Frontier · Module 18
Information turns out to be physical, and physics turns out to be informational. This module is where quantum mechanics stops being a description of nature and becomes a technology.
By the end of this module
You can explain why a quantum computer is fast at some things, and honestly slow at most others.
What can a qubit do that a probabilistic bit cannot?
John Preskill, Caltech
The canonical free graduate notes in the field.
Xanadu
Learn by writing quantum code in the browser, with instant feedback.
What is actually transmitted in quantum teleportation?
IBM
John Watrous's course, free and rigorous.
Bennett et al., PRL 1993
Where does the speed-up actually come from?
Peter Shor, 1994
The paper that made everyone care.
Lov Grover, 1996
How do you protect a state you are not allowed to look at?
Peter Shor, 1995
What is physically hard about this, and what is merely expensive?
IBM
Free access to real quantum processors.
David DiVincenzo, 2000
The five criteria every hardware platform is still judged against.
Check yourself
Every answer comes with the reasoning, not just a verdict. Getting one wrong and reading why is the point.
01A quantum computer's advantage comes principally from:
02The no-cloning theorem says you cannot copy an unknown quantum state. This follows from:
03Quantum error correction is possible despite no-cloning because: