The Experts below are selected from a list of 285 Experts worldwide ranked by ideXlab platform
Lawrence H. Ford - One of the best experts on this subject based on the ideXlab platform.
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General Relativity: An Introduction for Physicists - General Relativity: An Introduction for Physicists
Physics Today, 2007Co-Authors: Lawrence H. FordAbstract:1. The spacetime of special Relativity 2. Manifolds and coordinates 3. Vector calculus on manifolds 4. Tensor calculus on manifolds 5. Special Relativity revisited 6. Electromagnetism 7. The equivalence principle and spacetime curvature 8. The gravitational field equations 9. The Schwarzschild geometry 10. Experimental tests of General Relativity 11. Schwarzschild black holes 12. Further spherically-symmetric geometries 13. The Kerr geometry 14. The Friedmann-Robertson-Walker geometry 15. Cosmological models 16. Inflationary cosmology 17. Linearised General Relativity 18. Gravitational waves 19. A variational approach to General Relativity.
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General Relativity an introduction for physicists
Physics Today, 2006Co-Authors: Lawrence H. FordAbstract:1. The spacetime of special Relativity 2. Manifolds and coordinates 3. Vector calculus on manifolds 4. Tensor calculus on manifolds 5. Special Relativity revisited 6. Electromagnetism 7. The equivalence principle and spacetime curvature 8. The gravitational field equations 9. The Schwarzschild geometry 10. Experimental tests of General Relativity 11. Schwarzschild black holes 12. Further spherically-symmetric geometries 13. The Kerr geometry 14. The Friedmann-Robertson-Walker geometry 15. Cosmological models 16. Inflationary cosmology 17. Linearised General Relativity 18. Gravitational waves 19. A variational approach to General Relativity.
B.p. Abbott - One of the best experts on this subject based on the ideXlab platform.
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tests of General Relativity with gw150914
Physical Review Letters, 2016Co-Authors: B.p. Abbott, T. Adams, R Abbott, T D Abbott, M R Abernathy, F Acernese, K Ackley, C Adams, P Addesso, R X AdhikariAbstract:The LIGO detection of GW150914 provides an unprecedented opportunity to study the two-body motion of a compact-object binary in the large-velocity, highly nonlinear regime, and to witness the final merger of the binary and the excitation of uniquely relativistic modes of the gravitational field. We carry out several investigations to determine whether GW150914 is consistent with a binary black-hole merger in General Relativity. We find that the final remnant’s mass and spin, as determined from the low-frequency (inspiral) and high-frequency (postinspiral) phases of the signal, are mutually consistent with the binary black-hole solution in General Relativity. Furthermore, the data following the peak of GW150914 are consistent with the least-damped quasinormal mode inferred from the mass and spin of the remnant black hole. By using waveform models that allow for parametrized General-Relativity violations during the inspiral and merger phases, we perform quantitative tests on the gravitational-wave phase in the dynamical regime and we determine the first empirical bounds on several high-order post-Newtonian coefficients. We constrain the graviton Compton wavelength, assuming that gravitons are dispersed in vacuum in the same way as particles with mass, obtaining a 90%-confidence lower bound of 1013 km. In conclusion, within our statistical uncertainties, we find no evidence for violations of General Relativity in the genuinely strong-field regime of gravity.
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Tests of General Relativity with GW150914
Physical Review Letters, 2016Co-Authors: B.p. Abbott, T. Adams, R. Bonnand, D. Buskulic, V. Germain, M. Ducrot, R. Gouaty, N. Letendre, F. Marion, A. MasserotAbstract:The LIGO detection of GW150914 provides an unprecedented opportunity to study the two-body motion of a compact-object binary in the large velocity, highly nonlinear regime, and to witness the final merger of the binary and the excitation of uniquely relativistic modes of the gravitational field. We carry out several investigations to determine whether GW150914 is consistent with a binary black-hole merger in General Relativity. We find that the final-remnant's mass and spin, determined from the inspiral and post-inspiral phases of the signal, are mutually consistent with the binary black-hole solution in General Relativity. The data following the peak of GW150914 are consistent with the least-damped quasi-normal-mode inferred from the mass and spin of the remnant black hole. By using waveform models that allow for parameterized General-Relativity violations during the inspiral and merger phases, we perform quantitative tests on the gravitational-wave phase in the dynamical regime and, bound, for the first time several high-order post-Newtonian coefficients. We constrain the graviton Compton wavelength in a hypothetical theory of gravity in which the graviton is massive and place a 90%-confidence lower bound of 1013 km. Within our statistical uncertainties, we find no evidence for violations of General Relativity in the genuinely strong-field regime of gravity.
