1
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Castelvecchi D. Dark energy is tearing the Universe apart. What if the force is weakening? Nature 2024; 629:274-275. [PMID: 38702526 DOI: 10.1038/d41586-024-01273-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2024]
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2
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Castelvecchi D. 'Best view ever': observatory will map Big Bang's afterglow in new detail. Nature 2024; 628:14-15. [PMID: 38519544 DOI: 10.1038/d41586-024-00333-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2024]
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3
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Castelvecchi D. Cosmologist Claudia de Rham on falling for gravity. Nature 2024; 628:30-31. [PMID: 38565656 DOI: 10.1038/d41586-024-00903-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
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4
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Castelvecchi D. Could JWST solve cosmology's big mystery? Physicists debate Universe-expansion data. Nature 2024; 628:697. [PMID: 38627486 DOI: 10.1038/d41586-024-01115-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
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5
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Kulkarni S. How dwarf galaxies lit up the Universe after the Big Bang. Nature 2024:10.1038/d41586-024-00594-8. [PMID: 38418733 DOI: 10.1038/d41586-024-00594-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
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6
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Conroy G. Giant 'bubble' in space could be source of powerful cosmic rays. Nature 2024:10.1038/d41586-024-00574-y. [PMID: 38409403 DOI: 10.1038/d41586-024-00574-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
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7
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Castelvecchi D. This new map of the Universe suggests dark matter shaped the cosmos. Nature 2024:10.1038/d41586-024-00489-8. [PMID: 38356004 DOI: 10.1038/d41586-024-00489-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2024]
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8
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Castelvecchi D. Black-hole observations solve cosmic-ray mystery. Nature 2024; 626:240-241. [PMID: 38297049 DOI: 10.1038/d41586-024-00223-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2024]
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9
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Conroy G. China's new dark-matter lab is biggest and deepest yet. Nature 2024:10.1038/d41586-024-00166-w. [PMID: 38263312 DOI: 10.1038/d41586-024-00166-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
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10
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Shirlow R. Are we part of a unified work of absurd art? Nature 2024; 625:663. [PMID: 38263293 DOI: 10.1038/d41586-024-00187-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
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11
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Chen EK. Does quantum theory imply the entire Universe is preordained? Nature 2023; 624:513-515. [PMID: 38114672 DOI: 10.1038/d41586-023-04024-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
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12
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Khan S, Leghari IU, Pasha AF. Youth Suicide, Supernatural Beings and the Shamanic Response in Hunza: Northern Pakistan. J Relig Health 2023; 62:3760-3779. [PMID: 37955755 DOI: 10.1007/s10943-023-01944-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/26/2023] [Indexed: 11/14/2023]
Abstract
In recent years, Hunza has seen a surge of suicide cases among youth. This paper attempts to decipher the multiple layers of meanings entailed in suicide cases. The dominant perception among the natives is the attribution of influence to supernatural beings. This paper attempts to provide insights into the supernatural cosmology and its relationship to youth suicide among the Burushaski speakers of Hunza. Using qualitative research methodology, this paper describes the local perception of supernatural beings, and their classifications as well as the role of local shamans, known in Burushaski as bitan. In this scenario, suicide is not seen as a self-destruction, but is rather a punishment by the supernatural beings owing to the violation of the sacred supernatural social order imposed by the spirits connected to the supernatural world. For the natives, both the terrestrial and supernatural spheres share common habitats and mountain ecology; however, the latter is perceived to have more powers than the former. Therefore, breach of this order is highly discouraged and bears dire consequences. What appears as mere supernatural and human conflict actually carries deeper references to social and ecological disruptions.
