Quantastic

Quantastic is a very simple Quantum Computer Simulator written in Java.

The main goal for this project at the moment is to prove to myself that I understand how quantum computers work. This code will be part of a presentation I'm writing for some future conferences.

The code is surprisingly short, almost everything is just a matrix calculation done using Apache's commons-math3.

Simulator

The main class in the code (at the moment) is QSystem. This class contains the virtual qubits.

The Gates class has some predefined gates, including Pauli-gates, Hadamard, C-NOT and even Fourier. Other gates should be easy to implement, they are just matrix calculations after all.

An example of how to use the system can be found in QuantumComputerSimulator.

Example

I've chosen a fluent-API style way of constructing your quantum algorithm, this might change in the future.

Here we have a simple 1-qubit system with one gate, the Hadamard gate. This gate puts the qubit in a so called superposition. Much like Schrödingers Cat we don't know what the value is, only once measued we know if the cat survived.

        new QSystem(1)
                .applyGate(Gates.HADAMARD_GATE, 0)
                .print()
                .measure();

Output:

Applying gate:
	(0.7071067811865475, 0.0)(0.7071067811865475, 0.0)
	(0.7071067811865475, 0.0)(-0.7071067811865475, 0.0)
Current state of system:
	0: (0.7071067811865475, 0.0)
	1: (0.7071067811865475, 0.0)
Chances for qubits measured ON:
	0: 0.50%

Measurement:
	Value: 0.5934134608134609
	State: 1

State: 1... our cat is dead.

Future

I might add more functionality in the future, hoping to be able to implement more advanced Quantum Algorithms like Shor.

Also: Keep an eye out for the presentation I'm making for a conference near you! (Maybe J-Fall/Devoxx?)

(Do you want me to speak about quantum computing at your conference? Ask me!)