119347706
Counting black hole microscopic states in loop quantum gravity
Counting of microscopic states of black holes is performed within the framework of loop quantum gravity. This is the first calculation of the pure horizon states using statistical methods, which reveals the possibility of additional states missed in the earlier calculations, leading to an increase of entropy. Also for the first time a microcanonical temperature is introduced within the framework.
9159427
Poincaré invariance of anomalous gauge theories.
We establish the Poincare invariance of anomalous gauge theories in two dimensions, for both the Abelian and non-Abelian cases, in the canonical Hamiltonian formalism. It is shown that, despite the noncovariant appearance of the constraints of these theories, Poincare generators can be constructed which obey the correct algebra and yield the correct transformations in the constrained space.
8144931
Is there still a strong CP problem
Abstract The role of a chiral U (1) phase in the quark mass in QCD is analysed from first principles. In operator formulation, there is a parity symmetry and the phase can be removed by a change in the representation of the Dirac γ matrices. Moreover, these properties are also realized in a Pauli–Villars regularized version of the theory. In the functional integral scenario, attempts to remove the chiral phase by a chiral transformation are thought to be obstructed by a nontrivial Jacobian arising from the fermion measure and the chiral phase may therefore seem to break parity. But if one starts from the regularized action with the chiral phase also present in the regulator mass term, the Jacobian for a combined chiral rotation of quarks and regulators is seen to be trivial and the phase can be removed by a combined chiral rotation. This amounts to a taming of the strong CP problem.
42763584
Algebraic consistency in anomalous gauge theories.
A consistency condition for anomalous gauge theories is used to show that the usual form of the chiral anomaly is inadmissible and that a different but equivalent form yields Faddeev's Schwinger term.
121982569
MANIFEST AND NON-MANIFEST LORENTZ INVARIANCE FOR GAUGED SELF-DUAL BOSONS
The standard chiral way of gauging self-dual bosons can be described in either a non-manifestly Lorentz invariant formalism or a formalism where auxiliary fields are used to make Lorentz invariance manifest. The two descriptions are shown to be equivalent. The vector way of gauging, which is inconsistent in the second formalism, is shown to break Lorentz invariance in the first. Finally the new chiral way of gauging recently introduced by us in the first formalism is shown to admit a description in the second.
15654684
Time-reversal and parity conservation for gravitating quarks
The complex mass term of a quark does not violate time reversal or parity in gravitational interactions, in spite of an axial anomaly.
53655055
New symmetries of massless QED
A bstractAn infinite number of physically nontrivial symmetries are found for abelian gauge theories with massless charged particles. They are generated by large U(1) gauge transformations that asymptotically approach an arbitrary function εzz¯$$ \varepsilon \left(z,\overline{z}\right) $$ on the conformal sphere at future null infinity () but are independent of the retarded time. The value of ε at past null infinity () is determined from that on by the condition that it take the same value at either end of any light ray crossing Minkowski space. The ε ≠ constant symmetries are spontaneously broken in the usual vacuum. The associated Goldstone modes are zero-momentum photons and comprise a U(1) boson living on the conformal sphere. The Ward identity associated with this asymptotic symmetry is shown to be the abelian soft photon theorem.