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Constraints On Vector Unparticle Physics From Cosmic Censorship, Jonas R. Mureika
Constraints On Vector Unparticle Physics From Cosmic Censorship, Jonas R. Mureika
Physics Faculty Works
Vector unparticle couplings to standard model fields produce repulsive corrections to gravity. From a general relativistic perspective, this leads to an effective Reissner-Nordstrom-like metric whose "charge" is a function of the unparticle coupling constant λ, and therefore can admit naked singularities. Requiring the system to respect cosmic censorship provides a new method of constraining the value of λ. These limits are extremely loose for stellar-mass black holes, but commensurate with existing bounds for primordial black holes. In the case of theoretical low-mass black holes, the bounds on λ are much stricter than those derived from astrophysical and accelerator …
(1+1)-Dimensional Entropic Gravity, R. B. Mann, Jonas R. Mureika
(1+1)-Dimensional Entropic Gravity, R. B. Mann, Jonas R. Mureika
Physics Faculty Works
We consider the formulation of entropic gravity in two spacetime dimensions. The usual gravitational force law is derived even in the absence of area, as normally required by the holographic principle. A special feature of this perspective concerns the nature of temperature and entropy defined at a point. We argue that the constancy of the gravitational force in one spatial dimension implies the information contained at each point in space is an internal degree of freedom on the manifold, and furthermore is a universal constant, contrary to previous assertions that entropic gravity in one spatial dimension is ill-defined. We give …
Aspects Of Noncommutative (1+1)-Dimensional Black Holes, Jonas R. Mureika, Piero Nicolini
Aspects Of Noncommutative (1+1)-Dimensional Black Holes, Jonas R. Mureika, Piero Nicolini
Physics Faculty Works
We present a comprehensive analysis of the spacetime structure and thermodynamics of ( 1 + 1 )-dimensional black holes in a noncommutative framework. It is shown that a wider variety of solutions are possible than the commutative case considered previously in the literature. As expected, the introduction of a minimal length √ θ cures singularity pathologies that plague the standard two-dimensional general relativistic case, where the latter solution is recovered at large length scales. Depending on the choice of input parameters (black hole mass M, cosmological constant Λ , etc.), black hole solutions with zero, up to six, horizons …
Detecting Vanishing Dimensions Via Primordial Gravitational Wave Astronomy, Jonas R. Mureika, Dejan Stojkovic
Detecting Vanishing Dimensions Via Primordial Gravitational Wave Astronomy, Jonas R. Mureika, Dejan Stojkovic
Physics Faculty Works
Lower dimensionality at higher energies has manifold theoretical advantages as recently pointed out by Anchordoqui et al. [arXiv:1003.5914]. Moreover, it appears that experimental evidence may already exist for it: A statistically significant planar alignment of events with energies higher than TeV has been observed in some earlier cosmic ray experiments. We propose a robust and independent test for this new paradigm. Since ( 2 + 1 )-dimensional spacetimes have no gravitational degrees of freedom, gravity waves cannot be produced in that epoch. This places a universal maximum frequency at which primordial waves can propagate, marked by the transition between dimensions. …
Kinematical Conformal Cosmology: Fundamental Parameters From Astrophysical Observations, Gabriele U. Varieschi
Kinematical Conformal Cosmology: Fundamental Parameters From Astrophysical Observations, Gabriele U. Varieschi
Physics Faculty Works
No abstract provided.