Why do we need quantum computers?
When scientists and engineers encounter difficult problems, they turn to supercomputers. These are very large classical computers, often with thousands of classical CPU and GPU cores. However, even supercomputers struggle to solve certain kinds of problems.
If a supercomputer gets stumped, that's probably because the big classical machine was asked to solve a problem with a high degree of complexity. When classical computers fail, it's often due to complexity
Complex problems are problems with lots of variables interacting in complicated ways. Modeling the behavior of individual atoms in a molecule is a complex problem, because of all the different electrons interacting with one another. Sorting out the ideal routes for a few hundred tankers in a global shipping network is complex too.
How do they work?
A classical processor uses bits to perform its operations. A quantum computer uses qubits (CUE-bits) to run multidimensional quantum algorithms.
A qubit (quantum bit) is the fundamental unit of information in quantum computing. The qubit (CUE-bit) was first used by Benjamin Schumacher and it represents the core building block for the future quantum computers.
In classical computing the unit of information is the bit which can have one of the two values: 0, 1. A qubit, on the other hand, can have states 0, 1, or a combination of 0 and 1. The combination of both states is called superposition, an important concept of quantum computing. Whereas the state of a bit is like flipping a coin resulting in one of the two options,, the state of a qubit is like the position of an electron in its spherical (circular) orbit.
- The position of the electron in the “north” position could represent 1 and the electron in the “south” position could represent 0.
- Any other location in the orbit is a combination of 0 and 1 and is the superposition mentioned above (somewhere between 0 and 1).
Image source: Wikimedia Commons
