【单选题】

Computing is driving the philosophical understanding of quantum theoryFor evidence of the power of simplicity, you need look no further than a computer.Everything it does is based on the manipulation of binary digits, or bits-units of information that can be either 0 or 1. Using logical operations to combine those 0s and Is allows computers to add, multiply and divide, and from there go on to achieve all the feats of the digital age.But at each step of the complex operations involved, each bit has a definite value.The same cannot be said of many properties in quantum physics, such as the spin of an atomic nucleus or the position of an electron orbiting such a nucleus.At a small scale, such properties can have more than one value at once. In 1994, Peter Shor, a mathematician then atAT&T’’sBell Laboratories in New Jersey, realised that a computer that used such quantum properties to represent information could factorise large numbers extremely quickly. This is an important problem, because much of modern cryptography is based on the difficulty of factorising large numbers -- so being able to do so quickly would render many modern codes easily breakable. Then, in 1996, a colleague ofDr Shor’’s atBell Labs, Lov Grover, showed that such a quantum computer would be able to search through an unsorted database much faster than an ordinary computer -- another important application.With these insights, quantum computing, which had first been thought of as a possibility in the early 1980s, became a hot topic of research. It was clear to many physicists that using "qubits" -- which, unlike ordinary bits, can exist in a "superposition" of the values 0 and 1 simultaneously -- might yield an exponential improvement in computing power. This is because a pair of qubits could be in four different states at once, three qubits in eight, and so forth. WhatDr Shor andDr Grover showed was that the improvement, if the technological hurdles could be overcome, would be not hypothetical, but real, and useful for important problems.The technology necessary to manipulate qubits, in their various incarnations, is challenging. So far, nobody has managed to get a quantum computer to perform anything other than the most basic operations.But the field has been gathering pace, and is the topic of much discussion among the scientists gathered in Montreal for the annual March meeting of theAmerican Physical Society, the largest physics conference in the worl

D、There are currently several different approaches to quantum computing, all of which rely on fundamentally different technologies, including ultra-cold ions that are cooled by lasers, pulses of laser light, nuclear-magnetic resonance and solid-state devices such as superconducting junctions or quantum dots (which are confined clouds of electrons). What all these technologies have in common is that they can be used to invoke and exploit the bizarre phenomenon of superposition.Superposition is not simple. Though a qubit may, for a while, be in a state of superposition between 0 and 1, it must eventually choose between the two.And in even the best quantum computers, that choice, or "decoherence", happens in a fraction of a millisecon
D、Just how the choice is made, and how to prolong the preceding period of "coherence" that allows quantum computations to be made, constitute a long-unexplained gap at the heart of modern physics. For nearly 80 years, since the inception of quantum theory in the 1920s, most physicists were content to gloss over the process. What is perhaps surprising is that the technological challenge of quantum computing is now a driving force behind efforts to understand the most abstract and philosophical underpinnings of quantum mechanics. At each step of the complex operations involved, each bit has a blurry value.
A、True
B．False
C．NOT GIVEN