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Communications in mathematical physics 399(2), 1039 - 1101 (2023). doi:10.1007/s00220-022-04571-y, We study the Borel summation of the Gromov-Witten potential for the resolved conifold. The Stokes phenomena associated to this Borel summation are shown to encode the Donaldson-Thomas invariants of the resolved conifold, having a direct relation to the Riemann-Hilbert problem formulated by T. Bridgeland. There exist distinguished integration contours for which the Borel summation reproduces previous proposals for the non-perturbative topological string partition functions of the resolved conifold. These partition functions are shown to have another asymptotic expansion at strong topological string coupling. We demonstrate that the Stokes phenomena of the strong-coupling expansion encode the DT invariants of the resolved conifold in a second way. Mathematically, one finds a relation to Riemann-Hilbert problems associated to DT invariants which is different from the one found at weak coupling. The Stokes phenomena of the strong-coupling expansion turn out to be closely related to the wall-crossing phenomena in the spectrum of BPS states on the resolved conifold studied in the context of supergravity by D. Jafferis and G. Moore., Published by Springer, Heidelberg

We study energy correlations in states created by a heavy operator acting on the vacuum in a conformal field theory. We argue that the energy correlations in such states exhibit two characteristic regimes as functions of the angular separations between the calorimeters: power-like growth at small angles described by the light-ray OPE and slowly varying, or ``flat'', function at larger angles. The transition between the two regimes is controlled by the scaling dimension of the heavy operator and the dynamics of the theory. We analyze this phenomenon in detail in the planar ${\cal N}=4$ SYM theory both at weak and strong coupling. An analogous transition was previously observed in QCD in the measurement of the angular energy distribution of particles belonging to the same energetic jet. In that case it corresponds to the transition from the light-ray OPE, perturbative regime described in terms of correlations between quarks and gluons to the flat, non-perturbative regime described in terms of correlations between hadrons., Comment: 59 pages, 6 figures

We initiate the study of transverse momentum-dependent (TMD) fragmentation functions for heavy quarks, demonstrate their factorization in terms of novel nonperturbative matrix elements in heavy-quark effective theory (HQET), and prove new TMD sum rules that arise from heavy-quark spin symmetry. We discuss the phenomenology of heavy-quark TMD FFs at $B$ factories and find that the Collins effect, in contrast to claims in the literature, is not parametrically suppressed by the heavy-quark mass. We further calculate all TMD parton distribution functions for the production of heavy quarks from polarized gluons within the nucleon and use our results to demonstrate the potential of the future EIC to resolve TMD heavy-quark fragmentation in semi-inclusive DIS, complementing the planned EIC program to use heavy quarks as probes of gluon distributions., 42 pages + references, 7 figures

Parametrizing TMD parton densities and fragmentation functions in ways that consistently match their large transverse momentum behavior in standard collinear factorization has remained notoriously difficult. We show how the problem is solved in a recently introduced set of steps for combining perturbative and nonperturbative transverse momentum in TMD factorization. Called a ``bottom-up'' approach in a previous article, here we call it a ``hadron structure oriented'' (HSO) approach to emphasize its focus on preserving a connection to the TMD parton model interpretation. We show that the associated consistency constraints improve considerably the agreement between parametrizations of TMD functions and their large-$k_T$ behavior, as calculated in collinear factorization. The procedure discussed herein will be important for guiding future extractions of TMD parton densities and fragmentation functions and for testing TMD factorization and universality. We illustrate the procedure with an application to semi-inclusive deep inelastic scattering (SIDIS) structure functions at an input scale $Q_0$, and we show that there is improved consistency between different methods of calculating at moderate transverse momentum. We end with a discussion of plans for future phenomenological applications., Comment: 27 pages, 8 figures

We present a non-perturbative method for calculating the abundance of primordial black holes given an arbitrary one-point probability distribution function for the primordial curvature perturbation, $P(\zeta)$. A non-perturbative method is essential when considering non-Gaussianities that cannot be treated using a conventional perturbative expansion. To determine the full statistics of the density field, we relate $\zeta$ to a Gaussian field by equating the cumulative distribution functions. We consider two examples: a specific local-type non-Gaussian distribution arising from ultra slow roll models, and a general piecewise model for $P(\zeta)$ with an exponential tail. We demonstrate that the enhancement of primordial black hole formation is due to the intermediate regime, rather than the far tail. We also show that non-Gaussianity can have a significant impact on the shape of the primordial black hole mass distribution., Comment: 9 pages, 2 figures; Version 3: matches published version

The European physical journal / C 83, 536 (2023). doi:10.1140/epjc/s10052-023-11692-8, Double parton distributions are the nonperturbative ingredients needed forcomputing double parton scattering processes in hadron-hadron collisions. They describea variety of correlations between two partons in a hadron and depend on a large numberof variables, including two independent renormalization scales. This makes it challengingto compute their scale evolution with satisfactory numerical accuracy while keeping com-putational costs at a manageable level. We show that this problem can be solved usinginterpolation on Chebyshev grids, extending the methods we previously developed for or-dinary single-parton distributions. Using an implementation of these methods in the C++library ChiliPDF, we study for the first time the evolution of double parton distributions beyond leading order in perturbation theory., Published by Springer, Heidelberg

With increasing requirements for greater precision, it becomes essential to describe the effects of isospin breaking induced by both quark masses and electro-magnetic effects. In this work we have performed a lattice analysis of the weak decay constants of the pseudoscalar mesons including such isospin breaking effects, with particular consideration being given to the state mixing of the $\pi^0$, $\eta$ and $\eta^\prime$. We also detail extensions to the non-perturbative RI$^\prime$-MOM renormalization scheme for application to non-degenerate flavour-neutral operators which are permitted to mix, and present initial results. Using flavour-breaking expansions in terms of quark masses and charges we reach decay constant determinations at physical quark masses for all but the $\eta^\prime$, demonstrating in principle how precision determinations of all pseudoscalar decay constants could be reached in lattice QCD with QED and strong isospin-breaking., Comment: 11 pages, 6 figures, version for submission to PRD

