Spin-out: Delta.g

Quantum gravity is a branch of physics that seeks to explain some of the most complex environments in the universe, such as the space around black holes and the aftermath of the Big Bang, through the most fundamental forces of nature. 

Delta.g is translating that theory into practice much closer to home. The company is building quantum gravity gradiometers that transform tiny variations in gravity into actionable insights for resilience and navigation applications beneath the Earth’s surface.

Delta.g’s sensors detect the smallest changes in gravity, measured in microgals. A major challenge for sensors is noise, which both mechanical and quantum gravity sensors have traditionally struggled to filter out. This means gravity readings have been useful but limited, as they required post-processing to remove the noise and could only be analysed after the fact. “We eliminate the noise, so we can provide real-time gravity data,” says Tony Lowe, CEO at Delta.g. “Industry has confirmed to us that this is the best kind of data they can get.”

Delta.g spun out from the University of Birmingham in 2023, following ten years of research and £20 million of public funding through the UK National Quantum Technology Programme for Sensing and Timing. In March 2025, the company reached a milestone by delivering its first next-generation sensor device directly to the UK Department for Transport. The next step is to demonstrate the sensor in a customer environment as a TRL-7 (Technology Readiness Level 7) device. “That’s the stage where we show the real-world value our sensor can provide,” says Mr Lowe. “But it’s not just about building the sensor. We also build the data platform around it. Technology on its own is interesting, but it has to solve a customer problem and deliver customer value.”

For the Department for Transport, the value is clear. The agency has plenty of data about the surface of roads and rail, but very little about what lies beneath, because gathering it requires digging expensive, disruptive holes – this can take up to two weeks in an area of 20 square metres. “We can survey the same area in half a day, identifying voids, subsidence, or changes in ground conditions that could cause instability,” says Mr Lowe. “We go beyond what the eye can see and provide data faster.”

Recently, recognising the need to present itself as a commercial business to raise money and scale, Delta.g relocated to new labs at Birmingham Research Park with support from Enterprise. Since spinning out, they brought in a new CEO and secured investment from both government contracts and venture capital, and are building traction with major firms across telecoms and mining. Mr Lowe highlights the critical role of the Enterprise team in this process. 

The company also takes pride in representing its region, with initiatives like the Midlands Engine looking to establish the Midlands as a leader in deep tech. “We're building a UK-wide ecosystem, instead of just focusing on London and the Golden Triangle,” says Mr Lowe. The presence of the UK Quantum Technology Hub in Sensing, Imaging and Timing in Birmingham was critical to Delta.g’s formation, as was the government’s National Quantum Strategy Missions initiative. Recognition such as the Institute of Physics qBIG Prize, which Delta.g won, aims to support commercialisation and keep the UK at the forefront of quantum sensing. “We often hear that quantum computing is still 15 years away,” says Mr Lowe. “But there’s so much technology that can be packaged and used in the very near term to deliver real value across multiple industries.”

The company is working toward a more advanced technology readiness scale (TRL)-9 device, which would be fully deployable, maintainable, and upgradable throughout its lifecycle. “Customers need to be able to order it, use it, return it, and fix it,” says Mr Lowe. “That’s the level we’re focusing on: moving from the lab to the real world, proving value, and scaling.”

And the potential applications stretch even further. “We’re thinking way beyond the existing geophysical market: applying it to drones, autonomous vehicles, trains, and ships,” says Mr Lowe. “Gravity is a fundamental force of nature, but it is thoroughly underutilised today.”