Experts in the News

Recent demonstrations of moiré magnetism, featuring exotic phases with noncollinear spin order in the twisted van der Waals (vdW) magnet chromium triiodide CrI3, have highlighted the potential of twist engineering of magnetic (vdW) materials. In this paper, researchers, including School of Physics assistant professors Hailong Wang and Chunhui Du, reported the observation of two distinct magnetic phase transitions with separate critical temperatures within a moiré supercell of small-angle twisted double trilayer CrI3.

A team of researchers, led by Georgia Tech alumna Feifei Qian and School of Earth and Atmospheric Sciences Assistant Professor Frances Rivera-Hernández, continue to work on the LASSIE Project, which stands for Legged Autonomous Surface Science in Analogue Environments. They want to see just how well a four-legged robot could make it up Mount Hood’s gravel and snow. “It’s literally a robotic dog form,” said Qian. “It can plow. It can basically dig a hole.” She added, "the information the robot sends back with each step could tell scientists whether it’s good to build a structure in a certain spot on the moon or whether it’d be good to excavate."

A geologically rapid Neoproterozoic oxygenation event is commonly linked to the appearance of marine animal groups in the fossil record. However, there is still debate about what evidence from the sedimentary geochemical record—if any—provides strong support for a persistent shift in surface oxygen immediately preceding the rise of animals. In this article, a team of researchers, including School of Earth and Atmospheric Sciences Postdoctoral Scholar Devon Cole, combined approaches from statistical learning, biogeochemical modeling and ecophysiology to better constrain changes in global ocean biogeochemistry and marine animal habitats through the Neoproterozoic and Palaeozoic eras.

With global ocean heat at record levels, scientists have confirmed that a global coral bleaching event is underway. In an article published in The Conversation, School of Earth and Atmospheric Sciences Professor Annalisa Bracco discusses how research on reef connectivity and resilience may open new avenues for helping corals survive. 

An article published in NewScientist reveals that Antarctica’s melting ice sheets may retreat faster than previously thought. Scientists from the British Antarctic Survey and the University of Oxford discovered that Antarctica’s melting ice sheets may retreat more quickly as warm seawater intrudes underneath them, leading to more melting and faster sea level rise. 

Their findings are built off a model developed by School of Earth and Atmospheric Sciences Associate Professor Alexander Robel and other researchers. Robel’s model found extensive intrusions could more than double the amount of ice loss from an ice sheet by adding heat from below and lubricating the flow of ice along the bedrock. “That positive feedback can cause there to be much more intrusion than we thought possible,” says Robel. “Whether that will be a tipping point that will lead to unrestrained incursion of seawater under the ice sheet – that’s probably a stretch.”

An observatory still under construction at the bottom of the Mediterranean Sea has spotted what could be the most energetic neutrino ever detected. Such ultra-high-energy neutrinos — tiny subatomic particles that travel at nearly the speed of light — have been known to exist for only a decade or so, and are thought to be messengers from some of the Universe’s most cataclysmic events, such as growth spurts of supermassive black holes in distant galaxies. “It would be really interesting to see where in the sky the neutrino originated,” says Nepomuk Otte, an associate professor in the School of Physics. Otte is leading a proposed project — with a prototype now being tested in Utah — that would search for Earth-skimming neutrinos by monitoring the atmosphere just above the horizon for flashes of light.

Frequently wearing high heels could help you walk more efficiently in flat shoes, according to a new study published in The Journal of Applied Physiology. Researchers at the University of Texas at Austin and Georgia Institute of Technology, including Gregory S. Sawicki, associate professor in the School of Biological Sciences and the School of Mechanical Engineering, found that donning stilettos could help strengthen the tendons in the ankles and calves, making the legs more powerful.

Knitting, the age-old craft of looping and stitching natural fibers into fabrics, is gaining renewed attention for its potential in advanced manufacturing. Beyond creating garments, knitted textiles hold promise for designing wearable electronics and soft robotics – structures that need to move and bend flexibly. A team of physicists from the Georgia Institute of Technology has taken the technical know-how of knitting and added a mathematical foundation to it. Led by Elisabetta Matsumoto, associate professor in the School of Physics, and Krishma Singal, a graduate researcher in Matsumoto’s lab, the team used experiments and simulations to quantify and predict how knitted fabric responses can be programmed.

A series of four earthquakes in a week around Lake Lanier have had residents wondering two questions -- why are they happening, and when will they stop?

On Friday, researchers from several Georgia universities began placing special earthquake sensors below ground. The seismic nodes will sit about one foot deep and will be placed in several locations surrounding the epicenters. The first seismic sensor was installed at Sugar Hill Elementary School in Gwinnett County. R. Scott Harris, University of Georgia adjunct researcher and STEM educator with Gwinnett County Public Schools, and School of Earth and Atmospheric Sciences Professor Zhigang Peng, dug through the Georgia Clay to reach the right depth and placed the sensor and battery system below ground, to be later retrieved later this year.

"There are probably many smaller ones that are happening right now as we speak, but it's always hard to tell when it's going to stop. That's the Million-Dollar question. That's what we're trying to figure out," Dr. Peng explained.

Elephants use their trunks for various tasks by exploiting a remarkable range of motions. A research team has now shown that much of this dexterity can be achieved using just a small number of muscle-like actuators. Using both theoretical calculations and experiments with a simple physical model of a trunk, the researchers found that their minimal model can reproduce the complex bending and torsional motions seen in real trunks. The results might be useful in the design of “soft robotics” devices.

David Hu, professor in the School of Biological Sciences and the School of Mechanical Engineering, calls the work “a triumph of mathematics and an important step in reverse engineering the elephant trunk.” He says that the important result is in “reducing the biological complexity to three degrees of freedom.” 

Hu adds that “the big question left in my mind is this: If elephants can achieve all these 3D trunk positions with just three actuators, why does it have to have so many other muscles, and when are those used?”

The Peach State is not typically a hotbed of seismic activity, but residents in pockets of North Georgia have been feeling some unexpected vibrations lately after the area has been jolted by five small earthquakes over the last 10 days. 

Georgia is located in the middle of the North American Plate, the vast tectonic plate that sits beneath almost all of North America, parts of the Caribbean, Greenland and much of the Atlantic Ocean. Earthquakes — particularly strong ones — are much more likely in places like California, which sit along major plate boundaries.

Still, small earthquakes are fairly common in Georgia, experts say. The state typically experiences between 10 and 20 earthquakes above magnitude 2.0 each year, said Andy Newman, professor and associate chair for Undergraduate Studies in the School of Earth and Atmospheric Sciences.

The three earthquakes at Lake Lanier’s southern end represent a “swarm” of seismic activity, but scientists say such clusters are also common.

“Generally, if you have one earthquake, the best place to guess where the next earthquake is going to occur is right near the same location,” Newman said.

(This also appeared at Macon Telegraph and Phys.org.)

Learning more about how microorganisms operate in space has long been a critical part of avoiding contamination of all NASA experiments conducted in space and on the moon.

"NASA has a responsibility to ensure that science measurements made on Mars are not impacted by microbes brought from Earth. When humans go to Mars we will bring trillions of microbes with us, carried in our gut and on our skin," said Christopher Carr, assistant professor in the School of Earth and Atmospheric Sciences and the School of Aerospace Engineering.