Causality in 3D massive gravity theories

Edelstein, Jose D.
Giribet, Gaston
Gomez, Carolina
Kilicarslan, Ercan
Leoni, Matias
Tekin, Bayram
We study the constraints coming from the local causality requirement in various 2 + 1 dimensional dynamical theories of gravity. In topologically massive gravity, with a single parity noninvariant massive degree of freedom, and in new massive gravity, with two massive spin-2 degrees of freedom, causality and unitarity are compatible with each other and both require the Newton's constant to be negative. In their extensions, such as the Born-Infeld gravity and the minimal massive gravity the situation is similar and quite different from their higher dimensional counterparts, such as quadratic (e.g., Einstein-Gauss-Bonnet) or cubic theories, where causality and unitarity are in conflict. We study the problem both in asymptotically flat and asymptotically anti-de Sitter spaces.


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Altaş Kiracı, Emel; Tekin, Bayram; Department of Physics (2018)
In a nonlinear theory, such as gravity, physically relevant solutions are usually hard to find. Therefore, starting from a background exact solution with symmetries, one uses the perturbation theory, which albeit approximately, provides a lot of information regarding a physical solution. But even this approximate information comes with a price: the basic premise of a perturbative solution is that it should be improvable. Namely, by going to higher order perturbation theory, one should be able to improve and ...
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We study the local causality issue via the Shapiro time-delay computations in the on-shell consistent exotic massive gravity in three dimensions. The theory shows time delay as opposed to time advance despite having a ghost at the linearized level both for asymptotically flat and anti-de Sitter spacetimes. We also prove a Birkhoff-like theorem: any solution with a hypersurface orthogonal non-null Killing vector field is conformally flat; and we find some exact solutions.
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Sisman, Tahsin Cagri; Gullu, Ibrahim; Tekin, Bayram (2012-08-24)
We explicitly confirm the expectation that generic Lovelock gravity in D dimensions has a unitary massless spin-2 excitation around any one of its constant curvature vacua just like the cosmological Einstein gravity. The propagator of the theory reduces to that of Einstein's gravity, but scattering amplitudes must be computed with an effective Newton's constant which we provide. Tree-level unitarity imposes a single constraint on the parameters of the theory yielding a wide range of unitary region. As an ex...
Causality in curved space
Aljasem Alashour, Bassem; Tekin, Bayram; Department of Physics (2018)
The notion of Causality is a key concept in formulating theories that describe real physical systems. So when a proposed model violates this concept this usually signals the existence of an error in the conceptual formulation or in the physical understanding of the results, which might indicate to us which models should we pursue, modify or drop all together. In this work the possibility of causality violations introduced by modifying Einstein gravity is studied using the idea of the time-delay introduced t...
Entangled Harmonic Oscillators and Space-Time Entanglement
Başkal, Sibel; Kim, Young S.; Noz, Marilyn E. (MDPI AG, 2016-6-28)
The mathematical basis for the Gaussian entanglement is discussed in detail, as well as its implications in the internal space-time structure of relativistic extended particles. It is shown that the Gaussian entanglement shares the same set of mathematical formulas with the harmonic oscillator in the Lorentz-covariant world. It is thus possible to transfer the concept of entanglement to the Lorentz-covariant picture of the bound state, which requires both space and time separations between two constituent p...
Citation Formats
J. D. Edelstein, G. Giribet, C. Gomez, E. Kilicarslan, M. Leoni, and B. Tekin, “Causality in 3D massive gravity theories,” PHYSICAL REVIEW D, pp. 0–0, 2017, Accessed: 00, 2020. [Online]. Available: