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New evidence suggests Einstein’s cosmic constant may be wrong

Dark energy may be evolving—hinting that the universe’s ultimate destiny could be far stranger than we ever imagined. Astronomers are rethinking one of cosmology’s biggest mysteries: dark energy. New findings show that evolving dark energy models, tied to ultra-light axion particles, may better fit the universe’s expansion history than Einstein’s constant model. The results suggest dark energy’s density could be slowly declining, altering the fate of the cosmos and fueling excitement that we may be witnessing the universe’s next great revelation.

Dark energy, the mysterious force thought to drive the universe’s accelerating expansion, remains one of the deepest puzzles in modern physics. For years, the leading explanation has been that this energy is constant – an unchanging property of empty space responsible for cosmic acceleration. But recent evidence has scientists rethinking that assumption.

Last year, results from the Dark Energy Survey (DES) and the Dark Energy Spectroscopic Instrument (DESI) caught the attention of cosmologists by suggesting that dark energy might not be fixed after all. “This would be our first indication that dark energy is not the cosmological constant introduced by Einstein over 100 years ago but a new, dynamical phenomenon,” explained Josh Frieman, Professor Emeritus of Astronomy and Astrophysics.

A Quantum Microscope Reveals Water Breaking Apart

A scheme combining a scanning probe microscope with a quantum sensor can locally trigger water dissociation and observe the elementary steps of such a reaction.

Every experimental technique comes with trade-offs. High-resolution microscopy can pinpoint the positions of individual atoms, yet it typically cannot identify them chemically. Spectroscopy provides chemical information but often only as an averaged signal over a large region. To construct a comprehensive picture of processes at the nanoscale, researchers often resort to combining two or more independent methods. The metaphorical silver bullet would be a single technique that is both local and capable of identifying chemical species as they form and react. Now Wentian Zheng of Peking University and his collaborators have taken an impressive step toward that goal. They have combined two previously separate capabilities—quantum sensing and scanning probe microscopy (SPM)—into a single instrument that can trigger and observe chemical reactions with nanometer resolution [1].

Iron core-shell catalyst boosts hydrogen economy of direct syngas to olefin conversion

Scientists have developed a new iron-based catalyst that improves the typically low hydrogen atom economy (HAE) in the direct synthesis of olefins—small hydrocarbon molecules. It converts the water produced as a by-product into hydrogen for olefin production, thereby boosting overall efficiency.

Olefins derived from petroleum are the building blocks for many plastics and fuels. Direct conversion of syngas—a mixture of carbon monoxide (CO) and hydrogen (H2)—into olefins offers a promising alternative to reducing reliance on petroleum. It opens ways for using syngas derived from coal, biomass, or as a feedstock for olefin production.

In this study published in Science, researchers presented a sodium-modified FeCx@Fe3O4 core-shell produced via coprecipitation and thermal treatment. The catalyst achieved over 75% olefin selectivity and a 33% by weight hydrocarbon yield. It also had an HAE of ~66–86%, which is significantly higher than the ~43–47% seen in the traditional syngas-to-olefin (STO) conversion methods.

Could mass arise without the Higgs boson?

The geometry of space, where physical laws unfold, may also hold answers to some of the deepest questions in fundamental physics. The very structure of spacetime might underlie every interaction in nature.

A paper published in Nuclear Physics B, led by Richard Pincak, explores the idea that all and particle properties could emerge from the geometry of hidden .

According to the study, the universe may contain invisible dimensions folded into intricate seven-dimensional shapes known as G₂-manifolds. Traditionally, these structures have been studied as static. But Pincak and colleagues consider them as dynamic: evolving under a process called the G₂–Ricci flow, where the internal geometry changes with time.

Turning the faint quantum ‘glow’ of empty space into a measurable flash

Researchers from Stockholm University and the Indian Institute of Science Education and Research (IISER) Mohali have reported a practical way to spot one of physics’ strangest predictions: the Unruh effect, which says that an object speeding up (accelerating) would perceive empty space as faintly warm. But, trying to heat something up by accelerating it unimaginably fast is a nonstarter in the lab. The team has shown how to convert that tiny effect into a clear, timestamped flash of light.

Here’s the simple picture. Imagine a group of atoms between two parallel mirrors. The mirrors can either speed up or slow down light emission from the atoms. When these atoms cooperate, they can emit together like a choir—much louder than solo singers. This collective outburst is called superradiance.

The new study explains how the acceleration-induced warmth of empty space, if experienced by the atoms, quietly nudges them so that the choir’s burst happens earlier than it would for atoms sitting still. That earlier-than-expected flash becomes a clean, easy-to-spot signature of the Unruh effect. The work, co-authored with Kinjalk Lochan and Sandeep K. Goyal of IISER Mohali, is now published in Physical Review Letters.

How plastics grip metals at the atomic scale: Molecular insights pave way for better transportation materials

What makes some plastics stick to metal without any glue? Osaka Metropolitan University scientists have peered into the invisible adhesive zone that forms between certain plastics and metals—one atom at a time—to uncover how chemistry and molecular structure determine whether such bonds bend or break.

Their insights clarify metal–plastic bonding mechanisms and offer guidelines for designing durable, lightweight, and more sustainable hybrid materials for use in transportation.

Combining the strength of metal with the lightness and flexibility of plastic, polymer–metal hybrid structures are emerging as key elements for building lighter, more fuel-efficient vehicles. The technology relies on bonding metals with plastics directly, without adhesives. The success of these hybrids, however, hinges on how well the two materials stick together.

Machine learning automates material analysis and design using X-ray spectroscopy data

Understanding the properties of different materials is an important step in material design. X-ray absorption spectroscopy (XAS) is an important technique for this, as it reveals detailed insights about a material’s composition, structure, and functional characteristics. The technique works by directing a beam of high-energy X-rays at a sample and recording how X-rays of different energy levels are absorbed.

Similar to how splits into a rainbow after passing through a prism, XAS produces a spectrum of X-rays with different energies. This spectrum is called as , which acts like a unique fingerprint of a material, helping scientists to identify the elements present in the material and see how the atoms are arranged. This information, known as the “electronic state,” determines the functional properties of materials.

Boron compounds have significant applications in semiconductors, Internet-of-Things (IoT) devices, and energy storage. In these materials, atomic modifications, structural defects, impurities, and doped elements, each produce unique, complex variations in spectral data. Detailed analyses of these variations provides key insights into their electronic state and is crucial for rational material design. Traditionally, however, such analyses required extensive expertise and manual labor, especially when large datasets have to be examined visually.

Climate intervention may lower protein content in major global food crops

A new study in Environmental Research Letters reports that cooling the planet by injecting sulfur dioxide into the stratosphere, a proposed climate intervention technique, could reduce the nutritional value of the world’s crops.

Scientists at Rutgers University used and crop models to estimate how stratospheric aerosol intervention (SAI), one type of solar geoengineering, would impact the protein level of the world’s four major food crops: maize, rice, wheat, and soybeans. The SAI approach, inspired by volcanic eruptions, would involve releasing into the stratosphere. This gas would transform into sulfuric acid particles, forming a persistent cloud in the upper atmosphere that reflects a small part of the sun’s radiation, thereby cooling Earth.

While these are primarily sources of carbohydrates, they also provide a substantial share of dietary protein for large portions of the global population. Model simulations suggested that increased CO2 concentrations tended to reduce the protein content of all four crops, while increased temperatures tended to increase the protein content of crops. Because SAI would stop temperatures from increasing, the CO2 effect would not be countered by warming, and protein would decrease relative to a warmer world without SAI.

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