Energy localization on q-tori, long-term stability, and the interpretation of Fermi-Pasta-Ulam recurrences.

Phys Rev E Stat Nonlin Soft Matter Phys

Department of Mathematics, University of Patras, Patras, Greece.

Published: January 2010

We focus on two approaches that have been proposed in recent years for the explanation of the so-called Fermi-Pasta-Ulam (FPU) paradox, i.e., the persistence of energy localization in the "low-q " Fourier modes of Fermi-Pasta-Ulam nonlinear lattices, preventing equipartition among all modes at low energies. In the first approach, a low-frequency fraction of the spectrum is initially excited leading to the formation of "natural packets" exhibiting exponential stability, while in the second, emphasis is placed on the existence of "q breathers," i.e., periodic continuations of the linear modes of the lattice, which are exponentially localized in Fourier space. Following ideas of the latter, we introduce in this paper the concept of " q-tori" representing exponentially localized solutions on low-dimensional tori and use their stability properties to reconcile these two approaches and provide a more complete explanation of the FPU paradox.

Download full-text PDF

Source
http://dx.doi.org/10.1103/PhysRevE.81.016210DOI Listing

Publication Analysis

Top Keywords

energy localization
8
fpu paradox
8
exponentially localized
8
localization q-tori
4
q-tori long-term
4
long-term stability
4
stability interpretation
4
interpretation fermi-pasta-ulam
4
fermi-pasta-ulam recurrences
4
recurrences focus
4

Similar Publications

Microgrid systems have evolved based on renewable energies including wind, solar, and hydrogen to make the satisfaction of loads far from the main grid more flexible and controllable using both island- and grid-connected modes. Albeit microgrids can gain beneficial results in cost and energy schedules once operating in grid-connected mode, such systems are vulnerable to malicious attacks from the viewpoint of cybersecurity. With this in mind, this paper explores a novel advanced attack model named the false transferred data injection (FTDI) attack aiming to manipulatively alter the power flowing from the microgrid to the upstream grid to raise voltage usability probability.

View Article and Find Full Text PDF

Azurin, a bacterial blue-copper protein, has garnered significant attention as a potential anticancer drug in recent years. Among twenty Pseudomonas aeruginosa isolates, we identified one isolate that demonstrated potent and remarkable azurin synthesis using the VITEK 2 system and 16S rRNA sequencing. The presence of the azurin gene was confirmed in the genomic DNA using specific oligonucleotide primers, and azurin expression was also detected in the synthesized cDNA, which revealed that the azurin expression is active.

View Article and Find Full Text PDF

The Role of Ion-Polaron Electrostatic Attraction on Zn Migration in α-VO for Zinc Ion Battery: Insights from First-Principles Calculations.

J Phys Chem Lett

January 2025

Institute for Sustainable Energy/Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, China.

The migration of Zn ions is significantly more challenging compared to that of Li ions within the same crystalline framework, leading to poor rate performance of zinc-ion batteries (ZIBs). Compared to Li, the slower migration rate of Zn is vaguely attributed to the stronger electrostatic interaction induced by Zn. Herein, the rule of how the size of the migration channel and electrostatic interaction affect Zn and Li migration in α-VO has been systematically investigated by first-principle calculations.

View Article and Find Full Text PDF

Type-2-diabetes is a metabolic disorder where misfolding and oligomerization of islet amyloid polypeptide (IAPP) around islet-β cells oligomerizes and participates in the pathology. The oligomeric stage is toxic but transitory and leads to the formation of mature amyloid fibrils. The pathological specifics of mature amyloid fibrils are poorly understood.

View Article and Find Full Text PDF

Purpose: To investigate the feasibility and safety of MRI-guided focal laser ablation (FLA) in localized, International Society of Urological Pathology (ISUP) grade 1-3, prostate cancer (PCa) using an integrated system.

Methods: Ten consecutive males (mean age: 66±7 years) with low-to-intermediate risk PCa were prospectively included (April 2022-May 2023) and treated with MRI-guided FLA using an integrated system for laser energy control and MR thermometry monitoring. Primary endpoints were technical success, procedure-related adverse events (AEs) following SIR (Society of Interventional Radiology) classification, and 12-months local tumor progression-free survival (LTPFS), defined as no evident residual/ recurrent disease on follow-up imaging or histopathology at the treatment site.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!