A New Computing Paradigm....

On February 13th, 2007 D-Wave Systems, Inc a Canadian based Quantum Computing technology startup will be launching the worlds first commercially produced end-to-end Quantum Computing system powered by a 16-bit processor.

The live launch will take place at 8am at the Computer History Museum in Mountain View, California.

Following is a brief description about Quantum Computing.

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What is Quantum Computing?

Quantum Computing is a form of computing that operates in the realm of Quantum Mechanics.

Quantum mechanics is a mathematical framework or set of rules for the construction of physical theories. For example, there is a physical theory known as quantum electrodynamics, which describes with fantastic accuracy the interaction of atoms and light. Quantum Electrodynamics is built up upon the framework of quantum mechanics. The relationship of quantum mechanics to specific physical theories like quantum electrodynamics is like a relationship of a computer’s operating system to specific applications software—the operating systems sets certain basic parameters and modes of operation, but leaves open how specific tasks are accomplished by the applications.

In a quantum computer, the fundamental unit of information (called a quantum bit or qubit), is not binary but rather more quaternary in nature. This qubit property arises as a direct consequence of its adherence to the laws of quantum mechanics which differ radically from the laws of classical physics. A qubit can exist not only in a state corresponding to the logical state 0 or 1 as in a classical bit, but also in states corresponding to a blend or superposition of these classical states. In other words, a qubit can exist as a zero, a one, or simultaneously as both 0 and 1, with a numerical coefficient representing the probability for each state. This may seem counterintuitive because everyday phenomenon is governed by classical physics, not quantum mechanics -- which takes over at the atomic level. [Click for an explanation on Classical bit Vs. Qubit]

Fig. 1: Mathematical depiction of Quantum states - above shown are two |0> and |1> states, which are vector quantities - below is a superposition or summation of the two states. The reciprocal of the square root of two are amplitudes defining part of the superposition is in the |0> state and
the rest is in the |1> state.

Note on the Notation:

In quantum mechanics a commonly used notation is referred to as the Bra-ket notation which describes quantum states. It was invented by Paul Dirac to intuitively describe quantum stats. It is also used to describe abstract vectors and linear functions in mathematics. It is called Bra-ket because the inner product of two states, say for example a x and y are denoted by a bracket . This can also be described with the integral symbol as

= Integral(x*y) dxdy

Where x* is a complex conjugate of x.

Most of quantum mechanics uses this intuitive notation which hides the underlying complexities of the mathematical description.

Why Quantum Computing?

You might be asking why we need to worry about quantum computing. Well I could state several reasons why quantum computing is important, but for the purposes of this report it would suffice to state three of most fundamental reasons:

1. Semiconductor Fabrication Costs:

With the increasing complexity of Integrated Circuits (IC’s) the over head costs of fabrication has been on a steady rise. The plot in Figure 1 depicts the cost of fabricating Semiconductors verse time.

Fig.1: Semiconductor Fabrication Cost increases with Time (Courtesy Scientific America, 2000)

2. Declining Number of Electrons per chip:

With the increasing density and reduction in physical size of the semiconductor chips die, the number of electrons per chip are on a steady decline and their quantum mechanical interaction is becoming more and more significant. The plot in Figure 2 depicts a decreasing of the number of electrons per chip with increasing time.

Fig.2: Declining Number of Electrons per chip (courtesy Scientific America, 2000)

3. Classical computers, which are based on binary 0 and 1, are not able to generate a true random set of numbers.

4. Quantum Computers are able to perform certain types of calculations that could be too lengthy for classical computers to perform.

To further learn about the theory behind quantum computing, I would strongly recommend the following text by Michael A. Nielsen, Isaac L. Chuang titled "Quantum Computation and Quantum Information".

In the meantime standby for news about D-Wave Systems, Inc's groundbreaking historical launch of the first Commercially produced Quantum Computing System.

Copyright C. 2007 Rabita Technologies, Inc