
For a finite simple graph \(G\), a strong edge colouring of \(G\) is an edge colouring in which every colour class is an induced matching. (Since each class is a matching, the colouring is proper.) The strong chromatic index of \(G\), \(\chi_{s}(G)\), is the smallest number of colours in a strong edge colouring of \(G\). The paper under review studies the strong chromatic index of random graphs \(G(n,p(n))\) where each edge arises with probability \(p(n)\) independently of all other edges. \textit{Z. Palka} [Australas. J. Comb. 18, 219-226 (1998; Zbl 0923.05042)] showed that if \(p(n)=\Theta(n^{-1})\), then \[ \lim_{n\rightarrow\infty}P\{\chi_{s}(G(n,p(n)))=O(\Delta(G(n,p(n))))\}=1 \] where, as usual, \(\Delta=\Delta(G)\) is the maximum degree of the graph. \textit{V. H. Vu} [Comb. Probab. Comput. 11, 103--111 (2002; Zbl 0991.05041)] used Rödl-nibble type arguments to show that if \(\log(n)^{1+\delta}/n\leq p(n)\leq n^{-\varepsilon}\) for any \(\varepsilon>0\) and \(\deltan^{-\varepsilon}\) for all \(\varepsilon>0\). The main result is that \[ \lim_{n\rightarrow\infty}P\{\frac{(1-o(1))p{n\choose 2}}{\log_{1/(1-p)}(n)}\leq \chi_{s}(G(n,p(n)))\leq \frac{(2+o(1))p{n\choose 2}}{\log_{1/(1-p)}(n)}\}=1. \] The lower bound is easy: a typical \(G(n,p)\) has about \(p{n\choose 2}\) edges and it is easy to see, using the first moment method, that the largest induced matching in \(G(n,p)\) has about \(\log_{1/(1-p)}(n)\) edges. More interesting part is the upper bound, derived from the result of \textit{B. Bollobás} [Combinatorica 8, 49--56 (1988; Zbl 0666.05033)] to the effect that the (ordinary) vertex chromatic number \(\chi(G(n,p))\) for \(0
Strong chromatic index, Coloring of graphs and hypergraphs, Random graphs (graph-theoretic aspects), Discrete Mathematics and Combinatorics, strong chromatic index, random graphs, Random graphs, Theoretical Computer Science
Strong chromatic index, Coloring of graphs and hypergraphs, Random graphs (graph-theoretic aspects), Discrete Mathematics and Combinatorics, strong chromatic index, random graphs, Random graphs, Theoretical Computer Science
| selected citations These citations are derived from selected sources. This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | 5 | |
| popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network. | Average | |
| influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | Top 10% | |
| impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Average |
