Category Physics

Using time-lapse videos as training data, computer scientists have developed video generators that simulate the physical world more accurately. While text-to-video artificial intelligence models like OpenAI’s Sora are rapidly metamorphosing in front of our eyes, they have struggled to produce metamorphic videos. Simulating a tree sprouting or a flower blooming is harder for AI systems than generating other types of videos because it requires the knowledge of the physical world and can vary widely.

But now, these models have ta...

In 1959, physicists James Terrell and Roger Penrose (Nobel laureate in 2020) independently concluded that fast-moving objects should appear rotated. However, this effect has never been demonstrated. Now, scientists have succeeded for the first time in reproducing the effect using laser pulses and precision cameras — at an effective speed of light of 2 meters per second.

When an object moves extremely fast — close to the speed of light — certain basic assumptions that we take for granted no longer apply. This is the central consequence of Albert Einstein’s special theory of relativity. The object then has a different length than when it is at rest, and time passes differently for the object than it does in the laboratory. All this has been repeatedly confirmed in experiments.

How...

Altermagnets, which exhibit momentum-dependent spin splitting without spin–orbit coupling (SOC) or net magnetization, have recently attracted significant international attention.

A team led by Prof. Liu Junwei from the Department of Physics at the Hong Kong University of Science and Technology (HKUST), along with their experimental collaborators, published their latest research findings in Nature Physics, which unveiled the first experimental observation of a two-dimensional layered room-temperature altermagnet, validating the theoretical predictions in Nature Communications made by Prof. Liu in 2021.

The realization and control of spin-polarized e...

A quantum computer can solve optimization problems faster than classical supercomputers, a process known as “quantum advantage” and demonstrated by a USC researcher in a paper recently published in Physical Review Letters.

The study shows how quantum annealing, a specialized form of quantum computing, outperforms the best current classical algorithms when searching for near-optimal solutions to complex problems.

“The way quantum annealing works is by finding low-energy states in quantum systems, which correspond to optimal or near-optimal solutions to the problems being solved,” said Daniel Lidar, corresponding author of the study and professor of electrical and computer engineering, chemistry, and physics and astronomy at the USC Viterbi School of Engi...