scholarly journals Scalar-isoscalar states, gravitational form factors, and dimension-2 condensates in a large-N[sub c] Regge approach

2011 ◽  
Author(s):  
Enrique Ruiz Arriola ◽  
Wojciech Broniowski
Keyword(s):  
Form Factors ◽  
Large N ◽  
Dimension 2 ◽  
Regge Approach

scholarly journals Entanglement cost of generalised measurements

2003 ◽  
Vol 3 (5) ◽  
pp. 405-422
Author(s):  
R. Jozsa ◽  
M. Koashi ◽  
N. Linden ◽  
S. Popescu ◽  
S. Presnell ◽  
...  
Keyword(s):  
Quantum Measurements ◽  
Great Circle ◽  
Bloch Sphere ◽  
Numerical Techniques ◽  
Bipartite Entanglement ◽  
Von Neumann ◽  
Tensor Product Space ◽  
Large N ◽  
Dimension 2 ◽  
The Cost

Bipartite entanglement is one of the fundamental quantifiable resources of quantum information theory. We propose a new application of this resource to the theory of quantum measurements. According to Naimark's theorem any rank 1 generalised measurement (POVM) M may be represented as a von Neumann measurement in an extended (tensor product) space of the system plus ancilla. By considering a suitable average of the entanglements of these measurement directions and minimising over all Naimark extensions, we define a notion of entanglement cost E_{\min}(M) of M. We give a constructive means of characterising all Naimark extensions of a given POVM. We identify various classes of POVMs with zero and non-zero cost and explicitly characterise all POVMs in 2 dimensions having zero cost. We prove a constant upper bound on the entanglement cost of any POVM in any dimension. Hence the asymptotic entanglement cost (i.e. the large n limit of the cost of n applications of M, divided by n) is zero for all POVMs. The trine measurement is defined by three rank 1 elements, with directions symmetrically placed around a great circle on the Bloch sphere. We give an analytic expression for its entanglement cost. Defining a normalised cost of any $d$-dimensional POVM by E_{\min} (M)/\log_2 d, we show (using a combination of analytic and numerical techniques) that the trine measurement is more costly than any other POVM with d>2, or with d=2 and ancilla dimension 2. This strongly suggests that the trine measurement is the most costly of all POVMs.

scholarly journals TRANSVERSE CHARGE AND MAGNETIZATION DENSITIES IN THE NUCLEON'S CHIRAL PERIPHERY

2014 ◽  
Vol 25 ◽  
pp. 1460036 ◽  
Author(s):  
C. GRANADOS ◽  
C. WEISS
Keyword(s):  
Form Factors ◽  
High Energy ◽  
Effective Field ◽  
Light Front ◽  
Chiral Effective Field Theory ◽  
Independent Manner ◽  
Generalized Parton Distributions ◽  
Large N ◽  
Mechanical Interpretation ◽  
High Energy Scattering

In the light–front description of nucleon structure the electromagnetic form factors are expressed in terms of frame–independent transverse densities of charge and magnetization. Recent work has studied the transverse densities at peripheral distances [Formula: see text], where they are governed by universal chiral dynamics and can be computed in a model–independent manner. Of particular interest is the comparison of the peripheral charge and magnetization densities. We summarize (a) their interpretation as spin–independent and –dependent current matrix elements; (b) the leading–order chiral effective field theory results; (c) their mechanical interpretation in the light–front formulation; (d) the large–Nc limit of QCD and the role of Δ intermediate states; (e) the connection with generalized parton distributions and peripheral high–energy scattering processes.

scholarly journals Electromagnetic Form Factors of Hadrons in Dual-Large N[sub c] QCD

2011 ◽  
Author(s):  
C. A. Dominguez ◽  
Alejandro Ayala ◽  
Guillermo Contreras ◽  
Ildefonso Leon ◽  
Pedro Podesta
Keyword(s):  
Form Factors ◽  
Electromagnetic Form Factors ◽  
Large N

SPREADING OF N DIFFUSING SPECIES WITH DEATH AND BIRTH FEATURES

Fractals ◽  
1996 ◽  
Vol 04 (02) ◽  
pp. 161-168 ◽  
Author(s):  
S. HAVLIN ◽  
A. BUNDE ◽  
H. LARRALDE ◽  
Y. LEREAH ◽  
M. MEYER ◽  
...  
Keyword(s):  
Analytical Solution ◽  
Smooth Surface ◽  
Center Of Mass ◽  
Direct Measure ◽  
Dimensional Lattice ◽  
Random Walker ◽  
Random Walkers ◽  
Large N ◽  
Dimension 2 ◽  
The Mean

