scholarly journals Minimal Products of Coordinate and Momentum Uncertainties of High Orders: Significant and Weak High-Order Squeezing

Entropy ◽  
2020 ◽  
Vol 22 (9) ◽  
pp. 980
Author(s):  
Miguel Citeli de Freitas ◽  
Vitor Dantas Meireles ◽  
Viktor V. Dodonov
Keyword(s):  
Lower Bounds ◽  
Coherent States ◽  
High Order ◽  
Point Of View ◽  
Squeezed States ◽  
Mean Values ◽  
Fock States

We consider the problem of minimization of products of mean values of the high powers of operators x and p. From this point of view, we study several two-term superpositions of the Fock states, as well as three popular families of infinite superpositions: squeezed states, even/odd coherent states, and orthogonal even coherent states (or compass states). The new element is the analysis of products of the corresponding (co)variances and the related generalized (Robertson–Schrödinger) intelligent states (RSIS). In particular, we show that both Fock and pure Gaussian homogeneous states are RSIS for the fourth powers (but not for the sixth ones). We show that lower bounds of the high-order uncertainty products can be significantly below the vacuum values. In this connection, the concept of significant and weak high-order squeezing is introduced.

scholarly journals Non-Gaussianity of Four-Photon Superpositions of Fock States

2021 ◽  
Vol 3 (3) ◽  
pp. 350-365
Author(s):  
Miguel Citeli de Freitas ◽  
Viktor V. Dodonov
Keyword(s):  
Fourth Order ◽  
Effective Temperature ◽  
Coherent States ◽  
Squeezed States ◽  
Gaussian States ◽  
Fock States ◽  
The Past ◽  
Fidelity Measure ◽  
Non Gaussian ◽  
Thermal States

We study two families of four-photon superpositions of the Fock states: even vacuum squeezed states (EVSS) and orthogonal-even coherent states (OECS). These families are distinguished due to several properties: for certain values of parameters, they give the fourth-order uncertainty products close to the known minimal value (which is lower than for the Gaussian states); they have equal dimensionless values of the second- and fouth-order moments of the coordinate and momentum for all values of parameters; they possess zero covariances for all values of parameters. Since these states are obviously non-Gaussian, we consider them as good candidates to compare several different measures of non-Gaussianity proposed by different authors for the past fifteen years. The reference Gaussian states in all examples are thermal states dependent on a single parameter (an effective temperature or the coordinate variance). We analyze the measures based on the normalized Hilbert–Schmidt distance and the relative entropy (introduced by Genoni–Paris–Banaszek), the fidelity measure (Ghiu–Marian–Marian) and its logarithmic analog (Baek–Nha), as well as the Mandilara–Karpov–Cerf “Gaussianity parameter”. These measures are compared with the kurtosis of the coordinate probability density and with the non-Gaussian behavior of the Wigner function.

scholarly journals Non-Gaussianity of Four-Photon Superpositions of Fock States

2021 ◽  
Author(s):  
Viktor V. Dodonov ◽  
Miguel de Freitas Citeli
Keyword(s):  
Coherent States ◽  
Squeezed States ◽  
Fock States

We compare several different measures of non-Gaussianity for two families of four-photon superpositions of the Fock states: even vacuum squeezed states and orthogonal-even coherent states.

scholarly journals Semi-Classical Localisation Properties of Quantum Oscillators on a Noncommutative Configuration Space

2015 ◽  
Vol 22 (04) ◽  
pp. 1550021 ◽  
Author(s):  
Fabio Benatti ◽  
Laure Gouba
Keyword(s):  
Phase Space ◽  
Configuration Space ◽  
Classical Limit ◽  
Coherent States ◽  
Point Of View ◽  
Quantum Mechanical ◽  
Wigner Functions ◽  
Quantum Mechanical Oscillators ◽  
Mechanical Oscillators ◽  
Space Noncommutativity

When dealing with the classical limit of two quantum mechanical oscillators on a noncommutative configuration space, the limits corresponding to the removal of configuration-space noncommutativity and position-momentum noncommutativity do not commute. We address this behaviour from the point of view of the phase-space localisation properties of the Wigner functions of coherent states under the two limits.

scholarly journals The Environmental Effects of the April 2020 Wildfires and the Cs-137 Re-Suspension in the Chernobyl Exclusion Zone: A Multi-Hazard Threat

Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 467
Author(s):  
Rocío Baró ◽  
Christian Maurer ◽  
Jerome Brioude ◽  
Delia Arnold ◽  
Marcus Hirtl
Keyword(s):  
Air Quality ◽  
Nuclear Power ◽  
Transport Model ◽  
Atmospheric Transport ◽  
Point Of View ◽  
Plume Dispersion ◽  
Exclusion Zone ◽  
Fire Plume ◽  
Mean Values ◽  
The Impact

This paper demonstrates the environmental impacts of the wildfires occurring at the beginning of April 2020 in and around the highly contaminated Chernobyl Exclusion Zone (CEZ). Due to the critical fire location, concerns arose about secondary radioactive contamination potentially spreading over Europe. The impact of the fire was assessed through the evaluation of fire plume dispersion and re-suspension of the radionuclide Cs-137, whereas, to assess the smoke plume effect, a WRF-Chem simulation was performed and compared to Tropospheric Monitoring Instrument (TROPOMI) satellite columns. The results show agreement of the simulated black carbon and carbon monoxide plumes with the plumes as observed by TROPOMI, where pollutants were also transported to Belarus. From an air quality and health perspective, the wildfires caused extremely bad air quality over Kiev, where the WRF-Chem model simulated mean values of PM2.5 up to 300 µg/m3 (during the first fire outbreak) over CEZ. The re-suspension of Cs-137 was assessed by a Bayesian inverse modelling approach using FLEXPART as the atmospheric transport model and Ukraine observations, yielding a total release of 600 ± 200 GBq. The increase in both smoke and Cs-137 emissions was only well correlated on the 9 April, likely related to a shift of the focus area of the fires. From a radiological point of view even the highest Cs-137 values (average measured or modelled air concentrations and modelled deposition) at the measurement site closest to the Chernobyl Nuclear Power Plant, i.e., Kiev, posed no health risk.

