Related papers: Lattice Simulations and Effective Theories
We report on the status of an ALPHA Collaboration project to extract quantities for B physics phenomenology from Nf=2 lattice simulations. The framework is Heavy Quark Effective Theory (HQET) expanded up to the first order of the inverse…
We determine the normalisation of scalar and pseudoscalar current operators made from non-relativistic $b$ quarks and Highly Improved Staggered light quarks in lattice Quantum Chromodynamics (QCD) through $\mathcal{O}(\alpha_s)$ and…
We calculate the B-meson decay constants f_B, f_Bs, and their ratio in unquenched lattice QCD using domain-wall light quarks and relativistic b-quarks. We use gauge-field ensembles generated by the RBC and UKQCD collaborations using the…
We present a high statistics study of the leptonic decay constant $f_P$ of heavy pseudoscalar mesons using propagating heavy Wilson quarks within the quenched approximation, on lattices covering sizes from about 0.7~fm to 2~fm. Varying…
We present the first lattice QCD calculation of the decay constants f_B and f_{B_s} with physical light quark masses. We use configurations generated by the MILC collaboration including the effect of u, d, s and c HISQ sea quarks at three…
We formulate the lattice QCD simulation with background classical gravitational fields. This formulation enables us to study nonperturbative aspects of quantum phenomena in curved spacetimes from the first principles. As the first…
The lattice formulation provides a way to regularize, define and compute the Path Integral in a Quantum Field Theory. In this paper we review the theoretical foundations and the most basic algorithms required to implement a typical lattice…
After many years of development of the basic tools, quantum simulation with ultracold atoms has now reached the level of maturity where it can be used to investigate complex quantum processes. Planning of new experiments and upgrading…
A real-space formalism for density-functional perturbation theory (DFPT) is derived and applied for the computation of harmonic vibrational properties in molecules and solids. The practical implementation using numeric atom-centered…
Technicolor theories provide an elegant mechanism for dynamical electroweak symmetry breaking. We will discuss the use of lattice simulations to study the strongly-interacting dynamics of some of the candidate theories, with matter fields…
In this contribution we give an introduction to the foundations and methods of lattice gauge theory. Starting with a brief discussion of the quantum mechanical path integral, we develop the main ingredients of lattice field theory:…
We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle physics community. More specifically, we report on the determination of the light-quark masses, the form…
Several UV complete models of physics beyond the Standard Model are currently under scrutiny, their low-energy dynamics being compared with the experimental data from the LHC. Lattice simulations can play a role in these studies by…
We discuss the successes and limitations of statistical sampling for a sequence of models studied in the context of lattice QCD and emphasize the need for new methods to deal with finite-density and real-time evolution. We show that these…
We present results for the B_s meson decay constant f_{B_s} from simulations at three lattice spacings in the range a^{-1}=1.1 to 2.6 GeV using NRQCD heavy quarks and clover light quarks in the quenched approximation. We study scaling of…
We present a short review of our most recent high statistics lattice determinations in the HQET of the following important parameters in B physics: the B--meson binding energy, $\overline{\Lambda}$ and the kinetic energy of the b quark in…
During the last years, the ALPHA collaboration has been developing and implementing a method based on Heavy Quark Effective Theory (HQET) to compute B-mesons observables through lattice simulations. Thanks to a non-perturbative matching to…
Heavy-light bound states are studied in Lattice QCD with emphasis on parameters of the B-system relevant to experiment. Results are obtained on lattices with lattice spacings from about 0.15 fm to 0.06 fm corresponding to $\beta=5.74, 6.0$…
We present a lattice QCD determination of the b quark mass and of the B and B_s decay constants, performed with N_f=2 twisted mass Wilson fermions, by simulating at four values of the lattice spacing. In order to study the b quark on the…
In recent years, we used lattice QCD to calculate some quantities that were unknown or poorly known. They are the $q^2$ dependence of the form factor in semileptonic $D\to Kl\nu$ decay, the leptonic decay constants of the $D^+$ and $D_s$…