Signless Laplacian spectral radius and fractional matchings in graphs

Yingui Pan, Jianping Li

A fractional matching of a graph $G$ is a function $f$ giving each edge a number in $[0,1]$ such that ${\sum }_{e\in \Gamma (v)}f(e)\le 1$ for each vertex $v\in V(G)$, where $\Gamma (v)$ is the se…