Quantum Computing 101 -What it is, how is it different and why it matters

Quantum is the state of things being unknown at the subatomic level until they can be observed and moves from the byte to the “qubit.”

A handout picture from October 2019 shows a component of Google's Quantum Computer in the Santa Barbara lab, California, US. (photo credit: GOOGLE/HANDOUT VIA REUTERS)
A handout picture from October 2019 shows a component of Google's Quantum Computer in the Santa Barbara lab, California, US.
(photo credit: GOOGLE/HANDOUT VIA REUTERS)
In our everyday classical computers, 0s and 1s are associated with switches and electronic circuits turning on and off as part of the computer using a binary number system to calculate possibilities and perform operations.
For example, when a computer mouse moves, a sensor tells the computer that an electrical signal has been converted into a binary value or number. Further, this number represents a location that is then represented on the computer screen – all of which is embodied by the “byte” that is the building block of current computers.
The sensor message to the computer is also saved to memory. Some calculations have too many possibilities for even a traditional computer to calculate like simulating the weather or calculating scrambled combinations of prime numbers.
Quantum is the state of things being unknown at the subatomic level until they can be observed and moves from the byte to the “qubit.” In a quantum computer, it is said that the values assigned to 0 and 1 can occur at the same time. The reason this impossibility is possible is because of quantum’s subatomic level where protons and electrons are acting in a wild way beyond the rules of nature as we tend to think of them. Picture The Avengers’ superhero Antman shrinking into the quantum zone where time did not even move in a linear fashion.
In computer terms, once the values of 0 and 1 can happen at the same time, it allows the quantum computer to consider trillions of possibilities or more in the same instant, dwarfing the number of calculations that our traditional computers, stuck in binary counting, can do.
This process is called superposition. Superposition ends once a specialized particle, or qubit, slows/is observable, thereby emerging from its quantum state. We stick the qubit in an artificial “space vacuum” so that it does not get observed or interfered with and remains dynamic. Pictures of quantum computers often show tubes the size of a household refrigerator. But most of the tubing is not the central computer processor as much as the process used to maintain the qubits at the absolute zero quantum state.
Since around 1977, RSA has been among the most widely used systems for secure data transmission underlying the Internet, serving as the backbone of the NYSE, most large institutions and most individual online users. What is stopping an average person from hacking anyone’s else’s website is that RSA is easy to build, and being based on two pseudo-random prime numbers, hard to burst for traditional computers’ limited binary system calculation capacity.
In 1994, Shoore’s algorithm, which can theoretically quickly calculate the two prime numbers underlying RSA and much of the Internet, was discovered. But machines were not fast enough to use it. Only now with quantum computers, will there be a computer system capable of utilizing all the facets of Shoore’s algorithm to calculate the trillions or more of possibilities to crack or hack RSA and much of the Internet virtually instantaneously.  
“Now” has been here for a few years with a much weaker analog cousin of quantum computing, called quantum annealing. Google produced an intermediate level quantum computer in 2019. But the full-fledged ability to crack the Internet at will is probably three to 10 years away, depending on who you ask. Once this happens, almost nothing online and no networked device will be safe.
One major hurdle to scaling up the technology is the issue of dealing with errors. Compared to bytes, qubits are incredibly fragile. Even the slightest disturbance from the outside world is enough to destroy quantum information or take them out of their quantum state and create an error that shuts everything down.
Quantum encryption, which can block a quantum computing hacking attempt, is actually ahead of quantum computing – with six to eight algorithms due to be announced in the next year or two to redo encryption worldwide. However, it may take 10 years after that to replace the whole planet’s online and physical devices old legacy encryptions. Anything not updated during that time will be exposed to quantum computing hacking at will, which could include whole economies, militaries and just about anything else.
– Y.J.B.