2,047 research outputs found

    Van der Waals-like phase transition from holographic entanglement entropy in Lorentz breaking massive gravity

    Get PDF
    In this paper, phase transition of AdS black holes in lorentz breaking massive gravity has been studied in the framework of holography. We find that there is a first order phase transition(FPT) and second order phase transition(SPT) both in Bekenstein-Hawking entropy(BHE)-temperature plane and holographic entanglement entropy(HEE)-temperature plane. Furthermore, for the FPT, the equal area law is checked and for the SPT, the critical exponent of the heat capacity is also computed. Our results confirm that the phase structure of HEE is similar to that of BHE in lorentz breaking massive gravity, which implies that HEE and BHE have some potential underlying relationship.Comment: 10 pages, 10 figure

    Mutual correlation in the shock wave geometry

    Full text link
    We probe the shock wave geometry with the mutual correlation in a spherically symmetric Reissner Nordstr\"om AdS black hole on the basis of the gauge/gravity duality. In the static background, we find that the regions living on the boundary of the AdS black holes are correlated provided the considered regions on the boundary are large enough. We also investigate the effect of the charge on the mutual correlation and find that the bigger the value of the charge is, the smaller the value of the mutual correlation will to be. As a small perturbation is added at the AdS boundary, the horizon shifts and a dynamical shock wave geometry forms after long time enough. In this dynamic background, we find that the greater the shift of the horizon is, the smaller the mutual correlation will to be. Especially for the case that the shift is large enough, the mutual correlation vanishes, which implies that the considered regions on the boundary are uncorrelated. The effect of the charge on the mutual correlation in this dynamic background is found to be the same as that in the static background.Comment: 10 page

    Thermodynamics and weak cosmic censorship conjecture of the torus-like black hole

    Full text link
    After studying the energy-momentum relation of charged particles' Hamilton-Jacobi equations, we discuss the laws of thermodynamics and the weak cosmic censorship conjecture in torus-like black holes. We find that both the first law of thermodynamic as well as the weak cosmic censorship conjecture are valid in both the normal phase space and extended phase space. However, the second law of thermodynamics is only valid in the normal phase space. Our results show that the first law and weak cosmic censorship conjecture do not depend on the phase spaces while the second law depends. What's more, we find that the shift of the metric function that determines the event horizon take the same form in different phase spaces, indicating that the weak cosmic censorship conjecture is independent of the phase space.Comment: 15 page

    How tyramine β-hydroxylase controls the production of octopamine, modulating the mobility of beetles

    Get PDF
    Biogenic amines perform many kinds of important physiological functions in the central nervous system (CNS) of insects, acting as neuromodulators, neurotransmitters, and neurohormones. The five most abundant types of biogenic amines in invertebrates are dopamine, histamine, serotonin, tyramine, and octopamine (OA). However, in beetles, an important group of model and pest insects, the role of tyramine beta-hydroxylase (T beta H) in the OA biosynthesis pathway and the regulation of behavior remains unknown so far. We therefore investigated the molecular characterization and spatiotemporal expression profiles of T beta H in red flour beetles (Triboliun castaneum). Most importantly, we detected the production of OA and measured the crawling speed of beetles after dsTcT beta H injection. We concluded that TcT beta H controls the biosynthesis amount of OA in the CNS, and this in turn modulates the mobility of the beetles. Our new results provided basic information about the key genes in the OA biosynthesis pathway of the beetles, and expanded our knowledge on the physiological functions of OA in insects

    Pseudogap, Superconducting Energy Scale, and Fermi Arcs in Underdoped Cuprate Superconductors

    Full text link
    Through the measurements of magnetic field dependence of specific heat in La2−xSrxCuO4La_{2-x}Sr_xCuO_4 in zero temperature limit, we determined the nodal slope vΔv_\Delta of the quasiparticle gap. It is found that vΔv_\Delta has a very similar doping dependence of the pseudogap temperature T∗T^* or value Δp\Delta_p. Meanwhile the virtual maximum gap at (π,0\pi,0) derived from vΔv_\Delta is found to follow the simple relation Δq=0.46kBT∗\Delta_q=0.46k_BT^* upon changing the doping concentration. This strongly suggests a close relationship between the pseudogap and superconductivity. It is further found that the superconducting transition temperature is determined by both the residual density of states of the pseudogap phase and the nodal gap slope in the zero temperature limit, namely, Tc≈βvΔγn(0)T_c \approx \beta v_\Delta \gamma_n(0), where γn(0)\gamma_n(0) is the extracted zero temperature value of the normal state specific heat coefficient which is proportional to the size of the residual Fermi arc karck_{arc}. This manifests that the superconductivity may be formed by forming a new gap on the Fermi arcs near nodes below TcT_c. These observations mimic the key predictions of the SU(2) slave boson theory based on the general resonating-valence-bond (RVB) picture.Comment: 6 pages, 6 figures, to be published in Phys. Rev.
    • …
    corecore