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Affiliation(s)
- Salmaa Khan
- Department of Anthropology, Quaid-I-Azam University, Islamabad, 45320, Pakistan
| | - Inam Ullah Leghari
- Department of Anthropology, Quaid-I-Azam University, Islamabad, 45320, Pakistan.
| | - Adil Farooq Pasha
- Department of Anthropology, Quaid-I-Azam University, Islamabad, 45320, Pakistan
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13
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Currivan J. How an emergent cosmology of a nonlocally unified, meaningfully in-formed and holographically manifested Universe can underpin and frame the biological embodiment of quantum entanglement. Prog Biophys Mol Biol 2023; 185:33-36. [PMID: 37866471 DOI: 10.1016/j.pbiomolbio.2023.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 10/04/2023] [Indexed: 10/24/2023]
Abstract
With a Nobel Prize for Physics widely viewed as only given for 'settled' science, the award then essentially accepts the validity of universal nonlocality. Other key discoveries and insights in recent years are also progressively pointing to the appearance of our Universe, its energy-matter and space-time, as not being foundational but emerging from deeper, discarnate realms of causation. as digitized and meaningful, in-formation, its manifestation pixelated at the so-named Planck scale of existence. Extending from studies of black holes to the entire Universe, a growing number of cosmologists have also developed the so-named holographic principle, to model the four-dimensional appearance of our Universe (three dimensions of space and one of time) as a holographic projection of its two- dimensional boundary. In framing the emergent cosmology of a nonlocally unified, meaningfully in-formed and holographically manifested Universe, an expansion of the three universal Laws of Thermodynamics to three Laws of Information, or Infodynamics also points the way to reconciling Quantum Theory that describes energy-matter and Relativity Theory that describes space-time and offers too an understanding of how the lifecycle of our Universe flows from its first moment until its last. Treating gravity as an emergent consequence of the in-formational and holographic structure of space- time and describing it as the consequence of the intropy associated with the positions in space-time of massive bodies, also points to the findings of the loss of phenotype identity in zero gravity and the role between gravity and cellular identity and the emergence of symbiogenesis.
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Affiliation(s)
- Jude Currivan
- Co-founder WholeWorld-View, 17 Withy Bed, Bushton, Wiltshire, SN4 7QD, UK.
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14
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Conroy G. The most powerful cosmic ray since the Oh-My-God particle puzzles scientists. Nature 2023:10.1038/d41586-023-03677-0. [PMID: 37996738 DOI: 10.1038/d41586-023-03677-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2023]
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15
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'Early dark energy' fails to solve mystery of cosmic expansion. Nature 2023; 623:890. [PMID: 38001274 DOI: 10.1038/d41586-023-03559-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2023]
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16
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Conroy G. This fast radio burst took 8 billion years to reach Earth. Nature 2023:10.1038/d41586-023-03264-3. [PMID: 37857878 DOI: 10.1038/d41586-023-03264-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2023]
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17
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Wenmackers S. Uniform probability in cosmology. Stud Hist Philos Sci 2023; 101:48-60. [PMID: 37690232 DOI: 10.1016/j.shpsa.2023.08.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 07/08/2023] [Accepted: 08/23/2023] [Indexed: 09/12/2023]
Abstract
Problems with uniform probabilities on an infinite support show up in contemporary cosmology. This paper focuses on the context of inflation theory, where it complicates the assignment of a probability measure over pocket universes. The measure problem in cosmology, whereby it seems impossible to pick out a uniquely well-motivated measure, is associated with a paradox that occurs in standard probability theory and crucially involves uniformity on an infinite sample space. This problem has been discussed by physicists, albeit without reference to earlier work on this topic. The aim of this article is both to introduce philosophers of probability to these recent discussions in cosmology and to familiarize physicists and philosophers working on cosmology with relevant foundational work by Kolmogorov, de Finetti, Jaynes, and other probabilists. As such, the main goal is not to solve the measure problem, but to clarify the exact origin of some of the current obstacles. The analysis of the assumptions going into the paradox indicates that there exist multiple ways of dealing consistently with uniform probabilities on infinite sample spaces. Taking a pluralist stance towards the mathematical methods used in cosmology shows there is some room for progress with assigning probabilities in cosmological theories.
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Affiliation(s)
- Sylvia Wenmackers
- Centre for Logic and Philosophy of Science, Institute of Philosophy, KU Leuven, Belgium.
