60,014 research outputs found
The Horizon Energy of a Black Hole
We investigate the energy distribution of a black hole in various spacetimes
as reckoned by a distant observer using the quasi-local energy approach. In
each case the horizon mass of a black hole: neutral, charged or rotating, is
found to be twice the irreducible mass observed at infinity. This is known as
the Horizon Mass Theorem. As a consequence, the electrostatic energy and the
rotational energy of a general black hole are all external quantities. Matter
carrying charges and spins could only lie outside the horizon. This result
could resolve several long-standing paradoxes related to known black hole
properties; such as why entropy is proportional to area and not to volume, the
information loss problem, the firewall problem, the internal structure and the
thin shell model of a black hole.Comment: Contributed paper to the Fourteenth Marcel Grossmann Meeting on
General Relativity, University of Rome "La Sapienza", Italy, 12 - 18 July
2015 (7 pages) arXiv admin note: text overlap with arXiv:1706.0176
Is There Unification in the 21st Century?
In the last 100 years, the most important equations in physics are Maxwell's
equations for electrodynamics, Einstein's equation for gravity, Dirac's
equation for the electron and Yang-Mills equation for elementary particles. Do
these equations follow a common principle and come from a single theory?
Despite intensive efforts to unify gravity and the particle interactions in the
last 30 years, the goal is still to be achieved. Recent theories have not
answered any question in physics. We examine the issues involved in this long
quest to understand the ultimate nature of spacetime and matter.Comment: Lecture delievered in Conference in Honor of Murray Gell-Mann's 80th
Birthday. February 24 - 26, 2010. Nanyang Executive Centre, Singapore. 10
page
An Underlying Theory for Gravity
A new direction to understand gravity has recently been explored by
considering classical gravity to be a derived interaction from an underlying
theory. This underlying theory would involve new degrees of freedom at a deeper
level and it would be structurally different from classical gravitation. It may
conceivably be a quantum theory or a non-quantum theory. The relation between
this underlying theory and Einstein's gravity is similar to the connection
between statistical mechanics and thermodynamics. We discuss the apparent lack
of evidence of any quantum nature of gravity in this context.Comment: Contributed paper to VIIth International Conference on Gravitation
and Cosmology, 14 - 19 December, 2011 GOA, INDIA. 4 page
Are Black Holes Elementary Particles?
Quantum black holes are the smallest and heaviest conceivable elementary
particles. They have a microscopic size but a macroscopic mass. Several
fundamental types have been constructed with some remarkable properties.
Quantum black holes in the neighborhood of the Galaxy could resolve the paradox
of ultra-high energy cosmic rays detected in Earth's atmosphere. They may also
play a role as dark matter in cosmology.Comment: Lecture delivered in Conference on Particle Physics, Astrophysics and
Quantum Field Theory: 75 Years since Solvay, 27 -29 November 2008, Nanyang
Executive Centre, Singapore. 10 page
A Test of Separability and Random Effects in Production Function with Decomposed IT Capital
Separability Test, IT-using Effect, Panel Regression
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