Ronald's work had a big impact on the field of quantum information processing, and parts of his PhD thesis are now standard inclusions in textbooks on the subject. Luke: My next question leaps from quantum computing to technological forecasting.
See for example here. Most current cryptography, including electronic commerce, is based on the fact that no sufficiently fast factorisation method is known for classical computers.The work on locally decodable error-correcting codes baffled the best-known researchers in this classical area of computer science. Entangled particles can have a large distance while still influencing one another in ways that do not transfer information. Luke: Most of your work these days is in quantum computing and communication. He is able to combine great mathematical skill with intense creativity in order to solve some of the hardest problems in his field. More information. They expected that any attempt at implementing quantum bits and operations would have so much noise and errors that it would quickly decohere to a classical computer. His scientific interests include quantum computing, complexity theory, and learning theory. While I think this is more mathematics than engineering, you can certainly compare it to computer science in the s: at that point the theoretical model of a classical computer had already been introduced by Alan Turing, but no large-scale computers had been built yet. A lot of work is based on skillfully combining and applying such known quantum tools, and once in a while people find new tricks to add to our toolbox. You could already design algorithms for Turing machines on paper, and you could even prove that such computers could not solve certain problems as Turing famously did for the halting problem. Of course they had good reasons to be skeptical — manipulating something as small as an electron is extremely hard, much harder than manipulating a vacuum tube was in the s and s. Computer science has over decades been defining and studying the complexity of lots of interesting and useful computational problems and models, and often we start from there: we take an existing computational problem and try to find quantum tricks to improve over the best classical solutions.
In practice there are at least three issues with using Kolmogorov complexity to measure simplicity. Shor thus demonstrated that if one could build a quantum computer then most of our cryptographic protocols could be broken. Alternatively you can take the position that measurement is nothing special but just another interaction between quantum systems observer and observed system.
Such problems would be the benchmark on which intermediate-size QCs could be tested.
The first scenario seems the most plausible to me. Clearly building a QC is an exceedingly hard engineering problem, but my impression is that experimentalists are making slow but sure progress.This way, De Wolf hopes to achieve further cross-fertilization between these two areas, with the aim to make quantum computing more relevant even if a large-scale quantum computer would never be built. Quantum computing is an interesting field, since its researchers design algorithms, error correction techniques, etc. Alternatively you can take the position that measurement is nothing special but just another interaction between quantum systems observer and observed system. Entangled particles can have a large distance while still influencing one another in ways that do not transfer information. Interestingly, however, some of the work we are doing has spin-offs for the analysis of classical computing, and that is relevant today irrespective of progress on building a QC. Much of the relevance of this is of course contingent upon the eventual construction of a large QC. My impression is that experimental physicists are making slow but sure progress on this, and are becoming more optimistic over time that this will actually be realized within one or two decades. Ronald: The two main questions in quantum computing are 1 can we build a large-scale quantum computer and 2 what could it do if we had one. Ronald: I think that would be a wise precaution, at least for important or sensitive data. De Wolf carried out his doctoral research at CWI and the University of Amsterdam, where he graduated cum laude in There are basically three possible scenarios here: Someone constructs a large QC We discover a fundamental problem with quantum mechanics which would be extremely interesting new physics!
I myself am a theoretical computer scientist focusing on the second question. Among related fields, his PhD thesis ranks among the best worldwide over the last ten years. This is demonstrated both theoretically and practically.
This way, De Wolf hopes to achieve further cross-fertilization between these two areas, with the aim to make quantum computing more relevant even if a large-scale quantum computer would never be built.
One of these effects is entanglement.