1,552 research outputs found
Need for the intensity-dependent pion-nucleon coupling in multipion production processes
We give reasons in support of the use of an effective intensity-dependent
pion-nucleon coupling Hamiltonian for describing the properties of the pion
multiplicity distribution and the corresponding factorial moments within the
thermal-density matrix approach.We explain the appearance of the
negative-binomial (NB) distribution for pions and the well-known empi- rical
relation of Wroblewski.Our model Hamiltonian is written as a linear combination
of the generators of the SU(1,1) group.We find the generating function for the
pion multiplicity distribution at finite temperature T and discuss the
properties of the second-order factorial moment.Also, we show that an
intensity-dependent pion-nucleon coupling generates the squeezed states of the
pion field. At T=0, these squeezed states become an inherent property of the NB
distribution.Comment: 18 pages, no figures, late
Existence of Time Operator for a Singular Harmonic Oscillator
The time operator for a quantum singular oscillator of the
Calogero-Sutherland type is constructed in terms of the generators of the
SU(1,1) group. In the space spanned by the eigenstates of the Hamiltonian, the
time operator is not self-adjoint. We show, that the time-energy uncertainty
relation can be given the meaning within the Barut-Girardello coherent states
defined for the singular oscillator.We have also shown the relationship with
the time-of-arrival operator of Aharonov and Bohm.Comment: 7 pages, no figures, LaTex, submitted to Concepts of Physic
Qubit metrology for building a fault-tolerant quantum computer
Recent progress in quantum information has led to the start of several large
national and industrial efforts to build a quantum computer. Researchers are
now working to overcome many scientific and technological challenges. The
program's biggest obstacle, a potential showstopper for the entire effort, is
the need for high-fidelity qubit operations in a scalable architecture. This
challenge arises from the fundamental fragility of quantum information, which
can only be overcome with quantum error correction. In a fault-tolerant quantum
computer the qubits and their logic interactions must have errors below a
threshold: scaling up with more and more qubits then brings the net error
probability down to appropriate levels ~ needed for running complex
algorithms. Reducing error requires solving problems in physics, control,
materials and fabrication, which differ for every implementation. I explain
here the common key driver for continued improvement - the metrology of qubit
errors.Comment: 4 pages, 2 figure
Intensity-dependent pion-nucleon coupling in multipion production processes
We propose an intensity-dependent pion-nucleon coupling Hamiltonian within a
unitary multiparticle-production model of the Auerbach-
Avin-Blankenbecler-Sugar (AABS) type in which the pion field is represented by
the thermal-density matrix.Using this Hamiltonian, we explain the appearance of
the negative-binomial (NB) distribution for pions and the well-known empirical
relation, the so-called Wr\' oblewski relation, in which the dispersion of
the pion- multiplicity distribution is linearly related to the average
multiplicity : , with the coefficient . The
Hamiltonian of our model is expressed linearly in terms of the generators of
the group.We also find the generating function for the pion field,
which reduces to the generating function of the NB distribution limit .Comment: 16 pages, no pictures, late
Disoriented Chiral Condensates and Anomalous Production of Pions
The leading-particle effect and the factorization property of the scattering
amplitude in the impact parameter space are used to study semiclassical
production of pions in the central region. The mechanism is related to the
isospin-uniform solution of the nonlinear -model coupled to quark
degrees of freedom. The multipion exchange potential between two quarks is
derived. It is shown thatthe soft chiral pion bremsstralung also leads to
anomalously large fluctuations in the ratio of neutral to charged pions. We
show that only direct production ofpions in the form of an isoscalar coherent
pulse without isovector pairs can lead to large neutral-charged fluctuations.Comment: Latex, 22 pages, 2 figure
On the Gravitational Energy Shift for matter waves
The gravitational energy shift for photons is extended to all mass-equivalent
energies , obeying the quantum condition .On an example of
a relativistic binary system, it was shown that the gravitational energy shift
would imply,in contrast to Newtonian gravity, the gravitational attraction
