共查询到20条相似文献,搜索用时 234 毫秒
1.
Anna Jenčcová 《Communications in Mathematical Physics》2006,266(1):65-70
We show a relation between a quantum channel Φ and its conjugate Φ
C
, which implies that the p → p Schatten norm of the channel is the same as the 1 → p completely bounded norm of the conjugate. This relation is used to give an alternative proof of the multiplicativity of both norms. 相似文献
2.
G. J. Gounaris J. Layssac F. M. Renard 《Zeitschrift fur Physik C Particles and Fields》1995,69(1):505-512
We discuss possible New Physics (NP) effects on the processesγγ →W
+
W
−,ZZ, Zγ, γγ, HH which are observable inγγ collisions. Such collisions may be achieved through laser backscattering at a high energye
+
e
− linear collider. To the extent that no new particles will be directly produced in the future colliders, it has already been
emphasized that the new physics possibly hidden in the bosonic interactions, may be represented by the sevendim=6 operatorsO
W,O
BΦ,O
WΦ,O
UB,O
UW
and
(the last two ones being CP-violating). In this paper, we show that the above processes are sensitive to NP scales at the
several TeV range, and we subsequently discuss the possibility to disentangle the effects of the various operators.
Partially supported by the EC contract CHRX-CT94-0579 相似文献
3.
4.
A. N. Ivanov H. Oberhummer N. I. Troitskaya M. Faber 《The European Physical Journal A - Hadrons and Nuclei》2000,8(2):223-250
A dynamics of low-energy nuclear forces is investigated for low-energy electromagnetic and weak nuclear reactions with the
deuteron in the Nambu-Jona-Lasinio model of light nuclei by example of the neutron-proton radiative capture (M1-capture) n
+ p → D + γ, the photomagnetic disintegration of the deuteron γ + D → n + p and weak reactions of astrophysical interest. These are the solar proton burning p + p → D + e+ + ν
e, the pep-process p + e− + p → D + ν
e and the neutrino and antineutrino disintegration of the deuteron caused by charged ν
e + D → e− + p + p, + D → e+ + n + n and neutral ν
e() + D → ν
e() + n + p weak currents. 相似文献
5.
We address the decay of the norm of weak solutions to the 2D dissipative quasi-geostrophic equation. When the initial data
θ0 is in L
2 only, we prove that the L
2 norm tends to zero but with no uniform rate, that is, there are solutions with arbitrarily slow decay. For θ0 in L
p
∩ L
2, with 1 ≤ p < 2, we are able to obtain a uniform decay rate in L
2. We also prove that when the norm of θ0 is small enough, the L
q
norms, for , have uniform decay rates. This result allows us to prove decay for the L
q
norms, for , when θ0 is in .
The second author was partially supported by NSF grant DMS-0600692. 相似文献
6.
R. T. Glassey 《Communications in Mathematical Physics》1977,53(1):9-18
The asymptotic behavior of solutions to the Cauchy problem for the equation $$i\psi _\imath = \frac{1}{2}\Delta \psi - \upsilon (\psi )\psi , \upsilon = r^{ - 1} *|\psi |^2 ,$$ and for systems of similar form, is studied. It is shown that the norms $$\parallel \psi (t)\parallel _{L_2 (|x| \leqq R)}^2 + \parallel \nabla \psi (t)\parallel _{L_2 (|x| \leqq R)}^2 $$ are integrable in time for any fixedR>0, from which it follows that $$\mathop {\lim }\limits_{t \to \infty } \parallel \psi (t)\parallel _{L_2 (|x| \leqq R)} = 0.$$ \] Nevertheless, it is established that anL 2-scattering theory is impossible. 相似文献
7.
Stability of planar stationary solutions to the compressible Navier-Stokes equation on the half space
under outflow boundary condition is investigated. It is shown that the planar stationary solution is stable with respect to small perturbations in
with s≥ [n/2]+1 and the perturbations decay in L
∞ norm as t →∞, provided that the magnitude of the stationary solution is sufficiently small. The stability result is proved by the energy method. In the proof an energy functional based on the total energy of the system plays an important role. 相似文献
8.
The correlations of the linear and circular polarizations in the system of two photons have been theoretically investigated.
