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1.
C. Chris Wu 《Journal of statistical physics》1996,88(5-6):1399-1408
We consider an inhomogeneous contact process on a tree
of degreek, where the infection rate at any site isλ, the death rate at any site in
isδ (with 0 <δ ⩽ 1) and that at any site in
is 1. Denote by
the critical value for thehomogeneous model (i.e.,δ=1) on
and byϑ(δ, λ) the survival probability of the inhomogeneous model on
. We prove that whenk > 4, if
, a subtree embedded in
, with 1 ⩽σ ⩽ √k, then three existsδ
c
σ
strictly between (
) and 1 such that (
) whenδ >δ
c
σ
andϑ(δ, λ
c(
) > 0 whenδ <δ
c
σ
; ifS={o}, the origin of
, then
for anyδ ε (0, 1). 相似文献
2.
3.
N. M. Agababyan V. V. Ammosov M. Atayan N. Grigoryan H. Gulkanyan A. A. Ivanilov Zh. Karamyan V. A. Korotkov 《Physics of Atomic Nuclei》2006,69(1):35-38
The influence of nuclear effects on the production of neutral strange particles (V
0) is investigated using the data obtained with SKAT propane-freon bubble chamber irradiated in the neutrino beam (with E
v
=3−30 GeV) at the Serpukhov accelerator. The mean multiplicity of V
0 particles in nuclear interactions,
, is found to exceed significantly that in “quasideuteron” interactions,
. The ratio of
is larger than that for π− mesons,
. It is shown that the multiplicity gain of V
0 particles can be explained by intranuclear interactions of produced pions.
The text was submitted by the authors in English. 相似文献
4.
Summary Reflectivity measurements have been done on dopedn-type HgCr2Se4 (n≈(1015÷1019) cm−3), at various temperatures ((4÷300) K) in the infra-red range
. The spectra show the structure of a plasma edge and reststrahlbands. Data have been analysed by a Kramers-Kronig procedure.
The deduced dynamical conductivity shows an anomaly near the plasma frequency ωp. The transmitivity measurements show a strong temperature dependence of the conduction band.
Paper presented at the ?V International Conference on Ternary and Multinary Compounds?, held in Cagliari, September 14–16,
1982. 相似文献
5.
6.
We classify simple linearly compact n-Lie superalgebras with n > 2 over a field ${\mathbb{F}}We classify simple linearly compact n-Lie superalgebras with n > 2 over a field
\mathbbF{\mathbb{F}} of characteristic 0. The classification is based on a bijective correspondence between non-abelian n-Lie superalgebras and transitive
\mathbbZ{\mathbb{Z}}-graded Lie superalgebras of the form L=?j=-1n-1 Lj{L=\oplus_{j=-1}^{n-1} L_j}, where dim L
n−1 = 1, L
−1 and L
n−1 generate L, and [L
j
, L
n−j−1] = 0 for all j, thereby reducing it to the known classification of simple linearly compact Lie superalgebras and their
\mathbbZ{\mathbb{Z}}-gradings. The list consists of four examples, one of them being the n + 1-dimensional vector product n-Lie algebra, and the remaining three infinite-dimensional n-Lie algebras. 相似文献
7.
Given a one dimensional perturbed Schrödinger operator H = ? d 2/dx 2 + V(x), we consider the associated wave operators W ± , defined as the strong L 2 limits $\lim_{s\to\pm\infty}e^{isH}e^{-isH_{0}}Given a one dimensional perturbed Schr?dinger operator H = − d
2/dx
2 + V(x), we consider the associated wave operators W
± , defined as the strong L
2 limits
. We prove that W
± are bounded operators on L
p
for all 1 < p < ∞, provided
, or else
and 0 is not a resonance. For p = ∞ we obtain an estimate in terms of the Hilbert transform. Some applications to dispersive estimates for equations with
variable rough coefficients are given. 相似文献
8.