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18
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Duerr PM, Wolf WJ. Methodological reflections on the MOND/dark matter debate. Stud Hist Philos Sci 2023; 101:1-23. [PMID: 37531699 DOI: 10.1016/j.shpsa.2023.07.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 06/28/2023] [Accepted: 07/07/2023] [Indexed: 08/04/2023]
Abstract
The paper re-examines the principal methodological questions, arising in the debate over the cosmological standard model's postulate of Dark Matter vs. rivalling proposals that modify standard (Newtonian and general-relativistic) gravitational theory, the so-called Modified Newtonian Dynamics (MOND) and its subsequent extensions. What to make of such seemingly radical challenges of cosmological orthodoxy? In the first part of our paper, we assess MONDian theories through the lens of key ideas of major 20th century philosophers of science (Popper, Kuhn, Lakatos, and Laudan), thereby rectifying widespread misconceptions and misapplications of these ideas common in the pertinent MOND-related literature. None of these classical methodological frameworks, which render precise and systematise the more intuitive judgements prevalent in the scientific community, yields a favourable verdict on MOND and its successors-contrary to claims in the MOND-related literature by some of these theories' advocates; the respective theory appraisals are largely damning. Drawing on these insights, the paper's second part zooms in on the most common complaint about MONDian theories, their ad-hocness. We demonstrate how the recent coherentist model of ad-hocness captures, and fleshes out, the underlying-but too often insufficiently articulated-hunches underlying this critique. MONDian theories indeed come out as severely ad hoc: they do not cohere well with either theoretical or empirical-factual background knowledge. In fact, as our complementary comparison with the cosmological standard model's Dark Matter postulate shows, with respect to ad-hocness, MONDian theories fare worse than the cosmological standard model.
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Affiliation(s)
- Patrick M Duerr
- Martin Buber Society of Fellows for Research in the Humanities and Social Sciences, Hebrew University of Jerusalem, Israel; Faculty of Philosophy, University of Oxford, UK.
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19
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Castelvecchi D. Japan's space observatory will measure X-rays in exquisite detail. Nature 2023:10.1038/d41586-023-02694-3. [PMID: 37620578 DOI: 10.1038/d41586-023-02694-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/26/2023]
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20
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Thompson B, Bundell S. Even a 'minimal cell' can grow stronger, thanks to evolution. Nature 2023:10.1038/d41586-023-02232-1. [PMID: 37407781 DOI: 10.1038/d41586-023-02232-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/07/2023]
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21
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Goobar A, Johansson J, Schulze S, Arendse N, Carracedo AS, Dhawan S, Mörtsell E, Fremling C, Yan L, Perley D, Sollerman J, Joseph R, Hinds KR, Meynardie W, Andreoni I, Bellm E, Bloom J, Collett TE, Drake A, Graham M, Kasliwal M, Kulkarni SR, Lemon C, Miller AA, Neill JD, Nordin J, Pierel J, Richard J, Riddle R, Rigault M, Rusholme B, Sharma Y, Stein R, Stewart G, Townsend A, Vinko J, Wheeler JC, Wold A. Uncovering a population of gravitational lens galaxies with magnified standard candle SN Zwicky. Nat Astron 2023; 7:1098-1107. [PMID: 37736027 PMCID: PMC10509034 DOI: 10.1038/s41550-023-01981-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 04/24/2023] [Indexed: 09/23/2023]
Abstract
Detecting gravitationally lensed supernovae is among the biggest challenges in astronomy. It involves a combination of two very rare phenomena: catching the transient signal of a stellar explosion in a distant galaxy and observing it through a nearly perfectly aligned foreground galaxy that deflects light towards the observer. Here we describe how high-cadence optical observations with the Zwicky Transient Facility, with its unparalleled large field of view, led to the detection of a multiply imaged type Ia supernova, SN Zwicky, also known as SN 2022qmx. Magnified nearly 25-fold, the system was found thanks to the standard candle nature of type Ia supernovae. High-spatial-resolution imaging with the Keck telescope resolved four images of the supernova with very small angular separation, corresponding to an Einstein radius of only θE = 0.167″ and almost identical arrival times. The small θE and faintness of the lensing galaxy are very unusual, highlighting the importance of supernovae to fully characterize the properties of galaxy-scale gravitational lenses, including the impact of galaxy substructures.
