Related papers: On the relation between low-energy constants and r…
The low-lying energy excitations of 2-flavour QCD in the chiral limit confined to a small spatial box ($\delta$-regime) are that of an $O(4)$ rotator. In this work, we calculate the corrections due to the presence of a nonzero quark mass up…
The relation between the chiral quark condensate in QCD sum rules and chiral perturbation theory is clarified with the help of a low-energy theorem for the scalar and pseudoscalar correlation functions. It is found that the quark condensate…
In the low energy region chiral perturbation theory including virtual photons is used to derive the structure of the generating functional. The work we do is performed within the three flavor framework and reaches up to next-to-leading…
In the framework of heavy-baryon chiral perturbation theory, we investigate the fixed point structure of renormalization group equations (RGE) for the ratios of the renormalized low energy constants (LECs) that feature in the pion-nucleon…
The non-observation of new particles at the LHC suggests the existence of a mass gap above the electroweak scale. This situation is adequately described through a general electroweak effective theory with the established fields and Standard…
The delta-regime of QCD is characterised by light quarks in a small spatial box, but a large extent in (Euclidean) time. In this setting a specific variant of chiral perturbation theory - the delta-expansion - applies, based on a quantum…
We consider the low-energy effects of a selected set of Lorentz- and CPT-violating quark and gluon operators by deriving the corresponding chiral effective lagrangian. Using this effective lagrangian, low-energy hadronic observables can be…
A microscopic framework of nuclear energy density functionals is reviewed, which establishes a direct relation between low-energy QCD and nuclear structure, synthesizing effective field theory methods and principles of density functional…
These lecture notes concern recent developments in our understanding of the low energy properties of QCD. Significant progress has been made on the lattice and the beautiful experimental results on the Ke4 and K->3pi decays, as well as…
We extract the statistical uncertainties for the pion-nucleon ($\pi N$) low energy constants (LECs) up to fourth order $\mathcal{O}(Q^4)$ in the chiral expansion of the nuclear effective Lagrangian. The LECs are optimized with respect to…
Within Resonance Chiral Theory and in the context of QCD current correlators at next-to-leading order in 1/N(C), we have analyzed the two-body form factors which include resonances as a final state . The short-distance constraints have been…
Working in a two-representation lattice gauge theory that is close to a composite Higgs model, we calculate the low-energy constant CLR which controls the contribution of the electroweak gauge bosons to the Higgs potential. In QCD, the…
We present preliminary results from our calculation of the low energy constants (LECs) of the chiral effective theory for 3, 4 and 5 color QCD with $N_f=2$ dynamical fermion flavors. We simulate with clover fermions over a range of lattice…
Recently, the development of chiral perturbation theory has allowed the generation of rigorous low energy theorems for various hadronic processes based only on the chiral invariance of the underlying QCD Lagrangian. Such techniques are…
We investigate the interplay between the (light-light quark) chiral condensate and heavy-light quark condensate induced by the QCD Kondo effect, which is described by an effective Lagrangian with four-point interactions and the mean-field…
I review some basic facts about the chiral limit of QCD. This allows to formulate an effective field theory below the chiral symmetry breaking scale, chiral perturbation theory (CHPT). I show that for threshold reactions, the spectrum of…
This presentation briefly addresses three basic issues of low-energy QCD: first, whether the Nambu-Goldstone scenario of spontaneous chiral symmetry breaking is well established; secondly, whether there is a dynamical entanglement of the…
A relativistic nuclear energy density functional is developed, guided by two important features that establish connections with chiral dynamics and the symmetry breaking pattern of low-energy QCD: a) strong scalar and vector fields related…
Taking into account the negative searches for New Physics at the LHC, electroweak effective theories are appropriate to deal with current energies. Tracks of new, higher scales can be studied through next-to leading order corrections of the…
The symmetries of the Standard Model dictate that for very low energies, where nucleon dynamics can be described in terms of a pionless effective field theory, the leading-order parity-violating nucleon-nucleon Lagrangian contains five…