Sumio Yamada (Gakushuin University, Tokyo, Japan)
Chebyshev Laboratory Colloquium
Tuesday April 30 17:15 room 105 (14-th line V.I., 29)
In 1917, shortly after Einstein had announced his master equation on the general
relativity, H. Weyl characterized the Schwarzschild metric, which is the first
nontrivial solution to the Einstein equation, by a harmonic function. Since then,
the solutions to the Einstein equation with a certain set of symmetries are identified
with elliptic variational problems, in particular the harmonic map equation, often
called nonlinear sigma model. With Marcus Khuri and Gilbert Weinstein, we
constructed a new set of stationary solutions to the 5-dimensional vacuum Einstein
equation, which contains non-spherical event horizons, such as lens spaces. The
higher dimensional spacetime exhibit a wider range of topological structures,
compared to our 4-dimensional physical spacetime, and those stationary solutions
are thus geometrically interesting.
Everyone is welcome!