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

Disoriented Chiral Condensate and Charge-Neutral Particle Fluctuations in Heavy Ion Collisions

The posibility of large charge and isospin fluctuations in high-energy heavy ion-collisions is studied within the framework of the nonlinear $\sigma$-model with quark degrees of freedom. The multipion exchange potential between two quarks is derived. It is shown that the soft chiral pion bremsstralung leads to anomalously large fluctuations in the ratio of neutral to charged pions, predicted by the formation of a disoriented chiral condensate (DCC). The factorization property of the scattering amplitude in the impact parameter space of the leading two-nucleon system is used to study semiclassical production of pions in the central region. We show that the DCC-type fluctuations are suppressed if a large number of pions are produced in $\rho$-type clusters. Our conclusion is supported through the calculation of two pion correlation parameters as a function of the $\rho$-to-$\pi$ ratio.Comment: 20 pages, 2 figures, NAPP 2003 Conference,Dubrovnik. submitted to Fizika

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

Quantum Horizons and Space-Time Non-Commutativity

We study dynamics of a scalar field in the near-horizon region described by a static Klein-Gordon operator which is the Hamiltonian of the system. The explicite construction of a time operator near-horizon is given and its self-adjointness discussed.Comment: LaTex, 6 pages, no figures, Expanded version of a poster presented at 5 European Advanced Study Conference in Ancient Olympia, Greece, July 2004. to appear in a special issue of IJB

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 $D$ of the pion- multiplicity distribution is linearly related to the average multiplicity $$ : $D = A + B$, with the coefficient $A < 1$. The Hamiltonian of our model is expressed linearly in terms of the generators of the $SU(1,1)$ group.We also find the generating function for the pion field, which reduces to the generating function of the NB distribution limit $T \to 0$.Comment: 16 pages, no pictures, late

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 ~ $10^{-18}$ 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

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 $\sigma$-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 $E = mc^2$, obeying the quantum condition $E = h\nu$.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

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