At the cutting-edge of ITS, quantum sensors are being deployed to provide GNSS-free navigation, snoop-proof communications and mapping, while quantum computing is creating a whole new level of efficiency in transportation modeling and routing… but chaos for the unprepared awaits on what is known as Q-Day
Spooky boxes full of magic soup? Well not quite. But Quantum technologies do exploit three very weird things that particles do when they think no one’s looking. Superposition – the ability to be in two states at once, like a spinning coin that’s both heads and tails at once. Then there’s Interference, where particles act like two stones thrown into a lake, the ripples make new patterns. And don’t forget Entanglement, like twins who get goosebumps at the same time. Strange, right? What does it all mean for the world of traffic technology? A lot.
Quantum computing promises to ease congestion and aid autonomous vehicles, quantum sensing can revolutionise road maintenance, and quantum navigation makes precision route-finding in GNSS-denied areas a reality. There’s big money on the table; a DfT report, Potential Socio-Economic Impacts of Quantum Technologies in UK Transport estimates that £8bn (US$10bn) can be gained to the UK economy, the lion’s share in time-critical transport optimization.
2025 was dubbed the International Year of Quantum Science and Technology by the UN, as Heisenberg’s ground-breaking theory celebrates its centenary. But in terms of practical applications it’s still early days. When a quantum computer calculates an equation that would be impossible for a classical computer, it’s called quantum advantage. We’re not there yet, but other applications are ready to go.
Quantum navigators
‘’GPS absolutely rules our daily lives,” says Michael J Biercuk, CEO of Q-CTRL, a pioneering company specializing in quantum technologies. Everything from mobile phone application all the way through to the way airplanes fly. It has, despite its ubiquity, become very vulnerable and we’ve seen with recent flare ups of conflict in the Middle East and in Ukraine, with active GPS denial and spoofing.” GPS has always risked intermittency. It’s absent at high altitudes over the Arctic Circle, and in cities, satellites can easily be occluded by buildings. Underground, no chance. Underwater? Also no.
Today, GPS has become so important to urban and intercity logistics, that a coordinated outage could lead to mass chaos.
“What we’ve seen is a huge boom in deliberate jamming and spoofing. From a few dozen, maybe 100 attacks a day, to routinely over 1,000 attacks a day,’’ says Biercuk.
Q-CTRL has developed the world’s first quantum technology enhanced navigation system, that could one day soon make its way into cars on the road.
‘’If you have a sufficiently good detector of magnetic fields called a magnetometer, you can measure not just the direction of Earth’s field, but you can measure tiny little bumps and wiggles that come from differences in Earth’s crust,’’ says Biercuk.
That is cross-referenced to a detailed map of the magnetic variations, allowing for extremely fast, extremely accurate positioning. This ‘new set of eyes,’ is based on trapped rubidium atoms, that spin like compass needles.
A laser is used to measure them, and this is where the quantum physics comes in. A process known as Ramsey Interferometry exploits Superposition. Giving the atom a little kick with a laser puts it half way between two states, and behavior depends on the strength and direction of the magnetic field. Another kick settles it down into a stable reality. Measure the Interference pattern of all these spinning atoms, and you get an accurate reading.
‘’It’s very, very stable over time, and those properties of sensitivity and stability are a key differentiator of quantum magnetometers, quantum sensors in general,’’ says Biercuk.
In the field, it’s almost as accurate as satellite GPS and about 100 times as accurate as the current backup, known as Inertial Navigation Systems. This technology is not meant to replace satellite, but serve as a vital alternative when things go wrong, and allow for navigation in dense urban areas, underground, and GPS-denied conflict zones.
“There are already some quantum instruments that are in service now, and we really believe that quantum technology offers a very interesting competitive advantage for gravity measurements”
Bruno Desruelle, CEO, Exail Photonics Divison, co-founder of Muquans
Quantum computing
It’s a problem that keeps transportation experts up at night, how do you route millions of trains, buses, cars and trams, through a densely packed urban environment efficiently, all with constantly changing conditions, in close to real-time? ‘’We’ve spoken to some of the private transport providers in Australia, they indicate that when they make a schedule, they’ll allow a supercomputer to run for 40 or 50 hours just to come up with a it,’’ says Biercuk.
