"Hacking the Cosmos" --Photon-Based Quantum Computing
- URL to an interesting article from The Daily Galaxy
I read that quantum computers will be available at Best Buy by Christmas
the first in your neighborhood to get answers BEFORE you ask the questions!
First few paragraphs
"_Quantum computers_ (http://en.wikipedia.org/wiki/Quantum_computer) can
efficiently render every physically possible quantum environment, even when
vast numbers of universes are interacting. Quantum computation is a
qualitatively new way of harnessing nature," according to _David Deutch_
(http://en.wikipedia.org/wiki/David_Deutsch) , an Israeli-British physicist at the
_University of Oxford_
(http://maps.google.com/maps?ll=51.7611,-1.2534&spn=0.01,0.01&q=51.7611,-1.2534 (University%20of%20Oxford)&t=h) who pioneered the
field of quantum computation and is a proponent of the many-worlds
interpretation of quantum mechanics. Quantum computers, says Deutch, have the
potential to solve problems that would take a classical computer longer than the
age of the universe.
In a new development, scientists from the Group of Philip Walther from the
Faculty of Physics, University of Vienna succeeded in prototyping a new and
highly resource efficient model of a quantum computer -- the boson
sampling computer. Quantum computers work by manipulating quantum objects as, for
example, individual photons, electrons or atoms and by harnessing the
unique quantum features.
Not only do quantum computers promise a dramatic increase in speed over
classical computers in a variety of computational tasks; they are designed to
complete tasks that even a supercomputer would not be able to handle. In
recent years, there has been a rapid development in quantum technology the
realization of a full-sized quantum computer is still very challenging.
While it is still an exciting open question which architecture and quantum
objects will finally lead to the outperformance of conventional supercomputers,
current experiments show that some quantum objects are better suited than
others for particular computational tasks.
The huge advantage of photons -- a particular type of bosons -- lies in
their high mobility. The research team from the University of Vienna in
collaboration with scientist from the University of Jena (Germany) has recently
realized a so-called boson sampling computer that utilizes precisely this
feature of photons. They inserted photons into a complex optical network
where they could propagate along many different paths.
"According to the laws of quantum physics, the photons seem to take all
possible paths at the same time. This is known as superposition. Amazingly,
one can record the outcome of the computation rather trivially: one measures
how many photons exit in which output of the network," explains Philip
Walther from the Faculty of Physics.
A classical computer relies on an exact description of the optical network
to calculate the propagation of the photons through this circuit. For a few
dozen photons and an optical network with merely a hundred inputs and
outputs, even today's fastest classical supercomputer is unable to calculate
the propagation of the photons. However, for a boson sampling computer this
ambitious task is within reach. The researchers met the challenge and built
their prototype based on a theoretical proposal by scientists at the
_Massachusetts Institute of Technology_
"It is crucial to verify the operation of a boson-sampling computer by
comparing its outcome with the predictions of quantum physics. Ironically, this
test can only be performed on a classical computer. Fortunately, for small
enough systems classical computers are still able to accomplish this," as
Max Tillmann, first author of the publication, points out. Thus, the
researchers successfully showed that their realization of the boson-sampling
computer works with high precision. These encouraging results may lead the way
to the first outperformance of classical computers in the not-so-far
Meanwhile, astrophysicist Paul Davies at _Arizona State University_
0.01&q=33.4211111111,-111.931666667 (Arizona%20State%20University)&t=h) proposes that
information, not mathematics, is the foundation on which physical reality,
the laws of nature, are is constructed. Meanwhile at MIT, computer scientist
_Seth Lloyd_ (http://en.wikipedia.org/wiki/Seth_Lloyd) , develops Davies
assumption, by treating quantum events as "quantum bits," or qubits, as the
way whereby the universe "registers itself."
Lloyd proposes that information is a quantifiable physical value, as much
as mass or motion -that any physical system--a river, you, the universe--is
a quantum mechanical computer. Lloyd has calculated that "a computer made
up of all the energy in the entire known universe (that is, within the
visible “horizon” of forty-two billion light-years) can store about 1092 bits
of information and can perform 10105 computations/second."
The universe itself is a quantum computer, Lloyd says, and it has made a
mind-boggling 10122/sec computations since the Big Bang (for that part of the
universe within the “horizon”).'
(Madness takes its toll. Please have exact change)
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