N ov 2 00 4 A Coherent Strategy for Quantum Gravity ∗

ua nt - p h / 06 11 11 6 v 1 1 0 N ov 2 00 6 Quantum mechanics on a circle : Husimi phase space distributions and semiclassical coherent state propagators

We discuss some basic tools for an analysis of one-dimensional quantum systems defined on a cyclic coordinate space. The basic features of the generalized coherent states, the complexifier coherent states are reviewed. These states are then used to define the corresponding (quasi)densities in phase space. The properties of these generalized Husimi distributions are discussed, in particular thei...

N ov 1 99 6 Some Quantum Aspects of D = 3 Space - Time Massive Gravity

We discuss some features of Einstein-Proca gravity in D = 3 and 4 spacetimes. Our study includes a discussion on the tree-level unitarity and on the issue of light deflection in 3D gravity in the presence of a mass term. 1 [email protected] 2 [email protected]

N ov 2 00 4 On entropic quantities related to the classical capacity of infinite dimensional quantum channels

N ov 2 00 4 Attractions of Affine Quantum Gravity ∗

All attempts to quantize gravity face several difficult problems. Among these problems are: (i) metric positivity (positivity of the spatial distance between distinct points), (ii) the presence of anomalies (partial second-class nature of the quantum constraints), and (iii) perturbative nonrenormalizability (the need for infinitely many distinct counterterms). In this report, a relatively nonte...

ar X iv : q ua nt - p h / 03 11 00 6 v 1 3 N ov 2 00 3 Continuous - variable quantum cryptography is secure against non - gaussian attacks

A general study of arbitrary finite-size coherent attacks against continuous-variable quantum cryptographic schemes is presented. It is shown that, if the size of the blocks that can be coherently attacked by an eavesdropper is fixed and much smaller than the key size, then the optimal attack for a given signal-to-noise ratio in the transmission line is an individual gaussian attack. Consequent...