Another quantum computing company, the world’s first supplier of quantum computers, D-Wave Quantum Inc, has run a series of pilots with Denso for optimizing taxis and ridesharing services. One such case study in Kyoto found that the number of vehicles for 400 rides was lowered from 62 to 43, a massive 30% reduction. That has huge implications for urban congestion. Another case study in Bangkok found a small fleet were able to carry out the same number of stops with a 10% reduction in mileage and driving time. So how are they achieving this? And where does quantum computing step in?
It’s a mathematical problem that requires an advanced algorithm. D-Wave tried a couple of approaches, but one solution, known as the Constrained Quadratic Model (CQM) was head-and-shoulders the clear winner. As complexity increased with more vehicles, they found that slightly less-than-perfect solutions were a sweet spot that balanced route efficiency with computing efficiency. Sacrificing 10% of the max routing efficiency was 100 times faster.
While it might be tempting to think of quantum computers as very fast PCs, in fact they aren’t universally faster than regular PCs. In fact, for most everyday tasks like browsing the web, editing documents, or even playing games, a quantum computer would be terrible (if it could even do them at all).
The key is that quantum computers excel at specific types of problems where they can dramatically outperform classical computers. Quantum computers excel when factoring large numbers, modeling molecular behavior, drug interactions, or materials science and in certain optimization problems, like route optimization or financial modeling.
A quantum computer isn’t a ‘faster PC’ – it’s more like a specialized processor for specific mathematical problems. It’s the difference between a sports car and a submarine. The submarine isn’t a ‘faster car’ – it just operates in a completely different domain where cars can’t go at all.
“These most recent updates to our CQM hybrid solver reflect our commitment to building solutions that bring real enterprise applicability and impact today,” says D-Wave’s vice president of Software, Algorithms and Cloud Services, Trevor Lanting. “We’re excited by the performance enhancements that we are seeing, and our rapid pace of innovation allows us to expand quantum hybrid workflows to help solve increasingly complex problems.”
D-Wave links up a traffic system via its Leap Cloud Service, this connects the vehicle to the quantum computer. It operates on an Ising Hamiltonian, which is a network of qubits (quantum processing units) links with tunable couplings and local fields. The ‘ground-state’ or lowest energy configuration of the system corresponds to the ‘best’ solution to the problem. This is known as ‘quantum annealing’.
“Anything that gains back a little bit of computational time or delivers a little bit of advantage in say how tightly packed a schedule is, those advantages really accumulate when the problems are at large scale like an urban transport network or a highway network”
Michael J Biercuk, CEO, Q-CTRL
Quantum annealers perform the advanced optimization equations in a physically native way. The equations and the underlying physics are basically like-for-like. Classical methods chug along behind because of the combinatorial explosion, the huge number of possible configurations as complexity increases. Annealers, however, can engage in quantum tunneling, a specialist case of Superposition.
Imagine going down a maze the wrong way, but you ‘jump over the wall’ when you hit a dead end, rather than having to start again. It doesn’t guarantee that the next path will be the best one, but it does speed up the process immensely.
“Anything that gains back a little bit of computational time or delivers a bit of advantage in say how tightly packed a schedule is, those advantages really accumulate when the problems are at large scale like an urban transport network or a highway network,” says Biercuk.
Quantum vision
Quantum Technologies allow for another type of highly accurate sensor, this one can measure minuscule variations in gravity. They are so sensitive that they can detect under-road cavities, warning of potential dangers.
Known as a quantum gravimeter, they are like X-Ray specs for infrastructure, and could revolutionize asset management. There are a few already on the market for geological surveying and mine safety, such as Absolute Quantum Gravimeter (AQG) by French start up Muquans, integrated into Exail in 2021.
‘’There are already some quantum instruments in service now, and we really believe that quantum technology offers a competitive advantage for gravity measurements,’’ says Bruno Desruelle, co-founder of Muquans and now CEO of Exail Photonics Divison.
They are traditional bulky affairs, but the lack of moving parts make them good candidates for miniaturization – and there are already ‘backpack sized’ prototypes demonstrated. Likely they will first appear on heavy industrial machinery and trucks, and later perhaps on the ordinary automobile.
As with magnetometers, the quantum gravimeters advantage over the non-quantum instruments is precision, stability, sensitivity and robustness. Spring-loaded gravimeters also suffer from instrumental drift and require constant recalibration. With vibration-cancelling additions, these units have been mounted on trucks, ships and aircraft. Cavity size also matters. Conventional gravimeters can spot a 10m wide cavity 20m below the surface. But smaller voids are still dangerous, and quantum gravimeters can detect cavities as small as 1-2m wide at the same depth.
