For much of the public, John Pendry is the man who made “Harry Potter physics” a reality. As the inventor of the theoretical framework for an invisibility cloak, he captured the imagination of the world by demonstrating how light could be bent around an object to make it disappear.
However, for Pendry, a physicist at Imperial College London, the cloak was merely a stepping stone. While the world celebrates the magic of invisibility, Pendry has moved on to a much more profound frontier: metamaterials —substances engineered to possess properties that do not exist in the natural world.
The Birth of Metamaterials
The journey began in the mid-1990s when Pendry observed how certain stealth technologies used disordered carbon fibers to absorb radar. He realized that the effectiveness of these materials didn’t come from the atoms themselves, but from their structural arrangement.
This realization birthed the science of metamaterials. Unlike traditional materials, which derive their properties from their chemical composition, metamaterials derive theirs from their geometry. By etching tiny grooves, rings, or pillars into a substance at a microscopic level, scientists can dictate exactly how waves—be they light, sound, or seismic—interact with that object.
From Science Fiction to Industrial Reality
While “invisibility” sounds like a laboratory curiosity, the commercial implications of Pendry’s work are massive. Through his long-standing professional relationship with venture capitalist Nathan Myhrvold, Pendry’s theories are being transformed into a market projected to be worth £6 billion by 2033.
The practical applications are already beginning to emerge:
- Metalenses: Instead of heavy, curved glass, “metalenses” use flat, nanoscale structures to focus light. This allows for paper-thin camera lenses in smartphones, lightweight optics for drones, and slimmer VR headsets.
- Autonomous Vehicles: Current self-driving cars rely on Lidar —bulky, rotating laser sensors. Metamaterials could allow for “solid-state” Lidar, which steers laser beams electronically with no moving parts, making sensors cheaper and more durable.
- Earthquake Protection: Because seismic waves behave mathematically much like light, metamaterials could theoretically be used to “bend” earthquake waves around a building’s foundation, shielding it from destruction.
The Next Frontier: Bending Time
Despite the industrial revolution currently underway, Pendry remains focused on the theoretical “edge” of physics. He is currently exploring temporal metamaterials —materials that change their properties not just in space, but in time.
By using ultrafast lasers to alter a material’s state in femtoseconds (quadrillionths of a second), Pendry suggests we can “transmute” energy. This could allow us to shift frequencies—for example, turning red light into blue light—by injecting or draining energy from a wave as it passes through.
This research opens doors to simulating the most extreme environments in the universe:
1. Black Hole Analogues: Pendry has calculated that a material whose internal pattern shifts at near-light speed could create a mathematical “event horizon,” allowing scientists to study black hole physics in a controlled laboratory setting.
2. Quantum Friction: He is investigating how changing electromagnetic properties in time might trigger the Casimir effect, creating a new type of quantum friction that has never been observed.
“There comes a point when your research starts running away from you,” Pendry notes. For him, the goal is not the commercialization of the cloak, but the pursuit of the next “new and exciting” mystery.
Conclusion
John Pendry’s legacy is not found in a magical cape, but in the fundamental restructuring of how we manipulate the physical world. By moving from controlling light in space to controlling it in time, he is paving the way for a future where we can simulate the heavens and master the very fabric of reality.
