$ nonlinear $s$-model and charged Dirac fermions leads, after one-loop quantum corrections, to a Meissner effect, in the disordered phase of the nonlinear $s$-model.
We study several aspects of the extended thermodynamics of BTZ black holes with thermodynamic mass $M=alpha m + gamma frac{j}{ell}$ and angular momentum $J = alpha j + gamma ell m$, for general values of the parameters $(alpha, gamma)$ ranging from regular ($alpha=1, gamma=0$) to exotic ($alpha=0, gamma=1$). We show that there exist two distinct behaviours for the black holes, one when $alpha > gamma$ (mostly regular), and the other when $gamma < alpha$ (mostly exotic). We find that the Smarr formula holds for all $(alpha, gamma)$. We derive the corresponding thermodynamic volumes, which we find to be positive provided $alpha$ and $gamma$ satisfy a certain constraint. The dependence of pressure on volume is unremarkable and strictly decreasing when $alpha > gamma$, but a maximum volume emerges for large $Jgg T$ when $gamma > alpha$; consequently an exotic black hole of a given horizon circumference and temperature can exist in two distinct anti de Sitter backgrounds. We compute the reverse isoperimetric ratio, and study the Gibbs free energy and criticality conditions for each. Finally we investigate the complexity growth of these objects and find that they are all proportional to the complexity of the BTZ black hole. Somewhat surprisingly, purely exotic BTZ black holes have vanishing complexity growth.
We use Dirac matrix representations of the Clifford algebra to build fracton models on the lattice and their effective Chern-Simons-like theory. As an example we build lattice fractons in odd $D$ spatial dimensions and their $(D+1)$ effective theory. The model possesses an anti-symmetric $K$ matrix resembling that of hierarchical quantum Hall states. The gauge charges are conserved in sub-dimensional manifolds which ensures the fractonic behavior. The construction extends to any lattice fracton model built from commuting projectors and with tensor products of spin-$1/2$ degrees of freedom at the sites.
Here, we provide a simple Hubbard-like model of spin-$1/2$ fermions that gives rise to the SU(2) symmetric Thirring model that is equivalent, in the low-energy limit, to Yang-Mills-Chern-Simons model. First, we identify the regime that simulates the SU(2) Yang-Mills theory. Then, we suitably extend this model so that it gives rise to the SU(2) level $k$ Chern-Simons theory with $kgeq2$ that can support non-Abelian anyons. This is achieved by introducing multiple fermionic species and modifying the Thirring interactions, while preserving the SU(2) symmetry. Our proposal provides the means to theoretically and experimentally probe non-Abelian SU(2) level $k$ topological phases.