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We present a relativistic and model-independent method to derive structure-dependent electromagnetic finite-size effects. This is a systematic procedure, particularly well-suited for automatization, which works at arbitrarily high orders in…

High Energy Physics - Lattice · Physics 2021-11-19 M. Di Carlo , M. T. Hansen , N. Hermansson-Truedsson , A. Portelli

A generalized scheme for the construction of coherent states in the context of position-dependent effective mass systems has been presented. This formalism is based on the ladder operators and associated algebra of the system which are…

Quantum Physics · Physics 2017-01-04 Naila Amir , Shahid Iqbal

We analyse the phenomenological effects of a varying Dark Energy (DE) effective speed of sound parameter, $c^{2}_{\textrm{sd}}$, on the cosmological perturbations of three phantom DE models. Each of these models induce a particular abrupt…

General Relativity and Quantum Cosmology · Physics 2021-11-08 Imanol Albarran , Mariam Bouhmadi-López , João Marto

The knowledge of effective masses is a key ingredient to analyze numerous properties of semiconductors, like carrier mobilities, (magneto-)transport properties, or band extrema characteristics yielding carrier densities and density of…

We present a unified framework for the study of late time cosmic acceleration. Using methods of effective field theory, we show that existing proposals for late time acceleration can be subsumed in a single framework, rather than many…

High Energy Physics - Theory · Physics 2014-11-20 Minjoon Park , Scott Watson , Kathryn M. Zurek

Much of the theory for the lasso in the linear model $Y = X \beta^* + \varepsilon$ hinges on the quantity $2 \| X^\top \varepsilon \|_{\infty} / n$, which we call the lasso's effective noise. Among other things, the effective noise plays an…

Methodology · Statistics 2022-01-24 Johannes Lederer , Michael Vogt

We sketch an algorithm to generate exact anisotropic solutions starting from a barotropic EoS and setting an ansatz on the metric functions. To illustrate the method, we use a generalization of the polytropic equation of state consisting of…

General Relativity and Quantum Cosmology · Physics 2021-04-21 Héctor Hernández , Daniel Suárez-Urango , Luis A. Núñez

We study a set of universe models where the dark sector is described by a perfect fluid with an affine equation of state $P=P_0+\alpha \rho$, focusing specifically on cosmological perturbations in a flat universe. We perform a Monte Carlo…

Astrophysics · Physics 2008-11-26 Davide Pietrobon , Amedeo Balbi , Marco Bruni , Claudia Quercellini

General relativistic corrections to the expansion rate of the Universe arise when the Einstein equations are averaged over a spatial volume in a locally inhomogeneous cosmology. It has been suggested that they may contribute to the observed…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-01 Xinghai Zhao , Grant J. Mathews

For the Nonlinear Shr\"odinger Equation with disorder it was found numerically that in some regime of the parameters Anderson localization is destroyed and subdiffusion takes place for a long time interval. It was argued that the nonlinear…

Disordered Systems and Neural Networks · Physics 2014-09-16 Erez Michaely , Shmuel Fishman

We obtain the equation of state (EoS) for two-color QCD at low temperature and high density from the lattice Monte Carlo simulation. We find that the velocity of sound exceeds the relativistic limit ($c_s^2/c^2=1/3$) after BEC-BCS crossover…

High Energy Physics - Phenomenology · Physics 2022-10-14 Kei Iida , Etsuko Itou

We derive the low-energy effective action governing the infrared dynamics of relativistic superfluids at finite temperature. We organize our derivation in an effective field theory fashion-purely in terms of infrared degrees of freedom and…

High Energy Physics - Theory · Physics 2011-09-20 Alberto Nicolis

Conventional approaches to cosmology inference from galaxy redshift surveys are based on n-point functions, which are under rigorous perturbative control on sufficiently large scales. Here, we present an alternative approach, which employs…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-23 Fabian Schmidt , Franz Elsner , Jens Jasche , Nhat Minh Nguyen , Guilhem Lavaux

The characterization of dark energy is a central task of cosmology. To go beyond a cosmological constant, we need to introduce at least an equation of state and a sound speed and consider observational tests that involve perturbations. If…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-23 Domenico Sapone , Martin Kunz , Luca Amendola

We investigate Bayesian chiral effective field theory ($\chi$EFT) uncertainties, which assign a statistical interpretation to equation of state (EOS) distributions near nuclear saturation density, n$_0$, as well as constraints from…

Effective field theory provides a perturbative framework to study the evolution of cosmological large-scale structure. We investigate the underpinnings of this approach, and suggest new ways to compute correlation functions of cosmological…

High Energy Physics - Theory · Physics 2014-07-16 Sean M. Carroll , Stefan Leichenauer , Jason Pollack

We treat low-energy $^3$He-$\alpha$ elastic scattering in an Effective Field Theory (EFT) that exploits the separation of scales in this reaction. We compute the amplitude up to Next-to-Next-to-Leading Order (NNLO), developing a hierarchy…

Nuclear Theory · Physics 2022-07-06 Maheshwor Poudel , Daniel R. Phillips

Quantum cosmology is traditionally formulated in a minisuperspace setting, implicitly averaging fields over space to obtain homogeneous models. For universal reasons related to the uncertainty principle, quantum corrections then depend on…

General Relativity and Quantum Cosmology · Physics 2019-06-05 Martin Bojowald

We explore a class of effective field theory models of cosmic acceleration involving a metric and a single scalar field. These models can be obtained by starting with a set of ultralight pseudo-Nambu-Goldstone bosons whose couplings to…

General Relativity and Quantum Cosmology · Physics 2012-11-16 Jolyon K. Bloomfield , Eanna E. Flanagan

The linear matter power spectrum is an essential ingredient in all theoretical models for interpreting large-scale-structure observables. Although Boltzmann codes such as CLASS or CAMB are very efficient at computing the linear spectrum,…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-20 Giovanni Aricò , Raul E. Angulo , Matteo Zennaro