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Affiliation(s)
- Ariel Goobar
- The Oskar Klein Centre, Department of Physics, Stockholm University, AlbaNova University Center, Stockholm, Sweden
| | - Joel Johansson
- The Oskar Klein Centre, Department of Physics, Stockholm University, AlbaNova University Center, Stockholm, Sweden
| | - Steve Schulze
- The Oskar Klein Centre, Department of Physics, Stockholm University, AlbaNova University Center, Stockholm, Sweden
| | - Nikki Arendse
- The Oskar Klein Centre, Department of Physics, Stockholm University, AlbaNova University Center, Stockholm, Sweden
| | - Ana Sagués Carracedo
- The Oskar Klein Centre, Department of Physics, Stockholm University, AlbaNova University Center, Stockholm, Sweden
| | - Suhail Dhawan
- Institute of Astronomy and Kavli Institute for Cosmology, University of Cambridge, Cambridge, UK
| | - Edvard Mörtsell
- The Oskar Klein Centre, Department of Physics, Stockholm University, AlbaNova University Center, Stockholm, Sweden
| | - Christoffer Fremling
- Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA USA
| | - Lin Yan
- Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA USA
| | - Daniel Perley
- Astrophysics Research Institute, Liverpool John Moores University, Liverpool, UK
| | - Jesper Sollerman
- The Oskar Klein Centre, Department of Astronomy, Stockholm University, AlbaNova University Center, Stockholm, Sweden
| | - Rémy Joseph
- The Oskar Klein Centre, Department of Physics, Stockholm University, AlbaNova University Center, Stockholm, Sweden
| | - K-Ryan Hinds
- Astrophysics Research Institute, Liverpool John Moores University, Liverpool, UK
| | - William Meynardie
- Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA USA
| | - Igor Andreoni
- Joint Space-Science Institute, University of Maryland, College Park, MD USA
- Department of Astronomy, University of Maryland, College Park, MD USA
- Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD USA
| | - Eric Bellm
- DIRAC Institute, Department of Astronomy, University of Washington, Seattle, WA USA
| | - Josh Bloom
- Department of Astronomy, University of California, Berkeley, CA USA
| | - Thomas E. Collett
- Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth, UK
| | - Andrew Drake
- Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA USA
| | - Matthew Graham
- Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA USA
| | - Mansi Kasliwal
- Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA USA
| | - Shri R. Kulkarni
- Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA USA
| | - Cameron Lemon
- Institute of Physics, Laboratoire d’Astrophysique, Ecole Polytechnique Fédérale de Lausanne (EPFL), Observatoire de Sauverny, Versoix, CH Switzerland
| | - Adam A. Miller
- Department of Physics and Astronomy, Northwestern University, Evanston, IL USA
- Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA), Northwestern University, Evanston, IL USA
| | - James D. Neill
- Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA USA
| | - Jakob Nordin
- Institut fur Physik, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Justin Pierel
- Space Telescope Science Institute, Baltimore, MD USA
| | - Johan Richard
- Université Lyon 1, ENS de Lyon, CNRS, Centre de Recherche Astrophysique de Lyon UMR5574, Saint-Genis-Laval, France
| | - Reed Riddle
- Caltech Optical Observatories, California Institute of Technology, Pasadena, CA USA
| | - Mickael Rigault
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS/IN2P3, IP2I Lyon, Villeurbanne, France
| | - Ben Rusholme
- IPAC, California Institute of Technology, Pasadena, CA USA
| | - Yashvi Sharma
- Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA USA
| | - Robert Stein
- Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA USA
| | | | - Alice Townsend
- Institut fur Physik, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Jozsef Vinko
- Department of Astronomy, University of Texas at Austin, Austin, TX USA
- CSFK, Konkoly Observatory, Budapest, Hungary
| | - J. Craig Wheeler
- Department of Astronomy, University of Texas at Austin, Austin, TX USA
| | - Avery Wold
- IPAC, California Institute of Technology, Pasadena, CA USA
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Boylan-Kolchin M. Stress testing ΛCDM with high-redshift galaxy candidates. Nat Astron 2023; 7:731-735. [PMID: 37351007 PMCID: PMC10281863 DOI: 10.1038/s41550-023-01937-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 03/07/2023] [Indexed: 06/24/2023]
Abstract
Early data from the James Webb Space Telescope (JWST) have revealed a bevy of high-redshift galaxy candidates with unexpectedly high stellar masses. An immediate concern is the consistency of these candidates with galaxy formation in the standard ΛCDM cosmological model, wherein the stellar mass (M⋆) of a galaxy is limited by the available baryonic reservoir of its host dark matter halo. The mass function of dark matter haloes therefore imposes an absolute upper limit on the number density n (>M⋆, z) and stellar mass density ρ⋆ (>M⋆, z) of galaxies more massive than M⋆ at any epoch z. Here I show that the most massive galaxy candidates in JWST observations at z ≈ 7-10 lie at the very edge of these limits, indicating an important unresolved issue with the properties of galaxies derived from the observations, how galaxies form at early times in ΛCDM or within this standard cosmology itself.