The polarization of a two-photon state is described by the one-photon Stokes parameters and by the components of the correlation
“tensor” in the Stokes space. It is shown that in the case of two-photon decays π0 → 2γ, η → 2γ, K
L
0 → 2γ, K
S
0 → 2γ and the cascade process |0〉 → |1〉 + γ → |0〉 + 2γ(|0〉 and |1〉 are states with the spin 0 and 1, respectively) the final
two-photon state represents a characteristic example of the entangled (nonfactorizable) state, and the correlations between
the Stokes parameters in all these decays have the purely quantum character: the incoherence inequalities of the Bell type
for the components of the correlation “tensor”, established previously for the case of classical “mixtures”, are violated.
The general analysis of the registration procedure for two correlated photons by two one-photon detectors is performed. 相似文献
9.
Defining the ratiosr
p
=σ(vp →vx)/σ(vp →μ
−
x) and
we obtain the bounds 0.28 ⩽r
p
⩽ 0.61 and
using only the parton model and the data of CDHS group with iron target. We also give the complete set of parton-model relations
which would allow the determination of all the neutral-current coupling constants from inclusive cross sections alone. 相似文献
10.
Jürg Fröhlich B. Lars G. Jonsson Enno Lenzmann 《Communications in Mathematical Physics》2007,274(1):1-30
We study the nonlinear equation
which is known to describe the dynamics of pseudo-relativistic boson stars in the mean-field limit. For positive mass parameters,
m > 0, we prove existence of travelling solitary waves, , for some and with speed |v| < 1, where c = 1 corresponds to the speed of light in our units. Due to the lack of Lorentz covariance, such travelling solitary waves
cannot be obtained by applying a Lorentz boost to a solitary wave at rest (with v = 0). To overcome this difficulty, we introduce and study an appropriate variational problem that yields the functions as minimizers, which we call boosted ground states. Our existence proof makes extensive use of concentration-compactness-type
arguments.
In addition to their existence, we prove orbital stability of travelling solitary waves and pointwise exponential decay of in x. 相似文献
11.
Xiao-Gang He Xue-Qian Li Xiang Liu Jian-Ping Ma 《The European Physical Journal C - Particles and Fields》2007,49(3):731-736
Recently the BES collaboration has announced the observation of a resonant state in the π+π-η’ spectrum in J/ψ→γπ+π-η’ decay. Fitting the data with a 0-+ state, the mass is determined to be 1833.7 MeV with 7.7σ statistic significance. This state is consistent with the one extracted
from previously reported pp̄ threshold enhancement data in J/ψ→γpp̄. We study the properties of this state using QCD anomaly
and QCD sum rules, assuming X(1835) to be a pseudoscalar, and we show that it is consistent with the data. We find that this
state has a sizeable matrix element , leading to branching ratios of (2.61–7.37)×10-3 and (2.21–10.61)×10-2 for J/ψ→γGp and for Gp→π+π-η′, respectively. Combining the calculated branching ratio of J/ψ→γGp and data on threshold enhancement in J/ψ→γpp̄, we determine the coupling for the Gp–p–p̄ interaction. We finally study the branching ratios of the other J/ψ→γ+three mesons decay modes. We find that J/ψ→γGp→γ(π+π-η,KKπ0) can provide useful tests for the mechanism proposed.
PACS 11.55.Hx; 12.39.Fe; 12.39.Mk; 13.25.Gv 相似文献
12.
Saebyok Bae Byungchul Chung P. Ko 《The European Physical Journal C - Particles and Fields》2008,54(4):601-616
The CP violating phases in soft SUSY breaking terms may induce indirect CP violation in the neutral Higgs boson sector through
SUSY particle loops as well as direct CP violation in the γγ→Hi (i=1,2,3) through CP violating vertices. We present a complete analysis of the MSSM Higgs sector CP violation at photon colliders
including the chargino loop contributions in the regime , where the CP violating mixing in the neutral Higgs sector is very strongly influenced by the scalar top loop, more so than
the chargino and neutralino ones. However, the CP violating phases of the higgsino and wino mass parameters may still generate
direct CP violation in γγ→Hi. In this process, the CP violating phenomena become very rich, and thus we study the production rates and polarization asymmetries
in the Higgs production in detail. Photon colliders with high luminosity and well controlled polarized initial photon beams
are indispensable in determining the CP properties of neutral Higgs bosons.