The number of distinct sites visited by a random walker after t steps is of great interest, as it provides a direct measure of the territory covered by a diffusing particle. We review the analytical solution to the problem of calculating SN(t), the mean number of distinct sites visited by N random walkers on a d-dimensional lattice, for d=1, 2, 3 in the limit of large N. There are three distinct time regimes for SN(t). A remarkable transition, for dimension ≥2, in the geometry of the set of visited sites is found. This set initially grows as a disk with a relatively smooth surface until it reaches a certain size, after which the surface becomes increasingly rough. We also review the results for a model for migration and spreading of populations and diseases. The model is based on N diffusing species, where each species has a probability α- of dying (or recovery from a disease) and a probability α+ to give birth (or to infect another species). It is found analytically that when α+ ≈ α- ≠ 0, after a crossover time t× ~ N/2α-, the territory covered by the population is localized around its center of mass while the center of mass diffuses regularly. When α+ > α-, the localization breaks down after a second crossover time and the species diffuse and spread around their center of mass. These results may explain the phenomena of migration and spreading of diseases and population appearing in nature.

CHIRAL SYMMETRY AND HOLOGRAPHIC MODELS OF THE BARYON: TESTING HOLOGRAPHIC MODELS OF THE BARYON WITH MODEL-INDEPENDENT RELATIONS

2010 ◽  
Vol 25 (02n03) ◽  
pp. 464-469
Author(s):  
THOMAS D. COHEN
Keyword(s):  
Form Factors ◽  
Skyrme Model ◽  
Holographic Model ◽  
Top Down ◽  
Long Distance ◽  
Scale Separation ◽  
Chiral Soliton ◽  
Large N ◽  
Model Independent ◽  
Distance Behavior

A model-independent relation for the long-distance behavior of baryon form factors in the large Nc and chiral limits is introduced and used to probe the consistency of various models of the baryon including recently proposed holographic models. This relation is satisfied by the Skyrme model and all other 4D semiclassical chiral soliton models. The "bottom-up" Pomarol-Wulzer holographic model which treats baryons as 5D Skyrmions also satisfies the relation. However, the "top down" holographic model treating baryons as instantons in the Sakai-Sugimoto model fails to satisfy the relation. This failure can ultimately be traced to the imposition of a scale separation in the model between the curvature scale and the KK scale; such a scale separation has no counterpart in QCD.

Kl4 Decays

2001 ◽  
Vol 16 (supp01a) ◽  
pp. 172-174
Author(s):  
Bing An Li
Keyword(s):  
Chiral Limit ◽  
Axial Vector ◽  
Form Factors ◽  
Vector Current ◽  
Decay Rates ◽  
Adjustable Parameter ◽  
Axial Vector Current ◽  
Effective Theory ◽  
Decay Modes ◽  
Large N

An effective theory of large NC QCD of mesons has been used to study six Kl4 decay modes. PCAC is satisfied. A relationship between three form factors of axial-vector current has been found. ρ → ππ plays important role. the decay rates are calculated in the chiral limit. There is no adjustable parameter.

$K_{l_4}$ DECAY ANALYSIS IN A PARAMETER-FREE RELATIVISTIC MODEL

1992 ◽  
Vol 07 (24) ◽  
pp. 2223-2227
Author(s):  
R. RAMANATHAN
Keyword(s):  
Form Factors ◽  
Relativistic Model ◽  
Large N ◽  
Hadron Mass ◽  
Free Model ◽  
Free Parameters ◽  
Experimental Values ◽  
Almost All ◽  
Best Fit ◽  
Good Agreement

The dimensionless form factors fs(0), g(0), h(0) and λ which account for almost all the microscopic details of the [Formula: see text] decay are computed in an integrated QCD oriented Bethe-Salpeter framework, where all the free parameters involved in the formalism are fixed by the best fit with the Hadron mass spectroscopy, so that for the present evaluation we have a parameter-free model. The values of the form factors so obtained are in good agreement with the experimental values and the agreement is comparable with the recent similar calculations using large-Nc limits in chiral QCD theory.

scholarly journals FORM FACTORS OF PION AND KAON

2001 ◽  
Vol 16 (supp01a) ◽  
pp. 175-177
Author(s):  
JUN GAO ◽  
Bing An Li
Keyword(s):  
Vector Meson ◽  
Form Factors ◽  
Adjustable Parameter ◽  
Chiral Theory ◽  
Large N ◽  
Intrinsic Form

The form factors of pion and kaon are studied by an effective chiral theory of large NC QCD. Besides the vector meson poles an additional intrinsic form factors are found. Theory agrees well with data in both time-like and space-like regions. There is no adjustable parameter.

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