MG14 - Talk detail |
Participant |
Loureiro Giacchini, Breno | |||||||
Institution |
Centro Brasileiro de Pesquisas Físicas - Rua Dr. Xavier Sigaud, 150 / 604C - Rio de Janeiro - Rio de Janeiro - Brazil | |||||||
Session |
AT1 |
Accepted |
Yes |
Order |
10 |
Time |
18:10 | 15' |
Talk |
Oral abstract |
Title |
Light Deflection in Semiclassical Higher-Derivative Gravity | |||||
Coauthors | ||||||||
Abstract |
Higher-derivative gravity, i.e. the system defined by General Relativity's Lagrangian augmented by curvature-squared terms, is a renormalizable gravity model, along with its matter couplings. This model has two free parameters, $\alpha$ and $\beta$, which couple the higher-order terms $R^2$ and $R_{\mu\nu}^2$, respectively. In this work we study the bending of light in the framework of higher-derivative gravity utilizing both classical and semiclassical approaches. We show that the Ricci-squared sector is associated to a repulsive interaction and, at the tree-level, yields dispersive photon propagation yet in first order. Also, a comparison between the predicted results and experimental data allows us to set an upper bound on the coupling constant $\beta$. |
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Pdf file |
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Session |
AT2 |
Accepted |
Yes |
Order |
99 |
Time |
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Talk |
Poster abstract |
Title |
Experimental Limits On The Free Parameters Of Higher-Derivative Gravity | |||||
Coauthors | ||||||||
Abstract |
Higher-derivative gravity (HDG) has two free parameters, $\alpha$ and $\beta$, which couple the curvature-squared terms, $R^2$ and $R_{\mu\nu}^2$, respectively. Both Newtonian inverse-square law experiments and relativistic effects have recently been used to stablish bounds to many interesting models, such as $f(R)$ and scalar-tensor theories, extra-dimension scenarios and Standard Model extensions. Our aim in this work is to review those experimental results in the context of HDG. The strictest limit we report ($\alpha,\beta\leq10^{58}$) follows from E\"ot-Wash torsion-balance experiments. Interestingly, the bound on $\beta$ due to semiclassical deflection of photons grazing the Sun is only three orders of magnitude larger. |
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Pdf file |
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