Title
The Approximate Loebl-Komlós-Sós Conjecture I: The Sparse Decomposition.
Abstract
In a series of four papers we prove the following relaxation of the Loebl-Komlos-Sos conjecture: For every alpha > 0 there exists a number k(0) such that for every k > k(0), every n-vertex graph G with at least (1/2 + alpha) n vertices of degree at least (1 + alpha)k contains each tree T of order k as a subgraph. The method to prove our result follows a strategy similar to approaches that employ the Szemeredi regularity lemma: We decompose the graph G, find a suitable combinatorial structure inside the decomposition, and then embed the tree T into G using this structure. Since for sparse graphs G, the decomposition given by the regularity lemma is not helpful, we use a more general decomposition technique. We show that each graph can be decomposed into vertices of huge degree, regular pairs (in the sense of the regularity lemma), and two other objects each exhibiting certain expansion properties. In this paper, we introduce this novel decomposition technique. In the three follow-up papers, we find a suitable combinatorial structure inside the decomposition, which we then use for embedding the tree.
Year
DOI
Venue
2017
10.1137/140982842
SIAM JOURNAL ON DISCRETE MATHEMATICS
Keywords
DocType
Volume
extremal graph theory,Loebl-Komlos-Sos conjecture,tree embedding,regularity lemma,sparse graph,graph decomposition
Journal
31
Issue
ISSN
Citations 
2
0895-4801
0
PageRank 
References 
Authors
0.34
0
6
Name
Order
Citations
PageRank
Jan Hladký111318.59
János Komlós21254255.25
Diana Piguet3127.65
Miklós Simonovits457898.20
maya stein58115.65
Endre Szemerédi62102363.27