arXiv subjects

Piotr Surówka

Publications and source records attributed to Piotr Surówka.

46 records · Page 3Linked to original sources

arXiv2018

A note on symmetries in the path integral formulation of the Langevin dynamics

We study a dissipative Langevin dynamics in the path integral formulation using the Martin-Siggia-Rose formalism. The effective action is supersymmetric and we identify the supercharges. In addition we study the transformations generated by superderivatives, which were recently included in the cohomological structure emerging in the dissipative systems. We find that these transformations do not generate Ward identities, which are explicitly broken, however, they lead to universal identities, which we derive from Schwinger-Dyson equations. We confirm that the above identities hold in an explicit example of Ornstein-Uhlenbeck process.

hep-th↗

arXiv2018

Pulsating flow and boundary layers in viscous electronic hydrodynamics

Motivated by experiments on a hydrodynamic regime in electron transport, we study the effect of an oscillating electric field in such a setting. We consider a long two-dimensional channel of width $L$, whose geometrical simplicity allows an analytical study as well as hopefully permitting experimental realisation. The response depends on viscosity $ν$, driving frequency, $ω$ and ohmic heating coefficient $γ$ via the dimensionless complex variable $\frac{L^2}ν(iω+γ)=iΩ+Σ$. While at small $Ω$, we recover the static solution, a new regime appears at large $Ω$ with the emergence of a boundary layer. This includes a splitting of the location of maximal flow velocity from the centre towards the edges of the boundary layer, an an increasingly reactive nature of the response, with the phase shift of the response varying across the channel. The scaling of the total optical conductance with $L$ differs between the two regimes, while its frequency dependence resembles a Drude form throughout, even in the complete absence of ohmic heating, against which, at the same time, our results are stable. Current estimates for transport coefficients in graphene and delafossites suggest that the boundary layer regime should be experimentally accessible.

cond-mat.str-el↗

arXiv2016

A New Approach to Non-Abelian Hydrodynamics

We present a new approach to describe hydrodynamics carrying non-Abelian macroscopic degrees of freedom. Based on the Kaluza-Klein compactification of a higher-dimensional neutral dissipative fluid on a group manifold, we obtain a d=4 colored dissipative fluid coupled to Yang-Mills gauge field. We calculate the transport coefficients of the new fluid, which show the non-Abelian character of the gauge group. In particular, we obtain group-valued terms in the gradient expansions and response quantities such as the conductivity matrix and the chemical potentials. While using SU(2) for simplicity, this approach is applicable to any gauge group. Resulting a robust description of non-Abelian hydrodynamics, we discuss some links between this system and quark-gluon plasma and fluid/gravity duality.

hep-th↗

arXiv2015

Information Geometry of Hydrodynamics with Global Anomalies

We construct information geometry for hydrodynamics with global gauge and gravitational anomalies in $1+1$ and $3+1$ dimensions. We introduce the metric on a parameter space and show that turning on non-zero rotations leads to a curvature on the statistical manifold. We calculate the curvature invariant and analyze its divergences, which occur at the transition points of the system. The transition points are universal and expressed in terms of ratios of anomaly coefficients.

hep-th↗

arXiv2015

One-loop effective actions and 2D hydrodynamics with anomalies

We revisit the study of a 2D quantum field theory in the hydrodynamic regime and develop a formalism based on Euclidean one-loop partition functions that is suitable to analyze transport properties due to gauge and gravitational anomalies. To do so, we generalize the method of a modified Dirac operator developed for zero-temperature anomalies to finite temperature, chemical potentials and rotations.

hep-th↗

arXiv2014

Phenomenology of non-relativistic parity-violating hydrodynamics in 2+1 dimensions

Parity-violating fluids in two spatial dimensions can appear in a variety of contexts such as liquid crystal films, anyon fluids, and quantum Hall fluids. Nonetheless, the consequences of parity-violation on the solutions to the equations of motion are largely unexplored. In this paper, we explore phenomenological consequences of parity-violation through simple, illustrative examples. Although incompressible velocity fields are essentially unchanged by parity violation, we discuss examples where parity violation plays a role at boundaries, or in the dynamics of temperature. We then discuss new types of compressible flows which only exist in a parity-violating fluid, including new sound waves, and solitons in the dissipationless limit. We conclude with a discussion of some curious features in Rayleigh-Bénard convection of a parity-violating fluid.

cond-mat.mes-hall↗

arXiv2014

Sound-induced vortex interactions in a zero-temperature two-dimensional superfluid

We present a systematic derivation of the effective action for interacting vortices in a non-relativistic two-dimensional superfluid described by the Gross-Pitaevskii equation by integrating out longitudinal fluctuations of the order parameter. There are no logarithmically divergent coefficients in the equations of motion. Our analysis is valid in a dilute limit of vortices where the intervortex spacing is large compared to the core size, and where number fluctuations of atoms in vortex cores are suppressed. We analyze sound-induced corrections to the dynamics of a vortex-antivortex pair and show that there is no instability to annihilation, suggesting that sound-mediated interactions are not strong enough to ruin an inverse energy cascade in two-dimensional zero-temperature superfluid turbulence.

cond-mat.quant-gas↗

arXiv2014

Non-linear evolution of unintegrated gluon density at large values of coupling constant

We propose an evolution equation for unintegrated gluon densities that is valid for large values of the QCD coupling constant $\barα _s$. Our approach is based on the linear resummation model introduced by Staśto. We generalize the model including a non-linear term in the diffusive regime. The validity of the diffusive evolution at strong coupling is supported by the AdS/CFT consideration, as well as perturbative arguments. We solve the evolution equation numerically and extract the saturation scale, which we compare with the weak coupling counterpart.

hep-ph↗

arXiv2012

Anomaly/Transport in an Ideal Weyl gas

We study some of the transport processes which are specific to an ideal gas of relativistic Weyl fermions and relate the corresponding transport coefficients to various anomaly coefficients of the system. We propose that these transport processes can be thought of as arising from the continuous injection of chiral states and their subsequent adiabatic flow driven by vorticity. This in turn leads to an elegant expression relating the anomaly induced transport coefficients to the anomaly polynomial of the Ideal Weyl gas.

hep-th↗

arXiv2008

Flavors in an expanding plasma

We consider the effect of an expanding plasma on probe matter by determining time-dependent D7 embeddings in the holographic dual of an expanding viscous plasma. We calculate the chiral condensate and meson spectra including contributions of viscosity. The chiral condensate essentially confirms the expectation from the static black hole. For the meson spectra we propose a scheme that is in agreement with the adiabatic approximation. New contributions arise for the vector mesons at the order of the viscosity terms.

hep-th↗