Quantum Computation and Information Security

Explore quantum computation and its implications for information security in this 42-minute conference talk from CYPHERCON15. Delve into secure communication concepts, including RSA encryption and the challenges of factoring. Examine thought experiments like Schrödinger's Cat to introduce quantum bits (qubits) and their complex states. Learn about building qubits, polarizing light, and quantum key distribution. Compare classical computers built from NAND gates to quantum computers using CNOT gates and single-qubit operators. Witness an experimental demonstration of 2 qubits and understand Shor's algorithm for factoring numbers. Gain insights into the speed and potential impact of quantum algorithms on current encryption methods.

Intro
Secure Communication
RSA encryption Ron Rivest, Adi Shamir, and Leonard Adleman - Choose two prime numbers and multiply
How hard is factoring?
Thought experiment: Schrodinger's Cat
1 hour later, the cat is 50% dead
50% alive, 50% dead
Introducing the quantum bit (qubit)
A Qubit is in a complex state, with infinite possibilities
Building a Qubit
Aside on cryptography • Alice and Bob want to communicate
Polarizing Light
Represent Bits as Polarized Light
Measuring Photons
Quantum Key Distribution
What about eavesdropping?
Key Validation
Classical computers can be built from NAND gates only
Quantum Computers can be built from CNOT gates and single-qubit operators
Experimental demonstration of 2 qubits
Factoring N=15: Construct a function
Factoring N=15: Find the period
Factoring N=15: Apply QFT
Factor 15: Find the factors
How fast is Shor's algorithm?
Summary