Thomas Thiemann - One of the best experts on this subject based on the ideXlab platform.
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Modern Canonical Quantum General Relativity
2007Co-Authors: Thomas ThiemannAbstract:This is an introduction to the by now fifteen years old research field of canonical quantum General Relativity, sometimes called "loop quantum gravity". The term "modern" in the title refers to the fact that the quantum theory is based on formulating classical General Relativity as a theory of connections rather than metrics as compared to in original version due to Arnowitt, Deser and Misner. Canonical quantum General Relativity is an attempt to define a mathematically rigorous, non-perturbative, background independent theory of Lorentzian quantum gravity in four spacetime dimensions in the continuum. The approach is minimal in that one simply analyzes the logical consequences of combining the principles of General Relativity with the principles of quantum mechanics. The requirement to preserve background independence has lead to new, fascinating mathematical structures which one does not see in perturbative approaches, e.g. a fundamental discreteness of spacetime seems to be a prediction of the theory providing a first substantial evidence for a theory in which the gravitational field acts as a natural UV cut-off. An effort has been made to provide a self-contained exposition of a restricted amount of material at the appropriate level of rigour which at the same time is accessible to graduate students with only basic knowledge of General Relativity and quantum field theory on Minkowski space
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introduction to modern canonical quantum General Relativity
arXiv: General Relativity and Quantum Cosmology, 2001Co-Authors: Thomas ThiemannAbstract:This is an introduction to the by now fifteen years old research field of canonical quantum General Relativity, sometimes called "loop quantum gravity". The term "modern" in the title refers to the fact that the quantum theory is based on formulating classical General Relativity as a theory of connections rather than metrics as compared to in original version due to Arnowitt, Deser and Misner. Canonical quantum General Relativity is an attempt to define a mathematically rigorous, non-perturbative, background independent theory of Lorentzian quantum gravity in four spacetime dimensions in the continuum. The approach is minimal in that one simply analyzes the logical consequences of combining the principles of General Relativity with the principles of quantum mechanics. The requirement to preserve background independence has lead to new, fascinating mathematical structures which one does not see in perturbative approaches, e.g. a fundamental discreteness of spacetime seems to be a prediction of the theory providing a first substantial evidence for a theory in which the gravitational field acts as a natural UV cut-off. An effort has been made to provide a self-contained exposition of a restricted amount of material at the appropriate level of rigour which at the same time is accessible to graduate students with only basic knowledge of General Relativity and quantum field theory on Minkowski space.
Erik Curiel - One of the best experts on this subject based on the ideXlab platform.
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General Relativity Needs No Interpretation*
Philosophy of Science, 2009Co-Authors: Erik CurielAbstract:I argue that, contrary to the recent claims of physicists and philosophers of physics, General Relativity requires no interpretation in any substantive sense of the term. I canvass the common reasons given in favor of the alleged need for an interpretation, including the difficulty in coming to grips with the physical significance of diffeomorphism invariance and of singular structure, and the problems faced in the search for a theory of quantum gravity. I find that none of them shows any defect in our comprehension of General Relativity as a physical theory. I conclude by comparing General Relativity with quantum mechanics, a theory that manifestly does stand in need of an interpretation in an important sense. Although many aspects of the conceptual structure of General Relativity remain poorly understood, it suffers no incoherence in its formulation as a physical theory that only an ‘interpretation’ could resolve.
Peter Bussey - One of the best experts on this subject based on the ideXlab platform.
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A student’s guide to General Relativity / General Relativity, a concise introduction
Contemporary Physics, 2019Co-Authors: Peter BusseyAbstract:To many students, a course on General Relativity can seem like being led on a path through the jungle. After passing through much tensorial undergrowth, the student arrives at a series of clearings...