# Gravity and Scalar Fields

@article{Sotiriou2015GravityAS, title={Gravity and Scalar Fields}, author={Thomas P. Sotiriou}, journal={Lecture Notes in Physics}, year={2015}, volume={892}, pages={3-24} }

Gravity theories with non-minimally coupled scalar fields are used as characteristic examples in order to demonstrate the challenges, pitfalls and future perspectives of considering alternatives to general relativity. These lecture notes can be seen as an illustration of features, concepts and subtleties that are present in most types of alternative theories, but they also provide a brief review of generalised scalar-tensor theories.

## 66 Citations

Equivalence principle in scalar-tensor gravity

- Geology
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We present a direct confirmation of the validity of the equivalence principle for unstructured test bodies in scalar tensor gravity. Our analysis is complementary to previous approaches and valid for…

Equations of motion in scalar-tensor theories of gravity: A covariant multipolar approach

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We discuss the dynamics of extended test bodies for a large class of scalar-tensor theories of gravitation. A covariant multipolar Mathisson-Papapetrou-Dixon type of approach is used to derive the…

1 2 O ct 2 01 5 Equivalence principle in scalar-tensor gravity

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We present a direct confirmation of the validity of the equivalence principle for unstructured test bodies in scalar tensor gravity. Our analysis is complementary to previous approaches and valid for…

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No-hair theorems in theories of gravity with a scalar field are briefly and critically reviewed. Their significance and limitations are discussed and potential evasions are considered.

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Application of nonlinear symmetry realization technique to gravity is studied. We identify the simplest extensions of the Poincare group suitable for nonlinear realization at the level of physical…

Einstein-Klein-Gordon system by gravitational decoupling

- PhysicsEPL (Europhysics Letters)
- 2018

We investigate how a spherically symmetric scalar field can modify the Schwarzschild vacuum solution when there is no exchange of energy-momentum between the scalar field and the central source of…

Tensor-multi-scalar theories: relativistic stars and 3 + 1 decomposition

- Physics, Mathematics
- 2015

Gravitational theories with multiple scalar fields coupled to the metric and each other—a natural extension of the well studied single-scalar-tensor theories—are interesting phenomenological…

Multipolar test body equations of motion in generalized gravity theories

- Physics
- 2015

We give an overview of the derivation of multipolar equations of motion of extended test bodies for a wide set of gravitational theories beyond the standard general relativistic framework. The…

Braneworld‐Klein‐Gordon System in the Framework of Gravitational Decoupling

- PhysicsFortschritte der Physik
- 2021

We analyze the effective field equations of the Randall‐Sundrum braneworld coupled with a Klein‐Gordon scalar field through the minimal geometric deformation decoupling method (MGD‐decoupling). We…

Selected topics in scalar–tensor theories and beyond

- PhysicsInternational Journal of Modern Physics D
- 2019

Scalar fields have played an important role in the development of the fundamental theories of physics as well as in other branches of physics such as gravitation and cosmology. For a long time, these…

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