Non-perturbatively computing the hadronic vacuum polarization at large photon virtualities and making contact with perturbation theory enables a precision determination of the electromagnetic coupling at the $Z$ pole, which enters global electroweak fits. In order to achieve this goal ab initio using lattice QCD, one faces the challenge that, at the short distances which dominate the observable, discretization errors are hard to control. Here we address challenges of this type with the help of static screening correlators in the high-temperature phase of QCD, yet without incurring any bias. The idea is motivated by the observations that (a) the cost of high-temperature simulations is typically much lower than their vacuum counterpart, and (b) at distances $x_3$ far below the inverse temperature $1/T$, the operator-product expansion guarantees the thermal correlator of two local currents to deviate from the vacuum correlator by a relative amount that is power-suppressed in $(x_3\:T)$. The method is first investigated in lattice perturbation theory, where we point out the appearance of an O$(a^2 \log(1/a))$ lattice artifact in the vacuum polarization with a prefactor that we calculate. It is then applied to non-perturbative lattice QCD data with two dynamical flavors of quarks. Our lattice spacings range down to 0.049 fm for the vacuum simulations and down to 0.033 fm for the simulations performed at a temperature of 250 MeV., 32 pages, 8 figures, 6 tables

Phase transitions in a non-perturbative regime can be studied by ab initio Lattice Field Theory methods. The status and future research directions for LFT investigations of Quantum Chromo-Dynamics under extreme conditions are reviewed, including properties of hadrons and of the hypothesized QCD axion as inferred from QCD topology in different phases. We discuss phase transitions in strong interactions in an extended parameter space, and the possibility of model building for Dark Matter and Electro-Weak Symmetry Breaking. Methodological challenges are addressed as well, including new developments in Artificial Intelligence geared towards the identification of different phases and transitions., Comment: 94 pages, 23 figures, GGI workshop "Phase Transitions in Particle Physics" review - v2: minor revisions and typo corrected, matches accepted version on PPNP

One of the greatest challenges in quantum chromodynamics is understanding the hadronization mechanism, which is also crucial for carrying out precision physics with jet substructure. In this Letter, we combine recent advancements in our understanding of the field theory-based nonperturbative structure of the soft drop jet mass with precise perturbative calculations of its multi-differential variants at next-to-next-to-leading logarithmic (NNLL) accuracy. This enables a systematic study of its hadronization power corrections in a completely model-independent way. We calibrate and test hadronization models and their interplay with parton showers by comparing our universality predictions with various event generators for quark and gluon initiated jets in both lepton-lepton and hadron-hadron collisions. We find that hadronization models perform better for quark jets relative to gluon jets. Our results provide the necessary toolkit for precision studies with the soft drop jet mass motivating future analyses using real world collider data. The nontrivial constraints derived in our framework are useful for improving the modeling of hadronization and its interface with parton showers in next generation event generators., 8 pages, 6 figures + supplemental material (4 pages, 5 figures)

Physical review / D 107(4), 043530 (2023). doi:10.1103/PhysRevD.107.043530, We investigate the out-of-equilibrium production of scalar dark matter (DM) from the inflaton condensate during inflation and reheating. We assume that this scalar couples only to the inflaton via a direct quartic coupling and is minimally coupled to gravity. We consider all possible production regimes: purely gravitational, weak direct coupling (perturbative), and strong direct coupling (nonperturbative). For each regime, we use different approaches to determine the dark matter phase space distribution and the corresponding relic abundance. For the purely gravitational regime, scalar dark matter quanta are copiously excited during inflation resulting in an infrared (IR) dominated distribution function and a relic abundance which overcloses the universe for a reheating temperature Treh>34 GeV. A nonvanishing direct coupling induces an effective DM mass and suppresses the large IR modes in favor of ultraviolet (UV) modes and a minimal scalar abundance is generated when the interference between the direct and gravitational couplings is maximal. For large direct couplings, backreaction on the inflaton condensate is accounted for by using the Hartree approximation and lattice simulation techniques. Since scalar DM candidates can behave as noncold dark matter, we estimate the impact of such species on the matter power spectrum and derive the corresponding constraints from the Lyman-α measurements. We find that they correspond to a lower bound on the DM mass of ≳3×10-4 eV for purely gravitational production, and ≳20 eV for direct coupling production. We discuss the implications of these results., Published by Inst., Woodbury, NY

The modern S-Matrix Bootstrap provides non-perturbative bounds on low-energy aspects of scattering amplitudes, leveraging the constraints of unitarity, analyticity and crossing. Typically, the solutions saturating such bounds also saturate the unitarity constraint as much as possible, meaning that they are almost exclusively elastic. This is expected to be unphysical in $d>2$ because of Aks' theorem. We explore this issue by adding inelasticity as an additional input, both using a primal approach in general dimensions which extends the usual ansatz, and establishing a dual formulation in the 2d case. We then measure the effects on the low-energy observables where we observe stronger bounds than in the standard setup., 8 pages, 14 figures; v2 minor modifications

The modern S-Matrix Bootstrap provides non-perturbative bounds on low-energy aspects of scattering amplitudes, leveraging the constraints of unitarity, analyticity and crossing. Typically, the solutions saturating such bounds also saturate the unitarity constraint as much as possible, meaning that they are almost exclusively elastic. This is expected to be unphysical in $d>2$ because of Aks' theorem. We explore this issue by adding inelasticity as an additional input, both using a primal approach in general dimensions which extends the usual ansatz, and establishing a dual formulation in the 2d case. We then measure the effects on the low-energy observables where we observe stronger bounds than in the standard setup.

