312,357 research outputs found
Renormalization Invariants and Quark Flavor Mixings
A set of renormalization invariants is constructed using approximate,
two-flavor, analytic solutions for RGEs. These invariants exhibit explicitly
the correlation between quark flavor mixings and mass ratios in the context of
the SM, DHM and MSSM of electroweak interaction. The well known empirical
relations , can
thus be understood as the result of renormalization evolution toward the
infrared point. The validity of this approximation is evaluated by comparing
the numerical solutions with the analytical approach. It is found that the
scale dependence of these quantities for general three flavoring mixing follows
closely these invariants up to the GUT scale.Comment: 23 pages, 7 figure
Logarithmic Entropy of Kehagias-Sfetsos black hole with Self-gravitation in Asymptotically Flat IR Modified Horava Gravity
Motivated by recent logarithmic entropy of Hoava-Lifshitz gravity,
we investigate Hawking radiation for Kehagias-Sfetsos black hole from tunneling
perspective. After considering the effect of self-gravitation, we calculate the
emission rate and entropy of quantum tunneling by using Kraus-Parikh-Wilczek
method. Meanwhile, both massless and massive particles are considered in this
letter. Interestingly, two types tunneling particles have the same emission
rate and entropy whose analytical formulae are and , respectively. Here, is the
Hoava-Lifshitz field parameter. The results show that the
logarithmic entropy of Hoava-Lifshitz gravity could be explained
well by the self-gravitation, which is totally different from other methods.
The study of this semiclassical tunneling process may shed light on the
understand of Hoava-Lifshitz gravity.Comment: 9 pages, revtex
FPTAS for Counting Monotone CNF
A monotone CNF formula is a Boolean formula in conjunctive normal form where
each variable appears positively. We design a deterministic fully
polynomial-time approximation scheme (FPTAS) for counting the number of
satisfying assignments for a given monotone CNF formula when each variable
appears in at most clauses. Equivalently, this is also an FPTAS for
counting set covers where each set contains at most elements. If we allow
variables to appear in a maximum of clauses (or sets to contain
elements), it is NP-hard to approximate it. Thus, this gives a complete
understanding of the approximability of counting for monotone CNF formulas. It
is also an important step towards a complete characterization of the
approximability for all bounded degree Boolean #CSP problems. In addition, we
study the hypergraph matching problem, which arises naturally towards a
complete classification of bounded degree Boolean #CSP problems, and show an
FPTAS for counting 3D matchings of hypergraphs with maximum degree .
Our main technique is correlation decay, a powerful tool to design
deterministic FPTAS for counting problems defined by local constraints among a
number of variables. All previous uses of this design technique fall into two
categories: each constraint involves at most two variables, such as independent
set, coloring, and spin systems in general; or each variable appears in at most
two constraints, such as matching, edge cover, and holant problem in general.
The CNF problems studied here have more complicated structures than these
problems and require new design and proof techniques. As it turns out, the
technique we developed for the CNF problem also works for the hypergraph
matching problem. We believe that it may also find applications in other CSP or
more general counting problems.Comment: 24 pages, 2 figures. version 1=>2: minor edits, highlighted the
picture of set cover/packing, and an implication of our previous result in 3D
matchin
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