Stealing from the company's bank accounts could earn you time in the big house. But embezzlement from a quantum ledger might not be against the law.
In fact, a new study finds it might be a handy way to entangle particles without messing up their mathematics.
Earlier this century, quantum computing researcher Wim van Dam and physicist Patrick Hayden described a process they called embezzling entanglement, named for the light-fingered approach some systems could potentially take to combining their numbers without leaving a trace.
Theoretical physicists Lauritz van Luijk, Alexander Stottmeister, Reinhard F. Werner, and Henrik Wilming of Leibniz University Hannover in Germany have now identified fields that could be key players in this unusual quantum heist.
Our physical Universe – where objects have very clearly defined properties like location, momentum, and energy – emerges from an unresolved version of reality consisting of maybes and likelihoods.
As uncertain as this existence is prior to being locked down by a measurement, the laws governing its operation are as strict as those of any casino. Interactions with additional particles can upset the odds as easily as an extra deck of cards could change how a game of poker is played.
Entanglement is both a handy tool and a foil for any physics card counter.
Done right, entanglement can be used as the basis of powerful algorithms combining the probabilities of hundreds or even thousands of quantum card games. In the form of random intrusions, they can turn a useful quantum state into meaningless chaos.
Mathematically speaking, it's possible to show some quantum transformations are more subtle than others. One type of change returns to a state that doesn't appear to be disturbed, for example. Described as a kind of catalyst, this reversal allows for computing operations that wouldn't have been possible in cases where end states are altered.
Where van Dam and Hayden demonstrated that catalysts could universally flip any entangled state on a whim, the researchers at Leibniz University have now algebraically demonstrated that a combination of general relativity and quantum field theory can result in a bottomless pit of catalysts.
In theory, a relativistic quantum field could serve as an infinite resource of embezzlement, entangling with particles in ways that wouldn't alter their delicate states.
"Since the bank is in the same state before and after the embezzlement, that means that no one can detect it," van Luijk explained to New Scientist's Karmela Padavic-Callaghan. "It's the perfect crime."
To become a practical system, a physical equivalent of a suitable field would need to be identified. Right now, embezzling entanglement is more of a mathematical abstraction than a 'how to' guide for silently stealing from the Universe.
Yet knowing infinite levels of entanglement could naturally be occurring in absolute nothingness could point the way to a whole criminal underworld of physics, where different classes of theft occur right under our noses.
This research has been accepted for publication in Physical Review Letters.