between full mass-equivalent energies. The corresponding space-time metric
becomes exponential. A good agreement was found with all results of weak field
tests of General relativity. The strong field effects in a binary system can be
easily studied. A long standing problems of Pioneer and other flyby anomalies
were also discussed in connection with the violation of total energy
conservation. It was shown that relatively small energy non-conservation during
the change of the orbit type could explain these persistent anomalies.Comment: 7 page
Peningkatan Kreativitas Anak Melalui Melukis Menggunakan Sikat Gigi Taman Kanak-kanak Padang
Kemampuan kreativitas anak masih rendah karena guru tidak menggunakan media yang bervariasi, sehingga anak menjadi bosan. Tujuan penelitian ini meningkatkan kreativitas anak melalui melukis menggunakan sikat gigi di Taman Kanak-kanak Warrahmah. Data kemampuan kreativitas dalam pembelajaran diperoleh dari lembar observasi yang dianalisis dengan teknik persentase dari siklus I dan siklus II. Berdasarkan hasil tindakan yang telah dilakukan telah terjadinya peningkatan kreativitas anak dengan melukis menggunakan sikat gigi. Sehingga dapat disimpulkan dengan melukis menggunakan sikat gigi dapat meningkatkan kreativitas anak di Taman Kanak-kanak Warrahmah Padang
Intensity-dependent pion-nucleon coupling in multipion production processes
We propose an intensity-dependent pion-nucleon coupling Hamiltonian within a unitary multiparticle-production model of the Auerbach- Avin-Blankenbecler-Sugar (AABS) type in which the pion field is represented by the thermal-density matrix.Using this Hamiltonian, we explain the appearance of the negative-binomial (NB) distribution for pions and the well-known empirical relation, the so-called Wr\' oblewski relation, in which the dispersion of the pion- multiplicity distribution is linearly related to the average multiplicity : , with the coefficient . The Hamiltonian of our model is expressed linearly in terms of the generators of the group.We also find the generating function for the pion field, which reduces to the generating function of the NB distribution limit
Isospin correlations in high-energy heavy-ion collisions
We study the posibility of large isospin fluctuations in high-energy heavy-ion collisions by assuming that pions are produced semiclassically both directly and in pairs through the isovector channel. The leading-particle effect and the factorization property of the scattering amplitude in the impact parameter space are used to define the classical pion field. In terms of the joint probability function P_{II_{3}}(n_{0},n_{ \_}) for producing n_{0} neutral and n_{ \_} negative pions from a definite isospin state II_{3} of the incoming leading-particle system we calculate the two pion correlation parameters f_{2,n_{ \_}}^{0} and the average number of neutral pions ( \langle n_{0} \rangle_{n_{ \_}}) as a function of negative pions (n_{ \_}) produced. We show that only direct production of pions without isovector pairs leads to large isospin fluctuations
Is there chaos in the electron microscope?
High-temperature superconductor has been
investigated by the high-resolution electron microscope (HREM) and the
photodensitometric technique in order to resolve the sub-atomic shifts in the
modulated structure. This investigation has shown that the background noise is
pronounced, indicating some kind of ordering in certain crystallographic
directions. We have found that the "mapping" of the charge densities by the
inverse Fourier transform of the diffracted electron image and the connections
to the crystal structure can be easily established in the case of elastically,
as well as the inelastically scattered electrons. The order of the details in
so obtained "inelastic" electron "micrographs", as well as the dependence of
the structure of the EM image on the initial conditions of the inverse Fourier
transform, leads to the conclusion that there is an order emerging from the
diffuse scattered electron diffraction patterns. Data sets from digitalized
densitograms are analysed by the Rescaled range (R/S) method in order to study
fractal and long-range correlation properties of the inelastic scattered
electrons in the "noise" region between Bragg reflections. The results of the
R/S analysis showed that the value of the Hurst exponent was H 0.5,
indicating that the "ordering" of the noise in the Inverse (Fourier) space was
much more pronounced at longer distances (about 440 atom spacings), then for
shorter distances of about 55 atom spacings.Comment: 13 pages, LaTeX, 8 jpg figures, submitted to Chao
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