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We use one-flavour QCD ($N_c=3$) as a proxy to understand $\mathcal{N}=1$ SYM. For our simulations, we use tree-level improved Wilson fermions and Symanzik improved gauge action. The hadron spectrum is obtained by using LapH smearing for different masses and simulation volumes. We also report on our efforts to increase the number of colours in our simulations, where we find that the simulations show increasing topological freezing for larger $N_c$., Comment: 9 pages, 6 figures, Proceedings of the 39th International Symposium on Lattice Field Theory, 8th-13th August 2022, Bonn, Germany

The stochastic Laplacian Heaviside (LapH) method has proven to be successful in hadronic calculations. In this work, with charm-light spectroscopy in mind, we set up and optimise the LapH procedure limiting ourselves to the evaluation of two-point mesonic correlation functions. The calculations are performed on CLS ensembles with $N_f=2+1$ Wilson-Clover fermions on a $32^3\times64$ lattice with open boundary conditions. We analyse the interplay between the LapH parameters and the boundary effects, and implement a fitting procedure to isolate excitations coming from the border., Comment: 8 pages, 5 figures, Proceedings contribution to the 39th International Symposium on Lattice Field Theory, 8th-13th August 2022, Bonn, Germany

Infectious diseases are a threat for human health with tremendous impact on our society at large. The recent COVID-19 pandemic, caused by the SARS-CoV-2, is the latest example of a highly infectious disease ravaging the world, since late 2019. It is therefore imperative to develop efficient mathematical models, able to substantially curb the damages of a pandemic by unveiling disease spreading dynamics and symmetries. This will help inform (non)-pharmaceutical prevention strategies. For the reasons above we wrote this report that goes at the heart of mathematical modelling of infectious disease diffusion by simultaneously investigating the underlying microscopic dynamics in terms of percolation models, effective description via compartmental models and the employment of temporal symmetries naturally encoded in the mathematical language of critical phenomena. Our report reviews these approaches and determines their common denominators, relevant for theoretical epidemiology and its link to important concepts in theoretical physics. We show that the different frameworks exhibit common features such as criticality and self-similarity under time rescaling. These features are naturally encoded within the unifying field theoretical approach. The latter leads to an efficient description of the time evolution of the disease via a framework in which (near) time-dilation invariance is explicitly realised. As important test of the relevance of symmetries we show how to mathematically account for observed phenomena such as multi-wave dynamics. The models presented here are of immediate relevance for different realms of scientific enquiry from medical applications to the understanding of human behaviour. Our review offers novel perspectives on how to model, capture, organise and understand epidemiological data and disease dynamics for modelling real-world phenomena., Comment: 57 pages, 40 figures. Article expanded into a review. Prepared for submission to Physics Reports

We present a study of the B spectrum performed in the framework of heavy quark effective theory expanded to next-to-leading order in 1/mb and nonperturbative in the strong coupling. Our analyses have been performed on Nf=2 lattice gauge field ensembles corresponding to three different lattice spacings and a wide range of pion masses. We obtain the Bs-meson mass and hyperfine splittings of the B- and Bs-mesons that are in good agreement with the experimental values and examine the mass difference mBs-mB as a further cross-check of our previous estimate of the b-quark mass. We also report on the mass splitting between the first excited state and the ground state in the B and Bs systems, We acknowledge partial support by the SFB/TR 9, by Grants No. HE 4517/2-1 (P. F. and J. H.) and No. HE 4517/3-1 (J. H.) of the Deutsche Forschungsgemeinschaft, by the European Community through EU Contract No. MRTN-CT-2006-035482, “FLAVIAnet,” by the Spanish Minister of Education and Science projects RyC-2011-08557 and by the Danish National Research Foundation under Grant No. DNRF:90 (M. D. M.). P. F. acknowledges financial support from the Spanish MINECO under Grants No. FPA2012-31880 and No. SEV-2012-0249 (“Centro de Excelencia Severo Ochoa” Programme). N. G. is supported by the Leverhulme trust, research Grant No. RPG-2014-118. We gratefully acknowledge the computer resources granted by the John von Neumann Institute for Computing (NIC) and provided on the supercomputer JUROPA at Jülich Supercomputing Centre (JSC) and by the Gauss Centre for Supercomputing (GCS) through the NIC on the GCS share of the supercomputer JUQUEEN at JSC, with funding by the German Federal Ministry of Education and Research (BMBF) and the German State Ministries for Research of Baden-Württemberg (MWK), Bayern (StMWFK) and Nordrhein-Westfalen (MIWF), as well as within the Distributed European Computing Initiative by the PRACE-2IP, with funding from the European Community’s Seventh Framework Programme (FP7/2007-2013) under Grant Agreement No. RI-283493, by the Grand Équipement National de Calcul Intensif at CINES in Montpellier under the allocation 2012-056808, by the HLRN in Berlin, and by NIC at DESY, Zeuthen

