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Ludmila Viotti at the Abdus Salam International Centre for Theoretical Physics in Italy and her colleagues have now shown that some time crystals could be a good building block for very accurate quantum clocks.

They mathematically analysed a system of up to 100 quantum mechanical particles, each of which had two distinct states determined by the property of quantum spin, similar to how a coin on a table has two distinct states determined by which side is facing up. The specific spin system that the researchers studied could become a time crystal or exist in a more conventional phase that didn’t spontaneously oscillate in time, and it could be used as a clock in either phase. The team calculated how the performance of the clock made from spins – its accuracy and precision – in the time crystal phase would compare with a clock made from spins in this “normal” phase.

“In the normal phase, if you want to resolve smaller intervals of time, you will lose accuracy exponentially. In the time crystalline phase, for the same resolution, you can get much higher accuracy,” says Viotti. Although the spin-based clock would normally become less accurate if you wanted to, for example, measure seconds rather than minutes, this didn’t happen if the spins formed a time crystal first.

Mark Mitchison at King’s College London says it isn’t surprising that a time crystal would be a promising starting point for making a clock, but a rigorous analysis of that advantage was missing until now. He and his colleagues previously proved that nearly any random sequence of events can be turned into a clock, but a system that has self-sustained oscillations provides a more clock-like structure from the start, he says.

“For about 10 years, we have known that time crystals can exist, but it is still unclear how to exploit them,” says Krzysztof Sacha at the Jagiellonian University in Poland. “Just as ordinary crystals can be used both for jewellery and for building computer processors, we would like time crystals to enable useful technologies as well.”

Time crystals are unlikely to overtake the current best clocks in the world, which are made from extremely cold atoms, he says, but they could still be an alternative to timekeeping based on satellite systems such as GPS, which can be disrupted by nefarious actors. Clocks built from time crystals could also become the basis of sensors for magnetic fields, since even tiny amounts of such fields would disturb the clocks’ ticks, says Mitchison.

Yet, a lot more work remains before time crystals can be used practically, says Viotti. For instance, her team’s spin system ought to be compared with other systems that behave as accurate clocks and tested in an experiment with actual spins, she says. %!s()

The force of friction opposes motion, dissipates energy and exists everywhere around us, enabling us to walk without slipping, for instance, and to light matches. Within machines such as engines, friction wastes energy and causes wear, so it must be fought with lubricants and surface engineering. Yet, some friction can persist regardless of those methods because objects are full of electrons, which interact with each other.

Now, Zhiping Xu at Tsinghua University in China and his colleagues have devised a way to control this “electronic friction”. They made a device composed of two layers: a piece of graphite and a semiconductor made from either molybdenum and sulphur or from boron and nitrogen.

All three materials are good solid lubricants, which means that mechanical friction from them sliding against each other was nearly zero. This enabled the researchers to focus on the more “hidden” mechanism of electronic friction wasting energy when the device’s layers moved, says Xu. “Even when surfaces slide perfectly, mechanical motion can still stir up the ‘sea’ of electrons within the materials,” he says.

The researchers first studied how electronic states in the semiconductor layer corresponded to how energy was lost during sliding to confirm that they were really looking at electronic friction. Then, they tested several ways of controlling it.

They managed to fully turn it off by adding pressure to the device, which made electrons between the layers share states instead of interacting in energetically costly ways, and by adding a “bias voltage” to the device, which controlled how stirred-up the electron sea could get.

Changing the voltage along two different parts of the device, which affected how easy it was for electrons to flow within it, allowed the researchers to weaken electronic friction – it served as a control dial rather than an on-off switch.

Jacqueline Krim at North Carolina State University says the first studies of electronic friction date to 1998, when her team used a material that conducts electricity perfectly at extremely low temperatures – a superconductor – to see it disappear in this special state. Ever since, researchers have been developing new ways to control it without having to fully switch out materials or add new lubricants into their devices, she says.

Krim says the ideal situation would be analogous to using a smartphone app to adjust the friction of the soles of your shoes as you walk, for example, from an icy sidewalk into a carpeted room. “The goal is this real-time remote control with no down time or material waste. To achieve this, one needs a material that responds to external fields in a way that yields the desired friction level,” she says.

Xu says managing all types of friction present in a device is difficult, in part, because researchers have not yet developed a mathematical model that would rigorously relate all of them to each other. However, in cases where electronic friction is the dominant cause of energy waste or wear, his team’s findings could already be promising, he says. %!s()

UK Research and Innovation (UKRI) is a public body that funds science and business, under the control of the Department for Science, Innovation and Technology. It has announced a budget of £38.6 billion over the next four years, which it claims is actually a slight rise, though this doesn’t factor in inflation. But it has also warned that physics research is due for significant cuts.

UKRI spending is intended to further scientific research but also generate a return for the country. The organisation’s chief executive, Ian Chapman, said in a press briefing on 5 February that the organisation was now focusing more on commercialisation. “We’re a public body, in service of the UK public. The public should expect us to make those hard choices to make sure we make the biggest impact to the country, to grow our economy,” he said.

The organisation distributes grants through nine councils, one of which – the Science and Technology Facilities Council (STFC) – focuses on particle physics, nuclear physics and astronomy. This includes the budget for the UK’s contributions to CERN and the European Space Agency. It is STFC that faces the bulk of the cuts, at a reported £162 million.

Recipients of STFC funding have been told by the body to expect cuts of 30 per cent overall, but were asked to draft different budgets with cuts of 20 per cent, 40 per cent and 60 per cent, according to the Institute of Physics (IOP), which called the news a “devastating blow for the foundations of UK physics”.

