AI Article Synopsis
- Understanding the accelerated expansion of the Universe is a major challenge in physics, primarily linked to the mysterious role of dark energy.
- Researchers are focusing on the equation of state parameter w(z) to gather clues about dark energy's origin through its redshift evolution.
- A new nonparametric method using Gaussian process modeling and Markov chain Monte Carlo sampling has been developed to accurately reconstruct w(z), applying it to recent supernova data to trace its history up to redshift z=1.5.
Article Abstract
Understanding the origin of the accelerated expansion of the Universe poses one of the greatest challenges in physics today. Lacking a compelling fundamental theory to test, observational efforts are targeted at a better characterization of the underlying cause. If a new form of mass-energy, dark energy, is driving the acceleration, the redshift evolution of the equation of state parameter w(z) will hold essential clues as to its origin. To best exploit data from observations it is necessary to develop a robust and accurate reconstruction approach, with controlled errors, for w(z). We introduce a new, nonparametric method for solving the associated statistical inverse problem based on Gaussian process modeling and Markov chain Monte Carlo sampling. Applying this method to recent supernova measurements, we reconstruct the continuous history of w out to redshift z=1.5.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1103/PhysRevLett.105.241302 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Feeding- and Light-Cycle Synergistically Regulate Mouse Blood Pressure Daily Rhythm via -Dependent and Independent Mechanisms.
J Biol Rhythms
January 2025
Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky.
Cardiovascular health requires the orchestration of the daily rhythm of blood pressure (BP), which responds to changes in light exposure and dietary patterns. Whether rhythmic light and feeding can modulate daily BP rhythm directly or via modulating intrinsic core clock gene is unknown. Using inducible global knockout mice (iBmal1KO), we explored the impact of rhythmic light, rhythmic feeding, or their combination on various physiological parameters.
View Article and Find Full Text PDFPreparation and Performance Study of MXene-Regulated Ethylene Glycol-Induced WO Film.
Micromachines (Basel)
December 2024
College of Materials and Metallurgy, Guizhou University, Guiyang 550025, China.
This study introduces the development of a W-M electrochromic film, characterized by a "coral"-like TiO@WO heterostructure, synthesized via a hydrothermal process leveraging the inherent instability of MXene. The film showcases exceptional electrochromic performance, with a coloring response time of 2.8 s, a bleaching response time of 4.
View Article and Find Full Text PDFComparison of Interactions Between Soy Protein Isolate and Three Folate Molecules: Effect on the Stabilization, Degradation, and Oxidization of Folates and Protein.
Foods
December 2024
Institute of Biopharmaceutical Research, Liaocheng University, Liaocheng 252059, China.
This study selected three approved folate sources-folic acid (FA), L-5-methyltetrahydrofolate (MTFA), and calcium 5-methyltetrahydrofolate (CMTFA)-to explore their interaction mechanisms with soy protein isolate (SPI) through spectrofluorometric analysis and molecular docking simulations. We investigated how these interactions influence the structural and physicochemical stability of folates and SPI. Three folates spontaneously bound to SPI, forming complexes, resulting in a decrease of approximately 30 kJ·mol in Gibbs free energy and an association constant (K) of 10 L·mol.
View Article and Find Full Text PDFEffects of the Quantum Vacuum at a Cosmic Scale and of Dark Energy.
Entropy (Basel)
November 2024
Departamento de Física, Universidad de Cantabria, 39005 Santander, Spain.
The Einstein equation in a semiclassical approximation is applied to a spherical region of the universe, with the stress-energy tensor consisting of the mass density and pressure of the ΛCDM cosmological model plus an additional contribution due to the quantum vacuum. Expanding the equation in powers of Newton constant G, the vacuum contributes to second order. The result is that at least a part of the acceleration in the expansion of the universe may be due to the quantum vacuum fluctuations.
View Article and Find Full Text PDFLong-lasting antimicrobial effect of multipurpose ZnO nanoparticle-loaded dental resins enhanced by blue light photodynamic therapy.
Dent Mater
January 2025
Department of Oral Health Sciences, Faculty of Dentistry, The University of British Columbia, 2199 Wesbrook Mall, room 352, BC V6T-1Z3, Canada. Electronic address:
Objectives: This study aimed to assess the potential of experimental dental resins containing ZnO nanoparticles (ZnO-NPs) for antimicrobial photodynamic therapy (aPDT) as a functional tool for the modulation of cariogenic biofilm in long-term.
Methods: Minimum inhibitory and bactericidal concentrations (MIC/MBC) of ZnO-NPs against Streptococcus mutans were initially determined under different energy densities of blue LED irradiation (0.00, 1.
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!