An Improved Upper Bound on the Density of Universal Random Graphs

We give a polynomial time randomized algorithm that, on receiving as input a pair (H,G) of n-vertex graphs, searches for an embedding of H into G. If H has bounded maximum degree and G is suitably dense and pseudorandom, then the algorithm succeeds with high probability. Our algorithm proves that, for every integer d≥3 and suitable constant C=Cd, as n→∞, asymptotically almost all graphs with n vertices and ⌊Cn2-1/d log1/dn⌋ edges contain as subgraphs all graphs with n vertices and maximum degree at most d.

[1]  E. Chong,et al.  Wiley‐Interscience Series in Discrete Mathematics and Optimization , 2011 .

[2]  Domingos Dellamonica,et al.  Universality of random graphs , 2008, SODA '08.

[3]  Alan M. Frieze,et al.  Random graphs , 2006, SODA '06.

[4]  Yoshiharu Kohayakawa,et al.  Universality and tolerance , 2000, Proceedings 41st Annual Symposium on Foundations of Computer Science.

[5]  Alan M. Frieze,et al.  Almost universal graphs , 2006, Random Struct. Algorithms.

[6]  Endre Szemerédi,et al.  A fast algorithm for equitable coloring , 2010, Comb..

[7]  Yoshiharu Kohayakawa,et al.  Near-optimum Universal Graphs for Graphs with Bounded Degrees , 2001, RANDOM-APPROX.

[8]  Arnold L. Rosenberg,et al.  Universal Graphs for Bounded-Degree Trees and Planar Graphs , 1989, SIAM J. Discret. Math..

[9]  Noga Alon,et al.  Optimal universal graphs with deterministic embedding , 2008, SODA '08.

[10]  Michael R. Capalbo,et al.  Sparse universal graphs for bounded-degree graphs , 2007 .

[11]  Michael R. Capalbo,et al.  Small universal graphs , 1999, STOC '99.

[12]  Domingos Dellamonica,et al.  An algorithmic Friedman--Pippenger theorem on tree embeddings and applications to routing , 2006, SODA '06.

[13]  S. Ross A random graph , 1981 .

[14]  M. Habib Probabilistic methods for algorithmic discrete mathematics , 1998 .

[15]  Wojciech Samotij,et al.  Large Bounded Degree Trees in Expanding Graphs , 2010, Electron. J. Comb..

[16]  Alexandr V. Kostochka,et al.  A Short Proof of the Hajnal–Szemerédi Theorem on Equitable Colouring , 2008, Combinatorics, Probability and Computing.

[17]  Svante Janson,et al.  Poisson Approximation for Large Deviations , 1990, Random Struct. Algorithms.

[18]  P. Lax Proof of a conjecture of P. Erdös on the derivative of a polynomial , 1944 .

[19]  W. T. Gowers,et al.  RANDOM GRAPHS (Wiley Interscience Series in Discrete Mathematics and Optimization) , 2001 .

[20]  Svante Janson,et al.  Random graphs , 2000, Wiley-Interscience series in discrete mathematics and optimization.

[21]  Stephen Alstrup,et al.  Small induced-universal graphs and compact implicit graph representations , 2002, The 43rd Annual IEEE Symposium on Foundations of Computer Science, 2002. Proceedings..

[22]  Michael R. Capalbo Explicit sparse almost-universal graphs for G(n, k/n) , 2010, Random Struct. Algorithms.

[23]  Noga Alon,et al.  UNIVERSALITY AND TOLERANCE (Extended Abstract) , 2000 .

[24]  S. Janson,et al.  Upper tails for subgraph counts in random graphs , 2004 .

[25]  Noga Alon,et al.  Embedding nearly-spanning bounded degree trees , 2007, Comb..

[26]  E. Upfal,et al.  On factors in random graphs , 1981 .

[27]  Noga Alon,et al.  Sparse universal graphs for bounded‐degree graphs , 2007, Random Struct. Algorithms.