We report on an ongoing non-perturbative determination of the improvement coefficient of the axial current, $c_\mathrm A$, with three flavours of dynamical $\mathrm O(a)$ improved Wilson quarks and tree-level Symanzik improved gauge action. Our computations are based on simulations with the openQCD code. The improvement condition for a range of couplings is formulated with Schr\"odinger functional boundary conditions and imposed along a line of constant physics in parameter space. Our analysis involves correlation functions with boundary wave functions such that a large sensitivity to $c_\mathrm A$ can be reached by exploiting the PCAC relation with two different pseudoscalar states., Comment: 7 pages, 3 figures, presented at the 31st International Symposium on Lattice Field Theory (Lattice 2013), 29 July - 3 August 2013, Mainz, Germany

We present the first results of an ongoing effort to determine the lattice scale on the N_f=2 CLS lattice ensembles via the mass of the �� baryon. Results from different methods are compared, and various sources of systematic uncertainty are discussed., 7 pages, 4 pdf figures; talk given at LATTICE 2011, XXIX International Symposium on Lattice Field Theory, July 11-16 2011, Squaw Valley, Lake Tahoe, California

We convey an idea of the significant recent progress, which opens up good perspectives for high-precision ab-initio computations in heavy flavour physics based on lattice QCD. Rather than surveying the latest results, this contribution focuses on the concept and the challenges of fully non-perturbative computations in the B-meson sector, where the b-quark is treated within an effective theory. We outline its use to determine the b-quark mass and report on the results obtained in the quenched approximation and on the status in the two dynamical flavour theory., Comment: Contribution to the NIC-Symposium 2010, 24-25 February 2010, Juelich, Germany; 8 pages including figures, latex2e, uses nic-series.cls

Using iso-spin symmetry the quark-connected and disconnected contributions to the hadronic vacuum polarisation in a theory with N_f=2 flavours can be described as independent correlation functions, respectively. We show how this allows to use twisted boundary conditions for the connected contribution in order to improve the q^2-resolution in lattice QCD. Furthermore we derive an exact relation between the connected and the disconnected contributions at NLO in chiral perturbation theory. We discuss extensions to theories with more than 2 dynamical flavours., Comment: 7 pages, 1 figure, 1 table, Talk presented at The XXVII International Symposium on Lattice Field Theory, LATTICE 2009 - Peking University, Beijing, China / July 26 - 31, 2009

We explain how the strategy of solving renormalization problems in HQET non-perturbatively by a matching to QCD in finite volume can be implemented to include dynamical fermions. As a primary application, some elements of an HQET computation of the mass of the b-quark beyond the leading order with N_f=2 are outlined. In particular, the matching of HQET and QCD requires relativistic QCD simulations in a volume with L ~ 0.5 fm, which will serve to quantitatively determine the heavy quark mass dependence of heavy-light meson observables in the continuum limit of finite-volume two-flavour lattice QCD. As a preparation for the latter, we report on our determination of the renormalization constants and improvement coefficients relating the renormalized current and subtracted bare quark mass in the relevant weak coupling region. The calculation of these coefficients employs a constant physics condition in the Schroedinger functional scheme, where the box size L is fixed by working at a prescribed value of the renormalized coupling., Comment: 14 pages including figures and tables, latex2e, uses PoS.cls; presented at the XXV International Symposium on Lattice Field Theory, July 30 - August 4 2007, Regensburg, Germany; typo corrected, results unchanged