In four-dimensional $\mathcal{N}=4$ super Yang-Mills theory with gauge group $SU(N)$, we present a closed-form solution for a family of integrated four-point functions involving stress tensor multiplet composites of arbitrary R-charge. These integrated correlators are shown to be equivalent to a one-dimensional semi-infinite lattice of harmonic oscillators with nearest-neighbor interactions, evolving over the fundamental domain of $SL(2,\mathbb{Z})$. The solution, exceptionally simple in an $SL(2,\mathbb{Z})$-invariant eigenbasis, is exact in the R-charge $p$, rank $N$, and complexified gauge coupling $\tau$. This permits a systematic and non-perturbative large charge expansion for any $N$ and $\tau$. Especially novel is a double-scaled "gravity regime" in which $p \sim N^2 \gg 1$, holographically dual to a large charge regime of semiclassical type IIB string theory in AdS$_5\, \times$ S$^5$. Our results in this limit provide a holographic computation of integrated semiclassical string amplitudes at arbitrary string coupling, including an emergent string scale with a large charge dressing factor. We compare to extremal correlators in superconformal QCD, for which we predict new genus expansions at large charge scaling with $N$., Comment: 31 pages + appendices

We compute the strong coupling constant of Landau gauge QCD in the full complex momentum plane, both directly and via spectral reconstruction. In particular, we consider the Taylor coupling given by the product of ghost and gluon dressing functions. Assuming spectral representations for the latter, we first show that also the coupling obeys such a representation. The subsequent spectral reconstruction of the coupling data, obtained from 2+1 flavour lattice QCD results for the ghost and gluon, is based on a probabilistic inversion of this representation using Gaussian process regression with analytically enforced asymptotics. In contradistinction, our direct calculation relies on earlier reconstruction results for the ghost and gluon spectral functions themselves, as well as data obtained in functional QCD. Apart from its relevance for studies of resonances or scattering processes, the calculation also serves as a non-trivial benchmark of our reconstruction approach. The results show remarkable agreement, testifying to the reliability of the method., 13 pages, 6 figures

41st International Conference on High Energy Physics, ICHEP2022, Bologna, Italy, 6 Jul 2022 - 13 Jul 2022; Proceedings of Science / International School for Advanced Studies (ICHEP2022), 823 (2022). doi:10.22323/1.414.0823, The energy dependency (running) of the strength of electromagnetic interactions $\alpha$ plays an important role in precision tests of the SM. The running of the former to the Z pole is an input quantity for global electroweak fits, while the running of the mixing angle is susceptible to the effects of BSM physics, particularly at low energies. We present a computation of the hadronic vacuum polarization (HVP) contribution to the running of these electroweak couplings at the non-perturbative level in lattice QCD, in the space-like regime up to $Q^2$ momentum transfers of 7 $\text{GeV}^2$. This quantity is also closely related to the HVP contribution to the muon $g−2$. We observe a tension of up to 3.5 standard deviation between our lattice results for $\Delta\alpha^{(5)}_{\text{had}}(−Q^{2})$ and estimates based on the R-ratio for $Q^2$ in the 3 to 7 $\text{GeV}^2$ range. The tension is, however, strongly diminished when translating our result to the Z pole, by employing the Euclidean split technique and perturbative QCD, which yields $\Delta\alpha^{(5)}_{\text{had}}(M_{Z}^{2}) = 0.027\,73(15)$. This value agrees with results based on the R-ratio within the quoted uncertainties, and can be used as an alternative to the latter in global electroweak fits., Published by SISSA, Trieste

We provide a survey of recent studies of supergroup gauge theory. We first discuss supermatrix model as a zero-dimensional toy model of supergroup gauge theory and its geometric and algebraic characterization. We then focus on four-dimensional Yang--Mills theory with supergroup gauge symmetry and explore its non-perturbative properties, including instanton calculus, Seiberg-Witten geometry, Bethe/gauge correspondence, and its realization with intersecting defects., Comment: 78 pages, invited review; typos corrected, refs added

We describe three previously unnoticed components of the moduli space of minimally supersymmetric string theories in $d\geq 7$, describing in some detail their spectrum and duality properties. We find a new component in nine and eight dimensions, and two additional ones in seven dimensions. These theories were originally discovered in a bottom-up classification of possible F/M-theory singularity freezing patterns in the K3 lattice, described in a companion paper. The 9d/8d component can be understood as F/M-theory on a twisted fibration of the Klein bottle over a circle, while the new seven-dimensional components are described as IIB on Bieberbach manifolds with a duality bundle and RR-NSNS backgrounds turned on. All the new components can be obtained from previously known theories by turning on certain discrete theta angles; however, the spectrum of massive objects is very different, and most strikingly, they feature an incomplete lattice of BPS strings, showing that string BPS completeness is not true in general even with sixteen supercharges. In all cases we find non-BPS representatives for each value of the charge, so the Completeness Principle is satisfied. We also analyze analogous theta angles in nonsupersymmetric string theories, and provide a detailed explanation of why the Type I discrete $\theta$ angle proposed in 1304.1551 is unphysical, using this to clarify certain non-perturbative phenomena in $O8$ planes., Comment: 45 pages + references, 4 figures, and 3 new string theories

Journal of high energy physics 07(7), 046 (2021). doi:10.1007/JHEP07(2021)046, Published by SISSA, [Trieste]

Astronomische Nachrichten 342(5), 715 - 726 (2021). doi:10.1002/asna.202113988, We review the properties of the strongly interacting quark-gluon plasma (QGP) at finite temperature and baryon chemical potential as created in heavy-ion collisions at ultrarelativistic energies. The description of the strongly interacting (non-perturbative) QGP in equilibrium is based on the effective propagators and couplings from the Dynamical QuasiParticle Model (DQPM) that is matched to reproduce the equation-of-state of the partonic system above the deconfinement temperature from lattice QCD. Based on a microscopic transport description of heavy-ion collisions, we discuss which observables are sensitive to the QGP creation and its properties., Published by Wiley-VCH Verl., Berlin

We present a novel study on the inclusive production of a heavy quarkonium ($J/\psi$ or $\Upsilon$), in association with a light-flavored jet, as a test field of the high-energy QCD dynamics. The large transverse momenta at which the two final-state objects are detected permits us to perform an analysis in the spirit of the variable-flavor number scheme (VFNS), in which the cross section for the hadroproduction of a light parton is convoluted with a perturbative fragmentation function that describes the transition from a light quark to a heavy hadron. The quarkonium collinear fragmentation function is built as a product between a short-distance coefficient function, which encodes the resummation of DGLAP type logarithms, and a non-perturbative long-distance matrix element (LDME), calculated in the non-relativistic QCD (NRQCD) framework. Our theoretical setup is the hybrid high-energy and collinear factorization, where the standard collinear approach is supplemented by the resummation of leading and next-to-leading energy-type logarithms \emph{\`a la} BFKL. We propose this reaction as a suitable channel to probe the production mechanisms of quarkonia at high energies and large transverse momenta and to possibly unveil the transition region from the heavy-quark pair production mechanism to the single-parton fragmentation one., Comment: 11 pages, 2 figures. Presented by M. Fucilla at DIS2022: XXIX International Workshop on Deep-Inelastic Scattering and Related Subjects, Santiago de Compostela, Spain, May 2-6 2022

