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Mysterious ‘red dots’ in early universe may be ’black hole star‘ atmospheres
Tiny red objects spotted by NASA’s James Webb Space Telescope (JWST) are offering scientists new insights into the origins of galaxies in the universe—and may represent an entirely new class of celestial object: a black hole swallowing massive amounts of matter and spitting out light.
Using the first datasets released by the telescope in 2022, an international team of scientists including Penn State researchers discovered mysterious “little red dots.” The researchers suggested the objects may be galaxies that were as mature as our current Milky Way, which is roughly 13.6 billion years old, just 500 to 700 million years after the Big Bang.
Informally dubbed “universe breakers” by the team, the objects were originally thought to be galaxies far older than anyone expected in the infant universe—calling into question what scientists previously understood about galaxy formation.
Measuring the quantum W state: Seeing a trio of entangled photons in one go
The concept of quantum entanglement is emblematic of the gap between classical and quantum physics. Referring to a situation in which it is impossible to describe the physics of each photon separately, this key characteristic of quantum mechanics defies the classical expectation that each particle should have a reality of its own, which gravely concerned Einstein.
Understanding the potential of this concept is essential for the realization of powerful new quantum technologies.
Developing such technologies will require the ability to freely generate a multi–photon quantum entangled state, and then to efficiently identify what kind of entangled state is present. However, when performing conventional quantum tomography, a method commonly used for state estimation, the number of measurements required grows exponentially with the number of photons, posing a significant data collection problem.
New study links blood proteins to Alzheimer’s disease and memory loss
Researchers at Emory Goizueta Brain Health Institute and partner institutions have found new clues in the blood that could help explain why Alzheimer’s disease develops and how it affects memory.
The study, published in Nature Aging, examined blood samples from more than 2,100 individuals across four large research cohorts. Using advanced tools, scientists measured thousands of proteins in the blood and linked them to changes in the brain and thinking ability.
Traditionally, doctors have focused on sticky amyloid plaques in the brain as a hallmark of Alzheimer’s.
Genetic deletion in cerebellum impedes hemisphere formation, study finds
The cerebellum, a brain region located at the back of the head that has long been known to support the coordination of muscle movements, has recently also been implicated in more sophisticated mental functions. Purkinje cells are the only neurons located in the cerebellum that integrate information in the cerebellar cortex and send it to other parts of the nervous system.
Purkinje cells are large and highly branched nerve cells that can have different functions. While many past studies have explored the roles of these cells, the neural and genetic processes shaping their diversity have not yet been fully elucidated.
Researchers at the University of Connecticut School of Medicine recently carried out a study aimed at exploring the possible role of the FOXP genes, a family of genes known to contribute to switching other genes “on and off,” in shaping Purkinje cell populations and the formation of circuits in the cerebellum. Their findings, published in Nature Neuroscience, hint at the existence of at least 11 different Purkinje cell subtypes, suggesting that the FOXP1 and FOXP2 genes contribute to their diversification.
Trilayer moiré superlattices unlock tunable control of exciton configurations
Moiré superlattices are periodic patterns formed when two or more thin semiconducting layers are stacked with a small twist angle or lattice mismatch. When 2D materials form these patterns, their electronic, mechanical, and optical properties can change significantly.
Over the past decades, moiré superlattices have emerged as a promising platform to study unconventional and unknown physical states. They also enabled the observation of unique excitonic configurations (i.e., arrangements of bound electron-hole pairs).
In bilayer moiré systems based on two-dimensional transition metal dichalcogenides (TMDCs), for instance, physicists have observed interlayer dipolar excitons. These are excitons produced when an electron and a hole are bound together across different layers in a stacked 2D semiconductor.
New quantum sensors can withstand extreme pressure
The world of quantum physics is already mysterious, but what happens when that strange realm of subatomic particles is put under immense pressure? Observing quantum effects under pressure has proven difficult for a simple reason: Designing sensors that can withstand extreme forces is challenging.
In a significant advance, a team led by physicists at WashU has created quantum sensors in an unbreakable sheet of crystallized boron nitride. The sensors can measure stress and magnetism in materials under pressure that exceeds 30,000 times the pressure of the atmosphere.
“We’re the first ones to develop this sort of high-pressure sensor,” said Chong Zu, an assistant professor of physics in Arts & Sciences and a member of Washington University in St. Louis’ Center for Quantum Leaps. “It could have a wide range of applications in fields ranging from quantum technology, material science, to astronomy and geology.”
Soft magnetoelastic sensor measures fatigue from eyeball movements in real-time
Over the past few decades, electronics engineers have developed increasingly sophisticated sensors that can reliably measure a wide range of physiological signals, including heart rate, blood pressure, respiration rate and oxygen saturation. These sensors were used to create both biomedical and consumer-facing wearable devices, advancing research and the real-time monitoring of health-related metrics, such as sleep quality and physiological stress.
Fatigue, a mental state marked by a decline in performance due to stress, lack of sleep, excessive activity or other factors, has proved to be more difficult to reliably quantify. Most existing methods for measuring fatigue rely on surveys that ask people to report how tired they feel, a method to record the brain’s electrical activity known as electroencephalography (EEG) or camera-based systems.
Most of these approaches are unreliable or only applicable in laboratory settings, as they rely on subjective evaluations, bulky equipment or controlled environments. These limitations prevent their large-scale deployment in everyday settings.
Ultra-flat optic pushes beyond what was previously thought possible
Cameras are everywhere. For over two centuries, these devices have grown increasingly popular and proven to be so useful, they have become an indispensable part of modern life.
Today, they are included in a vast range of applications—everything from smartphones and laptops to security and surveillance systems to cars, aircraft, and satellites imaging Earth from high above. And as an overarching trend toward miniaturizing mechanical, optical, and electronic products continues, scientists and engineers are looking for ways to create smaller, lighter, and more energy-efficient cameras for these technologies.
Ultra-flat optics have been proposed as a solution for this engineering challenge, as they are an alternative to the relatively bulky lenses found in cameras today. Instead of using a curved lens made out of glass or plastic, many ultra-flat optics, such as metalenses, use a thin, flat plane of microscopic nanostructures to manipulate light, which makes them hundreds or even thousands of times smaller and lighter than conventional camera lenses.
Synthetic magnetic fields steer light on a chip for faster communications
Electrons in a magnetic field can display striking behaviors, from the formation of discrete energy levels to the quantum Hall effect. These discoveries have shaped our understanding of quantum materials and topological phases of matter. Light, however, is made of neutral particles and does not naturally respond to magnetic fields in the same way. This has limited the ability of researchers to reproduce such effects in optical systems, particularly at the high frequencies used in modern communications.
To address this challenge, researchers from Shanghai Jiao Tong University and Sun Yat-Sen University have developed a method for generating pseudomagnetic fields—synthetic fields that mimic the influence of real magnetic fields—inside nanostructured materials known as photonic crystals.
Unlike previous demonstrations, which focused on specific effects such as photonic Landau levels, the new approach allows arbitrary control of how light flows within the material. Their research is published in Advanced Photonics.