Entangling macroscopic diamonds at room temperature: Bounds on the continuous-spontaneous-localization parameters

A recent experiment [K. C. Lee et al., Science 334, 1253 (2011)] succeeded in detecting entanglement between two macroscopic specks of diamonds, separated by a macroscopic distance, at room temperature. This impressive results is a further confirmation of the validity of quantum theory in (at least parts of) the mesoscopic and macroscopic domain, and poses a challenge to collapse models, which predict a violation of the quantum superposition principle, which is the bigger the larger the system. We analyze the experiment in the light of such models. We will show that the bounds placed by experimental data are weaker than those coming from matter-wave interferometry and non-interferometric tests of collapse models.Comment: 7 pages, 3 figures, v2: close to the published version, LaTe

Two- and four-quasiparticle states in the interacting boson model: Strong-coupling and decoupled band patterns in the SU(3) limit

An extension of the interacting boson approximation model is proposed by allowing for two- and four-quasiparticle excitations out of the boson space. The formation of band patterns based on two- and four-quasiparticle states is investigated in the SU(3) limit of the model. For hole-type (particle-type) fermions coupled to the SU(3) prolate (oblate) core, it is shown that the algebraic K-representation basis, which is the analog of the strong-coupling basis of the geometrical model, provides an appropriate description of the low-lying two-quasiparticle bands. In the case of particle-type (hole-type) fermions coupled to the SU(3) prolate (oblate) core, a new algebraic decoupling basis is derived that is equivalent in the geometrical limit to Stephens’ rotation-aligned basis. Comparing the wave functions that are obtained by diagonalization of the model Hamiltonian to the decoupling basis, several low-lying two-quasiparticle bands are identified. The effects of an interaction that conserves only the total nucleon number, mixing states with different number of fermions, are investigated in both the strong-coupling and decoupling limits. All calculations are performed for an SU(3) boson core and the h11/2 fermion orbital

Two-quasiparticle states in the interacting boson model. II. Electromagnetic properties in the SU(3) limit

The interacting boson approximation model, extended by allowing one boson to break and form a quasiparticle pair, is investigated in the SU(3) limit. Electromagnetic properties of yrast states are studied for the algebraic analogs of both the decoupling and strong-coupling limits. The effects of a pair-breaking interaction that mixes states with different numbers of quasiparticles are investigated for E2 transitions between yrast states. For the algebraic analog of the decoupling limit, it is shown that the mixing interaction has a strong influence on transitions in the region of crossing between the ground-state band and the lowest two-quasiparticle (2qp) band. The mixing interaction does not change the electromagnetic properties of the states of the ground-state band. This effect is due to the approximate cancellation between self-energy and vertex corrections, which corresponds to the nuclear Ward identity. For the algebraic analog of the strong-coupling limit, the K forbiddeness of E2 transitions between the ground-state band and the lowest 2qp band is high, and therefore the influence of the mixing interaction is negligible

Generalized seniority scheme in light Sn isotopes

The yrast generalized seniority states are compared with the corresponding shell model states for the case of the Sn isotopes $^{104-112}$Sn. For most of the cases the energies agree within 100 keV and the overlaps of the wave functions are greater than 0.7.Comment: 8 pages, revtex. Submitted to Phys. Rev.

Possible Photometric Evidence of Ejection of Bullet Like Features in the Relativistic Jet source SS433

SS433 is well-known for its precessing twin jets having optical bullets inferred through {\it spectroscopic} observation of $H_\alpha$ lines. Recently, Chakrabarti et al. (2002) described processes which may be operating in accretion disk of SS433 to produce these bullets. In a recent multi-wavelength campaign, we find sharp rise in intensity in time-scales of few minutes in X-rays, IR and radio waves through {\it photometric} studies. We interpret them to be possible evidence of ejection of bullet-like features from accretion disks.Comment: 9 latex pages with five figure

Excited states in Sm139 described with the interacting boson model plus broken pairs

The high-spin structure of Sm139 has been studied through the Pd110(34S,5n) reaction at beam energies of 150 and 165 MeV. The level scheme has been extended up to an excitation energy of 11.1 MeV and spin 61/2+. A band built on the νi13/2 [660]1/2+ intruder orbital has been established and firmly linked to the known lower-spin levels in the nucleus. The low-lying states of both parities as well as a relatively strong ΔI=1 regular structure observed above spin 27/2- are nicely reproduced by the interacting boson-fermion model with broken pairs

Clade, Country and Region-specific HIV-1 Vaccines: Are they necessary?

Today, scientists are often encouraged to custom-design vaccines based on a particular country or clade. Here, we review the scientific literature and then suggest that the overwhelming endeavor to produce a unique vaccine for every world region or virus subtype may not be necessary