How a quantum computer is different from your laptop, explained by a scientist

A conventional computer uses electricity within its silicon chips. Small amounts of electrical current are turned on or off. It represents true and false, or the binary numbers one and zero.

But a quantum computer changes individual quantum elements such as electrons or photons, called qubits. Due to their 'spin', electrons can be up or down, and photons vertical or horizontal at the same time. This quantum superposition means that a qubit is in both states at once.

Qubits rely on a property known as entanglement - the property of one particle is entangled with another.

When there are two entangled particles with a combined spin of zero and one particle collapses so that it spins clockwise, the other particle's state will be anticlockwise. This means, once entangled, qubits can be used to represent massive numbers. For example, Google's quantum computer Sycamore had 53 qubits, meaning it could represent over ten quadrillion combinations simultaneously.