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We analyze the heavy quark bound state spectrum using an order-dependent conformal mapping to re-sum the perturbative expansion for current correlators. The procedure consists of two main steps. Firstly, the Borel plane structure of the…

High Energy Physics - Phenomenology · Physics 2009-10-31 H. F. Jones , A. Ritz , I. L. Solovtsov

Functional methods can be applied to the quantum effective action to efficiently determine counterterms and matching conditions for effective field theories. We extend the toolbox to two-loop order and beyond and show how to evaluate the…

High Energy Physics - Phenomenology · Physics 2025-08-20 Javier Fuentes-Martín , Adrián Moreno-Sánchez , Ajdin Palavrić , Anders Eller Thomsen

We present a new algorithm to construct a purely four dimensional representation of higher-order perturbative corrections to physical cross-sections at next-to-leading order (NLO). The algorithm is based on the loop-tree duality (LTD), and…

High Energy Physics - Phenomenology · Physics 2016-09-12 German F. R. Sborlini , Felix Driencourt-Mangin , Roger Hernandez-Pinto , German Rodrigo

We study the bispectrum of large-scale structure in the EFTofLSS including corrections up to two-loop. We derive an analytic result for the double-hard limit of the two-loop correction, and show that the UV-sensitivity can be absorbed by…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-15 Tobias Baldauf , Mathias Garny , Petter Taule , Theo Steele

We study the bispectrum in Lagrangian perturbation theory. Extending past results for the power spectrum, we describe a method to efficiently compute the bispectrum in LPT, focusing on the Zeldovich approximation, in which contributions due…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-07 Shi-Fan Chen , Zvonimir Vlah , Martin White

We develop an approach to parametrize cosmological perturbations beyond linear order for general dark energy and modified gravity models characterized by a single scalar degree of freedom. We derive the full nonlinear action, focusing on…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-07 Giulia Cusin , Matthew Lewandowski , Filippo Vernizzi

We present a systematic method for determining the two-loop effective Lagrangian resulting from integrating out a set of heavy particles in an ultraviolet scalar theory. We prove that the matching coefficients are entirely determined from…

High Energy Physics - Phenomenology · Physics 2024-03-19 Javier Fuentes-Martín , Ajdin Palavrić , Anders Eller Thomsen

We introduce a new framework for perturbatively computing equilibrium thermodynamic properties of cosmological phase transitions to high loop orders, using the full four-dimensional resummed thermal effective potential and avoiding the…

High Energy Physics - Phenomenology · Physics 2025-07-10 Pablo Navarrete , Risto Paatelainen , Kaapo Seppänen , Tuomas V. I. Tenkanen

We revisit the determination of the two-loop spectral function in the shear channel of hot Yang-Mills theory. Correcting a technical error in an earlier computation and extending the result with a leading order Hard Thermal Loop resummation…

High Energy Physics - Phenomenology · Physics 2015-02-11 Aleksi Vuorinen , Yan Zhu

We reformulate the calculation of the dark matter-nucleon scattering cross sections based on the method of effective field theories. We assume that the scatterings are induced by the exchange of colored mediators, and construct the…

High Energy Physics - Phenomenology · Physics 2015-06-11 Junji Hisano , Ryo Nagai , Natsumi Nagata

We present a new analytic approach to describe large scale structure formation in the mildly non-linear regime. The central object of the method is the time-dependent probability distribution function generating correlators of the…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-09 Diego Blas , Mathias Garny , Mikhail M. Ivanov , Sergey Sibiryakov

Because large-scale structure surveys may very well be the next leading sources of cosmological information, it is important to have a precise understanding of the cosmological observables; for this reason, the Effective Field Theory of…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-13 Matthew Lewandowski , Leonardo Senatore

The perturbative approach to structure formation has recently received a lot of attention in the literature. In such setups the final predictions for observables like the power spectrum is often derived under additional approximations such…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-14 Matteo Fasiello , Zvonimir Vlah

The infrared exponentiation properties of dimensionally-regularized multi-loop scattering amplitudes are typically hidden at the level of the integrand, materializing only after integral evaluation. We address this long-standing problem by…

High Energy Physics - Theory · Physics 2019-07-22 Robert M. Schabinger

We present an efficient and accurate pipeline for the analysis of the redshift-space galaxy bispectrum multipoles at one-loop order in effective field theory (EFT). We provide a systematic theory derivation based on power counting, which…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-05 Thomas Bakx , Mikhail M. Ivanov , Oliver H. E. Philcox , Zvonimir Vlah

We present a new method for evaluating tensor integrals in the large-scale structure. Decomposing a $\Lambda$CDM-like universe into a finite sum of scaling universes using the FFTLog, we can recast loop integrals for biased tracers in the…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-21 Hayden Lee

A framework to represent and compute two-loop $N$-point Feynman diagrams as double-integrals is discussed. The integrands are 'generalised one-loop type" multi-point functions multiplied by simple weighting factors. The final integrations…

High Energy Physics - Phenomenology · Physics 2020-04-15 J. Ph. Guillet , E. Pilon , Y. Shimizu , M. S. Zidi

We investigate whether non-linear effects on the large-scale power spectrum of dark matter, namely the increase in small-scale power and the smearing of baryon acoustic oscillations, can be decreased by a log-transformation or emulated by…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-12 Maksim Greiner , Torsten A. Enßlin

We compute squared matrix elements at next-to-next-to-leading order in perturbative quantum chromodynamics for the production of two or three (on- or off-shell) photons mediated via (light or heavy) quark loops. Our method handles all cases…

High Energy Physics - Phenomenology · Physics 2025-10-22 Dario Kermanschah , Matilde Vicini

Higher-order radiative corrections play an important role in precision studies of the electroweak and Higgs sector, as well as for the detailed understanding of large backgrounds to new physics searches. For corrections beyond the one-loop…

High Energy Physics - Phenomenology · Physics 2016-08-16 Ayres Freitas