118903338
Radiation Damping at a Bubble Wall
The first order phase transition proceeds via nucleation and growth of true vacuum bubbles. When charged particles collide with the bubble they could radiate electromagnetic wave. We show that, due to an energy loss of the particles by the radiation, the damping pressure acting on the bubble wall depends on the velocity of the wall even in a thermal equilibrium state.
118494859
Gravity from quantum information
We suggest that the Einstein equation can be derived from Landauer’s principle applied to an information erasing process at a local Rindler horizon and Jacobson’s idea linking the Einstein equation with thermodynamics. When matter crosses the horizon, information on the matter disappears, and the horizon entanglement entropy increases to compensate for the entropy reduction. The Einstein equation describes an information-energy relation during this process, which implies that entropic gravity is related to the quantum entanglement of the vacuum and has a quantuminformation theoretic origin.
16914311
Galactic halos as boson stars.
We investigate the boson star with the self-interacting scalar field as a model of galactic halos. The model has slightly increasing rotation curves and allows wider ranges of the mass($m$) and coupling($\lambda$) of the halo dark matter particle than the non-interacting model previously suggested(ref.\cite{sin1}). Two quantities are related by $\lambda^{\frac{1}{2}} (m_p/m)^2\st{>}{\sim} 10^{50}$.
118674685
Zero cosmological constant and nonzero dark energy from the holographic principle
The first law of thermodynamics and the holographic principle applied to an arbitrary large cosmic causal horizon are shown to naturally demand a zero cosmological constant and a non-zero dynamical dark energy in the form of the holographic dark energy. A semiclassical analysis shows that the holographic dark energy has a parameter d = 1 and an equation of state comparable to current observational data if the entropy of the horizon saturates the Bekenstein-Hawking bound. This result indicates that quantum field theory should be modified on a large scale to explain the dark energy. The relations among the dark energy, the quantum vacuum energy and the entropic gravity are also discussed.
120638209
Exclusive double charmonium production from e+ e- annihilation into two virtual photons
We calculate the contributions from QED processes involving two virtual photons to the cross sections for e + e annihilation into two charmonium states with the same C-parity. Generically, the cross sections are three orders of magnitude smaller than those for charmonia with opposite C-parity because they are suppressed by a factor of � 2 /� 2 . However, if both charmonia have quantum numbers J PC = 1 , then there is a contribution to the cross section that involves the fragmentation of each photon into a charmonium. The fragmentation contribution is enhanced by powers of Ebeam/mc, the ratio of the beam energy to the charm-quark mass, and this enhancement can compensate for the suppression factor that is associated with the coupling constants. In particular, the predicted cross section for J/ + J/ at the B factories is larger than that for J/ +�c.
39782874
Stellar Variability of the Exoplanet Hosting Star HD 63454
Of the hundreds of exoplanets discovered using the radial velocity (RV) technique, many are orbiting close to their host stars with periods less than 10 days. One of these, HD 63454, is a young active K dwarf which hosts a Jovian planet in a 2.82 day period orbit. The planet has a 14% transit probability and a predicted transit depth of 1.2%. Here we provide a re-analysis of the RV data to produce an accurate transit ephemeris. We further analyze 8 nights of time series data to search for stellar activity both intrinsic to the star and induced by possible interactions of the exoplanet with the stellar magnetospheres. We establish the photometric stability of the star at the 3 mmag level despite strong Ca II emission in the spectrum. Finally, we rule out photometric signatures of both star-planet magnetosphere interactions and planetary transit signatures. From this we are able to place constraints on both the orbital and physical properties of the planet.
118610109
The Sub-Saturn Mass Transiting Planet HAT-P-12b
We present new photometric data of the transiting planet HAT-P-12b observed in 2011. Our three transit curves are modeled using the JKTEBOP code and adopting the quadratic limb-darkening law. Including our measurements, 18 transit times spanning about 4.2 yr were used to determine the improved ephemeris with a transit epoch of 2,454,187.85560 ± 0.00011 BJD and an orbital period of 3.21305961 ± 0.00000035 days. The physical properties of the star-planet system are computed using empirical calibrations from eclipsing binary stars and stellar evolutionary models, combined with both our transit parameters and previously known spectroscopic results. We found that the absolute dimensions of the host star are M A = 0.73 ± 0.02 M ☉, R A = 0.70 ± 0.01 R ☉, log g A = 4.61 ± 0.02, ρA = 2.10 ± 0.09 ρ☉, and L A = 0.21 ± 0.01 L ☉. The planetary companion has M b = 0.21 ± 0.01 M Jup, R b = 0.94 ± 0.01 R Jup, log g b = 2.77 ± 0.02, ρb = 0.24 ± 0.01 ρJup, and T eq = 960 ± 14 K. Our results agree well with standard models of irradiated gas giants with a core mass of 11.3 M ⊕.
9155056
Radion Phenomenology in the Randall Sundrum Scenario
Phenomenology of a radion (�) in the Randall-Sundrum scenario is discussed. The radion couples to the trace of energy momentum tensor of the standard model with a strength suppressed only by a new scale (��) which is an order of the electroweak scale. In particular, the effective coupling of a radion to two gluons is enhanced due to the trace anomaly of QCD. Therefore, its production cross section at hadron colliders could be enhanced, and the dominant decay mode of a relatively light radion is � → gg, unlike the SM Higgs boson case. � +
119107944
Singlino-driven electroweak baryogenesis in the next-to-MSSM
Abstract We explore a new possibility of electroweak baryogenesis in the next-to-minimal supersymmetric standard model. In this model, a strong first-order electroweak phase transition can be achieved due to the additional singlet Higgs field. The new impact of its superpartner (singlino) on the baryon asymmetry is investigated by employing the closed-time-path formalism. We find that the CP violating source term fueled by the singlino could be large enough to generate the observed baryon asymmetry of the Universe without any conflicts with the current constraints from the non-observation of the thallium, neutron and mercury electric dipole moments.