Unified f(R) gravity at local scales

Abstract

We explore the shifted $$f(R) (\propto R^{1+\delta })$$ f ( R ) ( ∝ R 1 + δ ) model with $${\delta }$$ δ as a distinguishing physical parameter for the study of constraints at local scales. The corresponding dynamics confronted with different geodesics (null and non-null) along with their conformal analog are investigated. For null geodesics, we discuss the light deflection angle, whereas, for non-null geodesics under the weak field limit, we investigate the perihelion advance of the Mercury orbit in f(R) Schwarzschild background, respectively. The extent of an additional force, appearing for non-null geodesics, depends on $$\delta $$ δ . Such phenomenological investigations allow us to strictly constrain $$\delta $$ δ to be approximately $${\mathcal {O}}(10^{-6})$$ O ( 10 - 6 ) with a difference of unity in orders at galactic and planetary scales and seem to provide a unique f(R) at local scales. Our results suggest that the present form of the model is suitable for the alternative explanation of dark matter-like effects at local scales.

Sustainable stretchable batteries for next-generation wearables

“…190 However, recent reports have put into question the true sustainability of DESs in terms of their production methods and their environmental and human impact. [191][192][193] Thus it presents an opportunity to develop new sustainable electrolyte systems for stretchable batteries. In general, the leakage of the battery electrolyte should be avoided at all costs due to the use of toxic electrolytes, or in the cases where it is biocompatible, to prevent the degradation of battery operation.…”

Revisiting compact star in $F(R)$ gravity: Roles of chameleon potential and energy conditions

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Initial conditions for the scalaron dark matter

“…It was suggested that dark matter in our universe can be explained in frames of models of f (R) gravity [1][2][3][4][5][6][7][8][9] (see also reviews [10,11]). In these models, a new weakly interacting degree of freedom (the scalaron) arises in the gravitational sector, which can be associated with dark matter.…”