Anomalous Transport and Generalized Axial Charge

In this paper we continue studying the modification of the axial charge in chiral media by macroscopic helicities. Recently it was shown that magnetic reconnections result in a persistent current of zero mode along flux tubes. Here we argue that in general a change in the helical part of the generalized axial charge results in the same phenomenon. Thus one may say that there is a novel realization of chiral effects requiring no initial chiral asymmetry. The transfer of flow helicity to zero modes is analyzed in a toy model based on a vortex reconnection in a chiral superfluid. Then, we discuss the balance between the two competing processes effect of reconnections and the chiral instability on the example of magnetic helicity. We argue that in the general case there is a possibility for the distribution of the axial charge between the magnetic and fermionic forms at the end of the instability.Comment: 19 pages, version accepted in PR

On consistency of hydrodynamic approximation for chiral media

We consider chiral liquids, that is liquids consisting of massless fermions and right-left asymmetric. In such media, one expects existence of electromagnetic current flowing along an external magnetic field, associated with the chiral anomaly. The current is predicted to be dissipation-free. We consider dynamics of chiral liquids, concentrating on the issues of possible instabilities and infrared sensitivity. Instabilities arise, generally speaking, already in the limit of vanishing electromagnetic constant, $\alpha_{el}\to 0$. In particular, liquids with non-vanishing chiral chemical potential might decay into right-left asymmetric states containing vortices.Comment: Published versio

Chiral Vortical Effect in Superfluid

We consider rotating superfluid pionic liquid, with superfluidity being induced by isospin chemical potential. The rotation is known to result in a chiral current flowing along the axis of the rotation. We argue that in case of superfluidity the chiral current is realized on fermionic zero modes propagating along vortices. The current evaluated in this way differs by a factor of two from the standard one. The reason is that the chiral charge is carried by zero modes which propagate with speed of light, and thus the liquid cannot be described by a single (local) velocity, like it is assumed in standard derivations.Comment: 10 pages. To be published in PRD. Minor changes added; typos fixe

Coulomb corrections to the Delbrueck scattering amplitude at low energies

In this article, we study the Coulomb corrections to the Delbrueck scattering amplitude. We consider the limit when the energy of the photon is much less than the electron mass. The calculations are carried out in the coordinate representation using the exact relativistic Green function of an electron in a Coulomb field. The resulting relative corrections are of the order of a few percent for scattering on for a large charge of the nucleus. We compare the corrections with the corresponding ones calculated through the dispersion integral of the pair production cross section and also with the magnetic loop contribution to the g-factor of a bound electron. The last one is in a good agreement with our results but the corrections calculated through the dispersion relation are not.Comment: 8 pages, 6 figure

Anomalous Zero Sound

We show that the anomalous term in the current, recently suggested by Son and Yamamoto, modifies the structure of the zero sound mode in the Fermi liquid in a magnetic field.Comment: 14 pages, 2 figure

Chiral drag force

We provide a holographic evaluation of novel contributions to the drag force acting on a heavy quark moving through strongly interacting plasma. The new contributions are chiral in that they act in opposite directions in plasmas containing an excess of left- or right-handed quarks and in that they are proportional to the coefficient of the axial anomaly. These new contributions to the drag force act either parallel to or antiparallel to an external magnetic field or to the vorticity of the fluid plasma. In all these respects, these contributions to the drag force felt by a heavy quark are analogous to the chiral magnetic effect on light quarks. However, the new contribution to the drag force is independent of the electric charge of the heavy quark and is the same for heavy quarks and antiquarks. We show that although the chiral drag force can be non-vanishing for heavy quarks that are at rest in the local fluid rest frame, it does vanish for heavy quarks that are at rest in a suitably chosen frame. In this frame, the heavy quark at rest sees counterpropagating momentum and charge currents, both proportional to the axial anomaly coefficient, but feels no drag force. This provides strong concrete evidence for the absence of dissipation in chiral transport, something that has been predicted previously via consideration of symmetries. Along the way to our principal results, we provide a general calculation of the corrections to the drag force due to the presence of gradients in the flowing fluid in the presence of a nonzero chemical potential. We close with a consequence of our result that is at least in principle observable in heavy ion collisions, namely an anticorrelation between the direction of the CME current for light quarks in a given event and the direction of the kick given to the momentum of all the heavy quarks and antiquarks in that event.Comment: 28 pages, small improvement to the discussion of gravitational anomaly, references adde

ХЛОРИДЫ ПОЛИОРГАНОСИЛОКСАНОВ С 1-МЕТИЛДИАЗОЛИЛ-МЕТИЛЕНОВЫМИ ГРУППАМИ. СИНТЕЗ И СВОЙСТВА

Chlorides of polyorganosiloxanes with 1-methyldiazolylmethylene groups were synthesized using the reaction of quaternization of poly(chloromethyl)organosiloxanes with 1-methylimidazole. The degree of completeness of this reaction was determined, and the products were characterized by the data of elemental analysis, NMR spectroscopy (1H and 29Si), TGA and DTA. The possibility in principle of obtaining statistical polyorganosiloxanes with the [1-(methyl)imidazolyl]methyl substituent in the frame of the siloxane macromolecule by quaternization of the corresponding chloromethyl-substituted organosilicon polymers with 1-methylimidazole is shown. By the method of TGA and DTA, it was found that the destruction of the obtained ionic liquids occurs when heating them in air above 265 °C. The possibility of fixing the formation of an imidazolium salt by the appearance of a chemical shift in the region ~10 ppm in the 1Н-NMR spectrum has been established.Реакцией кватернизации поли(хлорметил)органосилоксанов с 1-метилимидазолом синтезированы хлориды полиорганосилоксанов с 1-метилдиазолилметиленовыми группами. Определена степень завершенности данной реакции и продукты охарактеризованы данными элементного анализа, ЯМР-спектроскопии (1H и 29Si), ТГА и ДТА. Показана принципиальная возможность получения статистических полиорганосилоксанов с [1-(метил)-имидазолил]-метильным заместителем в обрамлении силоксановой макромолекулы реакцией кватернизации соответствующих хлорметилзамещенных кремнийорганических полимеров 1-метилимидазолом. Методом ТГА и ДТА обнаружено, что деструкция полученных ионных жидкостей наступает при нагревании на воздухе выше 265 °С. Установлена возможность фиксировать образование соли имидазолия по появлению химсдвига в области ~10 м.д. в 1Н-ЯМР-спектре