New Physics and CP Violation in Singly Cabibbo Suppressed D Decays

We analyze various theoretical aspects of CP violation in singly Cabibbo suppressed (SCS) D-meson decays, such as $D \to K K,\pi \pi$. In particular, we explore the possibility that CP asymmetries will be measured close to the present level of experimental sensitivity of $O(10^{-2})$. Such measurements would signal new physics. We make the following points: (i) The mechanism at work in neutral D decays could be indirect or direct CP violation (or both). (ii) One can experimentally distinguish between these possibilities. (iii) If the dominant CP violation is indirect, then there are clear predictions for other modes. (iv) Tree-level direct CP violation in various known models is constrained to be much smaller than $10^{-2}$. (v) SCS decays, unlike Cabibbo favored or doubly Cabibbo suppressed decays, are sensitive to new contributions from QCD penguin operators and especially from chromomagnetic dipole operators. This point is illustrated with supersymmetric gluino-squark loops, which can yield direct CP violating effects of $O(10^{-2})$.Comment: 36 pages, 5 figure

Simulation of the Pneumatic System of a Seed Drill with a Vertical Flow Direction

The purpose of the work is to reveal the influence of conical directing agents on the speed and trajectory of particles movement in the vertical pneumatic conduit of the sowing machine and to establish their rational parameters. With the help of numerical modeling the particle flight trajectories in the air flow were obtained. The carried out researches have shown expediency of application of the conical directing agent, allowing to take away a longitudinal stream of particles from walls of a pneumatic conduit and to centre their trajectories of movement along an axis of a pneumatic conduit. Particles are focused to the center of the distributor when the distributor covers the area of pneumatic conduit cross-section close to 25%

Learning Representations that Support Extrapolation

Extrapolation -- the ability to make inferences that go beyond the scope of one's experiences -- is a hallmark of human intelligence. By contrast, the generalization exhibited by contemporary neural network algorithms is largely limited to interpolation between data points in their training corpora. In this paper, we consider the challenge of learning representations that support extrapolation. We introduce a novel visual analogy benchmark that allows the graded evaluation of extrapolation as a function of distance from the convex domain defined by the training data. We also introduce a simple technique, temporal context normalization, that encourages representations that emphasize the relations between objects. We find that this technique enables a significant improvement in the ability to extrapolate, considerably outperforming a number of competitive techniques.Comment: ICML 202

Observation of discrete vortex solitons in optically-induced photonic lattices

We report on the frst experimental observation of discrete vortex solitons in two-dimensional optically-induced photonic lattices. We demonstrate strong stabilization of an optical vortex by the lattice in a self-focusing nonlinear medium and study the generation of the discrete vortices from a broad class of singular beams.Comment: 4pages, 5 colour figures. to appear in PR

Macroscopic model of formation of the domain of multiple filamentation in glass and water

The results of natural experiments of the propagation of powerful femtosecond laser radiation in glass and water

Laser-ion acceleration through controlled surface contamination

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98750/1/PhysPlasmas_18_040702.pd

Green Energy for Belt and Road Initiative: Economic Aspects Today and in the Future

The Belt and Road Initiative (BRI) is a comprehensive megaproject, which includes numerous projects in the sphere of green energy. The effectiveness of these projects is often doubted. The article reveals the main mechanisms of green energy projects' influence on the economy and through the research of 8 BRI countries demonstrates the method of green energy projects efficiency estimation. China is considered to be the main driver for green energy proliferation in Asia, receiving economic benefits through its policy. The authors prove this to be right, but the effects for PRC differ in short and long-run periods. The main findings of the paper are that the BRI green energy dissemination is just the first step to building a tightly interconnected Asian energy infrastructure, and that the BRI least developed countries have less positive long-run effects from green energy investment, while in short-term they get a boost for their economies. Keywords: BRI, green energy, energy, Asian region, China, JEL Classifications: F21; K32; O44 DOI: https://doi.org/10.32479/ijeep.804

Multiple filamentation of laser beams with different diameters in the air at a 100-meter path

Results of experiments on controlling the position and length of the filamentation zone of femtosecond laser pulses in atmospheric path length 110 m using different initial spatial focusing and defocusing. The obtained distribution of filaments along the filamentation zone, measured dependence the length of the filamentation zone of the numerical aperture of the beam, its initial radius and pulse power

Multiple filamentation of laser beams with different diameters in the air at a 150-meter path

Results of experiments on controlling the position and length of the filamentation zone of femtosecond laser pulses in atmospheric path length 150 m using different initial spatial focusing and defocusing. The obtained distribution of filaments along the filamentation zone, measured dependence the length of the filamentation zone of the numerical aperture of the beam, its initial radius and pulse power

Filamentation of terawatt laser pulses along hundred-meter atmospheric paths

Results of the experimental study of filamentation of terawatt femtosecond pulses of a Ti:Sapphire laser along an atmospheric path 106 m long using different spatial focusing and pulse power are presented. The control of filamentation region position and length by means of changing the initial laser beam focusing is shown to be highly effective. Dependencies are derived of filamentation region position and length on the initial degree of focusing, pulse power, and the number of filaments along the filamentation region. The obtained data on the filamentation region length and the number of filaments are compared with the results of our previous experiments and data from other authors