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Quantum computing pioneer Seth Lloyd is the 2019 Lorentz Professor

American physicist and quantum computing pioneer Seth Lloyd is the 65th Lorentz professor. He will deliver the Ehrenfest lecture on 5 June, and several more lectures on quantum computing on 11, 18 and 25 June.

Quantum mechanics for calculations

In 1993, MIT physicist Seth Lloyd (1960) described the first technically feasible design for a quantum computer. This is a computer that can solve specific calculations much faster than present, regular computers. He also played a pioneering role in the theoretical foundations of the fast growing field of quantum information.

Being in several states at once

In quantum mechanics, a physical system, like an atom or an electron, can be in a superposition, which means that it exists in several states at once. A famous but caricatural example is Schrödinger's cat, which would be dead and alive at the same time.

Quantum computers exploit these superpositions, because a quantum bit, qubit for short, can be a 1 and a 0 simultaneously. In Lloyd's words: 'A classical computer can typically only follow one instruction at a time, but a quantum computer can do many things simultaneously.'

The universe as a supercomputer

Seth Lloyd is the 65th Lorentz professor, a visiting professorship on the invitation of the Lorentz Institute for Theoretical Physics, a department of the Leiden Institute of Physics (LION).

Lloyd takes a broad view of the concept of quantum information. In 1988, he graduated on the doctoral thesis entitled ‘Black Holes, Demons, and the Loss of Coherence: How Complex Systems Get Information, and What They Do With It’. 

In 2006, he published his book Programming the Universe, that considers the laws of nature and the entire universe as a giant quantum information processing system. ‘Every physical system registers information, and just by evolving in time, by doing its thing, it changes that information, transforms that information, or, if you like, processes that information.’ Lloyd calculated the maximum processing power of the known universe, and stated that Moore’s law, on ever faster computer chips, will come to an end at last in 600 years, ‘when the whole universe runs Windows 2540’

‘Like fools, we didn’t patent it’

In 2002, together with graduate student Bill Kaminsky, Lloyd described a quantum annealer, a special type of quantum computer based on superconducting circuits. But their analysis also showed that it could never work perfectly. ‘Like fools, we didn’t patent it’, he said in an interview.

The company D-wave built the design anyway, and sells it to companies like Google and to NASA, where, mysteriously, it seems to find solutions to complex calculations, regardless of it’s supposed inability.

Quantum mechanical chlorophyll

Later, Lloyd aimed this attention to delineating the kind of problem where quantum computers can deliver their miraculous speedup, and to research into quantum effects in nature. For instance, the chlorophyll molecule in plants deploys quantum effects to render photosynthesis more efficiently.

In recent interviews, he spoke about the combination of quantum computing and machine learning, about whether intelligent computers can be conscious, and about the future of quantum computing as a possible breakthrough technology.

Lloyd is the director of the Center for Extreme Quantum Information Theory (xQIT) at the Massachusetts Institute of Technology (MIT). But, having his academic roots in mechanical engineering, he also likes to refer to himself as a ‘quantum mechanic’.

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