MG11 
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Gravitational lensing by braneworld black holes (COO2 Theoretical Gravitational Lensing)

We consider several spherically symmetric and static vacuum solutions in the braneworld scenario. The deflection of light in these geometries is modified compared to that in the standard Schwarzschild metric. We first consider the weak-field regime where we derive the deflection angle, Einstein radius, and the magnification produced for a particular braneworld solution. We then discuss strong-field gravitational lensing properties of several braneworld black hole metrics. The position of relativistic images and the corresponding magnification get modified,and we study the impact of braneworld parameters on the lensing observables. The computation of lensing variables enables us to suggest the possibility of the strong field character of gravity being probed and different models being discriminated in future observations. Further, the higher dimensional nature of gravity could itself be revealed, through lensing properties of braneworld black holes.

Dark energy from quantum wave function collapse of dark matter (COT5 Dark Energy and Universe Acceleration)

Dynamical wave function collapse models entail the continuous liberation of a specified rate of energy arising from the interaction of a fluctuating scalar field with the matter wave function. We consider the wave function collapse process for the constituents of dark matter in our universe. Beginning from a particular early era of the universe chosen from physical considerations, the rate of the associated energy liberation is integrated to yield the requisite magnitude of dark energy during the era of galaxy formation. Further, the equation of state for the liberated energy approaches $w \to -1$ at late times, providing a mechanism to generate the present acceleration of the universe. (gr-qc/0506108)

Dark energy from quantum wave function collapse of dark matter

Dynamical wave function collapse models entail the continuous liberation of a specified rate of energy arising from the interaction of a fluctuating scalar field with the matter wave function. We consider the wave function collapse process for the constituents of dark matter in our universe. Beginning from a particular early era of the universe chosen from physical considerations, the rate of the associated energy liberation is integrated to yield the requisite magnitude of dark energy during the era of galaxy formation. Further, the equation of state for the liberated energy approaches $w \to -1$ at late times, providing a mechanism to generate the present acceleration of the universe. (gr-qc/0506108)