(2) Graph Connectivity Recall that the eigenvalues of the Laplacian of a graph on
n
vertices can be ordered as
0=\lambda _(1)<=\lambda _(2)<=cdots<=\lambda _(n)
. Consider the following graph
H
: (a) Write down the Laplacian
L_(H)
of the graph
H
. (b) Compute the quadratic function
x^(TT)L_(H)x
and write it as a sum of squares. (c) Find a basis for the eigenspace of
L_(H)
corresponding to the eigenvalue 0 . (d) Based on the above which is the first eigenvalue of
L_(H)
that is going to be positive? (e) What is the relationship between the arithmetic multiplicity of the eigenvalue 0 and the number of connected components in a graph? Explain.