Tensor Field Theory Research Articles

Lorentz-violating gaugeon formalism for rank-2 tensor theory

We develop a BRST symmetric gaugeon formalism for the Abelian rank-2 antisymmetric tensor field in the Lorentz-breaking framework. The Lorentz-breaking is achieved here by considering a proper subgroup of Lorentz group together with translation. In this scenario, the gaugeon fields together with the standard fields of the Abelian rank-2 antisymmetric tensor theory get mass. In order to develop the gaugeon formulation for this theory in very special relativity (VSR), we first introduce a set of dipole vector fields as a quantum gauge freedom to the action. In order to quantize the dipole vector fields, the VSR-modified gauge-fixing and corresponding ghost action are constructed as the classical action is invariant under a VSR-modified gauge transformation. Further, we present a Type I gaugeon formalism for the Abelian rank-2 antisymmetric tensor field theory in VSR. The gauge structures of Fock space constructed with the help of BRST charges are also discussed.

Examples of symmetry-preserving truncations in tensor field theory

We consider the tensor formulation of the nonlinear O(2) sigma model and its gauged version (the compact Abelian Higgs model), on a $D$-dimensional cubic lattice, and show that tensorial truncations are compatible with the general identities derived from the symmetries of these models. This means that the universal properties of these models can be reproduced with highly simplified formulations desirable for implementations with quantum computers or for quantum simulations experiments. We discuss the extensions to global non-Abelian symmetries, discrete symmetries and pure gauge Abelian models.

On the large N limit of Schwinger-Dyson equations of a rank-3 tensor field theory

We analyze in this paper the large N limit of the Schwinger-Dyson equations in a rank-3 tensor quantum field theory, which are derived with the help of Ward-Takahashi identities. In order to have a well-defined large N limit, appropriate scalings in powers of N for the various terms present in the action are explicitly found. A perturbative check of our results is done up to second order in the coupling constant.

Constructive Tensor Field Theory: The $${T_{4}^{4}}$$ T 4 4 Model

We continue our constructive study of tensor field theory through the next natural model, namely the rank four tensor theory with quartic melonic interactions and propagator inverse of the Laplacian on $U(1)^4$. This superrenormalizable tensor field theory has a power counting quite similar to ordinary $\phi^4_3$. We control the model via a multiscale loop vertex expansion which has to be pushed quite beyond the one of the $T^4_3$ model and we establish its Borel summability in the coupling constant. This paper is also a step to prepare the constructive treatment of just renormalizable models, such as the $T^4_5$ model with quartic melonic interactions.

Exact relation between canonical and metric energy-momentum tensors for higher derivative tensor field theories

We discuss the relation between canonical and metric energy-momentum tensors for field theories with actions that can depend on the higher derivatives of tensor fields in a flat spacetime. In order to obtain it we use a modification of the Noether's procedure for curved space-time. For considered case the difference between these two tensors turns out to have more general form than for theories with no more than first order derivatives. Despite this fact we prove that the difference between corresponding integrals of motion still has the form of integral over 2-dimensional surface that is infinitely remote in the spacelike directions.

Renormalizable enhanced tensor field theory: The quartic melonic case

Tensor field theory is the quantum field theoretic counterpart of tensor models and enhanced tensor field theory enlarges this theory space to accommodate “enhanced tensor interactions.” These interactions were introduced to explore new large N limits and to probe different phases for tensor models. We undertake the multi-scale renormalization analysis for two types of enhanced theories with rank d tensor fields ϕ:(U(1)D)d→C and with the so-called quartic “melonic” interactions of the form p2aϕ4 reminiscent of derivative couplings expressed in momentum space. Scrutinizing the degree of divergence of both theories, we identify generic conditions for their renormalizability at all orders of perturbation at high momenta, i.e., the ultraviolet regime. For the first type of theory, we identify a 2-parameter space of just-renormalizable models for generic (d, D). These models have dominant non-melonic four-point functions. Finally, by specifying the parameters, we detail the renormalization analysis of the second type of model which is more exotic: it exhibits an infinite family of logarithmically divergent two-point amplitudes and all four-point amplitudes are convergent.

