Amazon AWS publishes the latest product, the Quantum Compute Cloud, or QC2 for short.
It is the first quantum computer ready to go into production. We can use it to solve certain types of math and logic problems with breathtaking speed.
Ordinary computers use collections of bits to represent their states. Each bit is definitely 0 or 1, and the number of possible states is 2n. 1 bit can be in one of the 2 states, 2 bits can be in one of the 4 states, and so on.
Quantum computers such as QC2 use a more sophisticated representation of data known as qubits or quantum bits. Each qubit exists in all of its possible states at once, but the probability that a qubit can be in one of the states can change. Quantum computers work by manipulating the probability distribution of each state.
How do you program a quantum computer? With quantum algorithms, of course. Almost everything you know about traditional programming becomes obsolete when you switch to QC2. You have to think in terms of probabilities, probability distributions, and so on. Take a look at Shor’s algorithm to find the prime factors that get an idea of the power of a quantum computer.
They are also working on support for Bernhard Omer’s QCL language. Let’s see his theses on Quantum structured programming to find out more. Here’s an example of a QCL code:
After launching a QC2 instance and loading our algorithm, we must sample the output (also known as “quantum state collapse“) to retrieve the probability distribution that represents the right answer. We may do this more than once for particular problems in order to increase confidence in the solution. The collapse of the quantum state is a destructive operation (just like reading from a magnetic core memory); Let’s make sure to factor this into our algorithm. In fact, the answer doesn’t exist until it’s asked.
Until now, the largest quantum computer contained fewer than 8 qubits. AWS was able to push this value up to 32 in the first generation of QC2. This will allow us to represent problems with up to 232 different states.
They are rolling out QC2 in US East datacenters in multiple availability zones.
The QC2 version is limited beta.