13,090 research outputs found
Theories and Varying Fine Structure Constant
In analogy to theory, recently a new modified gravity theory, namely
the so-called theory, has been proposed to drive the current accelerated
expansion without invoking dark energy. In the present work, by extending
Bisabr's idea, we try to constrain theories with the varying fine
structure "constant", . We find that the constraints
on theories from the observational data are very
severe. In fact, they make theories almost indistinguishable from
CDM model.Comment: 12 pages, 4 figures, 1 table, revtex4; v2: discussions added, Phys.
Lett. B in press; v3: published versio
On Frankl and Furedi's conjecture for 3-uniform hypergraphs
The Lagrangian of a hypergraph has been a useful tool in hypergraph extremal
problems. In most applications, we need an upper bound for the Lagrangian of a
hypergraph. Frankl and Furedi in \cite{FF} conjectured that the -graph with
edges formed by taking the first sets in the colex ordering of
has the largest Lagrangian of all -graphs with
edges. In this paper, we give some partial results for this conjecture.Comment: 19 pages, 1 figure. arXiv admin note: substantial text overlap with
arXiv:1211.650
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