‘’Another key application area is the management of below ground assets (e.g. pipes and cables),” says the DfT report. “With an incomplete and inaccurate asset inventory driving major costs for the transport sector. Quantum sensors such as magnetometers and gravitometers can play a critical role in preventing damage and delays, and enabling proactive asset maintenance through remote condition monitoring.’’
Some regions have a dire need to see these issues well before they arise. Take Florida, with its karstic limestone landscape. The soluble rocks dissolve over time leading to sinkholes which pose major safety risks and economic losses if not spotted. It’s a vast, weird and exciting world opening up in an already dynamic sector. quantum computing is likely to remain mostly experimental for a few years while experts iron out the wrinkles, however quantum navigation and quantum sensing are ready-to-go.
There’s going to be fierce competition between different modalities in processing – with each solution having its pros and cons. Also the outlooks could be very different if you consider the near-term most matured technologies versus what could dominate in future.
Traffic managers and civil servants need to start wrapping their heads around how this works – just a little. For the most part, firms are designing out-of-the-box solutions that hide their quantum magic behind a slick user-interface. However, the more we understand the technologies, and their challenges, the more we’ll be able to make the most of their vast potential.
Quantum cybersecurity in space
In space, no-one can hear you scream. With quantum key distribution (QKD) the idea is nobody will hear your communications either. Today, there’s only one such satellite, China’s Micius (QUESS), but six more are in development from Canada, Japan and the European Space Agency.
Here’s how it works: in the E91 protocol a photon is split into a pair of quantum twins that are entangled and so spin in the same direction. One photon goes to the receiver and another to the sender.
Eavesdropping will disturb the quantum state, and statistical analysis gives a Quantum Bit Error Rate that estimates how many photons were disturbed. If it’s beyond 11% it’s indication of snooping, in which case a new key is set.
The method is still somewhat probabilistic – it’s still possible to sneak a peek at the key without anyone knowing, just far less likely.
The same methods are used in fiber optic cable, but don’t work well over vast distances like orbital satellite. There are even projects like QCmobility and QI-TraSiCo developing QKD as a high-trust protocol for connected transportation applications. For QKD higher orbit satellites like GEO at 36,000 km lead to unacceptable levels of photon loss from distance and atmospheric distortion. Those delicate quantum states much prefer the sweet and lowdown of low earth orbit (LEO) satellite at the lower end of 300-2000km band of the stratosphere. At that spot decoherence, scattering and noise are reduced.
The Micius sits an altitude of 500km above this green-blue marble. Singapore’s SpeQtral will sit in sun synchronous orbit, spinning its circuit at 600km.
Like all communications, distance takes time, which means the lower the satellite, the lower the latency. The higher orbital velocity of LEO also means multiple passes per day – and refreshing the quantum key entanglement frequently is a winning formula for better reliability and security. The challenge is that connection-time-perground- station is short, necessitating vast continuous QKD satellite constellations much like the Starlink network.
LEO-QKD is of great interest to numerous companies, states, and traffic tech boffins, and everyone wants to get in on the action. Nokia, Colt and Honeywell just announced a collaboration on this fascinating emergenttech mashup. Honeywell is also teaming up with Redwire on ESA’s QKDSat program, while Rivada Space Networks is calling on SpeQtral to provide the QKD layers for joint validation on a 300-satellite laser-linked network.
Q-DAY: THE CYBERSECURITY RISK
Q-Day is a cybersecurity term for a future scenario when Quantum computers become available with the capacity to break standard encryption, gaining access to all sorts of sensitive data and sensitive infrastructure systems like traffic management suites.
The RSA cryptosystem is one of the widest used encryption techniques, and it works by calculating impossibly large prime numbers. Current computing power cannot crack it, but an effective Quantum computer could by using Shor’s algorithm.
There’s more motive than ever to disrupt logistics through cyberwarfare, so this has security services and transportation civil servants concerned. Bad Actors are known to store large amounts of encrypted data, to crack in the future, in what’s known as harvest now decrypt later (HNDR) But experts think that we might not need quantum computers to counter this, and are busy making quantum-resilient encryption based off different math problems, so today it is possible to be quantum resilient in cybersecurity.
$15m – The typical cost of a quantum computer, which will stand about 3m tall
600 – The kWh of electricity consumed by a quantum computer per day (20 times an average US household
-273 – The temperature in °C (absolute zero) that a quantum chip must be kept near to in order to operate effectively
