Description

Combinatorics seminar

Speaker: Sudeep Stephen.

Affiliation: National University of Singapore.

Date and Time: Wednesday 09 October, 10:15 am - 11:15 am.

Venue: Ramanujan Hall, Department of Mathematics.

Title: Zero Forcing in Graphs.

Abstract: Fo a two-colouring of the vertex set of a simple graph G = (V,E), consider the following colour-change rule: a red vertex is converted to blue if it is the only red neighbour of some blue vertex. A vertex set S ⊆ V is called zero-forcing if, starting with the vertices in S blue and the vertices in the complement V \ S red, all the vertices can be converted to blue by repeatedly applying the colour-change rule. The minimum cardinality of a zero-forcing set for the graph G is called the zero-forcing number of G, denoted by Z(G). This concept was introduced by the AIM Minimum Rank –Special Graphs Work Group in [1] as a tool to bound the minimum rank of matrices associated with the graph G. In this talk, I shall give an overview of the zero forcing problem along with some of the results that we have obtained during my Ph.D candidature. To conclude, I shall state few open problems that I intend to tackle along with my mentors. References [1] AIM Minimum Rank –Special Graphs Work Group. Zero forcing sets and the minimum rank of graphs. Linear Algebra and its Applications, 428(7):16281648, 2008.

Speaker: Sudeep Stephen.

Affiliation: National University of Singapore.

Date and Time: Wednesday 09 October, 10:15 am - 11:15 am.

Venue: Ramanujan Hall, Department of Mathematics.

Title: Zero Forcing in Graphs.

Abstract: Fo a two-colouring of the vertex set of a simple graph G = (V,E), consider the following colour-change rule: a red vertex is converted to blue if it is the only red neighbour of some blue vertex. A vertex set S ⊆ V is called zero-forcing if, starting with the vertices in S blue and the vertices in the complement V \ S red, all the vertices can be converted to blue by repeatedly applying the colour-change rule. The minimum cardinality of a zero-forcing set for the graph G is called the zero-forcing number of G, denoted by Z(G). This concept was introduced by the AIM Minimum Rank –Special Graphs Work Group in [1] as a tool to bound the minimum rank of matrices associated with the graph G. In this talk, I shall give an overview of the zero forcing problem along with some of the results that we have obtained during my Ph.D candidature. To conclude, I shall state few open problems that I intend to tackle along with my mentors. References [1] AIM Minimum Rank –Special Graphs Work Group. Zero forcing sets and the minimum rank of graphs. Linear Algebra and its Applications, 428(7):16281648, 2008.

Description

Ramanujan Hall, Department of Mathematics

Date

Wed, October 9, 2019

Start Time

10:15am-11:15am IST

Duration

1 hour

Priority

5-Medium

Access

Public

Created by

DEFAULT ADMINISTRATOR

Updated

Tue, October 8, 2019 9:54pm IST