Edge state quantization: vector fields in Rindler

We present a detailed discussion of the entanglement structure of vector fields through canonical quantization. We quantize Maxwell theory in Rindler space in Lorenz gauge, discuss the Hilbert space structure and analyze the Unruh effect. As a warm-up, in 1 + 1 dimensions, we compute the spectrum and prove that the theory is thermodynamically trivial. In d + 1 dimensions, we identify the edge sector as eigenstates of horizon electric flux or equivalently as states representing large gauge transformations, localized on the horizon. The edge Hilbert space is generated by inserting a generic combination of Wilson line punctures in the edge vacuum, and the edge states are identified as Maxwell microstates of the black hole. This construction is repeated for Proca theory. Extensions to tensor field theories, and the link with Chern-Simons are discussed.

2PI effective action for the SYK model and tensor field theories

We discuss the two-particle irreducible (2PI) effective action for the SYK model and for tensor field theories. For the SYK model the 2PI effective action reproduces the bilocal reformulation of the model without using replicas.In general tensor field theories the 2PI formalism is the only way to obtain a bilocal reformulation of the theory, and as such is a precious instrument for the identification of soft modes and for possible holographic interpretations. We compute the 2PI action for several models, and push it up to fourth order in the 1/N expansion for the model proposed by Witten in [1], uncovering a one-loop structure in terms of an auxiliary bilocal action.

Interacting Non-Abelian Anti-Symmetric Tensor Field Theories

Non-Abelian Anti-symmetric Tensor fields interacting with vector fields have a complicated constraint structure. We enlarge the gauge invariance in this system. Relevant gauge invariant quantities including the Hamiltonian are obtained. We also make introductory remarks on a different but more complicated gauge theory.

Remarks on a B ∧ F model with topological mass from gauging spin

Aspects of screening and confinement are reassessed for a model with topological mass with the gauging of spin. Our discussion is carried out using the gauge-invariant, but path-dependent, variables formalism. We explicitly show that the static potential profile is the sum of a Yukawa and a linear potential, leading to the confinement of static external charges. Interestingly enough, similar results are obtained in a theory of antisymmetric tensor fields that results from the condensation of topological defects as a consequence of the Julia-Toulouse mechanism.

Quantum Self-Frictional Relativistic Nucleoseed Spinor-Type Tensor Field Theory of Nature

For study of quantum self-frictional (SF) relativistic nucleoseed spinor-type tensor (NSST) field theory of nature (SF-NSST atomic-molecular-nuclear and cosmic-universe systems) we use the complete orthogonal basis sets of22s+1-component column-matrices type SFΨnljmjδ⁎s-relativistic NSST orbitals (Ψδ⁎s-RNSSTO) and SFXnljmjs-relativistic Slater NSST orbitals (Xs-RSNSSTO) through theψnlmlδ⁎-nonrelativistic scalar orbitals (ψδ⁎-NSO) andχnlml-nonrelativistic Slater type orbitals (χ-NSTO), respectively. Hereδ⁎=pl⁎orδ⁎=α⁎andpl⁎=2l+2-α⁎, α⁎are the integer(α⁎=α, -∞<α≤2) or noninteger(α⁎≠α, -∞<α⁎<3) SF quantum numbers, wheres=0,1/2,1,3/2,2,…. We notice that the nonrelativisticψδ⁎-NSO andχ-NSTO orbitals themselves are obtained from the relativisticΨδ⁎s-RNSSTO andXs-RSNSSTO functions fors=0, respectively. The column-matrices-type SFY1jmjls-RNSST harmonics (Y1ls-RNSSTH) andY2jmjls-modified NSSTH (Y2ls-MNSSTH) functions for arbitrary spinsintroduced by the author in the previous papers are also used. The one- and two-center one-range addition theorems forψδ⁎-NSO and nonintegern χ-NSTO orbitals are presented. The quantum SF relativistic nonperturbative theory forVnljmjδ⁎-RNSST potentials (Vδ⁎-RNSSTP) and their derivatives is also suggested. To study the transportations of mass and momentum in nature the quantum SF relativistic NSST gravitational photon (gph) withs=1is introduced.

Renormalization of a tensorial field theory on the homogeneous space SU(2)/U(1)

We study the renormalization of a general field theory on the homogeneous space (SU(2)/ with tensorial interaction and gauge invariance under the diagonal action of SU(2). We derive the power counting for arbitrary d. For the case d = 4, we prove perturbative renormalizability to all orders via multi-scale analysis, study both the renormalized and effective perturbation series, and establish the asymptotic freedom of the model. We also outline a general power counting for the homogeneous space , of direct interest for quantum gravity models in arbitrary dimension, and point out the obstructions to the direct generalization of our results to these cases.

