1,076,573 research outputs found
Long range statistical fluctuations of the crossed Josephson current
We investigate the crossed Josephson effect in a geometry consisting of a
double ferromagnetic bridge between two superconductors, with tunnel
interfaces. The crossed Josephson current vanishes on average because the
Andreev reflected hole does not follow the same sequence of impurities as the
incoming electron. We show that i) the root mean square of the crossed
Josephson current distribution is proportional to the square root of the
junction area; and ii) the coherent coupling mediated by fluctuations is ``long
range'' since it decays over the ferromagnet phase coherence length ,
larger than the exchange length. We predict a crossed Josephson current due to
fluctuations if the length of the ferromagnets is smaller than and
larger than the exchange length .Comment: 8 pages, 3 figures, modifications in the presentatio
A Non-supersymmetric Large N CFT from Type 0 String Theory
We show that type 0B theory has a classical AdS_5 x S^5 solution and argue
that it is stable at the string-theory level for small enough radius. The dual
4-d conformal field theory is the infrared limit of the theory on N electric
D3-branes coincident with N magnetic D3-branes. We explicitly construct this
SU(N) x SU(N) gauge theory with global SO(6) symmetry and verify that the
one-loop term in the beta function vanishes exactly, while the two-loop term
vanishes in the large N limit. We find that this theory is related by a certain
projection to the maximally supersymmetric Yang-Mills theory suggesting its
large N conformal invariance to all orders in perturbation theory.Comment: 15 pages, harvmac. v2: references and a note on renormalization of
Yukawa and scalar couplings added; v3: a note on orbifold interpretation
added; the version to appear in JHE
Pressure-induced spin-state transition of iron in magnesiow\"ustite (Fe,Mg)O
We present a detailed theoretical study of the electronic, magnetic, and
structural properties of magnesiow\"ustite FeMgO with in the
range between 00.875 using a fully charge self-consistent implementation of
the density functional theory plus dynamical mean-field theory (DFT+DMFT)
method. In particular, we compute the electronic structure and phase stability
of the rock-salt B1-structured (Fe,Mg)O at high pressures relevant for the
Earth's lower mantle. We obtain that upon compression paramagnetic (Fe,Mg)O
exhibits a spin-state transition of Fe ions from a high-spin to low-spin
(HS-LS) state which is accompanied by a collapse of local magnetic moments. The
HS-LS transition results in a substantial drop of the lattice volume by about
48 %, implying a complex interplay between electronic and lattice degrees of
freedom. Our results reveal a strong sensitivity of the calculated transition
pressure upon addition of Mg. While for Fe-rich
magnesiow\"ustite, Mg , exhibits a rather weak variation
at 80 GPa, for Fe-poor (Fe,Mg)O it drops, e.g., by about 35 % to 52 GPa
for Mg . This behavior is accompanied by a substantial change of the
spin transition range from 50140 GPa in FeO to 3090 GPa for . In
addition, the calculated bulk modulus (in the HS state) is found to increase by
12 % from 142 GPa in FeO to 159 GPa in (Fe,Mg)O with Mg . We
find that the pressure-induced HS-LS transition has different consequences for
the electronic properties of the Fe-rich and poor (Fe,Mg)O. For the Fe-rich
(Fe,Mg)O, the transition is found to be accompanied by a Mott insulator to
(semi-) metal phase transition. In contrast to that, for , (Fe,Mg)O
remains insulating up to the highest studied pressures, implying a Mott
insulator to band insulator phase transition at the HS-LS transformation.Comment: 9 pages, 9 figure
KEDUDUKAN AHLI WARIS NON MUSLIM DALAM KEWARISAN ISLAM (STUDI KASUS PUTUSAN NOMOR : 1578/PDT.G/2010/PA.JT)
Salah satu pembahasan dalam ilmu mawaris adalah pembahasan
tentang penghalang dalam kewarisan. Penghalang dalam kewarisan ada
tiga penyebabnya yaitu pembunuhan yang disengaja, beda agama dan
perbudakan. Beda agama adalah apabila antara ahli waris dan pewaris
salah satunya beragama Islam dan yang lain tidak beragama Islam.
Tentang perbedaan agama antara pewaris dan ahli waris, dapat
menggugurkan hak seseorang untuk mewarisi harta peninggalan.
Rumusan masalah dalam penelitian ini ialah bagaimana kedudukan
ahli waris non muslim dalam kewarisan Islam dan apakah pertimbangan
Hakim dalam putusan nomor : 1578/Pdt.G/2010/PA.JT telah sesuai
dengan hukum Islam serta Kompilasi Hukum Islam.
Metode pendekatan yang digunakan peneliti adalah library
research (yurudis normatif). Yaitu suatu pendekatan alternatif yang
menganalisa bahan-bahan pustaka di bidang hukum yang norma-
normanya tertulis dan spesifikasi penelitian deskriptis analitis, yaitu
dengan menggunakan metode dan teori ilmu-ilmu sosial tentang hukum
untuk membantu peneliti dalam melakukan analisis.
