BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Danny Brattan (University of Genova) DTSTART:20200908T140000Z DTEND:20200908T150000Z DTSTAMP:20260423T023047Z UID:HoloTube/18 DESCRIPTION:Title: Diffusion in a magnetic field\nby Danny Brattan (University of Genov a) as part of HoloTube: Applied holography webinars\n\n\nAbstract\nEven wi th the simplifying assumption of non-dynamical (external) electromagnetic fields\, magnetohydrodynamics is a technically subtle framework for unders tanding the long wavelength and low frequency regime of interacting theori es. One of these technicalities is that for many models of interdisciplina ry relevance the magnetic field is a constant in equilibrium. Intuitively however\, for momentum to be approximately conserved and enter the hydrody namic description\, the magnetic field must vanish at leading order.\n\nIn this talk I will review recent work that sheds light on some of the uniqu e features of magnetohydrodynamics in (2+1)-dimensions\, with a particular emphasis on diffusion. I will show that there is a qualitative and quanti tative improvement in matching holographic and hydrodynamic correlators if one correctly accounts for the magnetic field being non-zero in the backg round. Consequently\, I will give conclusive evidence that there is a non- zero incoherent Hall conductivity in the absence of parity violation that was missed in previous approaches. Finally\, I will discuss some ways in w hich this new approach can be applied to non-stringy systems.\n LOCATION:https://researchseminars.org/talk/HoloTube/18/ END:VEVENT END:VCALENDAR