Hi Reader, last week NASA released a video of its X-59 jet flying at near-supersonic speed. Crucially, it’s flying at that speed without the window-rattling boom that grounded supersonic flight over land after the Concorde era. The agency is now flying over communities to find out whether the public will finally accept it. If they do, a technology the world shelved 50 years ago could make a comeback. This week’s top stories keep up this spirit, testing ideas that have stood for decades, and in some cases, centuries.

Coming up:
​⚛️ CERN finds something a 50-year-old theory can’t explain
🩻 The invisible structure behind ultrasound, finally revealed
🍏 Newton's 340-year-old gravity law, tested
+ More

PARTICLE PHYSICS

CERN Found Something Physics Can't Explain

William Barter and Mark Smith have spent years sifting through the wreckage of particle collisions, hunting for something that shouldn't exist. The two physicists are part of the LHCb collaboration at CERN, and they've been on the hunt for what's known as an electroweak penguin decay: a B meson dissolving into four other particles in a process so rare it happens only once in every million decays.

To catch enough of them, the team worked through 650 billion B mesons, gathered over seven years inside the LHCb detector. What emerged from that analysis, now accepted in Physical Review Letters, is making physicists sit up. The angles and energies at which the decay products scatter, and the rate at which the decay occurs, both diverge from what the Standard Model predicts. The discrepancy sits at 4-sigma: roughly a 1-in-16,000 chance of being statistical noise. A second independent detector flagged the same anomaly last year.

The Standard Model, the scientists write, "is our best understanding of fundamental particles and forces, but we know it cannot be the whole story." After 50 years without a crack, they suggest they "might be closing in on signs of undiscovered physics."

For now, the Standard Model isn't cracked yet. 5-sigma is the gold standard for a discovery, and a thorny theoretical wrinkle called "charming penguins" (internal processes involving charm quarks) makes precise calculations difficult. But current estimates suggest those effects aren't large enough to explain what's being seen.

If the anomaly survives, it would demand something new: perhaps a Z′ boson carrying an undiscovered force, or leptoquarks (exotic particles that blur the boundary between quarks and leptons). The team already has three times more data waiting to be analysed. As Barter and Smith put it, the coming years should "allow definitive claims to be made."

TL;DR: The LHCb experiment at CERN has found a 4-sigma deviation from Standard Model predictions in rare B meson "penguin" decays - a 1-in-16,000 chance of being a fluke, corroborated by a second independent detector. If confirmed at 5-sigma, it would signal the first crack in particle physics' 50-year-old theoretical bedrock, potentially pointing to an undiscovered force or new exotic particles.

MATERIAL SCIENCE

The Invisible Structure Behind Medical Ultrasound, Revealed

Menglin Zhu and Michael Xu pressed an electron beam, nanometres wide, across a sliver of crystal. For the first time in the history of materials science, the MIT scientists watched a three-dimensional map of its atomic structure emerge.

The material being studied was a relaxor ferroelectric: a class of crystals so sensitive to electric fields that they underpin medical ultrasound, submarine sonar, and some of the most precise sensors ever built. For decades, engineers have tuned and deployed them without fully understanding why they work. The atomic structure was too disordered, too three-dimensionally complex, for conventional imaging to resolve.

The team’s results, published in Science, reveal the hidden structure behind this class of widely used materials. To do so, they used a technique called multi-slice electron ptychography. By scanning a focused beam of electrons across the material and collecting the scattered diffraction patterns at each point, their algorithm stitched overlapping measurements into a full 3D volumetric reconstruction atom by atom and layer by layer.

What they found surprised them. The internal polar regions (nanoscale zones where electric dipoles align, long theorized to give relaxors their exceptional properties) were smaller and more chemically entangled than the best existing simulations had assumed. The team could directly compare their experimental 3D map with molecular dynamics simulations, revealing exactly where and why the models were wrong.

This discovery could matter enormously for the next generation of devices. Better models mean better-designed materials: more sensitive medical scanners, more efficient energy harvesters, and potentially new applications in neuromorphic computing.

TL;DR: Researchers have mapped the 3D atomic structure of relaxor ferroelectrics for the first time, using multi-slice electron ptychography. The material (which powers ultrasound, sonar, and precision sensors) turned out to have smaller, more complex internal polar regions than leading models predicted, giving engineers a corrected blueprint to design the next generation of sensing, energy, and computing devices.

COSMOLOGY

Newton's 340-Year-Old Law Just Passed Its Biggest Test

In 1687, Isaac Newton published his law of universal gravitation: the force between two objects weakens with the square of the distance between them. This single equation shifted our understanding of physics, explained the motion of the planets, the arc of cannon fire, and the fall of an apple with the same elegant mathematics.