We present a radically new proposal for the solution of the naturalness/hierarchy problem, where the fine-tuning of the Higgs mass finds its physical explanation and the well-known multiplicative renormalization of the usual perturbative approach emerges as an IR property of the non-perturbative running of the mass., 7 pages, 4 figures

We consider strong 't Hooft coupling expansion in special four-dimensional $\mathcal N=2$ superconformal models that are planar-equivalent to $\mathcal N=4$ super Yang-Mills theory. Various observables in these models that admit localization matrix model representation can be expressed at large $N$ in terms of a Fredholm determinant of a Bessel operator. The latter previously appeared in the study of level spacing distributions in matrix models and, more recently, in four-point correlation functions of infinitely heavy half-BPS operators in planar $\mathcal N=4$ SYM. We use this relation and a suitably generalized Szego-Akhiezer-Kac formula to derive the strong 't Hooft coupling expansion of the leading corrections to free energy, half-BPS circular Wilson loop, and certain correlators of chiral primaries operators in the $\mathcal N=2$ models. This substantially generalizes partial results in the literature and represents a challenge for dual string theory calculations in AdS/CFT context. We also demonstrate that the resulting strong-coupling expansions suffer from Borel singularities and require adding non-perturbative, exponentially suppressed corrections. As a byproduct of our analysis, we determine the non-perturbative correction to the above mentioned four-point correlator in planar $\mathcal N=4$ SYM., 65 pages. v2: misprints and eq.(4.20) corrected, note added; v3: minor clarifications

The operator definition of generalised transverse-momentum-dependent (GTMD) distributions is exploited to compute for the first time the full set of one-loop corrections to the off-forward matching functions. These functions allow one to obtain GTMDs in the perturbative regime in terms of generalised parton distributions (GPDs). In the unpolarised case, non-perturbative corrections can be incorporated using recent determinations of transverse-momentum-dependent (TMD) distributions. Evolution effects for GTMDs closely follow those for TMDs and can thus be easily accounted for up to next-to-next-to-leading logarithmic accuracy. As a by-product, the relevant one-loop anomalous dimensions are derived, confirming previous results. As a practical application, numerical results for a specific kind of GTMDs are presented, highlighting some salient features., 28 pages including references, 6 figures, accompanied by a code to reproduce the numerical results

