AI Article Synopsis
- Recent advances in massive gravity are discussed, highlighting how various theories stem from higher-dimensional general relativity, including the Dvali-Gabadadze-Porrati (DGP) model.
- The text analyzes the consistency of these theories, ensuring they do not have Boulware-Deser ghosts and reviews mechanisms like Vainshtein and cosmological solutions.
- It also introduces alternative models of massive gravity, including new massive gravity, Lorentz-violating massive gravity, and non-local massive gravity.
Article Abstract
We review recent progress in massive gravity. We start by showing how different theories of massive gravity emerge from a higher-dimensional theory of general relativity, leading to the Dvali-Gabadadze-Porrati model (DGP), cascading gravity, and ghost-free massive gravity. We then explore their theoretical and phenomenological consistency, proving the absence of Boulware-Deser ghosts and reviewing the Vainshtein mechanism and the cosmological solutions in these models. Finally, we present alternative and related models of massive gravity such as new massive gravity, Lorentz-violating massive gravity and non-local massive gravity.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5256007 | PMC |
| http://dx.doi.org/10.12942/lrr-2014-7 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Preferential occurrence of fast radio bursts in massive star-forming galaxies.
Nature
November 2024
Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA, USA.
Fast radio bursts (FRBs) are millisecond-duration events detected from beyond the Milky Way. FRB emission characteristics favour highly magnetized neutron stars, or magnetars, as the sources, as evidenced by FRB-like bursts from a galactic magnetar, and the star-forming nature of FRB host galaxies. However, the processes that produce FRB sources remain unknown.
View Article and Find Full Text PDFImprints of massive black-hole binaries on neighbouring decihertz gravitational-wave sources.
Nat Astron
August 2024
Center for Theoretical Astrophysics and Cosmology, Institute for Computational Science, University of Zurich, Zurich, Switzerland.
The most massive black holes in our Universe form binaries at the centre of merging galaxies. The recent evidence for a gravitational-wave (GW) background from pulsar timing may constitute the first observation that these supermassive black-hole binaries (SMBHBs) merge. Yet, the most massive SMBHBs are out of reach of interferometric GW detectors and are exceedingly difficult to resolve individually with pulsar timing.
View Article and Find Full Text PDFThe cool brown dwarf Gliese 229 B is a close binary.
Nature
October 2024
European Southern Observatory, Garching, Germany.
Article Synopsis
- Brown dwarf companions to stars help us understand planet formation processes, but some of them are more massive than expected based on their luminosities and host star ages.
- Gliese 229 B, previously thought to be a single entity, was revealed through observations to actually be two brown dwarfs, Gliese 229 Ba and Bb, with masses of 38.1 and 34.4 Jupiter masses, respectively.
- This discovery challenges existing theories and raises questions about the formation and occurrence of binary brown dwarfs in close orbits around stars.
Prescription for health-care social work - labor unions.
Soc Work Health Care
December 2024
Swedish Medical Center, Seattle, Washington, USA.
Transformations in health care and attendant social work responses have eroded a health-care social work role grounded in holism and social justice. Tracing events at the intersection of social work, the labor movement, and health-care provision, this paper examines the evolution of social work's gravitation to micro-level practice and professionalism at the expense of macro practice, including labor organizing. It argues that engagement between health-care social work and labor unions is mutually beneficial and indispensable in preserving a role that reflects social work values in the face of massive socioeconomic inequality and health-care corporatization.
View Article and Find Full Text PDFCompton Amplitude for Rotating Black Hole from QFT.
Phys Rev Lett
August 2024
Service de Physique de l'Univers, Champs et Gravitation, Université de Mons, 20 place du Parc, 7000 Mons, Belgium.
Article Synopsis
- The article presents a new gravitational Compton amplitude for rotating Kerr black holes applicable to any quantum spin, from zero to infinity.
- It utilizes concepts from higher-spin quantum field theory, such as gauge invariance, to derive classical amplitudes with respect to the spin vector.
- The study emphasizes using a chiral-field approach for clarity in degrees of freedom and simplifies interactions, allowing for comparisons with existing general-relativity results up to eighth order in spin.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!