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Imagine you’re walking to work when the unspeakable occurs: Your favorite coffee shop—where you stop every day—is closed. You groggily navigate to a newly opened coffee shop a couple blocks away, which, you’re pleased to discover, actually makes quite a good morning brew. Soon, you find yourself looking forward to stopping at the new location instead of the old one.

That switch probably alters more than just your morning routine. Each time you visit that new coffee shop, the experience likely strengthens a neural map marking the positions of rewarding experiences—a map that can guide you back to those experiences even from miles away.

While the existence of a reward map is familiar from previous work, Wu Tsai Neuro researchers working with were surprised to find that the map persists even when mice move many meters away from a treat, and that it updates almost immediately when the of the treat changes.

In a new study, physicists at the University of Colorado Boulder have used a cloud of atoms chilled down to incredibly cold temperatures to simultaneously measure acceleration in three dimensions—a feat that many scientists didn’t think was possible.

The device, a new type of atom “interferometer,” could one day help people navigate submarines, spacecraft, cars and other vehicles more precisely.

“Traditional atom interferometers can only measure acceleration in a single dimension, but we live within a three-dimensional world,” said Kendall Mehling, a co-author of the new study and a graduate student in the Department of Physics at CU Boulder. “To know where I’m going, and to know where I’ve been, I need to track my acceleration in all three dimensions.”

Perovskite has broad application prospects in solar cells, light-emitting diodes (LEDs), and detectors due to its high luminescent efficiency and low cost. However, electrons and holes in traditional perovskite materials often struggle to effectively recombine and emit light. As a result, the strongly space-confined method is commonly employed to improve luminescence efficiency. Furthermore, how to enhance the brightness of LEDs and extend their lifespan has become a top research priority in this field.

In a study published in Nature, Prof. Xiao Zhengguo’s team from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences has proposed a novel strategy based on weakly space-confined, large-grain crystals of all-inorganic perovskite to prepare with larger crystalline grains and higher temperature resistance. Researchers increased the brightness of perovskite LEDs (PeLEDs) to over 1.16 million nits and extended their lifespan to more than 180,000 hours.

Researchers developed the strategy based on the weakly space-confined technique. They first added specific compounds—hypophosphorous acid and ammonium chloride—to the perovskite material. Then, they prepared a new type of perovskite thin film with larger crystalline grains and fewer defects using a high-temperature annealing process.

Mercury levels in the world’s rivers have more than doubled since the pre-industrial era, according to new research from Tulane University that establishes the first known global baseline for riverine mercury pollution.

The study, published in Science Advances, developed a process-based model to simulate mercury transport in rivers and found that global rivers carried approximately 390 metric tons of mercury to the oceans annually before 1850. Today, that figure has jumped to about 1,000 metric tons per year.

Primary drivers of the increase are wastewater discharge, soil erosion and mercury releases from industrial activities and mining, said lead author Yanxu Zhang, associate professor of Earth and environmental sciences at Tulane School of Science and Engineering.

Randomness is incredibly useful. People often draw straws, throw dice or flip coins to make fair choices. Random numbers can enable auditors to make completely unbiased selections. Randomness is also key in security; if a password or code is an unguessable string of numbers, it’s harder to crack. Many of our cryptographic systems today use random number generators to produce secure keys.

But how do you know that a random number is truly random?

Classical computer algorithms can only create pseudorandom numbers, and someone with enough knowledge of the algorithm or the system could manipulate it or predict the next number. An expert in sleight of hand could rig a coin flip to guarantee a heads or tails result. Even the most careful coin flips can have bias; with enough study, their outcomes could be predicted.

A research team has observed multibody interaction-induced EPs and hysteresis trajectories in cold Rydberg atomic gases. They revealed the phenomenon of charge-conjugation parity (CP) symmetry breaking in non-Hermitian multibody physics.

The team was led by Prof. Guo Guangcan, Prof. Shi Baosen and Prof. Ding Dongsheng from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences, and their study was published in Nature Communications.

CP-symmetry is an important discrete symmetry in . When certain physical processes exhibit asymmetry under CP transformation, it is referred to as the breaking of CP-symmetry, such as in the decay of neutral K mesons (K⁰) and B meson decay.

Once only a part of science fiction, lasers are now everyday objects used in research, health care and even just for fun. Previously available only in low-energy light, lasers are now available in wavelengths from microwaves through X-rays, opening a range of different downstream applications.

In a study published in Nature, an led by scientists at the University of Wisconsin–Madison has generated the shortest hard X-ray pulses to date through the first demonstration of strong lasing phenomena.

The resulting pulses can lead to several potential applications, from quantum X-ray optics to visualizing inside molecules.

A research team led by Prof. Zhang Tianshu at the Hefei Institutes of Physical Science of the Chinese Academy of Sciences has developed a compact all-solid-state continuous-wave (CW) single-longitudinal-mode (SLM) laser with high frequency stability using iodine-based frequency locking, advancing its application in atmospheric remote sensing and environmental monitoring. The study is published in Optics and Laser Technology.

CW SLM lasers are widely used in areas such as laser amplification, , and quantum optics. They also play a key role in atmospheric remote sensing and . These applications require not only SLM laser output but also high frequency stability, which current semiconductor and fiber lasers struggle to provide due to limited environmental adaptability.

In this study, the team introduced a ring resonator structure combined with iodine molecular absorption frequency locking technology. By locking the laser frequency to the flank of specific iodine absorption lines and employing feedback control to adjust the resonator length, they achieved long-term frequency stability.

Mysterious seismic signals from massive North Atlantic storms are rippling through Earth’s core and surfacing in remote Australia. Scientists from the Australian National University (ANU) have discovered that powerful winter storms in the North Atlantic Ocean send energy waves deep through the Ea