We are very grateful to the Fermilab Directorate and the Fermilab Theoretical Physics Department for their financial and logistical support of the first workshop of the Muon g -2 Theory Initiative (held near Fermilab in June 2017) [123], which was crucial for its success, and indeed for the successful start of the Initiative. Financial support for this workshop was also provided by the Fermilab Distinguished Scholars program, the Universities Research Association through a URA Visiting Scholar award, the Riken Brookhaven Research Center, and the Japan Society for the Promotion of Science under Grant No. KAKEHNHI-17H02906. We thank Shoji Hashimoto, Toru Iijima, Takashi Kaneko, and Shohei Nishida for hosting the HVP workshop at KEK [124] and the KEK Theory Center and the U.S.-Japan Science and Technology Cooperation Program in High Energy Physics for providing logistical and financial support. The HLbL workshop at the University of Connecticut [125] was hosted by the University of Connecticut Physics Department. We also gratefully acknowledge support for the second plenary workshop in Mainz [126] from the Deutsche Forschungsgemeinschaft via the Cluster of Excellence "Precision Physics, Fundamental Interactions and Structure of Matter'' (PRISMA), the Collaborative Research Centre "The low-energy frontier of the Standard Model'' (SFB 1044), as well as the Helmholtz Institute Mainz. And finally, we thank the Institute for Nuclear Theory at the University of Washington for hosting the third plenary workshop [127] and for its kind hospitality and stimulating research environment. This workshop was supported in part by the U.S. Department of Energy, Office of Science, under Award Nos. DE-FG02-00ER41132, DE-SC0020106, and by the U.S.-Japan Science and Technology Cooperation Program in High Energy Physics. This review benefited from discussions with O. Cata, N. Christ, L.Y. Dai, H. Davoudiasl, S. Fayer, S. Ganguly, A. Gasparian, S. Hashimoto, T. Iijima, K. Kampf, D. Kawall, I. Larin, Z. Pagel, M. Petschlies, A. Rebhan, K. Schilcher, K. Shimomura, E. Shintani, D. Steffen, S. Tracz, C. Tu, and T. Yamazaki. The work in this paper was supported by CNRS, by Conacyt (Ciencia Basica 2015) under Grant No. 250628, by CONACyT-Mexico under Grant No. CB2014-22117, by Coordinacion de la Investigacion Cientifica (CIC-UMSNH) under Grant No. 4.10, by Danmarks Frie Forskningsfond under Grant No. 8021-00122B, by Deutsche Forschungsgemeinschaft Collaborative Research Centers CRC 1044, CRC 1044 -204404729, CRC 110, and under Grant No. HI 2048/1-1, Prisma Cluster for Excellence PRISMA+ EXC2118/1, STO/876/6-1, by European Research Council under the European Union's Horizon 2020 research and innovation programme under Grant Agreement Nos. 668679, 757646, 771971-SIMDAMA, 813942, by the European Union H2020-MSCA-COFUND2016 under Grant No. 754510, by the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 843134, by European Union EuroPLEx Grant H2020-MSCA-ITN-2018-813942, by European Union STRONG 2020 project under Grant Agreement No. 824093, by the Excellence Initiative of Aix-Marseille University -A*MIDEX, a French "Investissements d'Avenir" program, through the Chaire d'Excellence program and the OCEVU Laboratoire d'Excellence (ANR-11-LABX-0060), by the Fermilab Distinguished Scholars program, by Fondo SEP-Cinvestav under Grant No. 142, Fundacao para a Ciencia e a Tecnologia under Grant No. SFRH/BPD/109443/2015, by Generalitat de Catalunya under Grant No. 2017SGR1069, by the Helmholtz Association (German Federal Ministry of Education and Research), by the Helmholtz-Institut Mainz, by the Istituto Nazionale di Fisica Nucleare (INFN), by the Isaac Newton Trust, by the Japan Society for the Promotion of Science under Grant Nos. KAKENHI-15H05742, 16K05317, 16K05323, 16K05338, 17H01133, 17H02906, 18H05226, 19K21872, 20K03926, 20K03960, by Junta de Andalucia under Grant No. A-FQM-467-UGR18, by KEK, by Ministerio de Ciencia e Innovacion under Grant No. CICYTFEDER-FPA2017-86989-P, by Ministerio de Industria, Economia y Competitividad under Grant Nos. FPA2016-78220-C3-3-P, FPA2017-86989-P, PGC2018-094857-B-I00, SEV-2016-0588, SEV-2016-0597, by Laboratoires d'Excellence FIRST-TF grants, a French "Investissements d'Avenir'' program, by the Ministry of Science and Higher Education of the Russian Federation under Grant Agreement No. 14.W03.31.0026, by the National Research Foundation of South Africa, by the Natural Sciences and Engineering Research Council of Canada, by the Portuguese Science Foundation (FCT) Investigator Grant IF/00898/2015, by the Romanian Ministry of Education and Research under Grant No. PN19060101, by the Russian Science Foundation under Grant No. RSF 18-12-00128, by the Secretaria d'Universitats i Recerca del Departament d'Economia i Coneixement de la Generalitat de Catalunya under Grant No. 2017 SGR 1069, by the Swedish Research Council under Grant Nos. 2016-05996, 2019-03779, by the Swiss National Science Foundation under Grant Nos. PP00P2_176884, PCEFP2_181117, by The Leverhulme Trust under Grant No. ECF-2019-223, by the UK Science and Technology Facilities Council (STFC) under Grant Nos. ST/N504130/1, ST/P000290/1, ST/P00055X/1, ST/P000630/1, ST/P000711/1, ST/P000746/1, ST/S000879/1, ST/S000925/1, by the U.S. Department of Energy, Office of Science, Office of High Energy Physics under Award Nos. DE-SC0009919, DE-SC0009998, DE-SC0010005, DE-SC0010120, DE-SC0010339, DE-SC0012391, DE-SC0012704, DE-SC0013682, DE-SC0013895, DE-SC0015655, by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under Award Nos. DE-AC02-05CH11231, DE-FG02-00ER41132, DE-FG02-97ER41020, by the U.S.-Japan Science and Technology Cooperation Program in High Energy Physics, "Incubation Platform for Intensity Frontier", by the U.S. National Science Foundation under Grant Nos. NSF-PHY-1316222, PHY14-14614, PHY17-19626, and PHY19-23131, and by the U.S. National Institute of Standards and Technology (NIST) Precision Measurement Grant Program under Award No. 60NANB16D271. This manuscript has been authored by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics., We review the present status of the Standard Model calculation of the anomalous magnetic moment of the muon. This is performed in a perturbative expansion in the fine-structure constant and is broken down into pure QED, electroweak, and hadronic contributions. The pure QED contribution is by far the largest and has been evaluated up to and including with negligible numerical uncertainty. The electroweak contribution is suppressed by and only shows up at the level of the seventh significant digit. It has been evaluated up to two loops and is known to better than one percent. Hadronic contributions are the most difficult to calculate and are responsible for almost all of the theoretical uncertainty. The leading hadronic contribution appears at and is due to hadronic vacuum polarization, whereas at the hadronic light-by-light scattering contribution appears. Given the low characteristic scale of this observable, these contributions have to be calculated with nonperturbative methods, in particular, dispersion relations and the lattice approach to QCD. The largest part of this review is dedicated to a detailed account of recent efforts to improve the calculation of these two contributions with either a data-driven, dispersive approach, or a first-principle, lattice-QCD approach. The final result reads and is smaller than the Brookhaven measurement by 3.7. The experimental uncertainty will soon be reduced by up to a factor four by the new experiment currently running at Fermilab, and also by the future J-PARC experiment. This and the prospects to further reduce the theoretical uncertainty in the near future – which are also discussed here – make this quantity one of the most promising places to look for evidence of new physics., Fermilab Directorate, Fermilab Theoretical Physics Department, Fermilab Distinguished Scholars program, Universities Research Association through a URA Visiting Scholar award, Riken Brookhaven Research Center, Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT) Japan Society for the Promotion of Science KAKEHNHI-17H02906 KAKENHI-15H05742 16K05317 16K05323 16K05338 17H01133 17H02906 18H05226 19K21872 20K03926 20K03960, High Energy Accelerator Research Organization (KEK), U.S.-Japan Science and Technology Cooperation Program in High Energy Physics, Deutsche Forschungsgemeinschaft via the Cluster of Excellence "Precision Physics, Fundamental Interactions and Structure of Matter'' (PRISMA), Collaborative Research Centre "The low-energy frontier of the Standard Model'' SFB 1044, Helmholtz Institute Mainz, United States Department of Energy (DOE) DE-FG02-00ER41132 DE-SC0020106, Centre National de la Recherche Scientifique (CNRS), Conacyt (Ciencia Basica 2015) 250628, Consejo Nacional de Ciencia y Tecnologia (CONACyT) CB2014-22117, Coordinacion de la Investigacion Cientifica (CIC-UMSNH) 4.10, Danmarks Frie Forskningsfond 8021-00122B, German Research Foundation (DFG) CRC 1044 CRC 1044 -204404729 CRC 110 HI 2048/1-1, Prisma Cluster for Excellence PRISMA+ EXC2118/1 STO/876/6-1, European Research Council (ERC) 668679 757646 771971-SIMDAMA 813942, European Union (EU) 754510, European Union (EU) 843134, European Union EuroPLEx Grant H2020-MSCA-ITN-2018-813942, European Union STRONG 2020 project 824093, French National Research Agency (ANR), OCEVU Laboratoire d'Excellence ANR-11-LABX-0060, Fondo SEP-Cinvestav 142, Portuguese Foundation for Science and Technology SFRH/BPD/109443/2015, Generalitat de Catalunya 2017SGR1069, Helmholtz Association (German Federal Ministry of Education and Research), Istituto Nazionale di Fisica Nucleare (INFN), Isaac Newton Trust, Junta de Andalucia A-FQM-467-UGR18, Instituto de Salud Carlos III Spanish Government CICYTFEDER-FPA2017-86989-P, Ministerio de Industria, Economia y Competitividad FPA2016-78220-C3-3-P FPA2017-86989-P PGC2018-094857-B-I00 SEV-2016-0588 SEV-2016-0597, Laboratoires d'Excellence FIRST-TF grants, Ministry of Science and Higher Education of the Russian Federation 14.W03.31.0026, National Research Foundation - South Africa, Natural Sciences and Engineering Research Council of Canada (NSERC) CGIAR, Portuguese Science Foundation (FCT) Investigator Grant IF/00898/2015, Romanian Ministry of Education and Research PN19060101, Russian Science Foundation (RSF) RSF 18-12-00128, Generalitat de Catalunya 2017 SGR 1069, Swedish Research Council 2016-05996 2019-03779, Swiss National Science Foundation (SNSF) PP00P2_176884 PCEFP2_181117, Leverhulme Trust ECF-2019-223, UK Research & Innovation (UKRI) Science & Technology Facilities Council (STFC) ST/N504130/1 ST/P000290/1 ST/P00055X/1 ST/P000630/1 ST/P000711/1 ST/P000746/1 ST/S000879/1 ST/S000925/1, United States Department of Energy (DOE) DE-SC0009919 DE-SC0009998 DE-SC0010005 DE-SC0010120 DE-SC0010339 DE-SC0012391 DE-SC0012704 DE-SC0013682 DE-SC0013895 DE-SC0015655, United States Department of Energy (DOE) DE-FG02-00ER41132 DE-AC02-05CH11231 DE-FG02-97ER41020 DE-AC02-07CH11359, U.S.-Japan Science and Technology Cooperation Program in High Energy Physics, "Incubation Platform for Intensity Frontier", National Science Foundation (NSF) NSF-PHY-1316222 PHY14-14614 PHY17-19626 PHY19-23131, U.S. National Institute of Standards and Technology (NIST) Precision Measurement Grant 60NANB16D271

