102 citations · 1k across the 46 of their papers we have counts for
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Tetraquarks in AdS/QCD
Hilmar Forkel
Multiquark correlations inside hadrons can have a significant and in some cases even striking impact on the hadron spectrum. We show how such correlations in general, and mesons wi…
Vacuum structure and string tension in Yang-Mills dimeron ensembles
Falk Zimmermann, Hilmar Forkel, Michael Muller-Preussker
We numerically simulate ensembles of SU(2) Yang-Mills dimeron solutions with a statistical weight determined by the classical action and perform a comprehensive analysis of their p…
Multiquark correlations in light mesons and baryons from holographic QCD
Hilmar Forkel
A hadron's multiquark content reflects itself in the quark composition of the interpolator with which it has maximal overlap. The AdS/CFT dictionary translates the anomalous dimens…
Light scalar tetraquarks from a holographic perspective
Hilmar Forkel
We discuss how a dominant tetraquark component of the lightest scalar mesons may emerge in AdS/QCD gravity duals. In particular, we show that the exceptionally strong binding requi…
Hadrons as holograms
Hilmar Forkel
We review our recent work on four topics in strong-interaction physics from the perspective of the gauge/gravity correspondence. In particular, we discuss (i) the construction of t…
AdS/QCD at the correlator level
Hilmar Forkel
We derive and analyze predictions of both the hard-wall and dilaton soft-wall AdS/QCD approximations for the scalar glueball correlator and decay constants. We confront the results…
Diquark correlations in baryon spectroscopy and holographic QCD
Hilmar Forkel, Eberhard Klempt
We introduce an improved mass formula for the nucleon and delta resonances and show how it emerges from AdS/QCD in a straightforward extension of the 'metric soft wall' gravity dua…
Solution of the 5D Einstein equations in a dilaton background model
W. de Paula, T. Frederico, H. Forkel +1
We obtain an explicit solution of the 5d Einstein equations in a dilaton background model. We demonstrate that for each metric ansatz that only depends on the extra coordinate, it…
Glueball correlators as holograms
Hilmar Forkel
We investigate the dynamical content of both hard- and soft-wall approximations to holographic QCD by deriving the corresponding glueball correlation functions and by confronting t…
Dynamical holographic QCD with area-law confinement and linear Regge trajectories
W. de Paula, T. Frederico, H. Forkel +1
We construct a new solution of five-dimensional gravity coupled to a dilaton which encodes essential features of holographic QCD backgrounds dynamically. In particular, it implemen…
Holographic glueball structure
Hilmar Forkel
We derive and systematically analyze scalar glueball correlation functions in both the hard-wall and dilaton soft-wall approximations to holographic QCD. The dynamical content of t…
Linear meson and baryon trajectories in AdS/QCD
Hilmar Forkel, Michael Beyer, Tobias Frederico
An approximate holographic dual of QCD is constructed and shown to reproduce the empirical linear trajectories of universal slope on which the square masses of radially and orbital…
Linear square-mass trajectories of radially and orbitally excited hadrons in holographic QCD
Hilmar Forkel, Michael Beyer, Tobias Frederico
We consider a new approach towards constructing approximate holographic duals of QCD from experimental hadron properties. This framework allows us to derive a gravity dual which re…
QCD glueball sum rules and vacuum topology
Hilmar Forkel
Several key problems of QCD sum rules in the spin-0 glueball channels are resolved by implementing nonperturbative short-distance physics from direct instantons and topological cha…
Infrared degrees of freedom of Yang-Mills theory in the Schroedinger representation
Hilmar Forkel
We set up a new calculational framework for the Yang-Mills vacuum transition amplitude in the Schroedinger representation. After integrating out hard-mode contributions perturbativ…
QCD Vacuum Topology and Glueballs
Hilmar Forkel
We outline a comprehensive study of spin-0 glueball properties which, in particular, keeps track of the topological gluon structure. Specifically, we implement (semi-hard) topologi…
Topological charge screening and pseudoscalar glueballs
Hilmar Forkel
Topological charge screening in the QCD vacuum is found to provide crucial nonperturbative contributions to the short-distance expansion of the pseudoscalar (0^{-+}) glueball corre…
Direct instantons, topological charge screening and QCD glueball sum rules
Hilmar Forkel
Nonperturbative Wilson coefficients of the operator product expansion (OPE) for the spin-0 glueball correlators are derived and analyzed. A systematic treatment of the direct insta…
Resolution-dependent quark masses from meson correlators
Hilmar Forkel, Kai Schwenzer
We explore the impact of a resolution-dependent constituent quark mass, as recently applied to diffractive meson production, in QCD correlation functions of several spin-0 and spin…
New chiral-symmetry-breaking operators in pseudoscalar QCD sum rules
Hilmar Forkel
Nonperturbative Wilson coefficients associated with the leading chiral-symmetry-breaking operators in the operator product expansion of the pseudoscalar QCD correlation function ar…
Instantons and Glueballs
H. Forkel
We investigate the impact of instantons on scalar glueball properties in a largely model-independent analytical approach based on the instanton-improved operator product expansion…
Instantons and Nucleon Magnetism
Hilmar Forkel
We construct improved QCD sum rules for the nucleon magnetic moments by implementing direct-instanton contributions to the operator product expansion of the nucleon correlator in a…
A Primer on Instantons in QCD
Hilmar Forkel
These are the (twice) extended notes of a set of lectures given at the ``12th Workshop on Hadronic Interactions'' at the IF/UERJ, Rio de Janeiro (31. 5. - 2. 6. 2000). The lectures…
Bag Models with Fuzzy Boundaries
Hilmar Forkel
We discuss how hadronic bag models can be generalized in the framework of fuzzy set theory to implement effects of a smooth and extended phase boundary.