Hope for quantum information

Physicist Adam Frank writes in the NY Times:

Given its importance, many of us in the physics community expected the event to earn this year’s Nobel Prize in Physics. Instead, the award went to achievements in a field far less well known and vastly less expensive: quantum information. ... It could well usher in a radical new era of technology, one that makes today’s fastest computers look like hand-cranked adding machines.

All of our computers today depend on quantum information, so new research is great, but it is not going to do what Frank says.

He tries to summarize the Interpretations of quantum mechanics:

Take the superposition debate. One camp claims that a deeper level of reality lies hidden beneath all the quantum weirdness. Once the so-called hidden variables controlling reality are exposed, they say, the strangeness of superposition will evaporate.

Another camp claims that superposition shows us that potential realities matter just as much as the single, fully manifested one we experience. But what collapses the potential electrons in their two locations into the one electron we actually see? According to this interpretation, it is the very act of looking; the measurement process collapses an ethereal world of potentials into the one real world we experience.

And a third major camp argues that particles can be two places at once only because the universe itself splits into parallel realities at the moment of measurement, one universe for each particle location — and thus an infinite number of ever splitting parallel versions of the universe (and us) are all evolving alongside one another. ...

Soon at least one interpretation, the most common sense version of hidden variables, was completely ruled out.

The hidden variable interpretation has been ruled out by the quantum mechanics textbooks since about 1930. Einstein, Bohm, Bell, and a few others tried to ressurect the idea, but they were always proven wrong.

The third interpretation, many-words (MWI), has several serious defects. First, it postulates zillions of worlds with no observable consequences. Second, it does not make any computation or understanding of our world any easier. Third, it is philosophically self-defeating, like denying free will.

A quantum machine using no more than 300 qubits would be a million, trillion, trillion, trillion times faster than the most modern supercomputer.

Going even further is the seemingly science-fiction possibility of “quantum teleportation.” Based on experiments going on today with simple quantum systems, it is at least a theoretical possibility that one day objects could be reconstituted — beamed — across a space without ever crossing the distance.

This is fiction. No one has even made one scalable qubit. Even a 300-qubit quantum computer would only be faster on certain obscure search functions of limited utility. And no one has found any use for quantum teleportation.

Update: Greg Kuperberg writes in Slate:

Of course, I was thrilled that the Nobel Foundation recognized this field. However, I was dismayed to read in the press release that "a quantum computer of only 300 qubits could hold 2³°° values simultaneously." Actually, 300 qubits can't hold so many zillion values; it is a mathematical fact that 300 qubits can store only 300 bits. This press release is part of a larger pattern of breathless exaggerations. In the name of accessibility, many popular accounts take quantum computing to implausible levels of hype.

A comment says:

Basically, once we have a fully scaled up quantum computer we will have cures for all sorts of diseases(protein folding problems will be solved quickly), space travel and worm holes, teleportation advances, nuclear fusion. This will be the biggest technological revolution that the planet has ever seen. Believe it or not, that day is coming and soon 5-10 yrs.

No, I do not believe that day is coming in the 1000 years.