6 citations · 7 across the 8 of their papers we have counts for
9 papers
Hopf monoids in perturbative algebraic quantum field theory
William Norledge
We develop an algebraic formalism for perturbative quantum field theory (pQFT) which is based on Joyal's combinatorial species. We show that certain basic structures of pQFT are co…
Braid arrangement bimonoids and the toric variety of the permutohedron
William Norledge
We show that the toric variety of the permutohedron (=permutohedral space) has the structure of a cocommutative bimonoid in species, with multiplication/comultiplication given by e…
Species-theoretic foundations of perturbative quantum field theory
William Norledge
We develop an algebraic formalism for perturbative quantum field theory (pQFT) which is based on Joyal's combinatorial species. We show that certain basic structures of pQFT are co…
Hopf monoids, permutohedral cones, and generalized retarded functions
William Norledge, Adrian Ocneanu
The commutative Hopf monoid of set compositions is a fundamental Hopf monoid internal to vector species, having undecorated bosonic Fock space the combinatorial Hopf algebra of qua…
The adjoint braid arrangement as a combinatorial Lie algebra via the Steinmann relations
Zhengwei Liu, William Norledge, Adrian Ocneanu
We study a certain discrete differentiation of piecewise-constant functions on the adjoint of the braid hyperplane arrangement, defined by taking finite-differences across hyperpla…
Singer cyclic lattices of type M
William Norledge
We construct the type-preserving panel-regular lattices in buildings of type M, for M with entries two, three or infinity, which have cyclic stabilizers of spherical 2-residues. We…
Quotients of buildings by groups acting freely on chambers
William Norledge
We introduce certain directed multigraphs with extra structure, called Weyl graphs, which model quotients of Tits buildings by type-preserving chamber-free group actions. Their adv…
Stacky Buildings
William Norledge
We introduce structures which model quotients of buildings by type-preserving group actions. These structures, which we call W-groupoids for W a Coxeter group, generalize Bruhat de…
Maximal torsion-free subgroups of certain lattices of hyperbolic buildings and Davis complexes
William Norledge, Anne Thomas, Alina Vdovina
We give an explicit construction of a maximal torsion-free finite-index subgroup of a certain type of Coxeter group. The subgroup is constructed as the fundamental group of a finit…