k-Essence, superluminal propagation, causality and emergent geometry

By E. Babichev, V. Mukhanov, A. Vikman. 2007

431 citations recorded by the source corpus.

The k-essence theories admit in general the superluminal propagation of the perturbations on classical backgrounds. We show that in spite of the superluminal propagation the causal paradoxes do not arise in these theories and in this respect they are not less safe than General Relativity.

Subfields: Astronomy and Astrophysics, Atomic and Molecular Physics, and Optics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/bd8953062b43da1757c776ba56724bcdbac3566c

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

In Atomic and Molecular Physics, and Optics

In Nuclear and High Energy Physics

Citations in the corpus

Solid holography and massive gravity (2015, background): “However, as has been argued previously in [46], having a superluminal propagation of perturbations on an emergent effective geometry due to a condensate of scalar fields does not lead to any causal paradoxes as long as certain conditions are met.”
Massive Gravity (2014, background): “This result should sound familiar as it echoes what has already been shown to happen in the decoupling limit of massive gravity, or here of the Proca field theory (see [43, 468] for related discussions in that case).”
Cosmology with Mimetic Matter (2014, background): “ found another interesting novel extension which allows for 1Note that this superluminality does not imply any causal paradoxes or other inconsistencies on the level of eﬀective ﬁeld theory, see e.g. [10]. 16 the nontrivial speed of sound. This can be achieved by adding higher-orderderivative terms ”
Dust of dark energy (2010, result): “[46] E.”
Cosmology and Fundamental Physics with the Euclid Satellite (2012, background): “However it was shown in [97] that this does not lead to any causal paradoxes.”
G-bounce (2011, background): “At best, the trajectories cross the line of vanishing sound speed, corresponding to a singularity in the acoustic metric, which can appear in non-canonical theories [37].”
Theoretical Aspects of Massive Gravity (2011, background): “It has been argued that such superluminality is a sign that the theory cannot be UV completed by a standard local Lorentz invariant theory [160], though others have argued that this is not a problem [161].”
The effective theory of quintessence: the w < 1 side unveiled (2008, background): “for positive c 2 s, M 4 < 0 implies that scalar perturbations propagate super-luminally [14, 15].”
Imperfect Dark Energy from Kinetic Gravity Braiding (2010, background): “[50] (see also the most recent paper [57] and older works [58, 59, 60, 61]) and claim that this superluminality does not imply any inconsistencies.”
Beyond the Cosmological Standard Model (2014, neutral): “See [149] for earlier arguments in the context of P (X) theories.”