scholarly journals Information Contained in Molecular Motion

Entropy ◽  
2019 ◽  
Vol 21 (11) ◽  
pp. 1052 ◽  
Author(s):  
J Gerhard Müller
Keyword(s):  
Kinetic Energy ◽  
Physical Quantity ◽  
Molecular Motion ◽  
Internal State ◽  
Quantum Mechanical ◽  
Molecular Gas ◽  
Human Intervention ◽  
Missing Information ◽  
Mechanical Dispersion ◽  
The Individual

The equivalence between information and entropy is used to interpret the entropy of a molecular gas as missing information about its internal state of motion. Our considerations show that thermodynamic information is principally composed of two parts which continually change in the course of gas-kinetic collisions. While the first part relates to energy carried by the individual molecules in the form of kinetic energy and in internal excitations, the second relates to information concerned with the location of the molecules within their own mean-free volumes. It is shown that this second kind of information is generated in gas-kinetic collisions and rapidly deteriorated and lost by quantum mechanical dispersion until it is re-gained in follow-on collisions. It is proposed that gas-kinetic collisions can be regarded as measurement processes in which information is continually gained, deteriorated and erased. As these processes occur naturally without any human intervention, it is argued that thermodynamic information—like entropy—fully qualifies as an objective physical quantity.

scholarly journals Relationships between Interaction Energy and Electron Density Properties for Homo Halogen Bonds of the [(A)nY–X···X–Z(B)m] Type (X = Cl, Br, I)

Molecules ◽  
2019 ◽  
Vol 24 (15) ◽  
pp. 2733 ◽  
Author(s):  
Maxim L. Kuznetsov
Keyword(s):  
Kinetic Energy ◽  
Interaction Energy ◽  
Electron Density ◽  
Bond Critical Point ◽  
Kinetic Energy Density ◽  
Large Set ◽  
Halogen Bonds ◽  
Absolute Deviation ◽  
The Individual ◽  
Best Estimator

Relationships between interaction energy (Eint) and electron density properties at the X···X bond critical point or the d(X···X) distance were established for the large set of structures [(A)nY–X···X–Z(B)m] bearing the halogen bonds Cl···Cl, Br···Br, and I···I (640 structures in total). The best estimator of Eint is the kinetic energy density (Gb), which reasonably approximates the whole set of the structures as −Eint = 0.128Gb2 − 0.82Gb + 1.66 (R2 = 0.91, mean absolute deviation 0.39 kcal/mol) and demonstrates low dispersion. The potential and kinetic energy densities, electron density, and the d(X···X) distance behave similarly as estimators of Eint for the individual series Cl···Cl, Br···Br, and I···I. A number of the Eint(property) correlations are recommended for the practical application in the express estimates of the strength of the homo-halogen bonds.

The quantum mechanical theory of environmental effects

1960 ◽  
Vol 255 (1280) ◽  
pp. 63-68 ◽  
Keyword(s):  
Wave Function ◽  
Environmental Effects ◽  
Quantum Mechanical ◽  
Mechanical Theory ◽  
Wave Mechanics ◽  
Quantum Mechanical Theory ◽  
The Individual

A basic postulate of wave mechanics is that the wave function of a microscopic system develops in time according to the equation iℏ∂ψ/∂ t = H ψ, where H , the Hamiltonian, is an operator which in general depends upon the time. If, and only if, the Hamiltonian is time-independent, then the solutions of this equation take the form ψ( q, t ) = ∑ n c n Ѱ n ( q )e -1 E n t /ℏ , (2) where the individual terms Ѱ n ( q ) are functions of the co-ordinates alone and the E n are the corresponding eigenvalues of the Hamiltonian, satisfying HѰ n = E n Ѱ n . (3)

scholarly journals The vacuum in Dirac's theory of the positive electron

1934 ◽  
Vol 146 (857) ◽  
pp. 420-441 ◽  
Keyword(s):  
Kinetic Energy ◽  
Infinite Number ◽  
Strong Support ◽  
Negative Energy ◽  
Positive Energy ◽  
Quantum Mechanical ◽  
Normal Density ◽  
Physical Picture ◽  
Negative Energy States ◽  
Energy States

According to a theory proposed by Dirac one has to picture the vacuum as filled with an infinite number of electrons of negative kinetic energy, the electric density of which is, however, unobservable. One can observe only deviations from this "normal" density which either consist of an addition of electrons in states of positive energy or absence of electrons from some of the negative energy states (positive electrons). The discovery of the positive electron and the observed magnitude of the processes involving it give strong support to this view. This theory, as it stands, however, is not complete because it makes use of infinite quantities which are inadmissible in physical equations. It therefore must be understood (and was meant so by Dirac) to be a physical picture showing a way in which the quantum mechanical equations can probably be modified in order to give account of the positive electron and to solve the difficulty connected with the states of negative energy.