PACS 14.80.Cp; 12.60.Jv; 11.30.Er 相似文献
13.
H. Prakash P. Kumar 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,46(2):359-363
We study amplitude-squared squeezing of the Hermitian operator Zθ=Z1
cosθ+Z2 sin θ, in the most general superposition state
, of two coherent states
and
. Here operators Z1,2 are defined by
, a is annihilation operator, θ is angle, and
complex numbers C1,2 , α, β are arbitrary and only
restriction on these is the normalization condition of the state
. We define the condition for a state
to be amplitude-squared squeezed for the operator Zθ
if squeezing parameter
, where N=a+a and
. We find
maximum amplitude-squared squeezing of Zθ in the superposed
coherent state
with minimum value 0.3268 of the
parameter S for an infinite combinations with α- β= 2.16
exp [±i(π/4) + iθ/2],
and with
arbitrary values of (α+β) and θ. For this minimum
value of squeezing parameter S, the expectation value of photon number can
vary from the minimum value 1.0481 to infinity. Variations of the parameter
S with different variables at maximum amplitude-squared squeezing are also
discussed. 相似文献
14.
A scenario that removes the contradiction between the suppression of the η(1475) → γγ decay width and the strong coupling
of η(1475) to the ρρ, ωω, and γρ0 channels and which leads to a nontrivial prediction for the manifestation of η(1475) in γγ*(Q
2) collisions is considered. Data on the dependence of the cross section for the reaction γγ*(Q
2) → K[`(K)]pK\bar K\pi on the photon virtuality in the energy range 1.35–1.55 GeV are explained here by the production of an η(1475) resonance in
contrast to their standard interpretation in terms of the f
1(1420) resonance. Experimental verification of the present explanation requires determining the spin-parity of resonance contributions,
R, in the reactions γγ*(Q
2) R → R → K[`(K)]pK\bar K\pi and J/ψ → γR → γ(γρ0, γϕ). 相似文献
15.
Extensions of Lieb’s Concavity Theorem 总被引:3,自引:1,他引:2
Frank Hansen 《Journal of statistical physics》2006,124(1):87-101
The operator function (A,B)→ Trf(A,B)(K
*)K, defined in pairs of bounded self-adjoint operators in the domain of a function f of two real variables, is convex for every Hilbert Schmidt operator K, if and only if f is operator convex. We obtain, as a special case, a new proof of Lieb’s concavity theorem for the function (A,B)→ TrA
p
K
*
B
q
K, where p and q are non-negative numbers with sum p+q ≤ 1. In addition, we prove concavity of the operator function
in its natural domain D
2(μ1,μ2), cf. Definition 3. 相似文献
16.
Thomas Bartsch Angela Pistoia Tobias Weth 《Communications in Mathematical Physics》2010,297(3):653-686
We prove the existence of equilibria of the N-vortex Hamiltonian in a bounded domain ${\Omega\subset\mathbb{R}^2}We prove the existence of equilibria of the N-vortex Hamiltonian in a bounded domain
W ì \mathbbR2{\Omega\subset\mathbb{R}^2} , which is not necessarily simply connected. On an arbitrary bounded domain we obtain new equilibria for N = 3 or N = 4. If Ω has an axial symmetry we obtain a symmetric equilibrium for each
N ? \mathbbN{N\in\mathbb{N}} . We also obtain new stream functions solving the sinh-Poisson equation -Dy = rsinhy{-\Delta\psi=\rho\sinh\psi} in Ω with Dirichlet boundary conditions for ρ > 0 small. The stream function yr{\psi_\rho} induces a stationary velocity field vr{v_\rho} solving the Euler equation in Ω. On an arbitrary bounded domain we obtain velocitiy fields having three or four counter-rotating
vortices. If Ω has an axial symmetry we obtain for each N a velocity field vr{v_\rho} that has a chain of N counter-rotating vortices, analogous to the Mallier-Maslowe row of counter-rotating vortices in the plane. Our methods also
yield new nodal solutions for other semilinear Dirichlet problems, in particular for the Lane-Emden-Fowler equation -Du=|u|p-1u{-\Delta u=|u|^{p-1}u} in Ω with p large. 相似文献
17.
