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A high-resolution imaging system captures distant objects by shining laser light on them and detecting the reflected light.

One of astronomers’ tricks for observing distant objects is intensity interferometry, which involves comparing the intensity fluctuations recorded at two separate telescopes. Researchers have now applied this technique to the imaging of remote objects on Earth [1]. They developed a system that uses multiple laser beams to illuminate a distant target and uses a pair of small telescopes to collect the reflected light. The team demonstrated that this intensity interferometer can image millimeter-wide letters at a distance of 1.36 km, a 14-fold improvement in spatial resolution compared with a single telescope.

Interferometry is common in radio astronomy, where the signal amplitudes from a large array of radio telescopes are summed together in a way that depends on the relative phases of the radio waves. Intensity interferometry is something else. It doesn’t involve addition of amplitudes or preservation of phases. Instead, light is recorded from a single source at two separate detectors (or telescopes), and the fluctuations in the intensities of the two signals are compared. Spatial information on the source comes from analyzing how these fluctuations are correlated in time and how this correlation depends on the detector separation.

An atomic magnetometer uses lasers and a gas of atoms, such as rubidium, to detect magnetic fields. The atoms behave like tiny magnetic compasses, with their spins moving in response to magnetic forces. Using two atomic species—in so-called comagnetometers—boosts performance and opens the possibility of detecting exotic spin interactions predicted in theories that go beyond the standard model of particle physics (see Viewpoint: Spin Gyroscope is Ready to Look for New Physics). Now a new design using a pulsed laser rather than a continuous-laser beam has the potential to improve performance even further [1].

Atomic magnetometry requires two light beams: a pump beam that aligns the atomic spins in a certain direction and a probe beam that detects the movement of those spins relative to that alignment direction. With a single species of atoms, one can measure the local magnetic field. With two species of atoms, one can cancel the magnetic-field signal and other background effects and search for possible spin-dependent signals from dark matter or from other hypothetical particles.

Jingyao Wang from Princeton University and her colleagues have developed a comagnetometer based on a bell-shaped vapor cell filled with rubidium and neon atoms. By applying their pump laser in a repeating pulse pattern (on for 6 ms, off for 20 ms), the researchers can make spin measurements “in the dark” and avoid the noise of the laser. With further improvements, the team predicts its comagnetometer will be 4 times more sensitive than current continuous-laser comagnetometers to potential signals from axions or from other hypothetical particles.

Humans are the only species on Earth known to use language. They do this by combining sounds into words and words into sentences, creating infinite meanings.

This process is based on linguistic rules that define how the meaning of calls is understood in different sentence structures. For example, the word “ape” can be combined with other words to form compositional sentences that add meaning: “the ape eats” or append meaning: “big ape,” and non-compositional idiomatic sentences that create a completely new meaning: “go ape.”

A key component of language is syntax, which determines how the order of words affects meaning. For instance, how “go ape” and “ape goes” convey different meanings.

A way to greatly enhance the efficiency of a method for correcting errors in quantum computers has been realized by theoretical physicists at RIKEN. This advance could help to develop larger, more reliable quantum computers based on light.

Quantum computers are looming large on the horizon, promising to revolutionize computing within the next decade or so.

“Quantum computers have the potential to solve problems beyond the capabilities of today’s most powerful supercomputers,” notes Franco Nori of the RIKEN Center for Quantum Computing (RQC).

New research from a team of cognitive scientists and evolutionary biologists finds that chimpanzees drum rhythmically, using regular spacing between drum hits. Their results, published in Current Biology, show that eastern and western chimpanzees—two distinct subspecies—drum with distinguishable rhythms.

The researchers say these findings suggest that the building blocks of human musicality arose in a common ancestor of chimpanzees and humans.

“Based on our previous work, we expected that western chimpanzees would use more hits and drum more quickly than eastern chimpanzees,” says lead author Vesta Eleuteri of the University of Vienna, Austria. “But we didn’t expect to see such clear differences in or to find that their drumming rhythms shared such clear similarities with human .”

From the powdered wings of a butterfly to the icy spines of a snowflake, symmetry is a common feature in nature. This often even holds true down to the smallest bits of matter, which helps nuclear physicists ensure their measurements of the inhabitants of the subatomic world are accurate. The trick is knowing when something you’re measuring is symmetric and when it is not.

Now, conducting experiments at the U.S. Department of Energy’s Thomas Jefferson National Accelerator Facility have found new and unexpected cases of broken isospin . The discovery upends thoughts on how some particles are produced in experiments and could have implications for future studies of these particles.

The research is published in the journal Physics Letters B.

During that meeting, three main black hole models were outlined: the standard black hole predicted by classical general relativity, with both a singularity and an event horizon; the regular black hole, which eliminates the singularity but retains the horizon; and the black hole mimicker, which reproduces the external features of a black hole but has neither a singularity nor an event horizon.

The paper also describes how regular black holes and mimickers might form, how they could possibly transform into one another, and, most importantly, what kind of observational tests might one day distinguish them from standard black holes.

While the observations collected so far have been groundbreaking, they don’t tell us everything. Since 2015, we’ve detected gravitational waves from black hole mergers and obtained images of the shadows of two black holes: M87* and Sagittarius A*. But these observations focus only on the outside — they provide no insight into whether a singularity lies at the center.