scholarly journals Conformity in the collective: differences in hunger affect individual and group behavior in a shoaling fish

2019 ◽  
Vol 30 (4) ◽  
pp. 968-974 ◽  
Author(s):  
Alexander D M Wilson ◽  
Alicia L J Burns ◽  
Emanuele Crosato ◽  
Joseph Lizier ◽  
Mikhail Prokopenko ◽  
...  
Keyword(s):  
Collective Behavior ◽  
Nearest Neighbor ◽  
Collective Motion ◽  
Internal State ◽  
Group Behavior ◽  
Fundamental Interest ◽  
Individual Level ◽  
Group Members ◽  
The Individual ◽  
Nearest Neighbor Distances

Abstract Animal groups are often composed of individuals that vary according to behavioral, morphological, and internal state parameters. Understanding the importance of such individual-level heterogeneity to the establishment and maintenance of coherent group responses is of fundamental interest in collective behavior. We examined the influence of hunger on the individual and collective behavior of groups of shoaling fish, x-ray tetras (Pristella maxillaris). Fish were assigned to one of two nutritional states, satiated or hungry, and then allocated to 5 treatments that represented different ratios of satiated to hungry individuals (8 hungry, 8 satiated, 4:4 hungry:satiated, 2:6 hungry:satiated, 6:2 hungry:satiated). Our data show that groups with a greater proportion of hungry fish swam faster and exhibited greater nearest neighbor distances. Within groups, however, there was no difference in the swimming speeds of hungry versus well-fed fish, suggesting that group members conform and adapt their swimming speed according to the overall composition of the group. We also found significant differences in mean group transfer entropy, suggesting stronger patterns of information flow in groups comprising all, or a majority of, hungry individuals. In contrast, we did not observe differences in polarization, a measure of group alignment, within groups across treatments. Taken together these results demonstrate that the nutritional state of animals within social groups impacts both individual and group behavior, and that members of heterogenous groups can adapt their behavior to facilitate coherent collective motion.

scholarly journals Spatially resolving the thermally inhomogeneous outer atmosphere of the red giant Arcturus in the 2.3 μm CO lines

2018 ◽  
Vol 620 ◽  
pp. A23 ◽  
Author(s):  
K. Ohnaka ◽  
C. A. L. Morales Marín
Keyword(s):  
Spectral Resolution ◽  
Column Density ◽  
High Spectral Resolution ◽  
Molecular Gas ◽  
Very Large Telescope ◽  
Extended Component ◽  
Outer Atmosphere ◽  
Red Giant ◽  
The Individual ◽  
Photospheric Model

Aim. The outer atmosphere of K giants shows thermally inhomogeneous structures consisting of the hot chromospheric gas and the cool molecular gas. We present spectro-interferometric observations of the multicomponent outer atmosphere of the well-studied K1.5 giant Arcturus (α Boo) in the CO first overtone lines near 2.3 μm. Methods. We observed Arcturus with the AMBER instrument at the Very Large Telescope Interferometer (VLTI) at 2.28–2.31 μm with a spectral resolution of 12 000 and at projected baselines of 7.3, 14.6, and 21.8 m. Results. The high spectral resolution of the VLTI/AMBER instrument allowed us to spatially resolve Arcturus in the individual CO lines. Comparison of the observed interferometric data with the MARCS photospheric model shows that the star appears to be significantly larger than predicted by the model. It indicates the presence of an extended component that is not accounted for by the current photospheric models for this well-studied star. We found out that the observed AMBER data can be explained by a model with two additional CO layers above the photosphere. The inner CO layer is located just above the photosphere, at 1.04 ± 0.02 R⋆, with a temperature of 1600 ± 400 K and a CO column density of 1020 ± 0.3 cm−2. On the other hand, the outer CO layer is found to be as extended as to 2.6 ± 0.2 R⋆ with a temperature of 1800 ± 100 K and a CO column density of 1019 ± 0.15 cm−2. Conclusions. The properties of the inner CO layer are in broad agreement with those previously inferred from the spatially unresolved spectroscopic analyses. However, our AMBER observations have revealed that the quasi-static cool molecular component extends out to 2–3 R⋆, within which region the chromospheric wind steeply accelerates.

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