activity
20122026
most citedUpper bounds for the minimal number of singular fibers in a Lefschetz fibration over the torus

13 citations · 30 across the 7 of their papers we have counts for

collaborators

9 papers

math.GT2026

Sections, pseudosections, and multisections of Lefschetz fibrations

R. Inanc Baykur, Noriyuki Hamada

We show that not every symplectic Lefschetz fibration over the --sphere admits a smooth section, settling a long-standing open problem. To prove this, we develop a method for st…

math.GT2023

Exotic 4-manifolds with signature zero

R. Inanc Baykur, Noriyuki Hamada

We produce infinitely many distinct irreducible smooth 4-manifolds homeomorphic to #(2m+1)(CP^2 # -CP^2) and #(2n+1)(S^2 x S^2), respectively, for each m>3 and n>4. These provide t…

math.GT2020★ 2 cited

Lefschetz fibrations with arbitrary signature

R. Inanc Baykur, Noriyuki Hamada

We develop techniques to construct explicit symplectic Lefschetz fibrations over the 2-sphere with any prescribed signature and any spin type when the signature is divisible by 16.…

math.GT2020

Classification of genus- holomorphic Lefschetz pencils

Noriyuki Hamada, Kenta Hayano

In this paper, we classify relatively minimal genus- holomorphic Lefschetz pencils up to smooth isomorphism. We first show that such a pencil is isomorphic to either the pencil…

math.GT2017★ 1 cited

Simple expressions for the holed torus relations

Noriyuki Hamada

In the mapping class group of a -holed torus with , one can factorize the boundary multi-twist (or the identity when ) as the product of twelve right-hande…

math.GT2016★ 5 cited

Non-holomorphic Lefschetz fibrations with -sections

Noriyuki Hamada, Ryoma Kobayashi, Naoyuki Monden

We construct two types of non-holomorphic Lefschetz fibrations over with -sections ---hence, they are fiber sum indecomposable--- by giving the corresponding positive r…

math.GT2016★ 8 cited

Sections of the Matsumoto-Cadavid-Korkmaz Lefschetz fibration

Noriyuki Hamada

We give a maximal set of disjoint -sections of the well-known Lefschetz fibration constructed by Matsumoto, Cadavid and Korkmaz. In fact, we obtain several such sets for a fi…

math.GT2016★ 1 cited

Topology of holomorphic Lefschetz pencils on the four-torus

Noriyuki Hamada, Kenta Hayano

In this paper we discuss topological properties of holomorphic Lefschetz pencils on the four-torus. Relying on the theory of moduli spaces of polarized abelian surfaces, we first p…

math.GT2012★ 13 cited

Upper bounds for the minimal number of singular fibers in a Lefschetz fibration over the torus

Noriyuki Hamada

In this paper, we give some relations in the mapping class groups of oriented closed surfaces in the form that a product of a small number of right hand Dehn twists is equal to a s…