Special Issue "Feature Papers: Entropy Concepts and Applications"

Editor-in-Chief
Dr. Peter Harremoës
Centrum Wiskunde & Informatica (CWI), Science Park 123, 1098 XG Amsterdam, The Netherlands
Website: http://homepages.cwi.nl/~ph/
E-Mail:
Interests: symmetry, information divergence, cause and effect, Maxwell's demon, probability and statistics

Submission

All papers should be submitted to entropy@mdpi.org with copy to the guest editor. To be published continuously until the deadline and papers will be listed together at the special websites. Both, research articles and review articles are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editors for announcment on this website.

Submitted papers should not have been published previously, nor be under consideration for publication elsewhere. All papers are refereed through a peer-review process. A guide for authors, sample copies and other relevant information for submitting papers are available on the Instructions for Authors page. Entropy is an international peer-reviewed quarterly journal published by Molecular Diversity Preservation International.

Please visit the Instructions for Authors page before submitting a paper. Open Access publication fees are 800 CHF per paper. English correction fees (250 CHF) will be added in certain cases (1050 CHF per paper for those papers that require extensive additional formatting and/or English corrections.).

• invited papers
• feature papers related to entropy research

Title: Application of the Kolmogorov Entropy Algorithm for Flow Regime Identification in a Bubble Column
Authors: Stoyan Nedeltchev^1,2, Oliver Lorenz¹ and Adrian Schumpe¹
Affiations: ¹ Institute of Technical Chemistry, TU Braunschweig Hans-Sommer-Strasse 10, 38106 Braunschweig, Germany; ² Institute of Chemical Engineering, Bulgarian Academy of Sciences “Acad. G. Bontchev” Str. Bl. 103, 1113 Sofia, Bulgaria
Abstract: The behavior of the Kolmogorov entropy (KE) in a bubble column (0.102 m ID) was studied in order to identify the boundaries of the various flow regimes. The column was equipped with a perforated plate distributor (19 × Æ 1 mm) and was operated batchwise with both ethanol (96 %)-nitrogen and tap water-nitrogen systems at ambient pressure and temperature. The KE algorithm was applied to differential pressure fluctuations recorded at a sampling frequency of 100 Hz. The KE estimation involved the following steps: reconstruction of phase space, plot of chaotic attractor and its characterization by the KE. The KE quantifies the rate of information loss. Based on the peaks in the KE values the boundaries of 4 main regimes were identified. It was found that two of them may be additionally divided into subregimes and their boundaries were also identified by means of the KE algorithm.

Title: Entropy in the Present and Early Universe, New Small Parameters at Planck Scale and Dark Energy Problem
Author: Alexander Shalyt-Margolin
Affiliation: National Centre of Particles and High Energy Physics, Bogdanovich Str. 153, Minsk, 20040, Belarus
Abstract: The Dark Energy Problem is investigated within the scope of Vacuum Energy Density approach by the methods of Quantum Field Theory with the UV cutoff (fundamental length). It is noted that for the agreement between the vacuum energy density and experimental astrophysical data such a theory should have the holographic principle as its corollary. It is demonstrated that entropy, its density and also new small parameters emergent at Planck scale play a significant role in solving this problem. Taking this in mind, two most popular models for dark energy - Holographic Dark Energy Model (HDEM) and Agegraphic Dark Energy Model (ADEM) are analyzed. It is shown that at least the fundamental quantities in HDEM may be expressed in terms of this new small parameters. The recent results on the uncertainty principle for the pair "vacuum energy density - volume of space-time", where the vacuum energy density is considered as a dynamic quantity, are reconsidered and generalized up to the Generalized Uncertainty Principle (GUP). In the concluding comments the prospects for solving of the Dark Energy Problem are considered based on the results obtained.