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A Waldron

Publications and source records attributed to A Waldron.

4 recordsLinked to original sources

Quantum cosmology and conformal invariance.

According to Belinsky, Khalatnikov, and Lifshitz, gravity near a spacelike singularity reduces to a set of decoupled one-dimensional mechanical models at each point in space. We point out that these models fall into a class of conformal mechanical models first introduced by de Alfaro, Fubini, and Furlan (DFF). The deformation used by DFF to render the spectrum discrete corresponds to a negative cosmological constant. The wave function of the Universe is the zero-energy eigenmode of the Hamiltonian, or the spherical vector of the representation of the conformal group SO(1,2). A new class of conformal quantum mechanical models with enhanced ADE symmetry is constructed, based on the quantization of nilpotent coadjoint orbits.

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Gauge invariances and phases of massive higher spins in (anti-) de Sitter space.

The (m2,Lambda) plane of spin s>1 massive fields in (anti-) de Sitter space backgrounds is shown to consist of separate phases, divided by lines of novel "partially massless" gauge theories that successively remove helicities, starting from the lowest, 0 or +/-1/2. The norms of the excluded states flip as the gauge lines are crossed and only the region containing the massive Minkowski theory is unitary. The partially massless gauge theories are unitary or not, depending on the ordering of the gauge lines. This "level splitting" of massless Minkowski gauge theories is specific to nonzero Lambda.

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