Hasil dari penelitian ini diperoleh kesimpulan yakni : (1) Hukum
Islam menegaskan prinsip dalam kewarisan bahwa ahli waris non muslim
tidak mempunyai kedudukan untuk mewarisi harta dari pewaris muslim,
sebagaimana yang telah diatur dalam Al-Qurâan, Hadits serta Kompilasi
Hukum Islam. (2) Dalam pertimbangan hakim Pengadilan Agama Jakarta
Timur dianggap telah terjadi kekeliruan mengenai pemahaman tentang
kompetensi absolut Pengadilan Negeri Jakarta Timur yang menetapkan
masalah kewarisan Islam, karena pada dasarnya yang mempunyai
kewenangan absolut ialah Pengadilan Agama Jakarta Timur. Hal tersebut
menimbulkan dasar penolakan hakim Pengadilan Agama menolak
gugatan perkara ahli waris, yang menyebabkan ahli waris non muslim
memperoleh kembali hak kewarisannya. Hasil dari putusan tersebut
ditinjau secara sudut pandang Islam sangat bertentangan dengan Al-
Qurâan dan Hadits serta ketentuan menurut perspektif Kompilasi Hukum
Islam, bahwa mengenai sistem kewarisan Islam tidak mengakui ahli waris
non muslim sebagai ahli waris dari pewaris muslim
Quasiclassical Green function in an external field and small-angle scattering
The quasiclassical Green functions of the Dirac and Klein-Gordon equations in
the external electric field are obtained with the first correction taken into
account. The relevant potential is assumed to be localized, while its spherical
symmetry is not required. Using these Green functions, the corresponding wave
functions are found in the approximation similar to the Furry-Sommerfeld-Maue
approximation. It is shown that the quasiclassical Green function does not
coincide with the Green function obtained in the eikonal approximation and has
a wider region of applicability. It is illustrated by the calculation of the
small-angle scattering amplitude for a charged particle and the forward photon
scattering amplitude. For charged particles, the first correction to the
scattering amplitude in the non-spherically symmetric potential is found. This
correction is proportional to the scattering angle. The real part of the
amplitude of forward photon scattering in a screened Coulomb potential is
obtained.Comment: 20 pages, latex, 1 figur
Exciton Condensate Modulation in Electron-Hole Bilayers: A Real-Space Visualization
We study the texture of the exciton condensate at low temperatures in an
independently gated electron-hole bilayer system. A model Hamiltonian is solved
in real space within a mean-field approximation. It is found that, with
increased electron-hole density polarization, the system experiences phase
transformations from the zero center-of-mass momentum superfluid state, through
one- and two-dimensional exciton pair modulated states, into the normal state.
At weak density polarization, the modulating state resembles the
Larkin-Ovchinikov state in superconductors in the presence of an exchange field
in the weak-coupling BCS limit, and becomes stripe-like in the strong coupling
BEC limit. In the one-dimensional modulated phase, the density of states
exhibits low-energy intra-gap resonance quasiparticle states, which are
localized in the nodal region.Comment: 4+ pages, 6 eps figure
Possible quantum kinematics. II. Non-minimal case
The quantum analogs of the N-dimensional Cayley-Klein spaces with different
combinations of quantum and Cayley-Klein structures are described for
non-minimal multipliers, which include the first and the second powers of
contraction parameters in the transformation of deformation parameter. The
noncommutative analogs of (N-1)-dimensional constant curvature spaces are
introduced. Part of these spaces for N=5 are interpreted as the noncommutative
analogs of (1+3) space-time models. As a result the wide variety of the quantum
deformations of realistic kinematics are suggested.Comment: 13 pages, no figure
The low temperature Fulde-Ferrell-Larkin-Ovchinnikov phases in 3 dimensions
We consider the nature of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phases
in three dimensions at low temperature. We introduce a new method to handle the
quasiclassical equations for superconductors with space dependent order
parameter, which makes use of a Fourier expansion. This allows us to show that,
at T=0, an order parameter given by the linear combination of three cosines
oscillating in orthogonal directions is preferred over the standard single
cosine solution. The transition from the normal state to this phase is first
order, and quite generally the transition below the tricritical point to the
FFLO phases is always first order.Comment: 4 pages, revtex, 1 figur
Vortex tilt modulus in Fulde-Ferrell-Larkin-Ovchinnikov state
Vortex tilt response in Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) vortex
lattice is theoretically examined as a probe reflecting the spatial structure
of this state. In the FFLO state with nodal planes perpendicular to the
magnetic field in a quasi 2D material under a parallel field, the tilt modulus
E_{2} {\it of the nodal planes} decreases as the paramagnetic effect is
effectively enhanced, and this reduction of E_{2} in turn reduces the vortex
tilt modulus. This reduction of vortex tilt modulus, more remarkable in more
anisotropic systems, accompanying the FFLO transition may be an origin of the
monotonous reduction of sound velocity detected upon cooling in a ultrasound
measurement for CeCoIn5.Comment: 14 pages, 5 figures. Accepted for publication in Phys. Rev.
Radio and optical orientations of galaxies
We investigate the correlations between optical and radio isophotal position
angles for 14302 SDSS galaxies with magnitudes brighter than 18 and which
have been associated with extended FIRST radio sources. We identify two
separate populations of galaxies using the colour, concentration and their
principal components. Surprisingly strong statistical alignments are found:
late-type galaxies are overwhelmingly biased towards a position angle
differences of and early-type galaxies to . The
late-type alignment can be easily understood in terms of the standard picture
in which the radio emission is intimately related to areas of recent
star-formation. In early-type galaxies the radio emission is expected to be
driven by accretion on to a nuclear black hole. We argue that the observed
correlation of the radio axis with the minor axis of the large-scale stellar
distribution gives a fundamental insight into the structure of elliptical
galaxies, for example, whether or not the nuclear kinematics are decoupled form
the rest of the galaxy. Our results imply that the galaxies are oblate
spheroids with their radio emission aligned with the minor axis. Remarkably the
strength of the correlation of the radio major axis with the optical minor axis
depends on radio loudness. Those objects with a low ratio of FIRST radio flux
density to total stellar light show a strong minor axis correlation while the
stronger radio sources do not. This may reflect different formation histories
for the different objects and we suggest we may be seeing the different
behaviour of rationally supported and non-rotationally supported ellipticals.Comment: Version to appear in MNRA
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