Three hundred and forty years later, Patricio Gallardo is testing it.

The University of Pennsylvania cosmologist has spent his career staring at a number that doesn't add up. "Astrophysics has been plagued by a massive discrepancy in the cosmic ledger," he says. “When we look at how stars orbit within galaxies or how galaxies move within galaxy clusters, some appear to be traveling way too fast for the amount of visible matter they contain.”

Either the universe is threaded with vast quantities of invisible "dark matter" providing the extra gravitational pull, or Newton's law itself breaks down at large scales (an idea formalised as Modified Newtonian Dynamics or MOND).

Neither of these ideas has been proven. Using data from the Atacama Cosmology Telescope - a now-decommissioned multi-storey instrument that observed the Chilean desert sky - and the positions of 686,000 galaxies from the Sloan Digital Sky Survey, Gallardo's team tracked how pairs of galaxy clusters pull toward each other across distances of up to 750 million light-years, using the faint imprint their motion leaves on ancient light passing through them. Each cluster contains hundreds of galaxies and outweighs the Sun by a quadrillion times. The distances involved were, as Gallardo puts it, "inconceivable in Newton's day."

The answer, published in Physical Review Letters, shows that gravity scales as 1/r^(2.1 ± 0.3). In words: Newton's inverse-square law holds across the largest distances it has ever been tested. MOND fits the data poorly. Dark matter survives as the more compelling explanation for the cosmic ledger's missing entries.

"It is remarkable," Gallardo says, "that the law of the inverse of the squares - proposed by Newton in the 17th century and then incorporated by Einstein's theory of general relativity - is still holding its ground in the 21st century."

TL;DR: Cosmologists used the Atacama Cosmology Telescope to test Newton's inverse-square law across up to 800 million light-years - the largest-scale test of gravity ever conducted. Gravity behaves exactly as Newton and Einstein predicted, dealing a significant blow to Modified Newtonian Dynamics and strengthening the case that invisible dark matter is real.

News

MIT startup develops process to recover critical metals from industrial waste. Found Industries developed an electrochemical process that recovers gallium - a semiconductor-critical metal 98% controlled by China - directly from aluminium refinery waste streams. Backed by a DOE programme, their new Found Metals division aims to restart US domestic gallium production by 2027 for the first time since 1987, targeting a critical gap in American supply chains.

How does Uranus form its rings? Uranus has two ghostly outer rings (one blue, one red) and nobody knew where they came from. Now, using JWST, Hubble, and Keck, astronomers have traced the blue ring to a moon the size of a small city, pulverised by micrometeorites. The red ring points to moons we haven't found yet.

SpaceX rocket on course to crash into the Moon. A stray Falcon 9 upper stage that was supposed to burn up in Earth’s atmosphere is now on a collision course with the Moon, expected to hit on August 5 at ~5,400 mph. Its path isn’t perfectly predictable due to the effect of sunlight, whose photon pressure has nudged the rocket just enough to complicate the math. It is one of the most closely tracked cases of space junk hitting the Moon, adding to growing concerns about lunar debris.

Making Pluto a planet again. In 2006, Pluto lost its planet status and was reclassified as a dwarf planet. Recently, NASA administrator Jared Isaacman declared he supports restoring Pluto's planetary status and that the agency is preparing position papers to push for the debate to be reopened within the scientific community. This has revived the debate: some researchers call it a distraction and accept the 2006 ruling, while others maintain Pluto's status is still genuinely unsettled.

The bizarre state of matter hiding inside Uranus and Neptune. Deep inside Uranus and Neptune, pressures millions of times greater than Earth's atmosphere crush matter into states that shouldn't exist. Quantum simulations by Carnegie scientists now predict one such state: a carbon-hydrogen compound where carbon locks into a rigid lattice and hydrogen spirals through it like a corkscrew. It is half solid, half liquid and potentially the reason both planets have such strangely lopsided magnetic fields.

We found the edge of the Milky Way. No one knows where our galaxy ends. Now astronomers have found its edge by reading the ages of 100,000 stars. At around 40,000 light-years from the galactic centre, star birth appears to stop. Beyond that, every star you see is a migrant: born elsewhere, drifted outward, slowly fading into the dark. The cutoff may result from disrupted gas flows, a warped disk, or simply gas too thin for star birth, marking the edge of the Milky Way's "productive zone."

Physicists just measured a negative amount of time. Shoot a photon through a cloud of atoms, and sometimes it arrives as if it spent less than no time inside. Physicists published evidence of a negative quantum dwell time: the duration a photon's energy spends exciting atoms in a rubidium cloud. The result reflects quantum interference effects (rather than time-travel-esque ideas!), showing that measurable durations in quantum systems can fall below zero.

