science

In a single sniff, the human sense of smell can distinguish odors within a fraction of a second, working at a level of sensitivity that is “on par” with how our brains perceive color, “refuting the widely held belief that olfaction is our slow sense,” a new study finds.

...

The new findings challenge previous research in which the timing it took to discriminate between odor sequences was around 1,200 milliseconds, Dr. Dmitry Rinberg, a professor in the Department of Neuroscience and Physiology at NYU Langone Health in New York, wrote in an editorial accompanying the study in Nature Human Behaviour.

Cool!

Also, yuck!

cross-posted from: https://lemmy.world/post/20847663

Scientists had previously observed sleeping birds making movements that resembled lip-syncing. In earlier work, Mindlin and his colleagues implanted electrodes in two Zebra Finches; for a recent study in Chaos, they did the same for two Great Kiskadees. This let them record and compare neuron and muscle activity in the sleeping birds.

When awake, Zebra Finches sing a well-regulated line of staccato notes. But their sleeping song movements are fragmented, disjointed and sporadic—“rather like a dream,” Mindlin says. A dozing finch seems to silently practice a few “notes” and then add another, producing a pattern of muscle activity that reminds Mindlin “of learning a musical instrument.”

Jupiter pics. still don't know why

Imagine three people huddled in a circle so when one speaks, only one other hears. Scientists have created a device that works like that, ensuring sound waves ripple in one direction only.

The device, developed by scientists at ETH Zurich and the Swiss Federal Institute of Technology Lausanne, is made up of a disk-shaped cavity with three equally-spaced ports that can each send or receive sound.

In an inactive state, sound transmitted from port 1 is audible to ports 2 and 3 at equal volumes. Sound waves bounce back to port 1 as an echo as well.

When the system is running, however, only port 2 hears port 1's sounds.

The trick is to blow swirling air into the cavity at a specific speed and intensity, which allows the sound waves to synchronize in a repeating pattern. That not only guides the sound waves in a single direction, but gives more energy to those oscillations so they don't dissipate. It's kind of like a roundabout for sound.

The scientists say their technique may inform the design of future communications technologies. New metamaterials could be made to manipulate not just sound waves but potentially electromagnetic waves too.

Please incorporate this technology into TVs so I don't have to hear them through the wall.

Laser-induced imaging of radioactive elements was used to work out the age of an ancient cave painting on the Indonesian island of Sulawesi. The results reveal that the narrative scene is 51,200 years old, making it the earliest known example of representational art. This study challenges previous dating methods and suggests a deeper origin for human image-making and storytelling.

TL;DR or if you don't have access to the article: the researchers invented a faster, less-destructive and more-accurate rock art dating method & applied it to humanity's oldest known rock art in Sulawesi, Indonesia. The art is at least 51,200 years old (authors' lower estimate)!

Edit: contrary to what the news title original stated: this is the oldest representational art, not the literal oldest human-created art.

The paper itself (open access): https://doi.org/10.1038/s41586-024-07541-7

Pham Tiep, the Joshua Barlaz Distinguished Professor of Mathematics in the Rutgers School of Arts and Science's Department of Mathematics, has completed a proof of the 1955 Height Zero Conjecture posed by Richard Brauer, a leading German-American mathematician who died in 1977. Proof of the conjecture -- commonly viewed as one of the most outstanding challenges in a field of math known as the representation theory of finite groups -- was published in the September issue of the Annals of Mathematics.