We compute resummed and matched predictions for jet angularities in hadronic dijet and Z+jet events with and without grooming the candidate jets using the SoftDrop technique. Our theoretical predictions also account for non-perturbative corrections from the underlying event and hadronisation through parton-to-hadron level transfer matrices extracted from dedicated Monte Carlo simulations with SHERPA. Thanks to this approach we can account for non-perturbative migration effects in both the angularities and the jet transverse momentum. We compare our predictions against recent measurements from the CMS experiment. This allows us to test the description of quark- and gluon-jet enriched phase-space regions separately. We supplement our study with SHERPA results based on the matching of NLO QCD matrix elements with the parton shower. Both theoretical predictions offer a good description of the data, within the experimental and theoretical uncertainties. The latter are however sizeable, motivating higher-accuracy calculations., Comment: 32 pages, 16 figures, extended discussion of uncertainties and included string model for hadronisation, added additional result as ancillary files, minor additional clarifications and text editing, version accepted for publication in JHEP

We investigate the massive Schwinger model in $d=1+1$ dimensions using bosonization and the nonperturbative functional renormalization group. In agreement with previous studies we find that the phase transition, driven by a change of the ratio $m/e$ between the mass and the charge of the fermions, belongs to the two-dimensional Ising universality class. The temperature and vacuum angle dependence of various physical quantities (chiral density, electric field, entropy density) are also determined and agree with results obtained from density matrix renormalization group studies. Screening of fractional charges and deconfinement occur only at infinite temperature. Our results exemplify the possibility to obtain virtually all physical properties of an interacting system from the functional renormalization group., 14 pages, 9 figures

We continue our study of strongly-coupled, approximately scale-invariant gauge theories with a large number of flavours, which provide a suitable ultraviolet completion of the composite-Higgs scenario. We identify the requisite operators to realise partial compositeness of the Standard-Model fermions. In order to compute the spectrum of composite fermionic states, we extend the bottom-up holographic models, which we previously introduced to capture the main features of the non-perturbative dynamics in the Veneziano limit, by adding fermion fields in the bulk. We identify regions in parameter space where some fermionic bound states become light, depending in particular on the number of flavours, the operator scaling dimensions, and the bulk Yukawa couplings. We also observe a dense spectrum of states, when multi-scale dynamics is induced by a large backreaction of bulk scalars on the geometry. Adapting the formalism of the holographic Wilsonian renormalisation group, we study the linear coupling between the composite and elementary fermions, as a function of energy scale. We find that, in some circumstances, the associated operators are dangerously irrelevant: the renormalisation-group flow gives rise to a large linear coupling in the infrared, even when it is irrelevant from the point of view of the ultraviolet fixed point. We finally compute the partially composite spectrum, correlate it with the analysis of the flow, and assess the potential phenomenological implications, e.g. for the top-quark partners.

We discuss the construction of the two-flavour axion-pion effective Lagrangian at the next-to-leading order (NLO) in chiral perturbation theory and present two phenomenological applications: the scattering $a\pi \to \pi\pi$, relevant for axion thermalization in the early Universe, and the decay rate of a GeV-scale axion-like particle via the channel $a \to \pi\pi\pi$. In both cases we assess, through the NLO computation, the range of validity of the effective field theory and show that the chiral expansion breaks down earlier than what previously assumed. These results call for alternative non-perturbative approaches in order to extend the chiral description of axion-pion interactions.

