Sino-Russian Student Mathematical Seminar November 21, 2025 10:30–11:30, Moscow time zone; Moscow, Steklov Mathematical Institute of RAS, Room 104 (Gubkina, 8); Novosibirsk, Sobolev Institute of Mathematics of SB RAS, mini conference hall (in the additional building on Koptyug avenue, 4/1)
Abstract:
It is well-known that the Alexander polynomial of a fibered knot must be
monic. But in general the converse is not true. In this talk, we
introduce the universal $L^2$-torsion of a 3-manifold, an invariant
defined in analogy with the classical torsion, but using tools from
$L^2$-theory. We will show that this invariant detects fibered
3-manifolds. Moreover, we extend the definition of the universal
$L^2$-torsion to taut sutured 3-manifolds and show that it
detects product sutured manifolds.
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