312,357 research outputs found

    Renormalization Invariants and Quark Flavor Mixings

    Full text link
    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 θ23∝ms/mb\theta_{23}\propto m_s /m_b , θ13∝md/mb\theta_{13}\propto m_d /m_b 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

    Full text link
    Motivated by recent logarithmic entropy of HorΛ‡\check{r}ava-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 Ξ“\Gamma and entropy SbS_b whose analytical formulae are Ξ“=exp⁑[Ο€(rin2βˆ’rout2t)/2+Ο€/Ξ±ln⁑rin/rout]\Gamma = \exp{[\pi (r_{in}^2 - r_{out}^2t)/2 + \pi/\alpha \ln r_{in}/r_{out}]} and Sb=A/4+Ο€/Ξ±ln⁑(A/4)S_b = A/4 + \pi/\alpha \ln (A/4), respectively. Here, Ξ±\alpha is the HorΛ‡\check{r}ava-Lifshitz field parameter. The results show that the logarithmic entropy of HorΛ‡\check{r}ava-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 HorΛ‡\check{r}ava-Lifshitz gravity.Comment: 9 pages, revtex

    FPTAS for Counting Monotone CNF

    Full text link
    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 55 clauses. Equivalently, this is also an FPTAS for counting set covers where each set contains at most 55 elements. If we allow variables to appear in a maximum of 66 clauses (or sets to contain 66 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 44. 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
    • …
    corecore