Reversing aging, new insights into weight gain and steps toward a unified theory of everything. This week’s coolest things bring us closer to some of science’s holy grails.
What is it? UK company Tokamak Energy heated plasma to 100 million degrees Celsius in its reactor — a threshold for producing fusion energy.
Why does it matter? While government labs have been able to reach that temperature in enormous machines known as tokamaks, the company said this is the first time a private entity has done it in one of its own. “We are proud to have achieved this breakthrough, which puts us one step closer to providing the world with a new, secure and carbon-free energy source,” said Tokamak Energy CEO Chris Kelsall.
How does it work? Tokamaks are the leading technology for building future nuclear-fusion power plants. The machines use magnetic fields to confine highly energetic particles, called plasma, creating the right conditions for fusion reactions — like those that take place in the sun. The company says its spherical tokamak is more compact and efficient than standard research reactors, and it intends to pilot the world’s first fusion plant in the early 2030s.
What is it? Physicists at Cornell University discovered a previously theorized but unproven role of magnetism in turning metals into superconductors.
Why does it matter? Superconductors — metals that conduct electricity with no resistance — are used in medical imaging and quantum computing, but they are too difficult and expensive for wide application, because most function only at just above absolute zero. But some superconducting materials work at higher temperatures that are less difficult to attain. This research, published in Nature Physics, cracks open one of the long-standing mysteries of these superconductors. “We’d like to understand what makes these high-temperature superconductors work and engineer that property into some other material that is easier to adopt in technologies,” said physicist and senior author Brad Ramshaw.
How does it work? Ramshaw and his team measured what happened as they continuously changed the number of electrons in copper oxide, a high-temp superconductor. At a certain point, the electrons they were mapping seemed to disappear. Modeling different explanations for the surprising phenomenon, they determined that “magnetism seems to appear … and gobble up most of the electrons” right as the metal transitioned into superconductivity. Connecting these two dots could help scientists find superconducting metals with even higher (and therefore easier-to-achieve) transition temperatures.
What is it? Scientists in Sweden and the U.S. may have moved physics one step closer to a unified theory of the universe.
Why does it matter? One of modern physics’ elusive goals is a single theory that can explain the laws of nature at both the universal and atomic (or quantum) levels simultaneously. In a new article in Nature Communications, the researchers used mathematical techniques to explain how gravity emerges from a quantum state. “The challenge is to describe how gravity arises as an ‘emergent’ phenomenon,” said co-author Robert Berman of Sweden’s Chalmers University of Technology. “Just as everyday phenomena — such as the flow of a liquid — emerge from the chaotic movements of individual droplets, we want to describe how gravity emerges from a quantum mechanical system at the microscopic level.”
How does it work? Berman and his collaborators at Chalmers and MIT based their work on a model called the holographic principle, which theorizes that what we observe in the universe originates from information that exists in a lower dimension — the way a two-dimensional film contains all the information needed to project a three-dimensional holographic image. Using mathematical techniques, Berman said, “we managed to formulate an explanation for how gravity emerges by the holographic principle, in a more precise way than has previously been done.” The researchers believe their results could help inform new insights into black holes and dark matter.
After treatment with molecules called Yamanaka factors, epigenetic markers in the kidneys and skin of older mice resembled those of younger ones. Video credit: Salk Institute.
What is it? Salk Institute scientists reversed signs of aging in mice.
Why does it matter? The researchers administered a cocktail of molecules known as Yamanaka factors to healthy middle-aged and elderly mice. The results suggest that the experiment effectively turned back the hands of time without causing deleterious side effects. “At the end of the day, we want to bring resilience and function back to older cells so that they are more resistant to stress, injury and disease,” said Pradeep Reddy, co-first author of a study in Nature Aging. “This study shows that, at least in mice, there’s a path forward to achieving that.”
How does it work? When animals, including humans, age, chemical signatures on their DNA called epigenetic markers change. Previous research has established that the four Yamanaka factors can reset epigenetic patterns associated with aging and lengthen the life spans of mice with a premature aging disease. The Salk researchers gave mice regular doses of the factors from the age of 12–15 months to 22 months — equivalent to 35–50 to 70 years in humans. After treatment, epigenetic markers in kidneys and skin resembled those of younger mice, and injured skin healed better than in control animals.
What is it? Irish and German scientists pinpointed a way that the immune system mediates diet-related weight gain.
Why does it matter? The findings, published in Science Translational Medicine, further our understanding of the role inflammation plays in the development of obesity. What’s more, said co-author Padraic Fallon, of Trinity College Dublin’s School of Medicine, the discovery has broad impacts for addressing how obesity influences the severity of other diseases, such as COVID-19.
How does it work? People with obesity are more likely to develop conditions such as diabetes, cardiovascular disease and cancer. Scientists are still trying to figure out how inflammation (an immune response) contributes to obesity and related health issues. The researchers pinpointed a “checkpoint protein” on a particular type of immune cell that appears to limit inflammation in fat. Without that functional immune checkpoint, mice fed a “Western high-fat diet” gained more weight and developed signs of diabetes. Changes in that protein were also found to correlate with obesity in humans.