V. S. Rabinovich 《Russian Journal of Mathematical Physics》2009,16(2):300-308
We consider the class of matrix h-pseudodifferential operators Op h (a) with symbols a = (a ij ) i,j=1 N , where the coefficients a ij ∈ C ∞(? x n × ? ξ n ? C(0, 1] satisfy the estimates |? x β g6 ξ α α ij (x, ξ, h)| ? C αβ 〈ξ〉 m and 〈ξ〉 = (1 + |ξ|2)1/2 for every multi-indices α, β. We also assume that a ij (x, ξ) is analytically continued with respect to ξ to a tube domain ? n + i $ \mathcal{B} We consider the class of matrix h-pseudodifferential operators Op
h
(a) with symbols a = (a
ij
)
i,j=1N, where the coefficients a
ij
∈ C
∞(ℝ
x
n
× ℝ
ξ
n
⊗ C(0, 1] satisfy the estimates |ϖ
x
β
g6
ξ
α
α
ij
(x, ξ, h)| ⩽ C
αβ
〈ξ〉
m
and 〈ξ〉 = (1 + |ξ|2)1/2 for every multi-indices α, β. We also assume that a
ij
(x, ξ) is analytically continued with respect to ξ to a tube domain ℝ
n
+ i
, where is a bounded domain in ℝ
n
containing the origin. The main results of the paper are the local estimates for solutions of h-pseudodifferential equations.
Let H
h
s
(ℝ
n
, ℂ
N
) be the space of distributions with values in ℂ
N
which is equipped with the norm , let Ω ⊂ ℝ
n
be a bounded open set, let v ∈ C
∞(ℝ
n
), let ▿v(x) ∈ for any x ∈ Ω, and let . Let u
h
(∈ H
h
s
(ℝ
n
,‒
N
)) be a solution of the equation Op
h
(α)u = 0. In this case, for every ϕ ∈ C
0∞ (Ω) such that ϕ(x) = 1 on Supp v and for a sufficiently small h
0 > 0, there exists a constant C > 0 such that the following estimate holds for every h ∈ (0, h
0]:
We apply estimate (1) to local tunnel exponential estimates for the behavior as h → 0 of the eigenfunctions of matrix Schr?dinger, Dirac, and square-root Klein-Gordon operators.
To the memory of Professor V. A. Borovikov 相似文献
((1)) |
9.
We examine the effects of mixing induced non-diagonal light-heavy neutrino weak neutral currents on the amplitude for the
process
(with a=e, μ or τ). By imposing constraint that the amplitude should not exceed the perturbative unitarity limit at high energy
, we obtain bounds on light-heavy neutrino mixing parameter sin2
where
is the mixing angle. In the case of one heavy neutrino (mass mξ) or mass degenerate heavy neutrinos, for Λ=1 TeV, no bound is obtained for mξ<0.50 TeV. However, sin2
≤3.8 × 10−6 for mξ=5 TeV and sin
≤6.0 × 10−8 for mξ=10 TeV. For Λ=∞, no constraint is obtained for mξ<0.99 TeV and sin2
≤3.8 × 10−2 (for mξ=5 TeV) and sin2
≤9.6 × 10−3 (for mξ=10 TeV). 相似文献
10.
11.
A. I. Dmitriev V. M. Kaminski G. V. Lashkarev P. E. Butorin Z. D. Kovalyuk V. I. Ivanov A. I. Beskrovny 《Physics of the Solid State》2009,51(11):2342-2346
The neutron diffraction patterns have been analyzed for a layered single crystal and a powder of the γ-polytype of indium
selenide in the temperature range 10–300 K. In the temperature range 10–50 K, the excitation of bending vibrations due to
the charge density waves changes the phonon spectrum and gives rise to a negative thermal expansion in the plane of layers,
i.e., α‖c
= −2.2 × 10−6 K−1, which is characteristic of two-dimensional structures. The average (over the range T = 50–300 K) coefficients of thermal expansion along the principal crystallographic directions have been calculated: $
\bar \alpha _{ \bot c}
$
\bar \alpha _{ \bot c}
= 10.48 × 10−6 K−1 and $
\bar \alpha _{\parallel c}
$
\bar \alpha _{\parallel c}
= 12.97 × 10−6 K−1, which agree with the X-ray diffraction data previously obtained by the authors at T = 290 K. 相似文献
12.