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23
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Crease RP. How Stephen Hawking flip-flopped on whether the Universe has a beginning. Nature 2023; 616:243-244. [PMID: 37037933 DOI: 10.1038/d41586-023-00977-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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24
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Clues to the assembly of an infant galaxy cluster. Nature 2023. [PMID: 36991047 DOI: 10.1038/d41586-023-00875-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
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25
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Gibney E. Astrophysicists turn fast radio bursts into cosmic probes. Nature 2023:10.1038/d41586-023-00246-3. [PMID: 36707712 DOI: 10.1038/d41586-023-00246-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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26
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Snapshots capture the early stages of a distant stellar explosion. Nature 2022. [PMID: 36352105 DOI: 10.1038/d41586-022-03330-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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27
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Durrer R. Testing general relativity with cosmological large scale structure. Gen Relativ Gravit 2022; 54:88. [PMID: 35996424 PMCID: PMC9388425 DOI: 10.1007/s10714-022-02966-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 07/25/2022] [Indexed: 06/15/2023]
Abstract
In this paper I investigate the possibility to test Einstein's equations with observations of cosmological large scale structure. I first show that we have not tested the equations in observations concerning only the homogeneous and isotropic Universe. I then show with several examples how we can do better when considering the fluctuations of both, the energy momentum tensor and the metric. This is illustrated with galaxy number counts, intensity mapping and cosmic shear, three examples that are by no means exhaustive.
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Affiliation(s)
- Ruth Durrer
- Department of Theoretical Physics, Université de Genève, Quai E. Ansermet 24, 1211 Genève, Switzerland
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28
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Castelvecchi D. Mega-map of Milky Way adds depth to stars' motions. Nature 2022:10.1038/d41586-022-01660-9. [PMID: 35697765 DOI: 10.1038/d41586-022-01660-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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29
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Fajman D, Urban L. Blow-up of waves on singular spacetimes with generic spatial metrics. Lett Math Phys 2022; 112:42. [PMID: 35535348 PMCID: PMC9023426 DOI: 10.1007/s11005-022-01522-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 02/11/2022] [Accepted: 02/17/2022] [Indexed: 06/14/2023]
Abstract
We study the asymptotic behaviour of solutions to the linear wave equation on cosmological spacetimes with Big Bang singularities and show that appropriately rescaled waves converge against a blow-up profile. Our class of spacetimes includes Friedman-Lemaître-Robertson-Walker (FLRW) spacetimes with negative sectional curvature that solve the Einstein equations in the presence of a perfect irrotational fluid with p = ( γ - 1 ) ρ . As such, these results are closely related to the still open problem of past nonlinear stability of such FLRW spacetimes within the Einstein scalar field equations. In contrast to earlier works, our results hold for spatial metrics of arbitrary geometry, hence indicating that the matter blow-up in the aforementioned problem is not dependent on spatial geometry. Additionally, we use the energy estimates derived in the proof in order to formulate open conditions on the initial data that ensure a non-trivial blow-up profile, for initial data sufficiently close to the Big Bang singularity and with less harsh assumptions for γ < 2 .
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Affiliation(s)
- David Fajman
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Liam Urban
- Faculty of Mathematics, University of Vienna, Oskar-Morgenstern-Platz 1, 1090 Vienna, Austria
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Castelvecchi D. Did astronomers see hints of first stars? Experiment casts doubt on bold claim. Nature 2022:10.1038/d41586-022-00577-7. [PMID: 35228734 DOI: 10.1038/d41586-022-00577-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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31
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Leconte-Chevillard G. Experimentation in the cosmic laboratory. Stud Hist Philos Sci 2021; 90:265-274. [PMID: 34753068 DOI: 10.1016/j.shpsa.2021.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 09/24/2021] [Accepted: 10/08/2021] [Indexed: 06/13/2023]
Abstract
It might seem impossible to apply Ian Hacking's experimental argument for scientific realism to astrophysical objects; indeed Hacking himself expressed scepticism about extragalactic entities. Such astrophysical antirealism has been the subject of intense debate and is usually seen as an undesired consequence of experimental realism. In this paper, I claim that it is possible to recast the experimental argument by reference to James Woodward's non-anthropocentric account of experimentation so as to apply it to astrophysical entities, such as gravitational lenses. I also argue that this new formulation of the experimental argument solves several problems with Hacking's original version.