IOP president-elect Paul Howarth said in a statement that the cuts would harm “human understanding of the universe and human progress”. “The Large Hadron Collider alone has informed our fundamental understanding of the universe and the matter it is made of. Accelerators developed for particle physics are used in X-ray facilities and new cancer treatments,” he said. “This cut in UK funding will hold up advances in its experimental capability, which will mean less innovation and ultimately less economic growth. We urge the government to step back and consider how its new funding strategy will impact UK science.”

Michele Dougherty, executive chair of STFC, said in a briefing that the organisation had been too ambitious about what it wanted to achieve in previous years. “We’re spread much too thinly, we’re trying to do too many things,” she said. “We’ve got a difficult couple of years in front of us. We simply don’t have the money to do everything.”

Dougherty admitted in the briefing that international collaborations on particle physics were coming to an end and that hard choices were being made. “I think it’s a message that our international partners understand. They too are under financial constraints,” she said.

John Ellis at King’s College London says the cuts tarnish the UK’s reputation among international scientific collaborators. “That’s not the way forwards for international collaboration, and it risks labelling the UK as an unreliable partner,” he says. “People are going to say, ‘Well, look, how do we know that Perfidious Albion is actually going to do what it says it’s going to do?'”

An LHC experiment known as LHCb, which is investigating differences between matter and antimatter, will have its budget cut to zero, says Ellis, which jeopardises plans to upgrade the detectors. Reports suggest that the US-led Electron-Ion Collider, being built at the Brookhaven National Laboratory in New York state, is another affected project.

“International partnerships are crucial for research and innovation, and UKRI remains committed to our existing international obligations – including as the second largest international contributor to CERN,” said a statement issued by UKRI. “Following the spending review that gave UKRI a record four-year settlement to deliver a new mission, UKRI is reforming to align with national priorities. At the same time curiosity driven research will continue to make up around 50% of our funding.” It added that a decision about future infrastructure projects being funded will be announced shortly.

Ellis says the wider cuts to physics research could have long-term implications for the UK, as postdoctoral and junior researcher positions will be lost. “What you risk doing is cutting a whole generation of our young researchers off at the knees,” he says. “It’s not going to be a minor effect.”

Jim Al-Khalili at the University of Surrey, UK, warned that the impact of the cuts would reduce the knowledge, skill and experience available to run the country’s nuclear industry, as well as affect general research. “These proposed cuts are going to be devastating for our community,” he says. “If this goes through, the impact on the core programme will be catastrophic.”

Alicia Greated at the Campaign for Science and Engineering, which represents UK research bodies, says UKRI has made mistakes in how it communicated the cuts, which led to significant confusion and uncertainty. “Regardless of the rationale behind the decision to make savings in the STFC budget, which we do need further clarity on, the impact is the same,” she says. “STFC facilities support all research in the UK, not just that in the physical sciences. Less money for them could undermine a critical part of our research infrastructure.”

Article amended on 9 February 2026

We removed inaccurate details about projects and groups being affected and added a statement from UKRI. %!s()

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Quantum computers may eventually harness quantum phenomena to complete calculations that are intractable for the world’s best conventional computers. Similarly, a simulator harnessing quantum phenomena could help researchers to accurately model poorly understood materials or molecules.

This is especially true for materials such as superconductors, which conduct electricity with nearly perfect efficiency, because they derive this property from quantum effects that could be directly implemented on quantum simulators but would require more steps of mathematical translation on conventional devices.

Michelle Simmons at Silicon Quantum Computing in Australia and her colleagues have now created the biggest quantum simulator for quantum materials yet, called Quantum Twins. “The scale and controllability we have achieved with these simulators means we are now poised to tackle some very interesting problems,” she says. “We are designing new materials in previously unthought-of ways by literally building their analogues atom by atom.”

The researchers built several simulators by embedding atoms of phosphorus into silicon chips. Each atom became a quantum bit, or qubit, which is the basic building block of quantum computers and simulators, and the team could precisely arrange the qubits into different grids that emulated atoms’ arrangement in real materials. Each iteration of Quantum Twins was made up of a square grid of 15,000 qubits – more than any previous quantum simulator. Similar qubit arrays have previously been created from, for example, several thousands of extremely cold atoms.

Through this patterning process and by adding electronic components to each chip, the researchers also controlled properties of electrons in the chip. This mimicked controlling electrons in simulated materials, which is crucial for understanding, for instance, the flow of electricity within them. For example, the researchers could tune how difficult it would be to add an electron to any point in the grid or how difficult it would be for an electron to “hop” between two points.

Simmons says conventional computers struggle with simulating large two-dimensional systems, as well as certain combinations of electrons’ properties, but Quantum Twins simulators have shown promise for those cases. She and her team tested their chips by simulating a transition between metallic (or conducting) and insulating behaviour of a famous mathematical model for how “dirt” in a material can affect its ability to support electric currents. They also measured the system’s “Hall coefficient” as a function of temperature, which captures how the simulated material behaves when exposed to magnetic fields.

The size of the devices used in the experiment and the team’s ability to control variables mean Quantum Twins simulators could go on to tackle unconventional superconductors next, says Simmons. How conventional superconductors work at the level of their electrons is relatively well understood, but they must be made extremely cold or put under tremendous pressure to superconduct, which is impractical. Some superconductors can work in milder conditions, but to engineer them to function at room temperature and pressure, researchers need to understand them more microscopically – the kind of understanding that quantum simulators could offer in the future.

Additionally, Quantum Twins could be used to study interfaces between different metals and molecules similar to polyacetylene that could be useful for drug development or artificial photosynthesis devices, says Simmons. %!s()