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We develop, discuss, and compare several inference techniques to constrain theory parameters in collider experiments. By harnessing the latent-space structure of particle physics processes, we extract extra information from the simulator.…

High Energy Physics - Phenomenology · Physics 2018-09-19 Johann Brehmer , Kyle Cranmer , Gilles Louppe , Juan Pavez

We carry out a comprehensive study of the dynamics of large-scale perturbations in quintessence scenarios. We model the contents of the Universe by a perfect fluid with equation of state w_f and a scalar field Q with potential V(Q). We are…

Astrophysics · Physics 2009-11-07 Michael Malquarti , Andrew R. Liddle

The nonminimal coupling (NMC) of the scalar field to the Ricci curvature is unavoidable in many cosmological scenarios. Inflation and quintessence models based on nonminimally coupled scalar fields are studied, with particular attention to…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Valerio Faraoni

Results on the rational approximation of functions containing singularities are presented. We build further on the ''lightning method'', recently proposed by Trefethen and collaborators, based on exponentially clustering poles close to the…

Numerical Analysis · Mathematics 2023-10-10 Astrid Herremans , Daan Huybrechs , Lloyd N. Trefethen

We present a method for constructing global analytical expressions that approximate a function over its entire range. These approximations not only mirror the original function as accurately as desired, but are purposefully created to…

High Energy Physics - Phenomenology · Physics 2024-07-09 Aviv Orly

It is shown that any realistic model of quintessence should be based on Supergravity (SUGRA) since the value of the quintessence field on the attractor is approximately the Planck mass. Under very general assumptions, the typical shape of a…

Astrophysics · Physics 2007-05-23 Philippe Brax , Jerome Martin

Fitting probabilistic models to data is often difficult, due to the general intractability of the partition function and its derivatives. Here we propose a new parameter estimation technique that does not require computing an intractable…

Machine Learning · Computer Science 2015-03-13 Jascha Sohl-Dickstein , Peter Battaglino , Michael R. DeWeese

In pump-probe spectroscopy, one often needs to analyse the transmission or reflection of electromagnetic waves through optically pumped media. Here, it is common practice to approximate the analysis in order to extract non-equilibrium…

Optics · Physics 2019-02-26 Peter Karlsen , Euan Hendry

We study the dynamics of a quintessence model based on two interacting scalar fields. The model can account for the (recent) accelerated expansion of the Universe suggested by astronomical observations. Acceleration can be permanent or…

Astrophysics · Physics 2010-05-28 M. C. Bento , O. Bertolami , N. C. Santos

In this paper, we formulate a new \emph{multiple-correction method}. The goal is to accelerate the rate of convergence. In particular, we construct some sequences to approximate the Euler-Mascheroni and Landau constants, which are faster…

Number Theory · Mathematics 2014-09-04 Xiaodong Cao , Hongmin Xu , Xu You

We derive the slow-roll conditions for a non-minimally coupled scalar field (extended quintessence) during the radiation/matter dominated era extending our previous results for thawing quintessence. We find that the ratio…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Takeshi Chiba , Masaru Siino , Masahide Yamaguchi

We study the Galileon scalar field model arising as a decoupling limit of the Dvali-Gababdaze-Porrati (DGP) construction for the late time acceleration of the universe. The model has one extra Galileon correction term over and above the…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-11 Md. Wali Hossain , Anjan A. Sen

Recent advances in steady-state analysis of power systems have introduced the equivalent split-circuit approach and corresponding continuation methods that can reliably find the correct physical solution of large-scale power system…

Systems and Control · Computer Science 2018-04-24 Martin R. Wagner , Amritanshu Pandey , Marko Jereminov , Larry Pileggi

Instance sparsification is well-known in the world of exact computation since it is very closely linked to the Exponential Time Hypothesis. In this paper, we extend the concept of sparsification in order to capture subexponential time…

Computational Complexity · Computer Science 2014-02-17 Edouard Bonnet , Vangelis Th. Paschos

We create a new, functional calculus, approach to approximation of C_0-semigroups on Banach spaces. As an application of this approach, we obtain optimal convergence rates in classical approximation formulas for C_0-semigroups. In fact, our…

Functional Analysis · Mathematics 2013-07-08 Alexander Gomilko , Yuri Tomilov

We investigate entanglement detection when the local measurements only nearly correspond to those intended. This corresponds to a scenario in which measurement devices are not perfectly controlled, but nevertheless operate with bounded…

Quantum Physics · Physics 2022-06-22 Simon Morelli , Hayata Yamasaki , Marcus Huber , Armin Tavakoli

In this note we analyse \emph{quantitative} approximation properties of a certain class of \emph{nonlocal} equations: Viewing the fractional heat equation as a model problem, which involves both \emph{local} and \emph{nonlocal}…

Analysis of PDEs · Mathematics 2017-08-22 Angkana Rüland , Mikko Salo

The effective potential is a widely used phenomenological tool to investigate phase transitions occurring in the early Universe at finite temperature. In the standard perturbative treatment the potential becomes complex in some region of…

High Energy Physics - Phenomenology · Physics 2023-11-10 Károly Seller

The method of self-similar factor approximants is completed by defining the approximants of odd orders, constructed from the power series with the largest term of an odd power. It is shown that the method provides good approximations for…

Mathematical Physics · Physics 2009-11-13 V. I. Yukalov , E. P. Yukalova

The late time acceleration of the Universe can be characterized in terms of an extra, time dependent, component of the universe -- dark energy. The simplest proposal for dark energy is a scalar-tensor theory -- quintessence -- which…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-06 Carlos García-García , Emilio Bellini , Pedro G. Ferreira , Dina Traykova , Miguel Zumalacárregui