De Witt Sumners
Title: Reconnection in Biology and Physics
Date: Friday, November 15, 2019
Place and Time: Room 101, Love Building, 3:35-4:25 pm
Refreshments: Room 204, Love Building, 3:00 pm
Reconnection is a fundamental event in many areas of science, including the interaction of vortices
in classical and quantum fluids, magnetic flux tubes in magnetohydrodynamics and plasma physics, and site-specific
recombination in DNA. The helicity of a collection of flux tubes can be calculated in terms of writhe, twist and
linking among tubes. We prove that the writhe helicity is conserved under anti-parallel reconnection . We
will discuss the mathematical similarities between reconnection events in
biology and physics, and the relationship between iterated reconnection and
curve topology. We will discuss helicity and reconnection in a tangle of
confined vortex circles in a superfluid.
 Laing C.E., Ricca R.L. & Sumners D.W. (2015) Conservation of writhe helicity under anti-parallel reconnection, Nature Scientific Reports 5:9224/ DOI: 10.1038/srep09224.