Shadows and thin accretion disk images of the $$\gamma $$ γ -metric
Abstract The $$\gamma $$ γ -metric is a static, axially-symmetric singular solution of the vacuum Einstein’s equations without an event horizon. This is a two-parameter family of solutions, generic values of one of which (called $$\gamma $$ γ ) measure the deviation from spherical symmetry. We show...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
SpringerOpen
2022-08-01
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| Series: | European Physical Journal C: Particles and Fields |
| Online Access: | https://doi.org/10.1140/epjc/s10052-022-10664-8 |
| _version_ | 1811215500021071872 |
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| author | Rajibul Shaikh Suvankar Paul Pritam Banerjee Tapobrata Sarkar |
| author_facet | Rajibul Shaikh Suvankar Paul Pritam Banerjee Tapobrata Sarkar |
| author_sort | Rajibul Shaikh |
| collection | DOAJ |
| description | Abstract The $$\gamma $$ γ -metric is a static, axially-symmetric singular solution of the vacuum Einstein’s equations without an event horizon. This is a two-parameter family of solutions, generic values of one of which (called $$\gamma $$ γ ) measure the deviation from spherical symmetry. We show that this can serve as a black hole mimicker, consistent with current observations. To this end, we first study the shadow cast by this geometry, in order to constrain the $$\gamma $$ γ -metric from observations. We find that for $$\gamma < 1/2$$ γ < 1 / 2 , there are, in principle, no shadows cast. On the other hand, shadows cast for all values of $$\gamma \ge 1/2$$ γ ≥ 1 / 2 are consistent with observations of M $$87^*$$ 87 ∗ by the Event Horizon Telescope. We also study images of thin accretion disks in the $$\gamma $$ γ -metric background. In situations where the $$\gamma $$ γ -metric possesses light rings, these qualitatively mimic Schwarzschild black holes with the same ADM mass, while in the absence of such rings, they are drastically different from the black hole case. |
| first_indexed | 2024-04-12T06:23:38Z |
| format | Article |
| id | doaj.art-50cbacead927424e9bd9dc913faf0ccb |
| institution | Directory Open Access Journal |
| issn | 1434-6052 |
| language | English |
| last_indexed | 2024-04-12T06:23:38Z |
| publishDate | 2022-08-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | European Physical Journal C: Particles and Fields |
| spelling | doaj.art-50cbacead927424e9bd9dc913faf0ccb2022-12-22T03:44:13ZengSpringerOpenEuropean Physical Journal C: Particles and Fields1434-60522022-08-0182811110.1140/epjc/s10052-022-10664-8Shadows and thin accretion disk images of the $$\gamma $$ γ -metricRajibul Shaikh0Suvankar Paul1Pritam Banerjee2Tapobrata Sarkar3Department of Physics, Indian Institute of TechnologyDepartment of Physics, Indian Institute of TechnologyDepartment of Physics, Indian Institute of TechnologyDepartment of Physics, Indian Institute of TechnologyAbstract The $$\gamma $$ γ -metric is a static, axially-symmetric singular solution of the vacuum Einstein’s equations without an event horizon. This is a two-parameter family of solutions, generic values of one of which (called $$\gamma $$ γ ) measure the deviation from spherical symmetry. We show that this can serve as a black hole mimicker, consistent with current observations. To this end, we first study the shadow cast by this geometry, in order to constrain the $$\gamma $$ γ -metric from observations. We find that for $$\gamma < 1/2$$ γ < 1 / 2 , there are, in principle, no shadows cast. On the other hand, shadows cast for all values of $$\gamma \ge 1/2$$ γ ≥ 1 / 2 are consistent with observations of M $$87^*$$ 87 ∗ by the Event Horizon Telescope. We also study images of thin accretion disks in the $$\gamma $$ γ -metric background. In situations where the $$\gamma $$ γ -metric possesses light rings, these qualitatively mimic Schwarzschild black holes with the same ADM mass, while in the absence of such rings, they are drastically different from the black hole case.https://doi.org/10.1140/epjc/s10052-022-10664-8 |
| spellingShingle | Rajibul Shaikh Suvankar Paul Pritam Banerjee Tapobrata Sarkar Shadows and thin accretion disk images of the $$\gamma $$ γ -metric European Physical Journal C: Particles and Fields |
| title | Shadows and thin accretion disk images of the $$\gamma $$ γ -metric |
| title_full | Shadows and thin accretion disk images of the $$\gamma $$ γ -metric |
| title_fullStr | Shadows and thin accretion disk images of the $$\gamma $$ γ -metric |
| title_full_unstemmed | Shadows and thin accretion disk images of the $$\gamma $$ γ -metric |
| title_short | Shadows and thin accretion disk images of the $$\gamma $$ γ -metric |
| title_sort | shadows and thin accretion disk images of the gamma γ metric |
| url | https://doi.org/10.1140/epjc/s10052-022-10664-8 |
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