SUSY coherent states and enhanced canonical quantizations for Pauli model

2021 ◽  
pp. 2150105
Author(s):  
Jean Vignon Hounguevou ◽  
Daniel Sabi Takou ◽  
Gabriel Y. H. Avossevou
Keyword(s):  
Quantum Mechanics ◽  
Quantum Theory ◽  
Coherent States ◽  
Differential Operators ◽  
Canonical Quantization ◽  
Point Of View ◽  
Supersymmetric Quantum Mechanics ◽  
Geometric Properties

In this paper, we study coherent states for a quantum Pauli model through supersymmetric quantum mechanics (SUSYQM) method. From the point of view of canonical quantization, the construction of these coherent states is based on the very important differential operators in SUSYQM call factorization operators. The connection between classical and quantum theory is given by using the geometric properties of these states.

scholarly journals Comparison of physical and qualitative traits of meat of two Polish conservative flocks of ducks

2004 ◽  
Vol 47 (4) ◽  
pp. 367-375 ◽  
Author(s):  
T. Kisiel ◽  
J. M. Książkiewicz
Keyword(s):  
Subcutaneous Fat ◽  
Biceps Femoris ◽  
Point Of View ◽  
Muscle Fibres ◽  
Mean Values ◽  
Qualitative Traits ◽  
Biceps Femoris Muscle ◽  
Leg Muscles ◽  
L Value ◽  
Femoris Muscle

Abstract. In two Polish conservative flocks of Miniduck (K2) and Pekin (P33), registered by FAO as domestic genetic resources (World Watch List, 2000) the mean values of physical (tissue components) and qualitative traits of meat (pH15, pH24, colour of meat) were determined. The experimental flocks showed significant variations in body weight at 7 weeks of age (1540 vs 2088 in drakes and 1395 vs 1986 g in ducks), in the proportion of breast and leg muscles and skin with subcutaneous fat in eviscerated carcass. K2 ducks are characterized by outstanding musculature of breast and P33 ducks by that of lower leg and by low fatness. pH15 values of breast and leg muscles in K2 and P33 birds were greater than pH24 of these muscles. In both flocks pH15 values of 6.09 to 6.33 and pH24 values of 5.90 to 6.05 in breast muscles were lower than in leg muscles (6.33 to 6.46 and 6.12 to 6.37, respectively). A significantly lower L* value (darker colour) of breast muscle was characteristic of K2 birds (43.7 in males and 40.5 in females) compared to P33 males and females. Furthermore, breast muscles of K2 drakes and ducks had significantly higher redness (a*) and yellowness values (b*) than P33. In pectoralis superficialis muscle of K2 and P33 females, a significantly lower diameter was found for white muscle fibres (αW) (30.0 to 30.5 μm) and for red muscle fibres (βR) (16.9 to 17.6 μm) than in biceps femoris muscle (αW from 48.3 to 54.2; βR from 36.0 to 37.1 μm). Muscle fibres of K2 compared to P33 ducks were characterized by significantly greater diameters of βR muscle fibre in pectoralis superficialis muscle, and by lower αW and βR fibre diameters in biceps femoris muscle. The experiment showed that meat of ducks from the conservative flocks studied is valuable from the consumer’s point of view.

Thermal Coherent States and Thermal Squeezed States

1991 ◽  
Vol 38 (12) ◽  
pp. 2339-2347 ◽  
Author(s):  
J. Oz-Vogt ◽  
A. Mann ◽  
M. Revzen
Keyword(s):  
Coherent States ◽  
Squeezed States

ANALISIS TERHADAP SOAL PENILAIAN AKHIR SEMESTER TINGKAT SD/MI DALAM PERSPEKTIF HIGH ORDER THINK SKILLS

2020 ◽  
Vol 12 (33) ◽  
Author(s):  
Yudha Andana Prawira ◽  
Titim Kurnia
Keyword(s):  
Critical Thinking ◽  
Critical Reflection ◽  
Descriptive Analysis ◽  
High Order ◽  
Point Of View ◽  
The Other ◽  
National Education ◽  
The One ◽  
High Level ◽  
High Level Thinking

The National Education World is currently trying to improve the ability of its students to think critically and creatively. One of these efforts has been pursued through evaluations that also lead to critical reflection. This research is a descriptive analysis of the final semester evaluation questions that are examined from the point of view of high-level thinking [HOTS]. The reference to the HOTS criteria is that the researcher refers to the opinions of King and his friends. From the manuscript data, the issues examined are samples from the Bandung area. The results of the analysis show that 10 out of 15 HOTS ranges proposed by King are already included in the scripts made by the teachers. On the one hand, it shows the teacher's creativity in compiling questions. On the other hand, all these questions do not refer to the HOTS criteria as planned. Therefore, there is a need to increase teachers' skills in compiling scripts as HOTS. This increase can be done through teacher training.Keywords: Evaluation, HOTS, critical thinking and creativity thingking

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