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The Dirac operator on SU_q(2)
(2005)
We construct a 3^+ summable spectral triple (A(SU_q(2)),H,D) over the quantum group SU_q(2) which is equivariant with respect to a left and a right action of U_q(su(2)). The geometry is isospectral to the classical case ...
Nonnegative mixed states in Weyl–Wigner–Moyal theory
(1988-03-21)
We classify the gaussian Wigner functions corresponding to mixed states and show that, unlike the case of pure states, not all nonnegative mixed states are gaussian.
On the kinematics of the last Wigner particle
(2019)
Wigner's particle classification provides for "continuous spin" representations of the Poincaré group, corresponding to a class of (as yet unobserved) massless particles. Rather than building their induced realizations by ...
The chirality theorem
(2018-03)
We show how chirality of the weak interactions stems from string independence in the string-local formalism of quantum field theory.
Quantum electrodynamics in external fields from the spin representation
(1994-07)
Systematic use of the infinite-dimensional spin representation simplifies and rigorizes several questions in quantum field theory. This representation permutes "Gaussian" elements in the fermion Fock space, and is necessarily ...
Distinguished Hamiltonian theorem for homogeneous symplectic manifolds
(1991-09)
A diffeomorphism of a finite-dimensional flat symplectic manifold which is canonoid with respect to all linear and quadratic Hamiltonians preserves the symplectic structure up to a factor: so runs the "quadratic Hamiltonian ...
Moyal quantization with compact symmetry groups and noncommutative harmonic analysis
(1990)
The phase-space approach to quantization of systems whose symmetry group is compact and semisimple is developed from two basic principles: covariance and traciality. This generalizes results and methods already implemented ...
The metaplectic representation and boson fields
(1991-12)
We construct explicitly the infinite-dimensional metaplectic representation and show how its use simplifies and rigorizes several questions in bosonic Quantum Field Theory. The representation permutes Gaussian elements in ...
Orbifolds are not commutative geometries
(2008)
In this note we show that the crucial orientation condition for commutative geometries fails for the natural commutative spectral triple of an orbifold M/G.
Stora's fine notion of divergent amplitudes
(2016-11)
Stora and coworkers refined the notion of divergent quantum amplitude, somewhat upsetting the standard power-counting recipe. This unexpectedly clears the way to new prototypes for free and interacting field theories of ...