Outputs (42)

A stringy perspective on the coincidence problem (2021)
Journal Article
Cunillera, F., & Padilla, A. (2021). A stringy perspective on the coincidence problem. Journal of High Energy Physics, 2021(10), Article 55. https://doi.org/10.1007/JHEP10%282021%29055

We argue that, for string compactifications broadly consistent with swampland constraints, dark energy is likely to signal the beginning of the end of our universe as we know it, perhaps even through decompactification, with possible implications for... Read More about A stringy perspective on the coincidence problem.

Deconstructing higher order clockwork gravity (2021)
Journal Article
Avgoustidis, A., Niedermann, F., Padilla, A., & Saffin, P. M. (2021). Deconstructing higher order clockwork gravity. Physical Review D, 103(12), Article 124007. https://doi.org/10.1103/physrevd.103.124007

We consider the higher order clockwork theory of gravitational interactions, whereby a number of gravitons are coupled together with TeV strength, but nevertheless generate a Planck scale coupling to matter without the need for a dilaton. It is shown... Read More about Deconstructing higher order clockwork gravity.

Massive Galileons and Vainshtein screening (2021)
Journal Article
Burrage, C., Coltman, B., Padilla, A., Saadeh, D., & Wilson, T. (2021). Massive Galileons and Vainshtein screening. Journal of Cosmology and Astroparticle Physics, 2021(02), Article 050. https://doi.org/10.1088/1475-7516/2021/02/050

The Vainshtein screening mechanism relies on nonlinear interaction terms becoming dominant close to a compact source. However, theories displaying this mechanism are generally understood to be low-energy theories: it is unclear that operators emergin... Read More about Massive Galileons and Vainshtein screening.

Unimodular vs nilpotent superfield approach to pure dS supergravity (2021)
Journal Article
Bansal, S., Nagy, S., Padilla, A., & Zavala, I. (2021). Unimodular vs nilpotent superfield approach to pure dS supergravity. Journal of High Energy Physics, 2021(1), Article 146 (2021). https://doi.org/10.1007/jhep01%282021%29146

Recent progress in understanding de Sitter spacetime in supergravity and string theory has led to the development of a four dimensional supergravity with spontaneously broken supersymmetry allowing for de Sitter vacua, also called de Sitter supergrav... Read More about Unimodular vs nilpotent superfield approach to pure dS supergravity.

Dark energy loopholes some time after GW170817 (2020)
Journal Article
Bordin, L., Copeland, E. J., & Padilla, A. (2020). Dark energy loopholes some time after GW170817. Journal of Cosmology and Astroparticle Physics, 2020(11), Article 063. https://doi.org/10.1088/1475-7516/2020/11/063

We revisit the constraints on scalar tensor theories of modified gravity following the purge of GW170817. We pay particular attention to dynamical loopholes where the anomalous speed of propagation of the gravitational wave can vanish on-shell, when... Read More about Dark energy loopholes some time after GW170817.

Cosmological consequences of Omnia Sequestra (2019)
Journal Article
Coltman, B., Li, Y., & Padilla, A. (2019). Cosmological consequences of Omnia Sequestra. Journal of Cosmology and Astroparticle Physics, 2019(06), Article 017. https://doi.org/10.1088/1475-7516/2019/06/017

Vacuum energy sequestering is a mechanism for cancelling off the radiative corrections to vacuum energy. The most comprehensive low energy model, proposed in [1], has the ability to cancel off radiative corrections to vacuum energy for loops of both... Read More about Cosmological consequences of Omnia Sequestra.

Dark Energy after GW170817 Revisited (2019)
Journal Article
Copeland, E. J., Kopp, M., Padilla, A., Saffin, P. M., & Skordis, C. (2019). Dark Energy after GW170817 Revisited. Physical Review Letters, 122(6), Article 061301. https://doi.org/10.1103/physrevlett.122.061301

We revisit the status of scalar-tensor theories with applications to dark energy in the aftermath of the gravitational wave signal GW170817 and its optical counterpart GRB170817A. At the level of the cosmological background, we identify a class of th... Read More about Dark Energy after GW170817 Revisited.

Higher order clockwork gravity (2018)
Journal Article
Niedermann, F., Padilla, A., & Saffin, P. M. (2018). Higher order clockwork gravity. Physical Review D, 98(10), Article 104014. https://doi.org/10.1103/physrevd.98.104014

We present a higher order generalisation of the clockwork mechanism starting from an underlying non-linear multigravity theory with a single scale and nearest neighbour ghost-free interactions. Without introducing any hierarchies in the underlying po... Read More about Higher order clockwork gravity.

Non-perturbative aspects of galileon duality (2018)
Journal Article
Millington, P., Niedermann, F., & Padilla, A. (in press). Non-perturbative aspects of galileon duality. European Physical Journal C: Particles and Fields, 78(7), https://doi.org/10.1140/epjc/s10052-018-6029-0

We study quantum aspects of the galileon duality, especially in the case of a particular interacting galileon theory that is said to be dual to a free theory through the action of a simultaneous field and coordinate transformation. This would appear... Read More about Non-perturbative aspects of galileon duality.

Vainshtein in the UV and a Wilsonian analysis of derivatively coupled scalars (2018)
Journal Article
Padilla Antonio, A., & Saltas, I. (2018). Vainshtein in the UV and a Wilsonian analysis of derivatively coupled scalars. Journal of Cosmology and Astroparticle Physics, 2018(6), https://doi.org/10.1088/1475-7516/2018/06/039

In the first part of this paper we critically examine the ultra-violet implications of theories that exhibit Vainshtein screening, taking into account both the standard Wilsonian perspective as well as more exotic possibilities. Aspects of this discu... Read More about Vainshtein in the UV and a Wilsonian analysis of derivatively coupled scalars.