My favorite application using eigenvalues
نویسنده
چکیده
In 2003 Vladimir Nikiforov [7] began a line of research whose aim was to build an extremal theory of graphs based on spectral theory. We will discuss some of his results and in particular we will focus on a result of Babai and Guiduli [1] that gives a Kövari-Sós-Turán type upper bound on the largest eigenvalue of the adjacency matrix of a Ks,t-free graph. This spectral approach sheds new light on these classical theorems from extremal graph theory.
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