We study 2-to-2 scattering amplitudes of massless spin one particles in $d=4$ space-time dimensions, like real world photons. We define a set of non-perturbative observables (Wilson coefficients) which describe these amplitudes at low energies. We use full non-linear unitarity to construct various novel numerical bounds on these observables. For completeness, we also rederive some bounds using positivity only. We discover and explain why some of these Wilson coefficients cannot be bounded., Comment: 39 pages + appendices, 20 figures

We present the results of the application of the Dispersion Matrix approach to semileptonic heavy-to-heavy and heavy-to-light $B$-meson decays. This method allows to determine the hadronic form factors in a non-perturbative and model-independent way. Starting from the available lattice results at large values of the momentum transfer, we obtain the behaviour of the form factors in their whole kinematical range without introducing any parameterization of their momentum dependence. We will focus on the determination of the Cabibbo-Kobayashi-Maskawa matrix elements $\vert V_{cb} \vert$ and $\vert V_{ub} \vert$ through the analysis of $B \to D^{(*)} \ell \nu$, $B_s \to D_s^{(*)} \ell \nu$, $B \to \pi \ell \nu$ and $B_s \to K \ell \nu$ decays. New theoretical determinations of the Lepton Flavour Universality ratios relevant for these transitions will be also presented, by focusing in particular on the $R(D_{(s)}^{(*)})$ ratios., Comment: 9 pages, 3 figures. Proceedings for the 39th International Symposium on Lattice Field Theory (Lattice 2022). arXiv admin note: substantial text overlap with arXiv:2209.15413, arXiv:2205.13952; text overlap with arXiv:2211.07236

The strong CP problem is inseparably connected with the topology of gauge fields and the mechanism of color confinement, which requires nonperturbative tools to solve it. In this talk I present results of a recent lattice investigation of QCD with the $\theta$ term in collaboration with Yoshifumi Nakamura. The tool we are using to address the nonperturbative properties of the theory is the gradient flow, which is a particular realization of momentum space RG transformations. The novel result is that within QCD the vacuum angle $\theta$ is renormalized, together with the strong coupling constant, and flows to $\theta = 0$ in the infrared limit. This means that CP is conserved by the strong interactions.

We investigate the out-of-equilibrium production of scalar dark matter (DM) from the inflaton condensate during inflation and reheating. We assume that this scalar couples only to the inflaton via a direct quartic coupling and is minimally coupled to gravity. We consider all possible production regimes: purely gravitational, weak direct coupling (perturbative), and strong direct coupling (non-perturbative). For each regime, we use different approaches to determine the dark matter phase space distribution and the corresponding relic abundance. For the purely gravitational regime, scalar dark matter quanta are copiously excited during inflation resulting in an infrared (IR) dominated distribution function and a relic abundance which overcloses the universe for a reheating temperature $T_\text{reh}>34 ~\text{GeV}$. A non-vanishing direct coupling induces an effective DM mass and suppresses the large IR modes in favor of ultraviolet (UV) modes and a minimal scalar abundance is generated when the interference between the direct and gravitational couplings is maximal. For large direct couplings, backreaction on the inflaton condensate is accounted for by using the Hartree approximation and lattice simulation techniques. Since scalar DM candidates can behave as non-cold dark matter, we estimate the impact of such species on the matter power spectrum and derive the corresponding constraints from the Lyman-$\alpha$ measurements. We find that they correspond to a lower bound on the DM mass of $\gtrsim 3\times 10^{-4} \, \rm{eV}$ for purely gravitational production, and $\gtrsim 20 \, \rm {eV}$ for direct coupling production. We discuss the implications of these results.

We study the associated production of prompt $J/\psi$ mesons and $W$ or $Z$ bosons within the factorization approach of nonrelativistic QCD (NRQCD) at next-to-leading order in $\alpha_s$, via intermediate color singlet ${^3}S_1^{[1]}$ and ${^3}P_J^{[1]}$ and color octet ${^1S}_0^{[8]}$, ${^3S}_1^{[8]}$ and ${^3P}_J^{[8]}$ states. Requiring for our predictions to be compatible with recent ATLAS measurements yields stringent new constraints on charmonium long-distance matrix elements (LDMEs) being nonperturbative, process-independent input parameters. Considering four popular LDME sets fitted to data of single $J/\psi$ inclusive production, we find that one is marginally compatible with the data, with central predictions typically falling short by a factor of three, one is unfavored, the factor of shortfall being about one order of magnitude, and two violate cross section positivity for direct $J/\psi+W/Z$ production. The large rate of prompt $J/\psi$ plus $W$ production observed by ATLAS provides strong evidence for the color octet mechanism inherent to NRQCD factorization, the leading color singlet contribution entering only at $\mathcal{O}(G_F\alpha_s^4)$, beyond the order considered here.

We propose to use quantum information notions to characterize thermally induced melting of nonperturbative bound states at high temperatures. We apply tensor networks to investigate this idea in static and dynamical settings within the Ising quantum field theory, where bound states are confined fermion pairs - mesons. In equilibrium, we identify the transition from an exponential decay to a power law scaling with temperature in an efficiently computable second Renyi entropy of a thermal density matrix as a signature of meson melting. Out of equilibrium, we identify as the relevant signature the transition from an oscillatory to a linear growing behavior of reflected entropy after a thermal quench. These analyses apply more broadly, which brings new ways of describing in-medium meson phenomena in quantum many-body and high-energy physics.

It is generally believed that global symmetries, in particular axion shift symmetries, can only be approximate. This motivates us to quantify the breaking of the shift invariance that characterizes the couplings of an axion-like particle (ALP), and to identify proper order parameters associated to this breaking. Focusing on the flavorful effective Yukawa couplings to Standard Model fermions, we work out explicit conditions for them to maintain an exact axion shift symmetry. Those conditions are given in terms of Jarlskog-like flavor-invariants and can be directly evaluated from the values of the different Yukawa couplings. Therefore, they represent order parameters for the breaking of the axion shift symmetry. We illustrate this constrution by matching the axion EFT to UV models, and by showing that the renormalization group running closes on those shift-breaking flavor-invariants, as it should on any complete set of order parameters. Furthermore, the study of the invariants' CP-parities indicate that all but one are CP-odd, hence the assumption of CP conservation suffices to cancel all but one sources of shift-breaking in the theory. We also investigate similar conditions in the low-energy EFT below the electroweak scale, and comment on relations inherited from a UV completion which realizes the electroweak symmetry linearly. Finally, we discuss the order parameter associated to the non-perturbative shift-breaking induced by the axion-gluons coupling, which is also flavorful.

