Kundt geometries and memory effects in the Brans–Dicke theory of gravity
Abstract Memory effects are studied in the simplest scalar–tensor theory, the Brans–Dicke (BD) theory. To this end, we introduce, in BD theory, novel Kundt spacetimes (without and with gyratonic terms), which serve as backgrounds for the ensuing analysis on memory. The BD parameter $$\omega $$ ω and...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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SpringerOpen
2021-04-01
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| Series: | European Physical Journal C: Particles and Fields |
| Online Access: | https://doi.org/10.1140/epjc/s10052-021-09118-4 |
| _version_ | 1818827655199326208 |
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| author | Siddhant Siddhant Indranil Chakraborty Sayan Kar |
| author_facet | Siddhant Siddhant Indranil Chakraborty Sayan Kar |
| author_sort | Siddhant Siddhant |
| collection | DOAJ |
| description | Abstract Memory effects are studied in the simplest scalar–tensor theory, the Brans–Dicke (BD) theory. To this end, we introduce, in BD theory, novel Kundt spacetimes (without and with gyratonic terms), which serve as backgrounds for the ensuing analysis on memory. The BD parameter $$\omega $$ ω and the scalar field ( $$\phi $$ ϕ ) profile, expectedly, distinguishes between different solutions. Choosing specific localised forms for the free metric functions $$H'(u)$$ H ′ ( u ) (related to the wave profile) and J(u) (the gyraton) we obtain displacement memory effects using both geodesics and geodesic deviation. An interesting and easy-to-understand exactly solvable case arises when $$\omega =-2$$ ω = - 2 (with J(u) absent) which we discuss in detail. For other $$\omega $$ ω (in the presence of J or without), numerically obtained geodesics lead to results on displacement memory which appear to match qualitatively with those found from a deviation analysis. Thus, the issue of how memory effects in BD theory may arise and also differ from their GR counterparts, is now partially addressed, at least theoretically, within the context of this new class of Kundt geometries. |
| first_indexed | 2024-12-19T00:47:00Z |
| format | Article |
| id | doaj.art-24b8cb9a2a95459dbd9718bfcfd80293 |
| institution | Directory Open Access Journal |
| issn | 1434-6044 1434-6052 |
| language | English |
| last_indexed | 2024-12-19T00:47:00Z |
| publishDate | 2021-04-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | European Physical Journal C: Particles and Fields |
| spelling | doaj.art-24b8cb9a2a95459dbd9718bfcfd802932022-12-21T20:44:13ZengSpringerOpenEuropean Physical Journal C: Particles and Fields1434-60441434-60522021-04-0181411610.1140/epjc/s10052-021-09118-4Kundt geometries and memory effects in the Brans–Dicke theory of gravitySiddhant Siddhant0Indranil Chakraborty1Sayan Kar2Department of Physics, Indian Institute of Technology KharagpurDepartment of Physics, Indian Institute of Technology KharagpurDepartment of Physics, Indian Institute of Technology KharagpurAbstract Memory effects are studied in the simplest scalar–tensor theory, the Brans–Dicke (BD) theory. To this end, we introduce, in BD theory, novel Kundt spacetimes (without and with gyratonic terms), which serve as backgrounds for the ensuing analysis on memory. The BD parameter $$\omega $$ ω and the scalar field ( $$\phi $$ ϕ ) profile, expectedly, distinguishes between different solutions. Choosing specific localised forms for the free metric functions $$H'(u)$$ H ′ ( u ) (related to the wave profile) and J(u) (the gyraton) we obtain displacement memory effects using both geodesics and geodesic deviation. An interesting and easy-to-understand exactly solvable case arises when $$\omega =-2$$ ω = - 2 (with J(u) absent) which we discuss in detail. For other $$\omega $$ ω (in the presence of J or without), numerically obtained geodesics lead to results on displacement memory which appear to match qualitatively with those found from a deviation analysis. Thus, the issue of how memory effects in BD theory may arise and also differ from their GR counterparts, is now partially addressed, at least theoretically, within the context of this new class of Kundt geometries.https://doi.org/10.1140/epjc/s10052-021-09118-4 |
| spellingShingle | Siddhant Siddhant Indranil Chakraborty Sayan Kar Kundt geometries and memory effects in the Brans–Dicke theory of gravity European Physical Journal C: Particles and Fields |
| title | Kundt geometries and memory effects in the Brans–Dicke theory of gravity |
| title_full | Kundt geometries and memory effects in the Brans–Dicke theory of gravity |
| title_fullStr | Kundt geometries and memory effects in the Brans–Dicke theory of gravity |
| title_full_unstemmed | Kundt geometries and memory effects in the Brans–Dicke theory of gravity |
| title_short | Kundt geometries and memory effects in the Brans–Dicke theory of gravity |
| title_sort | kundt geometries and memory effects in the brans dicke theory of gravity |
| url | https://doi.org/10.1140/epjc/s10052-021-09118-4 |
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