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1.
There are aspects of privacy theory that are analogous to quantum theory. In particular one can define distillable key and
key cost in parallel to distillable entanglement and entanglement cost. We present here classical privacy theory as a particular
case of information theory with adversaries, where similar general laws hold as in entanglement theory. We place the result
of Renner and Wolf—that intrinsic information is lower bound for key cost—into this general formalism. Then we show that the
question of whether intrinsic information is equal to key cost is equivalent to the question of whether Alice and Bob can
create a distribution product with Eve using IM bits of secret key. We also propose a natural analogue of relative entropy of entanglement in privacy theory and show that
it is equal to the intrinsic information. We also provide a formula analogous to the entanglement of formation for classical
distributions.
It is our pleasure to dedicate this paper to Asher Peres on the occasion of his seventieth birthday. 相似文献
2.
The weak radiative decay Λ
b
→Λγ is studied in the heavy quark effective theory treatings-quark as heavy. This rare decay is induced by the short distance electromagnetic penguins. Including corrections of the order
of (1/m
Q), we obtain the transition matrix element and the corresponding decay width. The Isgur-Wise function is evaluated in the
largeN
c limit and the branching ratio obtained is 1.48×10−5. 相似文献
3.
Final state interaction effects inpp→ pΛK
+ andpd →3Heη reactions are explored near threshold to study the sensitivity of the cross-sections to thepΛ potential and theηN scattering matrix. The final state scattering wave functions between Λ andp andη and3He are described rigorously. The Λ production is described by the exchange of one pion and aK-meson between two protons in the incident channel. Theη production is described by a two-step model, where in the first step a pion is produced. This pion then produces anη by interacting with another nucleon 相似文献
4.
Polarization correlation in the two-photon decay of atomic hydrogen: nonlocality versus entanglement
T. Radtke A. Surzhykov S. Fritzsche 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,49(1):7-12
From the work by Perrie et al. [Phys. Rev. Lett. 54, 1790 (1985)], photon pairs from the 2s
1/2 → 1s
1/2 (two-photon) decay of atomic hydrogen are known to be quantum mechanically correlated. In these experiments, the polarization
states of the photons emitted in back-to-back geometry were shown to violate the Bell inequality as a qualitative sign of
nonlocality and entanglement. In the present contribution, we analyze how these nonlocal quantum correlations, as given by
the violation of the Bell inequality, differ from the concurrence as a true entanglement measure. Results are shown for both
quantifiers in dependence of the decay geometry and the initial polarization of the atoms for the 2s
1/2 → 1s
1/2 and 3d
5/2 → 1s
1/2 two-photon decay of atomic hydrogen. These results display the difference between nonlocality and entanglement and, hence,
may stimulate further experiments on nonlocal quantum correlations in atomic systems. 相似文献
5.
Cross-sections, beam asymmetries, and recoil polarisations for the reactions γp → K
+Λ;γp → K
+Σ0, and γp → K
0Σ+ have been measured by the SAPHIR, CLAS, and LEPS Collaborations with high statistics and good angular coverage for centre-of-mass
energies between 1.6 and 2.3 GeV. The combined analysis of these data with data from π and η photoproduction reveals evidence
for new baryon resonances in this energy region. A new P11 state with mass 1840 MeV and width 140 MeV was observed contributing to most of the fitted reactions. The data demand the
presence of two D13 states at 1875 and, optimistically, at 2170 MeV. 相似文献
6.
We report on a study of the proton induced hyperon production reactions. We discuss the theoretical efforts made towards understanding
the existing data and the uncertainties involved in the calculations. Our recent calculations of the missing mass spectra
for the pp → K
+ Λp reaction which involve a proper coupled channel treatment of the final state Λp interaction are presented. Significant differences in the results using different models of the hyperon-nucleon interaction
are found. 相似文献
7.
Xiao-Gang He Xue-Qian Li Xiang Liu Xiao-Qiang Zeng 《The European Physical Journal C - Particles and Fields》2007,51(4):883-889
A new baryonic state Λc(2940)+ has recently been discovered by the Babar collaboration in the D0p channel. Later Belle collaboration also observed this state in the Σc(2455)0,++π±→Λc
+π+π- channel. The mass of Λc(2940)+ is just a few MeV below the sum of D*0 and p masses suggesting a possibility that this state may be a D*0p molecular state. In this paper we study whether such a molecular state can be consistent with data. We find that the molecular
structure can explain data and that if Λc(2940)+ is a D*0p molecular state it is likely a 1/2- state. Several other decays modes are also suggested to further test the molecular structure of Λc
+(2940).
PACS 13.30.Eg; 14.20.Lg; 12.39.Pn 相似文献
8.
