Quantum Computing: A Primer

When things get small — like atoms and electrons small — physics gets weird. Schrödinger’s Cat weird. Quantum superposition weird. Quantum entanglement weird. Atoms, electrons and photos obey quantum mechanical laws so spooky (Einstein’s word for it) and complex, we can’t even simulate them with our most advanced supercomputers.

Because we can’t simulate quantum behavior, legendary and Nobel Prize winning physicist Richard Feynman proposed building a new class of computers called quantum computers which “hitch a ride” on quantum mechanical properties to try and model this behavior.

So what is a quantum computer? How is it different from a traditional transistor-and-Boolean algebra computer like the one you are reading this on? What can a quantum computer do that a traditional computer can’t do? What practical applications are there? Will quantum computers mean the end of crypto as we know it? And how accurate was Canadian Prime Minister Justin Trudeau on that day he won the Internet with his explanation of quantum computing?

In this primer, I unpack the basics and describe why many of the biggest companies, research universities, and nation states are investing heavily in the development of quantum computers. And how perhaps now is the right time for startups to join the quest.


The Bloch sphere is a representation of a qubit, the fundamental building block of quantum computers

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