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Affiliation(s)
- Gauvain Leconte-Chevillard
- Institut d'Histoire et de Philosophie des Sciences et des Techniques, 13 rue du Four, 75006, Paris, France.
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32
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Castelvecchi D. Astrophysicists unveil glut of gravitational-wave detections. Nature 2021:10.1038/d41586-021-03089-y. [PMID: 34754103 DOI: 10.1038/d41586-021-03089-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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33
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Fijn N, Terbish B. The Multiple Faces of the Marmot: Associations with the Plague, Hunting, and Cosmology in Mongolia. Hum Ecol Interdiscip J 2021; 49:539-549. [PMID: 34658483 PMCID: PMC8513552 DOI: 10.1007/s10745-021-00264-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 08/31/2021] [Indexed: 06/13/2023]
Abstract
Mongolians have long known of the association between marmots and the plague. We examine their understanding of the marmot not only as a biological species that can harbour the plague, but also from a cosmological perspective as a chimerical being with potential punishment on hunters who have transgressed ancient taboos. To do so we deconstruct the multiple image of the chimerical marmot in legends, stories, and beliefs. Many Mongolians believe that if the marmot is over-exploited and the population decimated through excessive hunting, hunting households may be punished with infections of the plague.
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Affiliation(s)
- Natasha Fijn
- The Mongolia Institute, College of Asia and the Pacific, The Australian National University, Canberra, Australia
| | - Baasanjav Terbish
- Mongolia Inner Asia Studies Unit, University of Cambridge, Cambridge, England
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34
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Cinti E, Fano V. Careful with those scissors, Eugene! Against the observational indistinguishability of spacetimes. Stud Hist Philos Sci 2021; 89:103-113. [PMID: 34418638 DOI: 10.1016/j.shpsa.2021.07.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 07/08/2021] [Accepted: 07/13/2021] [Indexed: 06/13/2023]
Abstract
We discuss Manchak (2009a)'s result that there are locally (but not globally) isometric universes observationally indistinguishable from our own. This theorem makes the epistemic predicament of modern cosmology particularly problematic and the prospects of ever gaining knowledge of the global structure of the universe rather unlikely in the context of general relativity. We argue however that this conclusion is too quick; indeed, Manchak's theorem deploys spacetimes which are not physically reasonable, since they have features which are not the product of any physical process. This ultimately rests on the fact that local isometry between two spacetimes is not sufficient to guarantee that they are both physically reasonable. We propose an additional condition to properly define when a spacetime is physically reasonable, and we show that Manchak's spacetimes do not satisfy this further demand.
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Affiliation(s)
- Enrico Cinti
- University of Urbino, DISPeA, Via Timoteo Viti 10, 61029, Urbino PU, Italy; Department of Philosophy, University of Geneva, rue de Candolle 5, CH-1211, Genève 4, Switzerland.
| | - Vincenzo Fano
- University of Urbino, DISPeA, Via Timoteo Viti 10, 61029, Urbino PU, Italy.
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35
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Castelvecchi D. New type of dark energy could solve Universe expansion mystery. Nature 2021; 597:460-1. [PMID: 34535779 DOI: 10.1038/d41586-021-02531-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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36
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Merritt D. Cosmological realism. Stud Hist Philos Sci 2021; 88:193-208. [PMID: 34218160 DOI: 10.1016/j.shpsa.2021.05.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 05/26/2021] [Accepted: 05/27/2021] [Indexed: 06/13/2023]
Abstract
I discuss the relevance of the current predicament in cosmology to the debate over scientific realism. I argue that the existence of two, empirically successful but ontologically inconsistent cosmological theories presents difficulties for the realist position.
