Magnetic defects and new RG monotones
- π€ Speaker: Matthew M Roberts (University of Iceland)
- π Date & Time: Friday 31 October 2025, 10:00 - 11:00
- π Venue: Seminar Room 1, Newton Institute
Abstract
We study conformal magnetic defects corresponding to an infinitely long and thin magnetic solenoid in the context of supersymmetric quantum field theory. In four dimensions this co-dimension two defect has one new A-type trace anomaly coefficient $b$, which is monotonic under defect RG flows and depends nontrivially on the magnetic flux. We study these defects in a UV and IR fixed point of a bulk RG flow and demonstrate that $b$ is no longer monotonic, and can both increase or decrease. However, we find a particular combination of anomaly coefficients, $12a-b$, is monotonic, and conjecture that this is true for general 4d/2d defects. We also study the 3d/1d system, which has no trace anomaly, though we can still define a ``defect free energy’’, which also appears to be monotonic.
Series This talk is part of the Isaac Newton Institute Seminar Series series.
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Matthew M Roberts (University of Iceland)
Friday 31 October 2025, 10:00-11:00