| Project/Area Number |
19F19313
|
|---|
| Research Category |
Grant-in-Aid for JSPS Fellows
|
| Allocation Type | Single-year Grants |
|---|
| Section | 外国 |
|---|
| Review Section |
Basic Section 15010:Theoretical studies related to particle-, nuclear-, cosmic ray and astro-physics
|
|---|
| Research Institution | Kyoto University |
|---|
Principal Investigator |
向山 信治 京都大学, 基礎物理学研究所, 教授 (40396809)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
GORJI MOHAMMAD ALI 京都大学, 基礎物理学研究所, 外国人特別研究員
|
|---|
| Project Period (FY) |
2019-11-08 – 2022-03-31
|
| Project Status |
Completed (Fiscal Year 2021)
|
| Budget Amount *help |
¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 2021: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 2020: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 2019: ¥400,000 (Direct Cost: ¥400,000)
|
|---|
| Keywords | gravitation / cosmology / gravitatioal waves |
|---|
| Outline of Research at the Start |
We seek class of modified theories of gravity which not only address dark matter/dark energy problems but also being consistent with the observations of the gravitational waves and binary pulsars. We also explore the effects of Abelian and non-Abelian gauge fields in the context of cosmology. In particular, we consider their effects on the power spectrum of the primordial gravitational waves. We also consider their effects during inflationary era to see whether they can generate primordial magnetic field.
|
| Outline of Annual Research Achievements |
Probing dark sector via GWs: We have obtained an analytical expression for the stochastic gravitational wave (GW) spectrum which includes the effects of axions and dark photons. We published the result in Journal of High Energy Physics (JHEP).
Dark photon dark matter: We have shown that dark photons can be produced during inflation and play the role of dark matter later. We published the result in JHEP.
Disformal transformation and Petrov classification: We have shown that while a Petrov type of a solution in scalar-tensor and vector-tensor theories remain unchanged under a conformal transformation, it can change under a disformal transformation. We published the result in Journal of Cosmology and Astroparticle Physics (JCAP).
|
| Research Progress Status |
令和3年度が最終年度であるため、記入しない。
|
| Strategy for Future Research Activity |
令和3年度が最終年度であるため、記入しない。
|