On the Schrödinger equation and the eigenvalue problem 总被引:1,自引:0,他引:1
If
k
is thek
th eigenvalue for the Dirichlet boundary problem on a bounded domain in
n
, H. Weyl's asymptotic formula asserts that
, hence
. We prove that for any domain and for all
. A simple proof for the upper bound of the number of eigenvalues less than or equal to - for the operator –V(x) defined on
n
(n3) in terms of
is also provided.Research partially supported by a Sloan Fellowship and NSF Grant No. 81-07911-A1 相似文献
13.
The phenomenon of nonlinear resonance provides a mechanism for the unbounded amplification of small solutions of systems of conservation laws. We construct spatially 2-periodic solutionsu
N C
([0,t
N
] × witht
N bounded, satisfying
相似文献
14.
Exact plane-symmetric solutions of the spinor-field equation with zero mass parameter and nonlinear term that depends arbitrarily
on the S2−P2 invariant are derived with consideration of an intrinsic gravitational field. The existence of regular solutions with localized
energy density among the solutions obtained is investigated. Equations with powerlaw and polynomial nonlinearity types are
examined in detail. For the power-law nonlinearity, when the nonlinear term entering into the Lagrangian has the form LN=γIn, where γ is the nonlinearity parameter and n=const, it is shown that the initial system of Einstein and spinor-field equations
has regular solutions with localized energy density only under the conditions λ=−Λ2 < 0, n > 1. In this case, the examined field configuration posesses a negative energy. In the case of polynomial nonlinearity,
regular solutions with localized energy density T
0
0
(x), positive energy
(upon integration over y and z between finite limits), and an everywhere regular metric that transforms into a two-dimensional
space-time metric at spatial infinity are obtained. It is shown that the initial nonlinear spinor-field equations in two-dimensional
space-time have no solutions with localized energy density. Thus, it is established that the intrinsic gravitational field
plays a regularizing role in the frmation of regular localized solutions to the examined nonlinear spinor-field equations.
Russian University of People's Friendship. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 12–19,
November, 1999. 相似文献
15.
Nearly a 50% decrease of the resistivity ρ(T, x) is observed upon just 4% Cu doping at the Mn site of La2/3Ca1/3Mn1−x
CuxO3. When the observed phenomenon is attributed to a decrease of the spin-polaron energy E
σ(x) below T
C
(x), all of the data are found to be well fitted by the nonthermal coherent tunneling expression
, assuming that the magnetization in the ferromagnetic state is given by the expression
. The best fits through all the data points suggest
and E
σ(x)≃E
σ(0)(1−x)4 for the explicit x dependence of the Cu-induced modifications of the Mn-spin-dominated zero-temperature spontaneous magnetization, residual
paramagnetic contribution, and spin-polaron tunneling energy, respectively, with E
σ(0)=0.12 eV.
Pis’ma Zh. éksp. Teor. Fiz. 69, No. 11, 812–815 (10 June 1999)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
16.
In this paper, an error in the proof of Theorem 4.9 in Gudder’s paper (Int. J. Theor. Phys. 47(1):268–279, 2008) is pointed out and it is proved that if
such that E
i
∈ℂI∖{0} and E
j
∉ℂI for some i,j in {1,2,…,n}, then
.
This subject is supported by the NNSF of China (No. 10571113, 10871224). 相似文献
17.
Let S
2 be the 2-dimensional unit sphere and let J
α
denote the nonlinear functional on the Sobolev space H
1(S
2) defined by
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