|COOKIES: By using this website you agree that we can place Google Analytics Cookies on your device for performance monitoring.|
Cohomology reveals when helicity is a diffeomorphism invariant
If you have a question about this talk, please contact Mustapha Amrani.
Topological Dynamics in the Physical and Biological Sciences
We consider the helicity of a vector field, which calculates the average linking number of the fields flowlines. Helicity is invariant under certain diffeomorphisms of its domain we seek to understand which ones.
Extending to differential (k+1)-forms on domains R, we express helicity as a cohomology class. This topological approach allows us to find a general formula for how much helicity changes when the form is pushed forward by a diffeomorphism of the domain. We classify the helicity-preserving diffeomorphisms on a given domain, finding new ones on the two-holed solid torus and proving that there are no new ones on the standard solid torus. This approach also leads us to define submanifold helicities: differential (k+1)-forms on n-dimensional subdomains of Rm.
This talk is part of the Isaac Newton Institute Seminar Series series.
This talk is included in these lists:
Note that ex-directory lists are not shown.
Other listsCU Kazakh Society Cambridge Systems Biology Centre Churchill College Phoenix Society
Other talksSyringomyelia in Cavalier King Charles Spaniels The use of recent advances in electron microscopy to study the ribosome Global bifurcation for steady gravity water waves with constant vorticity and critical layers Oncogenes and tumour suppressors (signalling and pathways) Perspectives on the surface reactivity of actinides The 2014 Pathology Congress