The physics realization of a ququadrit quantum computation with cooled trapped 138Ba+ ions in a Paul trap is investigated. The ground state level 62 S1/2(m = −1/2) and three metastable levels: 52 D3/2(m = −1/2), 52 D5/2(m = −1/2), and 52 D5/2(m = 1/2), of the fine-structure of the 138Ba+ ion, are used to store the quantum information of ququadrits. The use of coherent manipulation of populations in single ququadrit,
being a four-dimensional Hilbert space, produces a discrete Fourier transform and the manipulation of the first red band transitions
with the introduction of an ancillary quantum channel between two ququadrits generates a conditional phase gate. The combination
of the both above results in a universal two-ququadrit gate, called XOR(4) gate corresponding to the controlled-NOT gate operation in qubit systems. The implementation of quantum Fourier transform
for n ququadrits is performed by means of the conditional phase-shift gate. The feasibility of physical realization of ququadrit
quantum computation with cooled-trapped 138Ba+ ions is detailed analyzed and described, and the theoretical detection method of logical states is given. Higher entanglement
between ququadrits than qutrits or qubits and more security of ququadrit quantum cryptography than qutrit's or qutrit's will
lead to more extensive applications ququadrits in quantum information fields. In particular, it is pointed out that this scheme
should be the highest dimensional quantum computation in cooled-trapped ions, the entanglement between ququadrits should be
the highest dimensional entanglement in it, and the ququadrit quantum cryptography should be the most secure cryptography
protocol in it. 相似文献
9.
Variational Monte Carlo calculations of the ground state separation energiesB
Λ of thes-shell hypernuclei and also of
Λ
9
Be have been made for an Urbana-type central space-exchange ΛN potential consistent with Λp scattering, and also including three-body ΛNN forces. Thes-shell hypernuclei are treated asA-body systems (A = baryon number), and
Λ
9
Be is analysed as a partially nine-body problem in the Λ — 2α model. The reduction ofB
Λ due to the space-exchange ΛN potential has been calculated for thes-shell hypernuclei for a range of interactions: both ΛN and ΛN + ΛNN forces. ForA = 3,4,5 the exchange energy is approximately, 0.04, 0.15 and 0.50 MeV, respectively. For
Λ
9
Be a much more limited study gives ≅ 1.3 MeV. These values are much larger than that for ‘soft’ ΛN +NN potentials when the correlations are weak.
Preliminary results were presented at the DAE Symp. on ‘Nuclear Physics’ Vol. 32B (1989). 相似文献
10.
Mahmood Mian 《Pramana》1993,41(2):145-149
The binding energy of the double hypernucleus
ΛΛ
6
is calculated in α + 2Λ cluster model using the method of translation invariant basis TIMO. As regards the required interaction
potentials we use a density dependent effective ΛN force and a gaussian form for ΛΛ potential. With these interactions a very reasonable value ofB
ΛΛ is obtained if the oscillator states up to the excitation quantum numberN=12 are taken into account in the expansion of wavefunction of the hypernucleus. This value ofN is much smaller than that obtained in an earlier study. This lowering inN value is attributed to a much better choice of ΛN potential used in the present study. 相似文献
11.
12.
Bijan K Bagchi 《Pramana》1981,17(5):405-414
We consider the effects ofη−π mixing on the violation of the |ΔI|=1/2 rule in |ΔS|=1 weak transitions. The processes considered are theK→2π,K→3π, Λ, Ξ and Λ hyperon decays. 相似文献
13.
Gan Gao 《International Journal of Theoretical Physics》2010,49(8):1870-1877
By swapping the entanglement of χ-type state, we propose a quantum key distribution protocol, in which only Alice needs to prepare χ-type states and transmit a particle sequence. Both Alice and Bob need to perform χ-type state measurements. 相似文献
14.
Chien-Wen Hwang 《The European Physical Journal C - Particles and Fields》2007,50(4):793-799
The strong decays of the heavy baryons Σ(*)
Q→ΛQπ are studied by combining the chiral dynamics and the MIT bag model. In the charm sector, we calculate the decay widths Γ(Σ(*)
c→Λcπ) and compare these with the experimental data and other theoretical estimations. In addition, we also predict the strong
decay widths Γ(Σ(*)
b→Λbπ). 相似文献
15.
