Secrets, Magic, and Quantum Computing...• Not magic Quantum mechanics limits what is knowable •...
Transcript of Secrets, Magic, and Quantum Computing...• Not magic Quantum mechanics limits what is knowable •...
Secrets, Magic, and Quantum Computing
Dr. Aaron VanDevenderChief ScientistFounders Fund
Any sufficiently advanced technology is indistinguishable from magic.
-Arthur C. Clarke
The Force
Magic is powered by belief
Cryptography is Literally Magic
RSA Public Key Cryptography• Rivest, Shamir, Adelman invented in
1977• Uses a one-way function• Based on un-proven mathematical
conjecture that large numbers are hard to factor into their primes.
• Used for secrecy, signing, authentication, irrefutability
Belief Security
Secrets
Trust
Alice, Bob, & Eve
Digital Signatures
• Software updates• Website spoofing• Email authentication
Shor’s Algorithm
• First useful quantum algorithm (1994)• Turns factoring into a periodicity problem• Polynomial time• Will be the last to be implemented
Quantum mechanics is the cause of—and solution to—all life’s problems.
Quantum Key Distribution
• Charles Bennett, Gilles Brassard, Artur Ekert, et al.• Great for secrecy• Bad for trust• Not magic
Quantum mechanics limits what is knowable
• Heisenberg uncertainty principle• Cannot measure position and momentum at the same time• The universe keeps secrets
No cloning theorem• Quantum states cannot be copied• Attempting to measure alters the state• WPA2 KRACK
Public Key Infrastructure
• Web of Trust• State distribution contrary to no-cloning• State estimation
Reversible Computation
• Irreversible computation embeddable in reversible
• Quantum computation superset of classical
• Energy loss during erasure• Time reversal symmetry
Rubik’s Cube
• Reversible• Linear transformations • Operations are rotations• Don’t create or destroy information
• Require irreversibility• One-way functions• Hash functions• Fully avalanched
Cryptography Primitives
BitCoin• SHA-256 vulnerable to Grover’s algorithm• Only quadratic• Signed transactions are vulnerable• New network design
Quantum Money
• Stephen Weisner, Scott Aaronson, Paul Christiano, Andrew Lutomirski, et al.
Post-quantum cryptography• Lattice codes• Error correcting codes• Multivariate codes• Magic! (but maybe stronger magic)
Gödel’s Incompleteness Theorem
The only way of discovering the limits of the possible is to venture a little way past them into the impossible.
-Arthur C. Clarke
Thank you!