arXiv subjects

Mykhailo Hontarenko

Publications and source records attributed to Mykhailo Hontarenko.

7 recordsLinked to original sources

arXiv2026

Absolutely Maximally Entangled States of $2q$ Parties in Every Odd Prime-Power Dimension $q$

Absolutely maximally entangled (AME) states represent an extreme form of multipartite entanglement: every reduced system containing at most half of the parties is maximally mixed. These states provide perfect tensors and optimal quantum error-correcting codes, yet their existence is known only in restricted parameter regimes. For every odd prime power $q=p^e\ge3$, we construct a stabilizer $\mathrm{AME}(2q,q)$ state whose normalized one-party projection yields a stabilizer $\mathrm{AME}(2q-1,q)$ state. A closed-form $q\times q$ bordered-circulant matrix $A_q$ over $\mathbb{F}_{q^2}$ generates a Hermitian self-dual maximum distance separable (MDS) code $[2q,q,q+1]_{q^2}$, which lies outside the extended Reed-Solomon classes. In suitable bases, the amplitude tensors define normalized $q$-unitary complex Hadamard matrices of order $q^q$ with $p$th-root phases. Additional constructions yield $\mathrm{AME}(q+3,q)$ states and families at intermediate particle numbers through explicit rescalings of selected submatrices. We also provide nine explicit parent matrices and the corresponding one-party projections.

quant-ph↗

arXiv2026

Quantum Airy Structures and Matrix Models: a supercurrent approach

We develop a super-current formulation of $\mathcal{N}=1$ super-Virasoro constraints for external-source models. By assigning bosonic and fermionic monodromies independently, we unify the NS-NS, NS-R, R-NS, and R-R sectors. For each, a super-Miwa transformation represents the projected super energy-momentum tensor as a differential operator in spectral variables. Dilaton shifts yield Super Quantum Airy Structures in the NS-NS and R-NS sectors, whereas the R-R and NS-R sectors require an additional odd coordinate. Our principal result is an exact similarity transformation relating the NS-NS and R-R differential constraints. The intertwining prefactor combines a bosonic determinant, a cubic Airy weight, and a Grassmann exponential kernel defined by the difference of Neveu--Schwarz and Ramond fermionic propagators. These results establish a concrete candidate system of Ward identities for a supersymmetric extension of the Kontsevich model, delineating the precise algebraic and analytic properties of the measure and fermionic kernel required for its potential matrix-model realization.

hep-th↗

arXiv2025

A $k$-contact Geometrical Approach to Pseudo-Gauge Transformation

We propose a starting point to the geometric description for the pseudo-gauge ambiguity in relativistic hydrodynamics, showing that it corresponds to the freedom to redefine the thermodynamic equilibrium state of the system. To do this, we develop for the first time a description of a relativistic hydrodynamic-like theory using $k$-contact geometry. In this approach, thermodynamic laws are encoded in a $k$-contact form, thermodynamical states are described via $k$-contact Legendrian submanifolds, and conservation laws emerge as a consequence of Hamilton-de Donder-Weyl (HdDW) equations. The inherent non-uniqueness of these solutions is identified as the source of the pseudo-gauge freedom. We explicitly demonstrate how this redefinition of equilibrium works in a model of a Bjorken-like expansion, where a pseudo-gauge transformation is shown to leave the physical dissipation invariant.

math-ph↗

arXiv2025

Dynamical constraints on pseudo-gauge transformations

Classical pseudo-gauge transformations are discussed in the context of hydrodynamic models of heavy-ion collisions. A decomposition of the pseudo-gauge transformation into Lorentz-invariant tensors is made, which allows for better interpretation of its physical consequences. For pseudo-gauge transformations connecting two symmetric energy-momentum tensors, we find that the super-potential $Φ^{λμν}$ must obey a conservation law of the form $\partial_λΦ^{λμν} = 0$. This equation, referred to below as the STS condition, represents a constraint that is hardly possible to be satisfied for tensors constructed out of the basic hydrodynamic variables such as temperature, baryon chemical potential, and the hydrodynamic flow. However, in a special case of the boost-invariant flow, the STS condition is automatically fulfilled and a non-trivial residual pseudo-gauge transformation defined by a single scalar field is allowed. In this case the bulk and shear viscosity coefficients become pseudo-gauge dependent; however, their specific linear combination appearing in the equations of motion remains pseudo-gauge invariant. This finding provides new insights into the role of pseudo-gauge transformations and pseudo-gauge invariance.

hep-ph↗

arXiv2024

Hybrid approach to perfect and dissipative spin hydrodynamics

A hybrid framework of spin hydrodynamics is proposed that combines the results of kinetic theory for particles with spin 1/2 with the Israel-Stewart method of introducing nonequilibrium dynamics. The framework of kinetic theory is used to define the perfect-fluid description that conserves baryon number, energy, linear momentum and spin part of angular momentum. This leads to the entropy conservation although, in the presence of spin degrees of freedom, the perfect-fluid formalism includes extra terms whose structure is usually attributed to dissipation. The genuine dissipative terms appear from the condition of positive entropy production in nonequilibrium processes. They are responsible for the transfer between the spin and orbital parts of angular momentum, with the total angular momentum being conserved.

hep-ph↗

arXiv2024

Bulk-boundary correspondence from hyper-invariant tensor networks

We introduce a tensor network designed to faithfully simulate the AdS/CFT correspondence, akin to the multi-scale entanglement renormalization ansatz (MERA), following hyper-invariant tensor network. The proposed construction integrates bulk indices within the network architecture to uphold the key features of the HaPPY code, including complementary recovery. This framework accurately reproduces the boundary conformal field theory's (CFT) two- and three-point correlation functions, while considering the image of any bulk operator. Furthermore, we provide an explicit methodology for calculating the correlation functions in an efficient manner. Our findings highlight the physical aspects of the relation between bulk and boundary within the tensor network models, contributing to the understanding and simulation of holographic principles in quantum information.

quant-ph↗

arXiv2024

Generalized thermodynamic relations for perfect spin hydrodynamics

Generalized thermodynamic relations are introduced into the framework of a relativistic perfect spin hydrodynamics. They allow for consistent treatment of spin degrees of freedom, including the use of spin tensors whose structure follows from microscopic calculations. The obtained results are important for establishing consistency between different formulations of spin hydrodynamics and form the basis for introducing dissipative corrections.

hep-ph↗