First sighting of ‘neutrino fog’ sparks excitement – but is it bad news for dark matter?

For the first time, physicists have observed glimmers of the ‘neutrino fog’, signals from particles called neutrinos that mimic those expected to be produced by dark matter — the mysterious substance thought to make up the bulk of matter in the Universe. That’s exciting for physicists because it means that detectors have become sensitive enough to pick up signals of dark matter. But there’s a catch: the neutrino signals could obscure the dark-matter signals that scientists are so eager to observe.

Neanderthals and sapiens interbred more recently than previously thought

All people, other than those whose ancestry comes solely from sub-Saharan Africa, have some Neanderthal DNA. Now two studies suggest that it entered our genomes virtually overnight, much more recently than was thought. One study finds that modern humans and Neanderthals interbred in a roughly 7,000-year period starting around 50,500 years ago; the other finds that the mixing took place between 45,000 and 49,000 years ago. The results and other insights come in part from the oldest human genomes ever sequenced: a male Homo sapiens found near Ranis, Germany, and a female Homo sapiens whose remains were discovered in a cave at a site called Zlatý kůň in the Czech Republic.

Galaxy could mirror a young Milky Way

Images of a young galaxy captured by NASA’s James Webb Space Telescope have given astronomers a glimpse of what the Milky Way might have looked like when it first formed. The images capture the galaxy, dubbed Firefly Sparkle after its resemblance to the bioluminescent insects, in the process of being assembled from groups of stars around 600 million years after the beginning of the universe.

Google’s new quantum chip achieves accuracy milestone

Google scientists have demonstrated that, with the right error-correction techniques, quantum computers can perform calculations with increasing accuracy as they are scaled up. The newest chip, Willow, has performed ‘below threshold’ quantum calculations — a key milestone in the quest to build quantum computers that are accurate enough to be useful.

Virtual lab powered by ‘AI scientists’ super-charges biomedical research

Researchers have created a virtual laboratory staffed by ‘AI scientists’ — large language models (LLMs) with defined scientific roles — that collaborate to achieve goals set by people. The team trained one LLM to be the work’s principal investigator (PI) and a second to act as a ‘scientific critic’. The ‘PI’ then trained three further LLMs to support the research efforts. Each worked independently, but the group came together for short ‘team meetings’ overseen by a human. When tasked with designing antibody fragments that can bind to the virus that causes COVID-19, the AI team proposed 92 structures in a fraction of the time it would have taken an all-human research group.

Oceans have never existed on Venus

Earth’s neighbour Venus has never had liquid water on its surface. One theory of the rocky planet’s history posited that after being covered by magma, the planet maintained a temperate climate for billions of years, which allowed oceans of water to form. Researchers used the chemical composition of volcanic gases in Venus’s atmosphere to infer the water content of its interior — a barometer of whether it ever had such oceans. They found only a 6% water content in the gases, suggesting a very dry planet that has never had liquid water on its surface.

How close is AI to human-level intelligence?

How close are we to developing an artificial general intelligence (AGI) — a machine capable of the whole range of cognitive tasks that human brains can handle? Some think that the large language models (LLMs) currently out there already have some of the ingredients in place. One point in these models’ favour is their underlying transformer architecture, which can find statistical patterns in a range of information beyond text, such as audio. Yet there are also signs that transformer-based LLMs have limits. For a start, the data used to train the models are running out.

Two ancient human relatives crossed paths 1.5 million years ago

Some 1.5 million years ago, two ancient hominin species crossed paths on a lake shore in Kenya. Their footprints in the mud were frozen in time and lay undiscovered until 2021. Now, analysis of the impressions reveals that they belonged to Homo erectus, a forebear of modern humans, and the more distant relative Paranthropus boisei. The two individuals walked through the lake area within hours or days of each other — leaving the first direct record of different archaic hominin species coexisting in the same place.