866 research outputs found
Singlet-triplet Crossover in the Two-dimensional Dimer Spin System YbAl3C3
Low-temperature magnetization (M) measurements down to 0.1 K have been
performed in magnetic fields up to 14.5 T for a single piece of a tiny
single-crystalline sample (0.2 mg weight) of the spin-gap system YbAl3C3. At
the base temperature of 0.1 K, several metamagnetic transitions were clearly
observed for H // c in the range 6 T < H < 9 T whereas only two transitions
were observed, one at 4.8 T and the other at 6.6 T, for H // a. At fields above
9 T, the magnetization becomes almost saturated for both H // a and H // c. The
present results indicate that a singlet-triplet crossover occurs in a
relatively narrow field range, suggesting a rather weak interdimer interaction
in spite of the nearly triangular lattice of Yb ions.Comment: 5 pages, 6 figures, proceedings of ICM 201
Consistency between causality and complementarity guaranteed by the Robertson inequality in quantum field theory
It has long been debated whether gravity should be quantized or not.
Recently, the authors in [Sci. Rep. 6, 22777 (2016); Proc. Natl. Acad. Sci.
U.S.A. 106, 3035 (2009)] discussed the inconsistency between causality and
complementarity in a Gedankenexperiment involving the quantum superposition of
massive/ charged bodies, and Belenchia et al. [Phys. Rev. D 98, 126009 (2018);
Int. J. Mod. Phys. D 28, 1943001 (2019)] resolved the inconsistency by
requiring the quantum radiation and vacuum fluctuations of
gravitational/electromagnetic field. Stimulated by their works, we reanalyze
the consistency between the two physical properties, causality and
complementarity, according to the quantum field theory. In this analysis, we
consider a Gedankenexperiment inspired by [Sci. Rep. 6, 22777 (2016); Proc.
Natl. Acad. Sci. U.S.A. 106, 3035 (2009); Phys. Rev. D 98, 126009 (2018); Int.
J. Mod. Phys. D 28, 1943001 (2019)], in which two charged particles coupled
with a photon field are in a superposition of two trajectories. First, we
observe that causality is satisfied by the retarded propagation of the photon
field. Next, by introducing an inequality between visibility and which-path
information, we show that the quantum radiation and vacuum fluctuations of the
photon field ensure complementarity. We further find that the Robertson
inequality associated with the photon field leads to the consistency between
causality and complementarity in our Gedankenexperiment. Finally, we mention
that a similar feature appears in the quantum field of gravity.Comment: 14 pages, 3 figure
Quantum uncertainty of gravitational field and entanglement in superposed massive particles
Investigating the quantum nature of gravity is an important issue in modern
physics. Recently, studies pertaining to the quantum superposition of
gravitational potential have garnered significant interest. Inspired by Mari
\textit{et al.} [Sci. Rep. {\bf 6} 22777 (2016)] and Baym and Ozawa [Proc.
Natl. Acad. Sci. U.S.A. {\bf 106}, 3035 (2009)], Belenchia \textit{et al.}
[Phys. Rev. D {\bf 98}, 126009 (2018)] considered a gedanken experiment
involving such a quantum superposition and mentioned that the superposition
renders causality and complementarity inconsistent. They resolved this
inconsistency by considering the quantized dynamical degrees of freedom of
gravity. This suggests a strong relationship between the quantum superposition
of the gravitational potential and the quantization of the gravitational field.
In our previous study [Phys. Rev. D {\bf 106}, 125002 (2022)], we have shown
that the quantum uncertainty of a field guarantees the consistency between
causality and complementarity. In this study, we focus on the entanglement
between two particles' states due to the electromagnetic/gravitational
potential and investigate its relationship with quantum uncertainty, causality,
and complementarity. Our numerical analyses show that the quantum uncertainty
of the electromagnetic/gravitational field results in vacuum fluctuations and
prohibits the entanglement between two particles' states when causality is
satisfied. We further demonstrate that complementarity holds when the particles
do not get entangled. The uncertainty relation does not cause the entanglement
between two particles' states, which guarantees complementarity.Comment: 15pages, 5 figure
Successful treatment of corneal wasp sting-induced panuveitis with vitrectomy
BACKGROUND: This study aims to present the management and clinical findings of a case of corneal wasp sting and to report the outcome of corneal change and panuveitis after vitrectomy. FINDINGS: Clinical findings, anterior segment photographs, corneal endothelial changes, and medical treatment of corneal wasp sting-induced panuveitis are presented. A 95-year-man was stung by a wasp on his left cornea. A severe conjunctival hyperemia, marked corneal edema, corneal epithelial defect, and uveitis developed. As soon as the patient visited our clinic, topical corticosteroid and antibiotics were given, but corneal endothelial damage and uveitis did not improve. Anterior chamber irrigation was performed with oxiglutatione solution to rinse out the wasp venom. Corneal edema and anterior uveitis improved but the endothelial cell density gradually decreased and the vitreous opacity deteriorated. Therefore, a 23-gauge vitrectomy was performed. Subsequently, the corneal edema and panuveitis improved. CONCLUSIONS: Vitrectomy may be an effective treatment for corneal endothelial damage and endophthalmitis induced by a corneal wasp sting
Transformation of peptide nanotubes into a vesicle via fusion driven by stereo-complex formation.
Two types of peptide nanotubes, one is prepared from an amphiphilic peptide having a right-handed helix segment and the other from that having a left-handed helix segment, are shown to transform the morphology into a vesicle by membrane fusion due to stereo-complex formation between these helical segments
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