This Week in History

May 5, 1834. William Whewell coined the terms "anode," "cathode," and "ion", proposing them in a letter to Michael Faraday to describe the process of electrolysis. Derived from Greek, the words reflected the then-prevailing idea that current flowed downhill from positive to negative. Faraday accepted immediately, writing he was "delighted with the facility of expression which the new terms give me."

May 3, 1933. Steven Weinberg was born. He revealed that two seemingly different forces, electromagnetism and the weak force, are actually one, unified under electroweak theory. That insight became a cornerstone of the Standard Model. He also made foundational contributions to our understanding of the early universe and helped shape modern cosmology, while his textbooks and essays clarified some of physics’ most complex ideas for generations of scientists.

May 1, 1958. James Van Allen discovered Earth's radiation belts, using data from the Explorer 1 and Pioneer 3 satellites. The two donut-shaped zones of magnetically trapped, charged particles encircling our planet were the first major scientific discovery of the Space Age and later proved critical to planning safe routes for crewed missions to the Moon.

This Week’s Puzzle

🧩

THE ODD BALL

You have 12 balls. They look identical. But one is either heavier or lighter than the rest. You don't know which, and you don't know which way.

Your only tool: a balance scale.

The catch: you can only use it three times.

How would you identify the odd ball and determine whether it's heavier or lighter?

Until next time,

The Ve Team 👋

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Research by Pablo
Written by Ines

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Solution

The key is to realize that the scale gives you three outcomes each time: left heavy, right heavy, or balanced. Over three weighings, that's 3³ = 27 possible combinations of results. You only need to distinguish 24 scenarios (12 balls, each either heavier or lighter).

Number the balls 1, 2, 3, ... 10, 11, 12

Start off with them in 3 groups: [1, 2, 3 and 4], [5, 6, 7 and 8] and [9,10,11 and 12]

Weigh 1, 2, 3 and 4 vs 5, 6, 7 and 8 with 3 possible outcomes:

(1) If they balance then 9,10,11,12 have the odd ball, so weigh 6,7,8 vs 9,10,11 with 3 possible outcomes:

(1a) If 6,7,8 vs 9,10,11 balances, 12 is the odd ball. Weigh it against any other ball to determine if heavy or light.

(1b) If 9,10,11 is heavy then they contain a heavy ball. Weigh 9 vs 10, if balanced then 11 is the odd heavy ball, else the heavier of 9 or 10 is the odd heavy ball.

(1c) If 9,10,11 is light then they contain a light ball. Weigh 9 vs 10, if balanced then 11 is the odd light ball, else the lighter of 9 or 10 is the odd light ball.

(2) If 5,6,7,8 > 1,2,3,4 then either 5,6,7,8 contains a heavy ball or 1,2,3,4 contains a light ball so weigh 1,2,5 vs 3,6,12 with 3 possible outcomes:

(2a) If 1,2,5 vs 3,6,12 balances, then either 4 is the odd light ball or 7 or 8 is the odd heavy ball. Weigh 7 vs 8, if they balance then 4 is the odd light ball, or the heaviest of 7 vs 8 is the odd heavy ball.

(2b) If 3,6,12 is heavy then either 6 is the odd heavy ball or 1 or 2 is the odd light ball. Weigh 1 vs 2, if balanced then 6 is the odd heavy ball, or the lightest of 1 vs 2 is the odd light ball.

(2c) If 3,6,12 is light then either 3 is light or 5 is heavy. Weigh 3 against any other ball, if balanced then 5 is the odd heavy ball else 3 is the odd light ball.

(3) If 1,2,3,4 > 5,6,7,8 then either 1,2,3,4 contains a heavy ball or 5,6,7,8 contains a light ball so weigh 5,6,1 vs 7,2,12 with 3 possible outcomes:

(3a) If 5,6,1 vs 7,2,12 balances, then either 8 is the odd light ball or 3 or 4 is the odd heavy ball. Weigh 3 vs 4, if they balance then 8 is the odd light ball, or the heaviest of 3 vs 4 is the odd heavy ball.

(3b) If 7,2,12 is heavy then either 2 is the odd heavy ball or 5 or 6 is the odd light ball. Weigh 5 vs 6, if balanced then 2 is the odd heavy ball, or the lightest of 5 vs 6 is the odd light ball.

(3c) If 7,2,12 is light then either 7 is light or 1 is heavy. Weigh 7 against any other ball, if balanced then 1 is the odd heavy ball else 7 is the odd light ball.