No Arabic abstract
We build a bridge between two algebraic structures in SCFT: a VOA in the Schur sector of 4d $mathcal{N}=2$ theories and an associative algebra in the Higgs sector of 3d $mathcal{N}=4$. The natural setting is a 4d $mathcal{N}=2$ SCFT placed on $S^3times S^1$: by sending the radius of $S^1$ to zero, we recover the 3d $mathcal{N}=4$ theory, and the corresponding VOA on the torus degenerates to the associative algebra on the circle. We prove that: 1) the Higgs branch operators remain in the cohomology; 2) all the Schur operators of the non-Higgs type are lifted by line operators wrapped on the $S^1$; 3) no new cohomology classes are added. We show that the algebra in 3d is given by the quotient $mathcal{A}_H = {rm Zhu}_{s}(V)/N$, where ${rm Zhu}_{s}(V)$ is the non-commutative Zhu algebra of the VOA $V$ (for ${s}in{rm Aut}(V)$), and $N$ is a certain ideal. This ideal is the null space of the (${s}$-twisted) trace map $T_{s}: {rm Zhu}_{s}(V) to mathbb{C}$ determined by the torus 1-point function in the high temperature (or small complex structure) limit. It therefore equips $mathcal{A}_H$ with a non-degenerate (twisted) trace, leading to a short star-product according to the recent results of Etingof and Stryker. The map $T_{s}$ is easy to determine for unitary VOAs, but has a much subtler structure for non-unitary and non-$C_2$-cofinite VOAs of our interest. We comment on relation to the Beem-Rastelli conjecture on the Higgs branch and the associated variety. A companion paper will explore further details, examples, and some applications of these ideas.
We introduce the free quantum noncommutative fields as described by braided tensor products. The multiplication of such fields is decomposed into three operations, describing the multiplication in the algebra M of functions on noncommutative space-time, the product in the algebra H of deformed field oscillators, and the braiding by factor Psi_{M,H} between algebras M and H. For noncommutativity generated by the twist factor we shall employ the star-product realizations of the algebra M in terms of functions on standard Minkowski space. The covariance of single noncommutative quantum fields under deformed Poincare symmetries is described by the algebraic covariance conditions which are equivalent to the deformation of generalized Heisenberg equations on Poincare group manifold. We shall calculate the covariant braided field commutator, which for free quantum noncommutative fields provides the field quantization condition and is given by standard Pauli-Jordan function. For ilustration of our new scheme we present explicit calculations for the well-known case in the literature of canonically deformed free quantum fields.
We study the inner product of Bethe states in the inhomogeneous periodic XXX spin-1/2 chain of length L, which is given by the Slavnov determinant formula. We show that the inner product of an on-shell M-magnon state with a generic M-magnon state is given by the same expression as the inner product of a 2M-magnon state with a vacuum descendent. The second inner product is proportional to the partition function of the six-vertex model on a rectangular Lx2M grid, with partial domain-wall boundary conditions.
We discuss the obstruction to the construction of a multiparticle field theory on a $kappa$-Minkowski noncommutative spacetime: the existence of multilocal functions which respect the deformed symmetries of the problem. This construction is only possible for a light-like version of the commutation relations, if one requires invariance of the tensor product algebra under the coaction of the $kappa$-Poincare group. This necessitates a braided tensor product. We study the representations of this product, and prove that $kappa$-Poincare-invariant N-point functions belong to an Abelian subalgebra, and are therefore commutative. We use this construction to define the 2-point Whightman and Pauli--Jordan functions, which turn out to be identical to the undeformed ones. We finally outline how to construct a free scalar $kappa$-Poincare-invariant quantum field theory, and identify some open problems.
In this note we classify invariant star products with quantum momentum maps on symplectic manifolds by means of an equivariant characteristic class taking values in the equivariant cohomology. We establish a bijection between the equivalence classes and the formal series in the second equivariant cohomology, thereby giving a refined classification which takes into account the quantum momentum map as well.
One can derive a large class of new $mathcal{N}=1$ SCFTs by turning on $mathcal{N}=1$ preserving deformations for $mathcal{N}=2$ Argyres-Dougals theories. In this work, we use $mathcal{N}=2$ superconformal indices to get indices of $mathcal{N}=1$ SCFTs, then use these indices to derive chiral rings of $mathcal{N}=1$ SCFTs. For a large class of $mathcal{N}=2$ theories, we find that the IR theory contains only free chirals if we deform the parent $mathcal{N}=2$ theory using the Coulomb branch operator with smallest scaling dimension. Our results provide interesting lessons on studies of $mathcal{N}=1$ theories, such as $a$-maximization, accidental symmetries, chiral ring, etc.