196 citations · 2.6k across the 56 of their papers we have counts for
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Critical O(N) models above four dimensions: Small-N solutions and stability
Astrid Eichhorn, Lukas Janssen, Michael M. Scherer
We explore O(N) models in dimensions . Specifically, we investigate models of an O(N) vector field coupled to an additional scalar field via a cubic interaction. Recent resu…
Spontaneous breaking of Lorentz symmetry in -dimensional QED
Lukas Janssen
The phase diagram of massless quantum electrodynamics in three space-time dimensions as a function of fermion flavor number exhibits two well-known phases: at large $N > N_c^{c…
Critical and theories near six dimensions
Igor F. Herbut, Lukas Janssen
We consider -symmetric bosonic field theories above four dimensions, and propose a new reformulation in terms of an irreducible tensorial field with a cubic and Yukawa…
Fixed-point structure of low-dimensional relativistic fermion field theories: Universality classes and emergent symmetry
Friedrich Gehring, Holger Gies, Lukas Janssen
We investigate a class of relativistic fermion theories in 2<d<4 space-time dimensions with continuous chiral U(Nf)xU(Nf) symmetry. This includes a number of well-studied models, e…
Critical behavior of the (2+1)-dimensional Thirring model
Lukas Janssen, Holger Gies
We investigate chiral symmetry breaking in the (2+1)-dimensional Thirring model as a function of the coupling as well as the Dirac flavor number Nf with the aid of the functional r…
UV fixed-point structure of the three-dimensional Thirring model
Holger Gies, Lukas Janssen
We investigate the UV fixed-point structure of the three-dimensional Thirring model by means of the functional renormalization group (RG). We classify all possible 4-fermi interact…
Phase transition and critical behavior of d=3 chiral fermion models with left/right asymmetry
Holger Gies, Lukas Janssen, Stefan Rechenberger +1
We investigate the critical behavior of three-dimensional relativistic fermion models with a U(N_L)_L x U(1)_R chiral symmetry reminiscent of the Higgs-Yukawa sector of the standar…
Instanton constituents and fermionic zero modes in twisted CP(n) models
Wieland Brendel, Falk Bruckmann, Lukas Janssen +2
We construct twisted instanton solutions of CP(n) models. Generically a charge-k instanton splits into k(n+1) well-separated and almost static constituents carrying fractional topo…