Talk detail

Participant	Mottola, Emil
Institution	Los Alamos National Laboratory - Theoretical Division, MS B285 - Los Alamos - NM - USA

Session	AT3	Accepted		Order	Time
Talk	Oral abstract	Title	Gravitational Condensate Stars
Co-authors
Abstract	The proposal of a stable, non-singular ground state for complete gravitational collapse consistent with quantum mechanics, gravitational vacuum condensate stars is reviewed in light of recent developments. Gravastars are cold, dark, compact objects with an interior de Sitter dark energy condensate and an exterior Schwarzschild or Kerr geometry of arbitrary total mass M. They have no singularities, no event horizons, and an entropy of order of typical stellar progenitors proportional to the 3/2 power of M rather than M^2. Unitary time evolution for gravastars is preserved and there is no information paradox. The role of the trace anomaly in generating the quantum fluctuations necessary to form a gravastar will be discussed.

Session	CM4	Accepted		Order	Time
Talk	Oral abstract	Title	Conformal Invariance, Dark Energy and CMB Non-Gaussianity
Co-authors
Abstract	In addition to scale invariance, a universe dominated by dark energy naturally gives rise to correlation functions possessing full conformal invariance. This is due to the mathematical isomorphism between the conformal group of certain three dimensional slices of de Sitter space and the de Sitter isometry group. The embedding of flat spatial sections in de Sitter space induces a conformal invariant perturbation spectrum and definite prediction for the shape of the non-Gaussian CMB bispectrum. In the case in which the density fluctuations are generated instead on the de Sitter horizon, conformal invariance of the horizon embedding implies a different but also quite definite prediction for the angular correlations of CMB non-Gaussianity on the sky. Each of these forms is different from the predictions of single field slow roll inflation models. A quantum origin for the CMB fluctuations in the scalar gravitational sector from the conformal anomaly that could give rise to these non-Gaussianities without a slow roll inflaton field, and conformal invariance also leads to a universal prediction for the equality of scalar and tensor weights and the relation n_S - 1 = n_T between the spectral indices of the scalar and tensor power spectrum. Confirmation of this prediction or detection of non-Gaussian correlations in the CMB can help both to establish the physical origins of primordial density fluctuations, and distinguish between different dynamical models of cosmological vacuum dark energy.

Session	AT2	Accepted		Order	Time
Talk	Oral abstract	Title	Macroscopic Effects of the Conformal Anomaly and the Effective Theory of Gravity
Co-authors
Abstract	General Relativity receives quantum corrections relevant at macroscopic distance scales and near event horizons. These arise from the conformal scalar degrees of freedom in the extended effective field theory of gravity generated by the trace anomaly of massless quantum fields in curved space. The origin of these conformal scalar degrees of freedom as massless poles in two-particle intermediate states of anomalous amplitudes can be seen even in flat space. These are non-local quantum pair correlated states, not present in the classical theory. At event horizons the conformal anomaly scalar degrees of freedom can have macroscopically large effects on the geometry, potentially removing the classical event horizon of black hole and cosmological spacetimes, replacing them with a quantum boundary layer where the effective value of the gravitational vacuum energy density can change. In the effective theory, the cosmological term becomes a dynamical condensate, whose value depends upon boundary conditions. In the conformal phase where the anomaly induced fluctutations dominate, and the condensate dissolves, the effective cosmological "constant" runs with an infrared stable fixed point at zero.