Nature Briefing: The World’s Most Accurate Clock, a New Brain Atlas and AI’s Research Productivity Debate
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Today’s top science stories
A close-up of the inside of the world’s most accurate timekeeping lutetium clock. Credit: Center for Quantum Technology, National University of Singapore
The world’s most accurate clock could lose just one second in 260 billion years
Physicists have unveiled the world’s most accurate clock. The device is so reliable that it would take more than 260 billion years to lose one second.
The clock is an optical atomic clock, which measures time using frequencies of visible light absorbed by an element. In this case, the element is lutetium, a rare-earth metal. The researchers say the clock is sturdy enough that they hope to miniaturize it so that it can eventually be taken out of the laboratory.
Nature | 5-minute read
Reference: Nature paper
A massive gene-activity map reveals how the human prefrontal cortex changes
Researchers have created the largest map to date of gene activity in the human prefrontal cortex, a brain region involved in planning, decision-making, and the control of behavior and emotion.
The atlas draws on samples from nearly 1,500 people, ranging from infants to centenarians. It includes gene-activity data from more than 6.3 million individual brain cells. Its scale could help researchers study neurodegenerative and psychiatric diseases that affect the prefrontal cortex in unprecedented detail.
Nature | 6-minute read
Reference: PsychAD Consortium Paper Collection
A stretchable new form of boron shows extraordinary conductivity
A newly identified phase of elemental boron can be stretched and has more than a million times the conductivity of typical boron materials.
The structure, called Imma-B60, is the first new unusual form of boron discovered since 2009. Researchers created it by reacting boron with sodium under high pressure and then removing sodium impurities from the mixture.
These properties suggest that the material could one day be used in solar panels or replace existing boron compounds in body armor.
Nature | 4-minute read
Reference: Nature Chemistry paper
Preprint server removes 257 papers linked to concerns about AI-assisted research
The SSRN preprint server removed 257 papers authored or co-authored by US statisticians after others raised concerns about unusual productivity. “It’s not just the quantity, but also the variety of topics and how they differ from his previous works,” said business professor Oyon Siddique.
Author Nicholas Polson told the Washington Post that he used AI tools to create his work. “Obviously, AI makes researchers much more productive,” he said.
Washington Post | 9-minute read
Earth’s core may explain variations in the length of a day
Gravity and other forces caused by the movement of Earth’s metallic core can explain millisecond variations in the length of a 24-hour day over several decades.
Researchers modeled the effects of internal forces produced by interactions between Earth’s inner and outer core and its rocky mantle. These forces can subtly influence the planet’s rotational speed.
The researchers found that one scenario, in which gravitational twisting forces generated by the inner core are dominant, best matches the historical record of changes in day length.
Nature | 5-minute read
Reference: Nature paper
Figure 1 | Gravitational torque causes changes in day length over a decade. Chan and Danbury1 report that multidecadal variations in day length are caused by the gravitational torque exerted on the mantle by Earth’s solid inner core. The inner core has an ellipsoidal shape, with its ellipticity exaggerated in the figure for clarity. This shape is partly due to interactions with two mantle regions called large slow regions. When the inner core is displaced from its equilibrium position, it exerts a gravitational torque on the mantle.
Features and analysis
Could artificial intelligence pose an existential threat?
Researchers and leaders at some of the world’s largest AI companies have expressed concern that artificial intelligence could kill us all. One hypothetical example is the “paperclip problem”: a powerful AI system with a single purpose, such as making paperclips, could sacrifice everything else to achieve that goal.
Others argue that more immediate harms are already occurring, including disinformation and concerns that fallible AI could be used in critical safety systems such as nuclear power plants. Some technology commentators have also argued that exaggerating AI risks could be an attempt to justify slowing development to shareholders or to consolidate power among a few large companies.
Nature | 7-minute read
Why hail is becoming a larger climate and weather threat
Hail is already one of the costliest weather disasters and is expected to worsen with climate change. Researchers in Colorado, one of the most hail-prone parts of the United States, have conducted a comprehensive study of hail on the ground, hail in the air, the storm itself, and the surrounding environment.
“This is the first time we’ve been able to comprehensively look at the hail on the ground, the hail in the air, the storm itself, and the environment around the storm all at once,” said Becky Adams Selin, principal investigator for ICECHIP, the Field Collaborative Experiment for Plains Hail Collection.
Also today: New analysis of the Roman road network
Today we learned that not all roads lead to Rome. This was not necessarily the case during the Roman Empire either. A new analysis of nearly 300,000 kilometres of ancient roads examines how the network connected Constantinople, modern-day Istanbul, Turkey, with other parts of the empire.
Source: www.nature.com