The European physical journal / C 82(12), 1092 (2022). doi:10.1140/epjc/s10052-022-10998-3, We present the details and first results of a new strategy for the determination of $\alpha _s(m_Z)$ (ALPHA Collaboration et al. in Phys. Lett. B 807:135571, 2020). By simultaneously decoupling 3 fictitious heavy quarks we establish a relation between the $\Lambda $-parameters of three-flavor QCD and pure gauge theory. Very precise recent results in the pure gauge theory (Dalla Brida and Ramos in Eur. Phys. J. C 79(8):720, 2019; Nada and Ramos in Eur Phys J C 81(1):1, 2021) can thus be leveraged to obtain the three-flavour $\Lambda $-parameter in units of a common decoupling scale. Connecting this scale to hadronic physics in 3-flavour QCD leads to our result in physical units, $\Lambda ^{(3)}_{\overline{\textrm{MS}}} = 336(12)\, {\textrm{MeV}}$, which translates to $\alpha _s(m_Z) = 0.11823(84)$. This is compatible with both the FLAG average (Aoki et al. in FLAG review 2021. arXiv:2111.09849 [hep-lat]) and the previous ALPHA result (ALPHA Collaboration et al., Phys. Rev. Lett. 119(10):102001, 2017), with a comparable, yet still statistics dominated, error. This constitutes a highly non-trivial check, as the decoupling strategy is conceptually very different from the 3-flavour QCD step-scaling method, and so are their systematic errors. These include the uncertainties of the combined decoupling and continuum limits, which we discuss in some detail. We also quantify the correlation between both results, due to some common elements, such as the scale determination in physical units and the definition of the energy scale where we apply decoupling., Published by Springer, Heidelberg

Hadronic light-by-light scattering is one of the virtual processes that causes the gyromagnetic factor $g$ of the muon to deviate from the value of two predicted by Dirac's theory. This process makes one of the largest contributions to the uncertainty of the Standard Model prediction for the muon $(g-2)$. Lattice QCD allows for a first-principles approach to computing this non-perturbative effect. In order to avoid power-law finite-size artifacts generated by virtual photons in lattice simulations, we follow a coordinate-space approach involving a weighted integral over the vertices of the QCD four-point function of the electromagnetic current carried by the quarks. Here we present in detail the semi-analytical calculation of the QED part of the amplitude, employing position-space perturbation theory in continuous, infinite four-dimensional Euclidean space. We also provide some useful information about a computer code for the numerical implementation of our approach that has been made public at https://github.com/RJHudspith/KQED., Comment: 84 pages, 13 figures; text matches the published version

The production of quarkonia in hadronic collisions provides a unique testing ground for understanding quantum chromodynamics (QCD) since it involves both the perturbative and non-perturbative regimes of this theory. Given that a satisfactory description of quarkonia production has not yet been achieved, new measurements that can provide new insights, helping to constrain models, are needed. The ALICE apparatus allows to measure inclusive J/$\psi$ production, as well as to separate prompt charmonia from those originating from b-hadron decays. The study of the azimuthal correlation of the emitted particles, e.g. via the measurement of the elliptic flow ($v_2$), in high multiplicity proton-proton (pp) collisions can probe collective behaviour in small systems. In this contribution, we present new measurements of the inclusive, prompt and non-prompt J/$\psi$ production in pp collisions at different collision energies, together with the J/$\psi$ $v_2$ in high multiplicity pp collisions at $\sqrt{s}$=13 TeV., Comment: 6 pages, 3 figures. 41st International Conference on High Energy physics - ICHEP2022, Bologna, Italy, 6-13 July, 2022

Beam-recoil transferred polarizations for the exclusive electroproduction of $K^+\Lambda$ and $K^+\Sigma^0$ final states from an unpolarized proton target have been measured using the CLAS12 spectrometer at Jefferson Laboratory. The measurements at beam energies of 6.535~GeV and 7.546~GeV span the range of four-momentum transfer $Q^2$ from 0.3 to 4.5~GeV$^2$ and invariant energy $W$ from 1.6 to 2.4~GeV, while covering the full center-of-mass angular range of the $K^+$. These new data extend the existing hyperon polarization data from CLAS in a similar kinematic range but from a significantly larger dataset. They represent an important addition to the world data, allowing for better exploration of the reaction mechanism in strangeness production processes, for further understanding of the spectrum and structure of excited nucleon states, and for improved insight into the strong interaction in the regime of non-perturbative dynamics., Comment: 25 pages, 22 figures, 4 tables

Journal of high energy physics 08(8), 067 (2022). doi:10.1007/JHEP08(2022)067, We study multipoint correlators of protected scalars on the Maldacena-Wilson line in $ \mathcal{N} $ = 4 SYM. Working at weak coupling in the planar limit, we derive an explicit recursion relation that captures next-to-leading order correlators with an arbitrary number of insertions of the fundamental scalar field. By pinching fundamental scalars together, we can build composite protected operators with higher values of the R-charge. Our result then encompasses arbitrary n-point correlators of protected operators with arbitrary weight. As a demonstration of our method, we give explicit formulae for correlators with up to six points. Using these results we observe that all our correlators are annihilated by a special class of differential operators. We conjecture that these differential operators are non-perturbative constraints and can be considered a multipoint extension of the superconformal Ward identities satisfied by four-point functions., Published by SISSA, [Trieste]

Connecting the Dots Workshop, CTD 2022, New Jersey, USA, 31 May 2022 - 2 Jun 2022; 7 pp. (2022)., LUXE (Laser Und XFEL Experiment) is a proposed experiment at DESY which will study Quantum Electrodynamics (QED) in the strong-field regime, where QED becomes non-perturbative. The measurement of the rate of electron-positron pair creation, an essential ingredient to study this regime, is enabled by the use of a silicon tracking detector. Precision tracking of positrons traversing the four layers of the tracking detector becomes very challenging at high laser intensities due to the high rates, which can be computationally expensive for classical computers. In this work, an update of our previous studies of the potential of quantum computers to reconstruct positron tracks is presented. The reconstruction problem is formulated in terms of a Quadratic Unconstrained Binary Optimisation (QUBO), and solved using simulated quantum computers and a hybrid quantum-classical algorithm, namely Variational Quantum Eigensolver (VQE). Different ansatz circuits and optimisers are studied. The results are discussed and compared with classical track reconstruction algorithms using Graph Neural Network and Combinatorial Kalman Filter.