Artículos con la etiqueta ‘computación cuàntica’

Future quantum computers with machine learning could attack larger sets of data than classical computers

Por • 1 ago, 2013 • Category: Ambiente

Seth Lloyd of MIT and his collaborators have developed a quantum version of machine learning — a type of AI in which programs can learn from previous experience to become progressively better at finding patterns in data. It would take advantage of quantum computations to speed up machine-learning tasks exponentially. Data can be split into groups — a task that is at the core of handwriting- and speech-recognition software — or can be searched for patterns. Massive amounts of information could therefore be manipulated with a relatively small number of qubits. “We could map the whole Universe — all of the information that has existed since the Big Bang — onto 300 qubits,” Lloyd says.



Nonlinear quantum search using the Gross–Pitaevskii equation

Por • 27 jun, 2013 • Category: Leyes

We solve the unstructured search problem in constant time by computing with a physically motivated nonlinearity of the Gross–Pitaevskii type. This speedup comes, however, at the novel expense of increasing the time-measurement precision. Jointly optimizing these resource requirements results in an overall scaling of N1/4. This is a significant, but not unreasonable, improvement over the N1/2 scaling of Grover’s algorithm. Since the Gross–Pitaevskii equation approximates the multi-particle (linear) Schrödinger equation, for which Grover’s algorithm is optimal, our result leads to a quantum information-theoretic lower bound on the number of particles needed for this approximation to hold, asymptotically



A global quantum network

Por • 17 jun, 2013 • Category: Ciencia y tecnología

By quantum-mechanically coupling laser-cooled atoms to glass fiber cables, Vienna University of Technology researchers have developed a way to store quantum information over a long enough period of time to allow for entangling atoms hundreds of kilometers apart via fiber cables. The problem with previous research is that after a short time, the quantum information stored in the atoms is lost as it leaks into the environment — an effect called “decoherence.” This finding is a fundamental building block for a global fiber-based quantum communication network, the researchers suggest.



Records The Shape of a Single Photon Unveiled in China

Por • 17 may, 2013 • Category: Opinion

The ability to store and release single photons is one of the enabling technologies for a quantum internet. These quantum storage devices are the key to quantum routers. Clearly, memories that can preserve the spatial structure of the photons will make this kind of router, and the internet it empowers, far more flexible and capable. Of course, the technologies that end up making the quantum internet of the future will depend on many other factors, not least of which will be a significant dollop of luck. But given the numerous advances in this area made by Chinese labs in recent years, only a fool would bet against Chinese technology playing a significant role in the way we quantum communicate in future



Is the ‘quantum singularity’ near?

Por • 20 ene, 2013 • Category: Ambiente

According to Dove, some in the quantum-computing community have suggested that Aaronson and Arkhipov’s experiment may be difficult enough to perform with the requisite number of photons that researchers would be better off trying to build full-fledged KLM systems.But, Dove says, “One of the ways that Scott and I like to pitch this idea is as an intermediate step that we need to do KLM.” Building a KLM optical quantum computer would entail building everything necessary to perform the Aaronson-Arkhipov experiment — plus a bunch of other, perhaps even more challenging, technologies.