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Study introduces novel conservation law that operates down to the subcycle level during strong-field ionization

The conservation law is a fundamental tool that significantly aids our quest to understand the world, playing a crucial role across various scientific disciplines. Particularly in strong-field physics, these laws enhance our comprehension of atomic and molecular structures as well as the ultrafast dynamics of electrons.

Forget Black Holes—White Holes Would Break Your Puny Brain

White holes, the theoretical opposites of black holes, could expel matter instead of absorbing it. Unlike black holes, whose event horizon traps everything, white holes would prevent anything from entering. While no white holes have been observed, they remain an intriguing mathematical possibility. Some astrophysicists have speculated that gamma ray bursts could be linked to white holes, and even the Big Bang might be explained by a massive white hole. Although the second law of thermodynamics presents a challenge, studying these singularities could revolutionize our understanding of space-time and cosmic evolution.

After reading the article, Harry gained more than 724 upvotes with this comment: “It amazes me how Einstein’s theory and equations branched off into so many other theoretical phenomena. Legend legacy.”

Black holes may well be the most intriguing enigmas in the Universe. Believed to be the collapsed remnants of dead stars, these objects are renowned for one characteristic in particular – anything that goes in never comes out.

A physicist and his cat ‘reveal’ the equation of cat motion

In the social media age, there is little doubt about who is the star of the animal kingdom. Cats rule the screens just as their cousins, the lions, rule the savanna. Thanks to Erwin Schrödinger, this feline also has a place of honor in the history of physics. And it was Eme the cat that inspired Anxo Biasi, researcher at the Instituto Galego de Física de Altas Enerxías (IGFAE), to publish an article in the American Journal of Physics.

Measurement of Ascorbic Acid Samples’ Optical Rotation via an Improvised Polarimeter for Purity Assessment

The polarization of light finds practical application in physics and chemistry through the optical activity phenomenon, where polarimeters play a crucial role. This research builds on the improvised polarimeter designed by Kvittingen and Sjursnes, implemented with relevant modifications, to measure optical rotations of over-the-counter ascorbic acid samples. The study aims to assess the purity of two brands of ascorbic acid through polarimetry, comparing the calculated specific rotation with the literature values and supplementing the characterization with melting point determination. The constructed polarimeter, assembled using Lego bricks, provides an affordable alternative for educational purposes, addressing the challenges observed in the accessibility of commercial polarimeters for classroom demonstrations. The methodology encompasses pre-experiment steps involving polarimeter construction, the experiment utilizing polarimetry and complementary melting point determination, and post-experiment analysis to determine specific rotation from the measured optical rotations. Results indicate that Brand X exhibited specific rotations close to theoretical values, inferring high purity. Conversely, Brand Y shows significant deviations, suggesting potential impurities. These conclusions are supported by melting point data. The comprehensive approach combining polarimetry and melting point determination enhances the reliability of purity assessments, showcasing the effectiveness of the improvised polarimeter in practical applications.

R J M Felicidario and R M delos Santos 2024 J. Phys.: Conf. Ser. 2,871 012009.

Bach, Mozart or jazz: Scientists provide a quantitative measure of variability in music pieces

Physicists at the Max Planck Institute for Dynamics and Self-Organization (MPI-DS) have investigated to which extent a piece of music can evoke expectations about its progression. They were able to determine differences in how far compositions of different composers can be anticipated. In total, the scientists quantitatively analyzed more than 550 pieces from classical and jazz music.

Crazy AI Learned Minecraft — Try It Out For Free!

❤️ Check out Lambda here and sign up for their GPU Cloud: https://lambdalabs.com/papers.

Oasis: A Universe in a Transformer — try it out now:
https://oasis.decart.ai/welcome.

More info:
https://oasis-model.github.io/

📝 My paper on simulations that look almost like reality is available for free here:
https://rdcu.be/cWPfD

Or this is the orig. Nature Physics link with clickable citations:
https://www.nature.com/articles/s41567-022-01788-5

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Hawking radiation may unveil hidden physics in black hole explosions

Detecting exploding primordial black holes from the universe’s first second may unveil new physics.


In that moment, pockets of hot material may have been dense enough to form black holes, potentially with masses ranging from 100,000 times less than a paperclip to 100,000 times more than the sun’s, according to scientists.

Then, as the universe quickly expanded and cooled, the conditions for forming black holes this way ended.

Scientists are now claiming that PBHs may be heating up and exploding throughout the universe.

Physics for excited neurons

“Badass”. That was the word Harvard University neuroscientist Steve Ramirez used in a Tweet to describe research published online by fellow neuroscientist Ali Güler and colleagues in the journal Nature Neuroscience last March. Güler’s group, based at the University of Virginia in the US, reported having altered the behaviour of mice and other animals by using a magnetic field to remotely activate certain neurons in their brains. For Ramirez, the research was an exciting step forward in the emerging field of “magnetogenetics”, which aims to use genetic engineering to render specific regions of the brain sensitive to magnetism – in this case by joining proteins containing iron with others that control the flow of electric current through nerve-cell membranes.

By allowing neurons deep in the brain to be switched on and off quickly and accurately as well as non-invasively, Ramirez says that magnetogenetics could potentially be a boon for our basic understanding of behaviour and might also lead to new ways of treating anxiety and other psychological disorders. Indeed, biologist Kenneth Lohmann of the University of North Carolina in the US says that if the findings of Güler and co-workers are confirmed then magnetogenetics would constitute a “revolutionary new tool in neuroscience”

The word “if” here is important. In a paper posted on the arXiv preprint server in April last year and then published in a slightly revised form in the journal eLife last August, physicist-turned-neuroscientist Markus Meister of the California Institute of Technology laid out a series of what he describes as “back-of-the-envelope” calculations to check the physical basis for the claims made in the research. He did likewise for an earlier magnetogenetics paper published by another group in the US as well as for research by a group of scientists in China positing a solution to the decades-old problem of how animals use the Earth’s magnetic field to navigate – papers that were also published in Nature journals.

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