Basis tensor gauge theory: Reformulating gauge theories with basis tensor fields

We reformulate gauge theories in analogy with the vierbein formalism of general relativity. More specifically, we reformulate gauge theories such that their gauge dynamical degrees of freedom are local fields that transform linearly under the dual representation of the charged matter field. These local fields, which naively have the interpretation of non-local operators similar to Wilson lines, satisfy constraint equations. A set of basis tensor fields are used to solve these constraint equations, and their field theory is constructed. A new local symmetry in terms of the basis tensor fields is used to make this field theory local and maintain a Hamiltonian that is bounded from below. The field theory of the basis tensor fields is what we call the basis tensor gauge theory.

Polchinski’s exact renormalisation group for tensorial theories: Gaußian universality and power counting

In this paper, we use the exact renormalisation in the context of tensor models and group field theories. As a byproduct, we rederive Gaußian universality for random tensors and provide a general power counting for Abelian tensorial field theories with a closure constraint, leading us to a only five renormalisable theories.

Random Tensors and Quantum Gravity

We provide an informal introduction to tensor field theories and to their associated renormalization group. We focus more on the general motivations coming from quantum gravity than on the technical details. In particular we discuss how asymptotic freedom of such tensor field theories gives a concrete example of a natural "quantum relativity" postulate: physics in the deep ultraviolet regime becomes asymptotically more and more independent of any particular choice of Hilbert basis in the space of states of the universe.

Constructive Tensor Field Theory: the $${T^4_3}$$ T 3 4 Model

We build constructively the simplest tensor field theory which requires some renormalization, namely the rank three tensor theory with quartic interactions and propagator inverse of the Laplacian on $U(1)^3$. This superrenormalizable tensor field theory has a power counting almost similar to ordinary $\phi^4_2$. Our construction uses the multiscale loop vertex expansion (MLVE) recently introduced in the context of an analogous vector model. However to prove analyticity and Borel summability of this model requires new estimates on the intermediate field integration, which is now of matrix rather than of scalar type.

Reducible gauge theories in very special relativity

In this paper we analyze the tensor field (reducible gauge) theories in the context of very special relativity (VSR). Particularly, we study the VSR gauge symmetry as well as VSR BRST symmetry of Kalb-Ramond and Abelian 3-form fields involving a fixed null vector. We observe that the Kalb-Ramond and Abelian 3-form fields and corresponding ghosts get masses in VSR framework. The effective action in VSR-type axial gauge is greatly simplified compared with the VSR-type Lorenz gauge. Further, we quantize these models using a Batalin-Vilkovisy (BV) formulation in VSR.

Renormalization and Hopf algebraic structure of the five-dimensional quartic tensor field theory

This paper is devoted to the study of renormalization of the quartic melonic tensor model in dimension (=rank) five. We review the perturbative renormalization and the computation of the one loop beta function, confirming the asymptotic freedom of the model. We then define the Connes–Kreimer-like Hopf algebra describing the combinatorics of the renormalization of this model and we analyze in detail, at one- and two-loop levels, the Hochschild cohomology allowing to write the combinatorial Dyson–Schwinger equations. Feynman tensor graph Hopf subalgebras are also exhibited.

Why are tensor field theories asymptotically free?

In this pedagogic letter we explain the combinatorics underlying the generic asymptotic freedom of tensor field theories. We focus on simple combinatorial models with a propagator and quartic interactions and on the comparison between the intermediate field representations of the vector, matrix and tensor cases. The transition from asymptotic freedom (tensor case) to asymptotic safety (matrix case) is related to the crossing symmetry of the matrix vertex, whereas in the vector case, the lack of asymptotic freedom (“Landau ghost”), as in the ordinary scalar case, is simply due to the absence of any wave function renormalization at one loop.

Cosmological evolution in a two-brane warped geometry model

We study an effective 4-dimensional scalar–tensor field theory, originated from an underlying brane–bulk warped geometry, to explore the scenario of inflation. It is shown that the inflaton potential naturally emerges from the radion energy–momentum tensor which in turn results in an inflationary model of the Universe on the visible brane that is consistent with the recent results from the Planck's experiment. The dynamics of modulus stabilization from the inflaton rolling condition is demonstrated. The implications of our results in the context of recent BICEP2 results are also discussed.