A. K. Pal I. Bose 《The European Physical Journal B - Condensed Matter and Complex Systems》2012,85(1):36
The transverse Ising Model (TIM) in one dimension is the simplest model which exhibits a quantum phase transition (QPT). Quantities
related to quantum information theoretic measures like entanglement, quantum discord (QD) and fidelity are known to provide
signatures of QPTs. The issue is less well explored when the quantum system is subjected to decoherence due to its interaction,
represented by a quantum channel, with an environment. In this paper we study the dynamics of the mutual information I(ρ
AB
), the classical correlations C(ρ
AB
) and the quantum correlations Q(ρ
AB
), as measured by the QD, in a two-qubit state the density matrix of which is the reduced density matrix obtained from the
ground state of the TIM in 1d. The time evolution brought about by system-environment interactions is assumed to be Markovian
in nature and the quantum channels considered are amplitude damping, bit-flip, phase-flip and bit-phase-flip. Each quantum
channel is shown to be distinguished by a specific type of dynamics. In the case of the phase-flip channel, there is a finite
time interval in which the quantum correlations are larger in magnitude than the classical correlations. For this channel
as well as the bit-phase-flip channel, appropriate quantities associated with the dynamics of the correlations can be derived
which signal the occurrence of a QPT. 相似文献
16.
The fluorescent transitions5
D
0.1 →7
F
J (J=0−4) of the europium ion in the Tb1.8Eu0.2 (MoO4)3 single crystal were recorded at 300 and 20 K. The forbidden and the hypersensitive transitions were observed in this system.
The intensity ratio between5
D
0 →7
F
1 and5
D
0 →7
F
2 which is 1:5 is discussed in the light of covalency between the Eu3+ ion and MoO4 tetrahedra. 相似文献
17.
18.
A simple method has been applied to solve the approximate gluon evolution equation for small-x at fixedρ(≡√ln(x
0/x)/ln[ln(Q
2/Λ2)/ln(Q
0
2
/Λ2)]. Numerical comparison is made with the predictions from ‘double asymptotic scaling’ and fit. Better agreement is found
between our solution and fit nearρ=1. The solution gives approximate double scaling in this region having ‘hard’ pomeron with small contamination. 相似文献
19.
O. Bartholomy R. Bogendörfer V. Credé I. Fabry A. V. Anisovich G. Anton R. Bantes Y. A. Beloglazov R. Castelijns A. Ehmanns J. Ernst H. Flemming A. Fösel M. Fuchs Ch. Funke R. Gothe A. B. Gridnev E. Gutz S. Höffgen I. Horn J. Hößl J. Junkersfeld H. Kalinowsky F. Klein E. Klempt H. Koch M. Konrad B. Kopf B. Krusche J. Langheinrich H. Löhner I. V. Lopatin J. Lotz H. Matthäy D. Menze J. Messchendorp V. A. Nikonov D. V. Novinski M. Ostrick H. van Pee A. K. Radkov A. V. Sarantsev S. Schadmand C. Schmidt H. Schmieden B. Schoch G. Suft V. V. Sumachev T. Szczepanek U. Thoma D. Walther Ch. Weinheimer 《The European Physical Journal A - Hadrons and Nuclei》2007,33(2):133-146
Photoproduction of η -mesons was studied with the Crystal-Barrel detector at ELSA for photon energies in the range from 0.75
to 3GeV. Total and differential cross-sections are presented. The η mesons are detected in two decay modes, in η → 2γ and
in η → 3π0 → 6γ . The cross-sections vary slowly as functions of energy and η production angle suggesting that only few resonances make
significant contributions to the cross-section. For photon energies above 1.5GeV, the differential cross-sections show a strong
forward peak due to meson exchanges in the t channel. A comparison of the η -photoproduction cross-sections with SAID and MAID as well as with a partial-wave analysis
performed on our data in combination with other data sets shows good agreement. The Bonn-Gatchina partial-wave analysis suggests
that the largest contribution to η photoproduction for energies below 3GeV proceeds via three resonances, the well-known N(1535)S
11 , via N(1720)P
13 , and a newly suggested N(2070)D
15 . 相似文献
20.
A. Lleres O. Bartalini V. Bellini J. P. Bocquet P. Calvat M. Capogni L. Casano M. Castoldi A. D'Angelo J. -P. Didelez R. Di Salvo A. Fantini C. Gaulard G. Gervino F. Ghio B. Girolami A. Giusa M. Guidal E. Hourany V. Kouznetsov R. Kunne A. Lapik P. Levi Sandri D. Moricciani A. N. Mushkarenkov V. Nedorezov L. Nicoletti C. Perrin C. Randieri D. Rebreyend F. Renard N. Rudnev T. Russew G. Russo C. Schaerf M. -L. Sperduto M. -C. Sutera A. Turinge 《The European Physical Journal A - Hadrons and Nuclei》2007,31(1):79-93
Beam asymmetries and hyperon recoil polarizations for the reactions γp → K
+Λ and γp → K
+Σ0 have been measured from the threshold production to 1500MeV with the GRAAL facility located at the ESRF in Grenoble. These
results complement the database for the beam asymmetry, covering for the first time the production threshold region. Recent
theoretical analyses are presented for which the beam asymmetry data bring interesting new information and allow to better
determine some resonance parameters. Most importantly, these results strengthen the need of a new D13 state around 1900MeV. 相似文献