BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Nabil Iqbal (Durham University) DTSTART:20200807T160000Z DTEND:20200807T173000Z DTSTAMP:20260423T005650Z UID:CMU-TP/5 DESCRIPTION:Title: F rom generalized global symmetries to pulsar magnetospheres\nby Nabil I qbal (Durham University) as part of Carnegie Mellon theoretical physics\n\ n\nAbstract\nCertain quantum field theories possess generalized global sym metries\; just as ordinary global symmetries enforce the conversation of p article number\, generalized global symmetries enforce the conservation of extended objects\, such as strings. I will review this symmetry principle and argue that it governs the long-distance physics of conventional 4d el ectromagnetism\, where the strings in question are magnetic field lines. I will then apply it to construct a novel effective theory for the descript ion of strongly magnetized plasmas. One potential application of this new effective theory is to astrophysical pulsars\, which are thought to be sur rounded by strong magnetic fields as well as a high density of charged par ticles\; the resulting zero temperature system is highly nonlinear. At lea ding order in derivatives our new effective theory agrees with the standar d treatment in terms of ``force-free electrodynamics''. The inclusion of h igher derivative terms however generically results in new and potentially observationally relevant effects\, such as electric fields that accelerate charges to high energies along magnetic field lines.\n LOCATION:https://researchseminars.org/talk/CMU-TP/5/ END:VEVENT END:VCALENDAR