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
18.
Let μ
0 be a probability measure on ℝ3 representing an initial velocity distribution for the spatially homogeneous Boltzmann equation for pseudo Maxwellian molecules.
As long as the initial energy is finite, the solution μ
t
will tend to a Maxwellian limit. We show here that if
, then instead, all of the mass “explodes to infinity” at a rate governed by the tail behavior of μ
0. Specifically, for L0, define
Let B
R
denote the centered ball of radius R. Then for every R,
The explicit rate is estimated in terms of the rate of divergence of η
L
. For example, if η
L
≥Const.L
s
, some s>0,
is bounded by a multiple of e
−[κ3s/(10+9s)]t
, where κ is the absolute value of the spectral gap in the linearized collision operator. Note that in this case, letting B
t
denote the ball of radius e
rt
for any r<κ
s/(10+9s), we still have
.
This result shows in particular that the necessary and sufficient condition for lim
t→∞
μ
t
to exist is that the initial data have finite energy. While the “explosion” of the mass towards infinity in the case of infinite
energy may seem to be intuitively clear, there seems not to have been any proof, even without the rate information that our
proof provides, apart from an analogous result, due to the authors, concerning the Kac equation. A class of infinite energy
eternal solutions of the Boltzmann equation have been studied recently by Bobylev and Cercignani. Our rate information is
shown here to provide a limit on the tails of such eternal solutions.
E. Carlen’s work is partially supported by U.S. National Science Foundation grant DMS 06-00037.
E. Gabetta’s and E. Regazzini’s work is partially supported by Cofin 2004 “Probleme matematici delle teorie cinetiche” (MIUR). 相似文献
19.
V. V. Anisovich L. G. Dakhno M. A. Matveev V. A. Nikonov A. V. Sarantsev 《Physics of Atomic Nuclei》2007,70(1):63-92
In the framework of the spectral integral equation, we consider the
states and their radiative transitions. We reconstruct the
interaction on the basis of data for the levels of the bottomonium states with J
PC = 0−+, 1−−, 0++, 1++, 2++ as well as the data for the radiative transitions γ (3S) → γχbJ(2P) and γ(2S) → γχbJ(1P) with J = 0, 1, 2. We calculate bottomonium levels with the radial quantum numbers n ≤ 6, their wave functions, and corresponding radiative transitions. The ratios Br[χbJ(2P) → γγ(2S)]/Br[χbJ(2P) → γγ(1S)] for J = 0, 1, 2 are found to be in agreement with data. We determine the
component of the photon wave function using the data for the e
+
e
− annihilation, e
+
e
− → γ(9460), γ(10 023), γ(10 036), γ(10 580), γ(10 865), γ(11 019), and predict partial widths of the two-photon decays ηb0 → γγ, χb0 → γγ, χb2 → γγ for the radial excitation states below the
threshold (n ≤ 3).
The text was submitted by the authors in English. 相似文献
20.
For the absolute value |C|=(C*C)1/2 and the Hilbert-Schmidt norm ∥C∥HS=(trC*C)1/2 of an operatorC, the following inequality is proved for any bounded linear operatorsA andB on a Hilbert space $$|| |A|---|B| ||_{HS} \leqq 2^{1/2} ||A - B||_{HS} $$ . The corresponding inequality for two normal state ? and ψ of a von Neumann algebraM is also proved in the following form: $$d(\varphi ,\psi ) \leqq ||\xi (\varphi ) - \xi (\psi )|| \leqq 2^{1/2} d(\varphi ,\psi )$$ . Here ξ(χ) denotes the unique vector representative of a state χ in a natural positive coneP ? forM, andd(?, ψ) denotes the Bures distance defined as the infimum (which is also the minimum) of the distance of vector representatives of ? and ψ. In particular, $$||\xi (\varphi _1 ) - \xi (\varphi _2 )|| \leqq 2^{1/2} ||\xi _1 - \xi _2 ||$$ for any vector representatives ξ j of ? j ,j=1, 2. 相似文献