Lagrangian Mechanics is the basis of modern Physics. In this article, we’ll discuss various Lagrangians and show how waves could explain everything.
Category: physics – Page 182
MIT scientists create color-shifting films inspired by 19th-century holography
Potential applications include pressure-monitoring bandages, shade-shifting fabrics.
The bright iridescent colors in butterfly wings or beetle shells don’t come from any pigment molecules but from how the wings are structured—a naturally occurring example of what physicists call photonic crystals. Scientists can make their own structural colored materials in the lab, but it can be challenging to scale up the process for commercial applications without sacrificing optical precision.
A wild twist on a modern technology could unleash nuclear fusion
Overall, the experiment represents steps forward in understanding fundamental physics and applies to much more macroscale phenomena.
Research finds mechanically driven chemistry accelerates reactions in explosives
Scientists at the Lawrence Livermore National Laboratory (LLNL) Energetic Materials Center and Purdue University Materials Engineering Department have used simulations performed on the LLNL supercomputer Quartz to uncover a general mechanism that accelerates chemistry in detonating explosives critical to managing the nation’s nuclear stockpile. Their research is featured in the July 15 issue of the Journal of Physical Chemistry Letters.
Insensitive high explosives based on TATB (1,3,5-triamino-2,4,6-trinitrobenzene) offer enhanced safety properties over more conventional explosives, but physical explanations for these safety characteristics are not clear. Explosive initiation is understood to arise from hotspots that are formed when a shockwave interacts with microstructural defects such as pores. Ultrafast compression of pores leads to an intense localized spike in temperature, which accelerates chemical reactions needed to initiate burning and ultimately detonation. Engineering models for insensitive high explosives—used to assess safety and performance—are based on the hotspot concept but have difficulty in describing a wide range of conditions, indicating missing physics in those models.
Using large-scale atomically resolved reactive molecular dynamics supercomputer simulations, the team aimed to directly compute how hotspots form and grow to better understand what causes them to react.
India’s AstroSat witnessing the ‘live’ formation of dwarf galaxies
Dwarf galaxies are small galaxies composed of a few billion stars. They are challenging to detect due to their low luminosity, low mass, and small size. However, it remains elusive how these dwarf and giant galaxies assemble their stars and evolve into modern-day galaxies.
India’s first dedicated multi-wavelength space observatory, AstroSat, cracked this mystery. A team of scientists using AstroSat shows how the star-forming complexes in the outskirts of a dwarf galaxy migrate towards the central region and contribute to its growth in mass and luminosity.
The team includes astronomers from India, the USA, and France. Professor Kanak Saha at the Inter-University Centre for Astronomy and Astrophysics (IUCAA), Pune, conceived this study. Mr. Anshuman Borgohain is the lead author of the paper.
Dark Matter: Is a Revolution Coming to Physics?
What is dark matter? Does it even exist, or do we just need an adjustment to our theory of gravity?
What is dark matter? It has never been observed, yet scientists estimate that it makes up 85% of the matter in the universe. The short answer is that no one knows what dark matter is. More than a century ago, Lord Kelvin offered it as an explanation for the velocity of stars in our own galaxy. Decades later, Swedish astronomer Knut Lundmark noted that the universe must contain much more matter than we can observe. Scientists since the 1960s and ’70s have been trying to figure out what this mysterious substance is, using ever-more complicated technology. However, a growing number of physicists suspect that the answer may be that there is no such thing as dark matter at all.
Scientists can observe far-away matter in a number of ways. Equipment such as the famous Hubble telescope measures visible light while other technology, such as radio telescopes, measures non-visible phenomena. Scientists often spend years gathering data and then proceed to analyze it to make the most sense of what they are seeing.
Roboticists Developed an AI Program That May Have Discovered an ‘Alternative Physics’
Artificial Intelligence has ushered the advancement of several disciplines throughout the years. But could it ever discover a new form of physics?
A group of roboticists from Columbia University wanted to exploit the vast potential of AI and find out if it can ever find an “alternative physics.”
Hence, they created an AI tool that could recognize physical occurrences and identify pertinent variables, essential building blocks for every physics theory.
Scientists fabricate high-performance large-area perovskite submodules for solar cells
Perovskite solar cells (PSCs) are promising solar technologies. Although low-cost wet processing has shown advantages in small-area PSC fabrication, the preparation of uniform charge transport layers with thickness of several nanometers from solution for meter-sized large area products is still challenging.
Recently, a research group led by Prof. LIU Shengzhong from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) has developed a facile surface redox engineering (SRE) strategy for vacuum-deposited NiO x to match the slot-die-coated perovskite, and fabricated high-performance large-area perovskite submodules.
This work was published in Joule (“Surface redox engineering of vacuum-deposited NiO x for top-performance perovskite solar cells and modules”).