2.00 pm, Lecture Hall 2 Graph homomorphisms from a topological point of view Shuchita Goyal IIT Bombay. 25-07-18 Abstract Finding the chromatic number of a graph has always been an interesting problem in Graph Theory. In this talk, we will see how a graph $G$ gives rise to a topological space which contains crucial information about the chromatic number of $G$. In particular, we will see how Lovasz proved that the chromatic number of the Kneser graph, $KG_{n,k}$, is $ n-2k+2$ using topological tools. For a graph $G$, we will also explore the topology of the space of $H$-colourings of $G$ and its relations with the chromatic number of $G$ and $H$.
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