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**Quantum Computing: Why Would You Care?***By Ayo Tayo Balogun*

Quantum computers will be valuable in factoring large numbers, and therefore extremely useful for working on extremely complex encryption algorithms. Our current methods of encryption are simple compared to the complicated methods possible in quantum computers. Quantum computers could also be used to search large databases in a fraction of the time that it would take a conventional computer

**RSA Encryption and Quantum Computers***By Alastair Kay*

Any quantum computation can similarly be written as a circuit composed of two different types of gate – the Toffoli and the “square root of not”. The reason why the classical theory of computation seems self-evident, self contained and did not immediately lead to the insights of quantum computation is that one can argue this square root of not gate is impossible! To see this, a brief diversion is required. Consider a single bit, which takes values either 0 or 1. A simple operation on this bit is to flip its value, so if it’s initially 0, it ends up as 1

**Quantum Gaming – A Very Naïve Introduction***By Faisal Shah Khan*

Information theory enters the quantum physical realm when the notion of probability of occurrence of an event is appropriately generalized. To see how this works, consider first the following more formal approach to probability. We begin by noting that the probability of an event is always positive because an event can never occur a negative number of times out of a positive number of trials of some experiment, and vice versa. Next, note that as soon as an event E occurs, the complimentary event “not E”, henceforth denoted as –E, does not. In this case, associate with E the maximum possible probability of 1 or absolute certainty of occurrence, and associate with –E the least possible probability of 0 or absolute certainty of non-occurrence. This suggests that the relationship between the probability of an event and its complement should satisfy

**Who’s Afraid of the Big Bad Quantum Computer?***By Henning Dekant*

So you may wonder, what good is this vanguard of the coming quantum revolution if it can’t even handle the most famous quantum algorithm? To answer this let’s step back and look at what motivated the research into quantum computing to begin with. It wasn’t the hunt for new, more powerful algorithms but rather the insight, first formulated by Richard Feynman, that quantum mechanical systems cannot be efficiently simulated on classical hardware. This is, of course, a serious impediment as our entire science driven civilization depends on exploiting quantum mechanical effects. I am not even referring to the obvious culprits such as semiconductor based electronics, laser technology etc. but the more mundane chemical industry.

**Quantum Changes in the Cryptographic Landscape***By Joseph Fitzsimons*

While the above discussion may paint a bleak picture for cryptography in a world where large scale quantum computers are available, all is not lost. As we have seen, certain areas of cryptography, such as symmetric-key ciphers and hashes are not particularly inherently vulnerable to quantum attacks. Indeed, in these areas there do exist information theoretically secure protocols, which are of course invulnerable to quantum attacks. However, quantum attacks cause problems for areas of cryptography where such information theoretically secure classical schemes do not and cannot exist, such as public key ciphers, digital signatures and key exchange protocols.

**Quantum Computers and Information Security: Shor’s Algorithm and the Future of RSA***By Ian T. Durham*

All implementations of quantum computing fall into one of four models of quantum computation. The quantum gate array implementation most resembles a classical computer in that it uses quantum logic gates that are somewhat analogous to the similar classical gates seen in classical computation. A one-way or cluster-state quantum computer decomposes the computation into a series of single-qubit measurements made on a highly entangled initial state, i.e. a cluster state. Adiabatic quantum computation, as implemented in D-Wave’s system, decomposes the computation into a slow, continuous transformation of an operator called a Hamiltonian from an initial state to a final state whose ground state includes the solution. Topological quantum computing decomposes the computation into the braiding of particles called anyons that are two-dimensional generalizations of fermions and bosons.

**Variant Double-Path Simulation – Resolving Mysteries and Wave-Particle Paradoxes in Quantum Interactions***By Jeffrey Zhi J. Zheng, Jie-Ao Zhu & Jie Wan*

Wave-particle paradoxes forced this type of formal discussions and historical Bohr-Einstein debates without a common solution from 1900s and still an open question in modern quantum foundation. Using advanced variant logic and measurement construction, it is feasible to identify complex quantum interactions under multiple/conditional probability into a series of symmetry/anti-symmetry and synchronous/asynchronous conditions.