As quantum mechanics turns 100, it is sneaking into everyday life

There is no science more removed from practical life than quantum mechanics. Or so I thought.

In the 100 years since it was first developed — 2025 is the field’s centenary year, more or less — the physics of the very small has done away with almost everything we take for granted, such as being able to know where things are. It seems like the ultimate scientific enigma wrapped in mathematical mystery inside a philosophical riddle, disconnected to the everyday world.

Not so, says David Mattingly, an associate professor of physics at UNH. “It’s on the verge of being practical. My last student now is a quantum software developer. He actually writes programs for quantum computers — that’s his job.”

In fact, Mattingly says, most humans, including me, have things backwards when it comes to quantum mechanics. It’s not weird; we are.

“Quantum mechanics is the way the world works and we are built on top of it — rather than it being a deviation from the way the world works,” he said. “The fundamental world is quantum mechanical.”

As I’m sure you know, dear reader, the quantum world of atomic and sub-atomic existence is probabilistic, as reflected by Schrodinger’s cat and Heisenberg’s uncertainty, unlike the world we see around us.

“The actual states are probabilistically distributed. It can be here and there, not here or there,” Mattingly said.

This fact, called superposition, seems like a flaw that gets in the way of exactitude. But actually it’s a strength, an extra resource to use, Mattingly said. Entanglement, the action-at-a-distance that links disparate particles, is another example of something available at the quantum level that isn’t available in “normal” space.

“If we have enough control of quantum systems we can use those quantum resources to do things we couldn’t have done otherwise,” he said.

Consider computers. “A.I. right now can give you rapid answers but it requires a lot of processing power and a lot of energy to do so. With quantum computing, since we have entanglement and superposition, we can construct quantum computers to spend those resources instead, to efficiently solve problems.”

Or Alzheimer’s treatment.

One of the causes of Alzheimer’s is thought to be a build-up of amyloid proteins. There are methods of making the proteins visible by hitting them with photons from two lasers at once, making them glow fluorescently. Zapping living tissue with lasers is dangerous, however. Enter quantum entanglement.

“You can entangle the photons and that increases the chance that you’ll have the electrons in the proteins jump up and fluoresce … That means you can dial down the energy and do less damage to the tissue: dial up the entanglement and still do your imaging.”

Quantum mechanics dates back to 1900, when Max Planck developed the idea of quantum states, but 1925 is being touted as its birth year because several papers were published that grounded the idea as a real science. The field has been percolating ever since, even if it feels to those of us in the public like nothing much has happened.

“The new thing is the understanding of quantum information, which started in the 1970s and 80s. That is what allowed us to start controlling these resources and now you’re finding commercial applications,” Mattingly said.

And therein lies an important point about expanding human knowledge. You’ve got to start somewhere, even if that somewhere seems too weird to ever be useful.

“This is why fundamental research is needed, because of this progression over the decades from fundamental … to commercial applications,” Mattingly said.