Valentina Bais

activity

20242026

collaborators

9 papers

math.GT2026

Cobordism groups of dihedral branched covers

Valentina Bais, Alexandra Kjuchukova

For every integer $n \geq 1$ , we compute the cobordism groups of dihedral $n$ -fold branched covers of $S^{3}$ with oriented and non-oriented branching sets. We show that the groups a…

math.GT2026

Branched coverings of simply connected $4$ -manifolds

Valentina Bais, Riccardo Piergallini, Daniele Zuddas

We show that, given $d \geq 4$ and two closed connected oriented PL $4$ -manifolds $M$ and $N$ such that $N$ has a handle decomposition with no $1$ - and $3$ -handles, there exists a…

math.GT2026

Branched covering representation of non-orientable $4$ -manifolds

Valentina Bais, Riccardo Piergallini, Daniele Zuddas

We show that every closed connected non-orientable PL $4$ -manifold $X$ is a simple branched covering of $\RP^4$. We also show that $X$ is a simple branched covering of the twisted…

math.GT2026

A cut-and-paste mechanism to introduce fundamental group and construct new four-manifolds

Valentina Bais, Rafael Torres

We introduce a simple cut-and-paste mechanism to construct both orientable and nonorientable four-manifolds from a given initial one. This mechanism alters the fundamental group wh…

math.GT2025

On the detection of knotted spheres by their traces in high dimensions

Valentina Bais, Alessio Di Prisa, Daniel Hartman +8

For every $n \geq 4$ , we demonstrate the existence of non-isotopic smooth $(n - 2)$ -knots in $S^{n}$ with diffeomorphic traces by generalising the RBG link construction to all dimensio…

math.GT2025

Smooth structures on non-orientable $4$ -manifolds via twisting operations

Valentina Bais, Rafael Torres

Four observations compose the main results of this note. The first records the existence of a smoothly embedded 2-sphere $S$ inside $R P^{2} \times S^{2}$ such that performing…

Cobordism groups of dihedral branched covers

Branched coverings of simply connected 4-manifolds

Branched covering representation of non-orientable 4-manifolds

A cut-and-paste mechanism to introduce fundamental group and construct new four-manifolds

On the detection of knotted spheres by their traces in high dimensions

Smooth structures on non-orientable 4-manifolds via twisting operations

Branched coverings of simply connected $4$ -manifolds

Branched covering representation of non-orientable $4$ -manifolds

Smooth structures on non-orientable $4$ -manifolds via twisting operations