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Primordial black holes, or PBHs, are one of the most interesting ideas in modern cosmology. Unlike normal black holes, which can form when massive stars collapse, primordial black holes could have formed in the very early universe, long before stars and galaxies existed. A new study by Li and his team explores an important question: Could heavy fields that existed during cosmic inflation make it much easier for primordial black holes to form? The researchers found that these heavy fields can produce a special type of non-Gaussianity in the early universe. This can increase the number of very large density fluctuations and, as a result, greatly increase the production of primordial black holes. How Are Primordial Black Holes Formed? Soon after the Big Bang, the universe was extremely hot and dense. During a period called cosmic inflation , the universe expanded incredibly quickly. At that time, tiny quantum fluctuations existed throughout space. Inflation stretched these tiny fluctuatio...

Black holes are among the most extreme objects in the universe. They have such strong gravity that nothing can escape once it crosses the event horizon. But some black holes can become even more extreme when they carry a very large electric charge. A recent theoretical discussion by Hod and Piran explores an important question: Can nature actually create an extremely charged black hole, or does physics prevent it from happening? The question is connected to one of the important ideas in black-hole thermodynamics, known as the third law of thermodynamics . Earlier studies suggested that forming an extremal black hole could create a problem for this law. Now, quantum physics may offer a possible solution. What Is an Extremal Black Hole? A Reissner–Nordström black hole is a theoretical black hole that has mass and electric charge but does not rotate. Normally, a black hole has to have enough mass compared with its electric charge. If the charge becomes extremely large compared with the m...

For many years, scientists have used a model called ΛCDM to explain how the Universe has changed over time. It describes a Universe containing normal matter, dark matter and a mysterious component called the cosmological constant, Λ . The cosmological constant is usually connected with dark energy , which is thought to be responsible for the accelerating expansion of the Universe. But there is a major problem. Scientists still do not know what dark energy actually is. The amount of vacuum energy predicted by quantum physics is also very different from the amount needed to explain the Universe. At the same time, measurements of the Universe have revealed disagreements between different observations, especially measurements of the expansion rate known as H₀ , or the Hubble constant. Now, a team led by Lee has tested an unusual idea called thermogravity . Instead of using a cosmological constant or traditional dark energy, the theory asks whether the Universe could accelerate because en...

When scientists search for potentially habitable worlds beyond our Solar System, they often look for rocky planets with atmospheres. Earth is the obvious example: its atmosphere helps regulate temperature and allows liquid water to exist on the surface. But rocky planets with atmospheres appear to be surprisingly difficult to find. Now, astronomers have discovered evidence of an atmosphere around an unusual world that is anything but habitable. Located about 154 light-years away in the constellation Pisces , the planet HD 3167 b is a rocky “lava world” so close to its star that it completes an entire orbit in just one Earth day . What makes it especially interesting is that it is reportedly the coolest lava world yet found with evidence of an atmosphere . The discovery, led by University of Chicago scientist Brandon Park Coy , was published in The Astrophysical Journal Letters . Researchers say this strange, extremely hot planet could help answer a much bigger question: How did rocky ...

Imagine taking just one second and dividing it into trillions of tiny moments—and then measuring those moments with extraordinary precision. That is essentially what scientists at Singapore’s Centre for Quantum Technologies (CQT) have achieved with a new atomic clock. Researchers at CQT and the National University of Singapore have developed a lutetium-based optical atomic clock that they say has achieved the lowest measurement uncertainty ever reported for an optical atomic clock. Their results, published in Nature on September 23, 2026, could help scientists explore fundamental physics, detect tiny changes in gravity and potentially contribute to a future redefinition of the international second. Team leader Murray Barrett, a CQT principal investigator and associate professor of physics at the National University of Singapore, said he is confident that the device is currently the world’s most accurate clock. What makes an atomic clock so accurate? Unlike ordinary clocks, atomic clo...

Rocket launches are one of the most extreme environments humans have created. A spacecraft must survive enormous thrust, powerful vibrations and intense forces before it even begins its mission in space. For satellites carrying delicate cameras, mirrors, sensors and electronics, these vibrations can be especially dangerous. A tiny crack in a sensitive component or a damaged connection during launch could potentially destroy years of engineering work and cost billions of dollars. Now, researchers in Switzerland have developed an unusual technology that could make rocket launches much gentler for satellites—without adding large amounts of weight. Why Rocket Launches Are So Violent When a rocket takes off, its engines produce enormous amounts of thrust to overcome Earth's gravity. This creates strong forces and vibrations throughout the rocket. Astronauts are trained to handle these forces, while spacecraft are carefully engineered to survive them. But satellites can contain extremely...

Silicon has long been viewed as one of the most promising materials for building the next generation of lithium-ion batteries. It can store far more lithium than the graphite used in most commercial battery anodes, potentially allowing batteries to hold much more energy without dramatically increasing their size. But silicon has a major weakness: it expands and contracts dramatically every time a battery is charged and discharged . This repeated movement can damage the material, break electrical connections and destabilize the protective layer around the electrode. Eventually, the battery loses capacity and performance. Now, researchers led by Qiangfeng Xiao have developed a new type of silicon structure designed to solve this problem. Their hierarchically porous silicon nanospheres (hp-SiNSs) contain both a porous outer shell and a hollow interior. Instead of expanding outward like conventional silicon particles, these structures can accommodate lithium by expanding mainly inward . ...