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37
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McGaugh SS. Testing galaxy formation and dark matter with low surface brightness galaxies. Stud Hist Philos Sci 2021; 88:220-236. [PMID: 34224943 DOI: 10.1016/j.shpsa.2021.05.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/26/2021] [Accepted: 05/26/2021] [Indexed: 06/13/2023]
Abstract
Galaxies are the basic structural element of the universe; galaxy formation theory seeks to explain how these structures came to be. I trace some of the foundational ideas in galaxy formation, with emphasis on the need for non-baryonic cold dark matter. Many elements of early theory did not survive contact with observations of low surface brightness galaxies, leading to the need for auxiliary hypotheses like feedback. The failure points often trace to the surprising predictive successes of an alternative to dark matter, the Modified Newtonian Dynamics (MOND). While dark matter models are flexible in accommodating observations, they do not provide the predictive capacity of MOND. If the universe is made of cold dark matter, why does MOND get any predictions right?
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Affiliation(s)
- Stacy S McGaugh
- Department of Astronomy, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH, 44106, USA.
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38
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Castelvecchi D. Mysterious fast radio bursts come in two distinct flavours. Nature 2021:10.1038/d41586-021-01560-4. [PMID: 34113028 DOI: 10.1038/d41586-021-01560-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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39
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Castelvecchi D. The most detailed 3D map of the Universe ever made. Nature 2021:10.1038/d41586-021-01466-1. [PMID: 34050347 DOI: 10.1038/d41586-021-01466-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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40
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Hui Y. This Strange Being Called the Cosmos. Found Sci 2021; 27:1409-1414. [PMID: 33824616 PMCID: PMC8015925 DOI: 10.1007/s10699-020-09740-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/10/2020] [Indexed: 06/12/2023]
Abstract
This supplementary essay aims to respond to and clarify the misunderstandings concerning the concept of cosmotechnics, the ambiguities of the term cosmos arisen in the article "For a Cosmotechnical Event," as well as the reason for the neologism of cosmotechnics.
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Affiliation(s)
- Yuk Hui
- School of Creative Media, City University of Hong Kong, Hong Kong, China
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41
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Howe N, Bundell S. When did people arrive in the Americas? New evidence stokes debate. Nature 2020:10.1038/d41586-020-02200-z. [PMID: 34290410 DOI: 10.1038/d41586-020-02200-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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43
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Zeyauddin M, Zia R, Rao CV. Anisotropic bianchi V cosmological model in Scale Covariant Theory of Gravitation with a time-variable deceleration parameter. Heliyon 2020; 6:e03676. [PMID: 32258498 PMCID: PMC7113631 DOI: 10.1016/j.heliyon.2020.e03676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 10/26/2019] [Accepted: 03/24/2020] [Indexed: 11/29/2022] Open
Abstract
In this paper we solve the field equations for Scale covariant theory of gravitation which was introduced by Caunato et al. [1], for Bianchi V line element in the presence of perfect fluid medium. Here the deceleration parameter is considered to be time dependent which gives the average scale factor a ( t ) = [ sinh ( β t ) ] 1 / n , where n and β are positive constants. This value of average scale factor is the key expression for solving the field equations. Using the recent observational value of q 0 = - 0.52 - 0.04 + 0.08 and H 0 = 69.2 ± 1.2 derived from BAO/CMB and H(z) data by Santos et al. (2016) [46], we have evaluated three different pairs of ( n , β ) . We observe that the model represents a phase transition from early deceleration to a present accelerating phase for a particular choice of the pair ( n = 2 , β = 92.75 ) . Applying some recently developed diagnostic tools like jerk parameter and statefinders, we find that the derived model is exactly in accordance with standard ΛCDM model. Along with these, many physical, geometric and kinematic properties of the model are thoroughly studied and found consistent with recent observations.
