Outputs (38)

Ringdowns for black holes with scalar hair: The large mass case (2024)
Journal Article
D’Addario, G., Padilla, A., Saffin, P. M., Sotiriou, T. P., & Spiers, A. (2024). Ringdowns for black holes with scalar hair: The large mass case. Physical Review D, 109(8), Article 084046. https://doi.org/10.1103/physrevd.109.084046

Deviations from general relativity can alter the quasinormal mode (QNM) ringdown of perturbed black holes. It is known that a shift-symmetric (hence massless) scalar can only introduce black hole hair if it couples to the Gauss-Bonnet invariant, in w... Read More about Ringdowns for black holes with scalar hair: The large mass case.

The cosmological constant is probably still zero (2023)
Journal Article
Liu, Y., Padilla, A., & Pedro, F. G. (2023). The cosmological constant is probably still zero. Journal of High Energy Physics, 2023(10), Article 14. https://doi.org/10.1007/JHEP10%282023%29014

We consider a wide class of four-dimensional effective field theories in which gravity is coupled to multiple four-forms and their dual scalar fields, with membrane sources charged under the corresponding three-form potentials. Four-form flux, quanti... Read More about The cosmological constant is probably still zero.

CMB constraints on monodromy inflation at strong coupling (2022)
Journal Article
Copeland, E. J., Cunillera, F., Moss, A., & Padilla, A. (2022). CMB constraints on monodromy inflation at strong coupling. Journal of Cosmology and Astroparticle Physics, 2022(09), Article 080. https://doi.org/10.1088/1475-7516/2022/09/080

We carry out a thorough numerical examination of field theory monodromy inflation at strong coupling. We perform an MCMC analysis using a Gaussian likelihood, fitting multiparameter models using CMB constraints on the spectral index and the tensor to... Read More about CMB constraints on monodromy inflation at strong coupling.

Generalised scalar-tensor theories and self-tuning (2022)
Journal Article
Copeland, E. J., Ghataore, S., Niedermann, F., & Padilla, A. (2022). Generalised scalar-tensor theories and self-tuning. Journal of Cosmology and Astroparticle Physics, 2022(3), Article 004. https://doi.org/10.1088/1475-7516/2022/03/004

We explore a family of generalised scalar-tensor theories that exhibit self-tuning to low scale anti de Sitter vacua, even in the presence of a large cosmological constant. We are able to examine the linearised fluctuations about these vacua and comp... Read More about Generalised scalar-tensor theories and self-tuning.

Quintessence and the Swampland: The Numerically Controlled Regime of Moduli Space (2022)
Journal Article
Cicoli, M., Cunillera, F., Padilla, A., & Pedro, F. G. (2022). Quintessence and the Swampland: The Numerically Controlled Regime of Moduli Space. Fortschritte der Physik / Progress of Physics, 70(4), Article 2200008. https://doi.org/10.1002/prop.202200008

We provide a detailed discussion of the main theoretical and phenomenological challenges of quintessence model building in any numerically controlled regime of the moduli space of string theory. We argue that a working quintessence model requires a l... Read More about Quintessence and the Swampland: The Numerically Controlled Regime of Moduli Space.

Quadratic curvature corrections to stringy effective actions and the absence of de Sitter vacua (2022)
Journal Article
Cunillera, F., Emond, W. T., Lehébel, A., & Padilla, A. (2022). Quadratic curvature corrections to stringy effective actions and the absence of de Sitter vacua. Journal of High Energy Physics, 2022(2), Article 12. https://doi.org/10.1007/jhep02%282022%29012

We investigate the combined effect of fluxes and higher-order curvature corrections, in the form of the Gauss-Bonnet term, on the existence of de Sitter vacua in a heterotic string inspired framework, compactified on spheres and tori. We first gain s... Read More about Quadratic curvature corrections to stringy effective actions and the absence of de Sitter vacua.

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.