Takefumi Nosaka

activity

20102026

most citedCentral extensions of groups and adjoint groups of quandles

9 citations · 40 across the 33 of their papers we have counts for

collaborators

Showing 2020Show all

4 papers · 1 filter

math.GT2020

Some comparisons of Blanchfield pairings and cohomology pairings of knots

Takefumi Nosaka

We study some comparison between a bilinear cohomology pairing in local coefficients and the Blanchfield pairing of a knot. We show that the former pairing is an $S$ -equivalent inv…

math.GT2020

An $S L_{2} (R)$ -Casson invariant and Reidemeister torsions

Takefumi Nosaka

We define an $S L_{2} (R)$ -Casson invariant of closed 3-manifolds. We also observe procedures of computing the invariants in terms of Reidemeister torsions. We discuss some ap…

math.GT2020

Twisted Alexander invariants of knot group representations II; computation and duality

Takefumi Nosaka

Given a homomorphism from a link group to a group, we introduce a $K_{1}$ -class in another way, which is a generalization of the 1-variable Alexander polynomial. We compare the $K_{1}$ …

math.GT2020★ 2 cited

Twisted Alexander invariants of knot group representations

Takefumi Nosaka

Given a homomorphism from a knot group to a fixed group, we introduce an element of a $K_{1}$ -group, which is a generalization of (twisted) Alexander polynomials. We compare this $K_…

Some comparisons of Blanchfield pairings and cohomology pairings of knots

An SL2​(R)-Casson invariant and Reidemeister torsions

Twisted Alexander invariants of knot group representations II; computation and duality

Twisted Alexander invariants of knot group representations

An $S L_{2} (R)$ -Casson invariant and Reidemeister torsions