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Affiliation(s)
- Mohammad Zeyauddin
- Department of General Studies (Mathematics), Jubail Industrial College, Jubail Industrial City, Jubail, 31961, Saudi Arabia
| | - Rashid Zia
- Department of Mathematics, Ewing Christian College, Allahabad, Uttar Pradesh, 211003, India
| | - C V Rao
- Department of General Studies (Mathematics), Jubail Industrial College, Jubail Industrial City, Jubail, 31961, Saudi Arabia
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Abstract
This study proposes an axisymmetric generalization of the Vaidya metric, namely the Vaidya–Kerr metric, to describe a radiating rotating black hole, and presents its Hawking radiation temperature. This study is an improved version of our previous research via ellipsoid coordinate transformation, and the Einstein field equations are solved concisely and intuitively by an orthogonal ansatz. The results demonstrate that the energy–momentum tensor of the derived radiating Kerr metric satisfies the energy-conservation law and is classified as a Petrov type II fluid, whereas the stationary Kerr metric is a Petrov type IV vacuum. The inner and outer event-horizon radii, the ergosphere radii, as well as the angular velocity at the event horizon are solved, and then, surface gravity, entropy, and Hawking radiation are derived. We estimate the Hawking-radiation temperature of the black holes with the angular momentum and the same mass of Pluto and the sun, as well as the supermassive black hole in the core of the M87 galaxy to be 9.42K, 6.08×10−8K, and 8.78×10−18K, respectively. Only the value of the rotating Pluto-mass black hole is slightly greater than the 3K cosmic microwave background radiation and may be detected by high-resolution tools in the future.
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45
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46
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Bundell S. The history of the Universe in the blink of an eye. Nature 2019:10.1038/d41586-019-02459-x. [PMID: 32788694 DOI: 10.1038/d41586-019-02459-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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47
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Cyranoski D. China's mountain observatory begins hunt for origins of cosmic rays. Nature 2019:10.1038/d41586-019-01467-1. [PMID: 32376923 DOI: 10.1038/d41586-019-01467-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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49
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Fernandes A, Amorim R, Capistrano A, Ulhoa S. Towards energy discretization in quantum cosmology. Heliyon 2019; 5:e01725. [PMID: 31193441 PMCID: PMC6530654 DOI: 10.1016/j.heliyon.2019.e01725] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 02/13/2019] [Accepted: 05/09/2019] [Indexed: 11/20/2022] Open
Abstract
In this article we presented an application of the quantum cosmological model in teleparallel gravity. Working with a vacuum solution, the gravitational energy density is quantized with the Weyl procedure and we obtain a discrete expression for the gravitational energy. As an immediate consequence the empty space exhibits an expansion for an early universe.
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Affiliation(s)
- A.S. Fernandes
- Instituto de Física, Universidade de Brasília, 70910-900, Brasília, DF, Brazil
| | - R.G.G. Amorim
- Faculdade Gama, Universidade de Brasília, 72444-240, Setor Leste (Gama), Brasília, DF, Brazil
| | - A.J.S. Capistrano
- Federal University of Latin-America Integration, Itaipu Technological Park, PO Box 2123, Foz do Iguaçu-PR, 85867-670, Brazil
| | - S.C. Ulhoa
- International Center of Physics and Instituto de Física, Universidade de Brasília, 70.910-900, Brasilia, DF, Brazil
- Corresponding author.
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50
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Naidu R, Aditya Y, Reddy D. Bianchi type-V dark energy cosmological model in general relativity in the presence of massive scalar field. Heliyon 2019; 5:e01645. [PMID: 31192992 PMCID: PMC6512874 DOI: 10.1016/j.heliyon.2019.e01645] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 04/05/2019] [Accepted: 05/01/2019] [Indexed: 11/28/2022] Open
Abstract
In this paper, we discuss spatially homogeneous and anisotropic Bianchi type-V dark energy cosmological model in the presence of an attractive massive scalar field in general relativity. We have solved the field equations using (i) the shear scalar of the metric is proportional to the expansion scalar which results a relationship between metric potentials and (ii) a power law between the massive scalar field and the average scale factor. We have computed the cosmological parameters like dark energy density, equation of state parameter, skewness parameters, deceleration parameter and statefinder parameters of our dark energy model with massive strings and discussed their physical significance in the light of the recent scenario of accelerated expansion of the universe and cosmological observations.
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Affiliation(s)
- R.L. Naidu
- Department Mathematics, GMR Institute of Technology, Rajam, 532 127, India
| | - Y. Aditya
- Department of Mathematics, ANITS (A), Visakhapatnam, 531162, India
| | - D.R.K. Reddy
- Department of Applied Mathematics, Andhra University, Visakhapatnam, 530003, India
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