NSA Wants To Create A Quantum Computer In Order To Decrypt All

With its program of secret research called « Penetrating Hard Targets », U.S. agency looking to take a strategic technological advance in intelligence. But the road still seems very long.

Able to read all encrypted communications, it is the dream of all spies, and therefore also that of the NSA. And to get there, U.S. Agency began a research project of $ 79.7 million named «Penetrating Hard Targets ». Unveiled by The Washington Post on the basis of Edward Snowden documents, this program is designed to create a quantum computer dedicated to cryptanalysis. Such a machine would be able, Indeed, break any encryption code in a short time, including those based on the famous and widely used RSA algorithm.

Reduce the computational complexity

In fact, the idea of ​​creating a quantum computer to make cryptanalysis is not new. It is even the first thing that physicists have thought when they started to think about such a machine, which relies on the properties of quantum mechanics to perform calculations. Indeed, the theoretical benefits of a quantum computation is to be particularly suitable for the factorization of large integers primes. It is very difficult to achieve with conventional computers mathematical operation, because the computation time increases exponentially with the size of the number in question. Many encryption algorithms are based on precisely this mathematical difficulty to ensure the safety of the encoded message. But a quantum computer would be able to significantly reduce this complexity, thanks to Shor's algorithm (the calculation time not increase exponentially, but polynomial).

The first happens to create such a machine would have a significant strategic advantage. It therefore includes all the interest of the NSA in this area. However, according to experts interviewed by The Washington Post, the creation of a quantum computer is far from being imminent. «It seems unlikely that the NSA is so in advance with respect to companies civilians without anyone knowing about, » thus noted in the Washington Post Scott Aaronson, the Massachusetts Institute of Technology (MIT).

 The document revealed by the Post indicates that the NSA program would be about to to achieve « A dynamic decoupling with a total quantum control of two semiconductor qubits » which would allow consider moving on to higher levels. «This is a big step, but a small step towards the creation of a quantum computer large scale » estimated in the newspaper Seth Lloyd, professor of quantum mechanics at MIT.

The obstacle of the physical realization

One of the main obstacles that researchers must overcome is to physical realization of the basic element of quantum computation, the qubit. This is a bit that has the property of being able be 0, 1 or «0 and 1», thanks to the phenomenon of superposition of quantum states. However, this superposition is very difficult to control. To achieve this, it is already necessary be able to completely isolate the machine from the outside environment. That is why within the NSA, experiments were performed in «Faraday cages» which are blocking the propagation of electromagnetic waves.