General Structure of Relativistic Vector Condensation

We study relativistic massive vector condensation due to a non zero chemical potential associated to some of the global conserved charges of the theory. We show that the phase structure is very rich. More specifically there are three distinct phases depending on the value of one of the zero chemical potential vector self interaction terms. We also develop a formalism which enables us to investigate the vacuum structure and dispersion relations in the spontaneously broken phase of the theory. We show that in a certain limit of the couplings and for large chemical potential the theory is not stable. This limit, interestingly, corresponds to a gauge type limit often employed to economically describe the ordinary vector mesons self interactions in QCD. We finally indicate for which physical systems our analysis is relevant.Comment: RevTex4 14 pages,4 figure

Risk of infections in renal cell carcinoma (RCC) and non-RCC patients treated with mammalian target of rapamycin inhibitors

Background: Mammalian target of rapamycin (mTOR) inhibitors are used in a variety of malignancies. Infections have been reported with these drugs. We performed an up-to-date meta-analysis to further characterise the risk of infections in cancer patients treated with these agents. Methods: Pubmed and oncology conferences' proceedings were searched for studies from January 1966 to June 2012. Studies were limited to phase II and III randomised controlled trials (RCTs) of everolimus or temsirolimus reporting on cancer patients with adequate safety profiles. Summary incidences, relative risks (RRs), and 95% confidence intervals (CIs) were calculated. Results: A total of 3180 patients were included. The incidence of all-grade and high-grade infections due to mTOR inhibitors was 33.1% (95% CI, 24.5–43.0%) and 5.6% (95% CI, 3.8–8.3%), respectively. Compared with controls, the RR of all-grade and high-grade infections due to mTOR inhibitors was 2.00 (95% CI, 1.76–2.28, P<0.001) and 2.60 (95% CI, 1.54–4.41, P<0.001), respectively. Subgroup analysis found no difference in incidences or risks between everolimus and temsirolimus or between different tumour types (renal cell carcinoma (RCC) vs non-RCC). Infections included respiratory tract (61.7%), genitourinary (29.4%), skin/soft tissue (4.2%), and others (4.9%). Conclusion: Treatment with mTOR inhibitors is associated with a significant increase in risk of infections. Close monitoring for any signs of infections is warranted

Tau mesonic decays and strong anomaly of PCAC

Strong anomaly of the PCAC is found in $\tau\rightarrow\omega \pi\pi\nu$ and $\omega\rho\nu$ in the chiral limit. It originates in WZW anomaly. Theoretical result of $\tau\rightarrow\omega\pi\pi\nu$ agrees with data well and the measurement of $\tau\rightarrow\omega\rho\nu$ will confirm the strong anomaly of PCAC. The strong anomaly of PCAC is studied.Comment: 27 page

Vacuum stability and the Cholesky decomposition

We discuss how the Cholesky decomposition may be used to ascertain whether a critical point of the field theory scalar potential provides a stable vacuum configuration. We then use this method to derive the stability conditions in a specific example.Comment: 7 page

Fate of Vector Dominance in the Effective Field Theory

We reveal the full phase structure of the effective field theory for QCD, based on the hidden local symmetry (HLS) through the one-loop renormalization group equation including quadratic divergences. We then show that vector dominance (VD) is not a sacred discipline of the effective field theory but rather an accidental phenomenon peculiar to three-flavored QCD. In particular, the chiral symmetry restoration in HLS model takes place in a wide phase boundary surface, on which the VD is realized nowhere. This suggests that VD may not be valid for chiral symmetry restoration in hot and/or dense QCD.Comment: 4 pages, 3 figures. One reference added. Minor modification to shorten the manuscript. This is the version to appear in Physical Review Letter

Effective chiral Lagrangians for spin-1 mesons

The commonly used types of effective theory for vector mesons are reviewed and their relationships clarified. They are shown to correspond to different choices of field for spin-1 particles and the rules for transforming between them are described. The importance of respecting chiral symmetry is stressed. The choice of fields that transform homogeneously under the nonlinear realisation of chiral symmetry imposes no preconceptions about the types of coupling for the mesons. This representation thus provides a convenient framework for relating different theories. It is also used to elucidate the nature of the assumptions in specific hidden-gauge and massive Yang-Mills models that have been widely used.Comment: 46 pages (RevTeX

Electroweak Physics for Color Superconductivity

We construct the effective theories describing the electroweak interactions for the low energy excitations associated with the color superconductive phases of QCD at high matter density. The main result, for the 3 flavor case, is that the quasiparticle Goldstone boson $\pi^0$ decay into two physical massless photons is identical to the zero density case once we use the new Goldstone decay constant and the modified electric charge $\widetilde{e}=e \cos\theta$, with $\tan\theta =2e/\sqrt{3}g_s$ and $g_s$ the strong coupling constant. For 2 flavors we find that the coupling of the quarks to the neutral vector boson $Z^0$ is modified with respect to the zero density case. We finally point out possible applications of our result to the physics of compact objects.Comment: 23 pages, 1 Figure, RevTex. More discussion and references adde

Role of Light Vector Mesons in the Heavy Particle Chiral Lagrangian

We give the general framework for adding "light" vector particles to the heavy hadron effective chiral Lagrangian. This has strong motivations both from the phenomenological and aesthetic standpoints. An application to the already observed D \rightarrow \overbar{K^*} weak transition amplitude is discussed.Comment: 19 pages, LaTeX documen

The Superfluid and Conformal Phase Transitions of Two-Color QCD

The phase structure of two-color QCD is examined as a function of the chemical potential and the number of light quark flavors. We consider effective Lagrangians for two-color QCD containing the Goldstone excitations, spin-one particles and negative intrinsic parity terms. We discuss the possibility of a conformal phase transition and the enhancement of the global symmetries as the number of flavors is increased. The effects of a quark chemical potential on the spin-one particles and on the negative intrinsic parity terms are analyzed. It is shown that the phase diagram that is predicted by the linearly realized effective Lagrangian at tree-level matches exactly that predicted by chiral perturbation theory.Comment: ReVTeX, 23 pages, 3 figures. Discussion of vector condensation extended, two figures added, references adde

The Pion Decay Constants and the Rho-Meson Mass at Finite Temperature in the Hidden Local Symmetry

We study the temperature dependence of the pion decay constant and rho-meson mass in the hidden local symmetry model at one loop. Using the standard imaginary time formalism, we include the thermal effect of rho meson as well as that of pion. We show that the pion gives a dominant contribution to the pion decay constant and rho-meson contribution slightly decreases the critical temperature. The rho-meson pole mass increases as T^4/m_\rho^2 at low temperature dominated by the pion-loop effect. At high temperature, although the pion-loop effect decreases the rho-meson mass, the rho-loop contribution overcomes the pion-loop contribution and rho-meson mass increases with temperature. We also show that the conventional parameter a is stable as the temperature increases.Comment: We added a comment on the correction to the rho-meson mass from the omega-pi loop. This is the final version to be published in Phys. Rev. D. 19 pages (LaTeX-RevTeX), 7 PostScript figure