Presentation given at Singularity Salon 11/11/11 Video of presentation here: http://www.youtube.com/watch?v=DF-t4Ty54e4

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QUANTUM COMPUTING>
NOON SILK - 11/11/11

2. Quick overview, what is QC?
Computing quantumly
Classical
Quantum
Datatype
binary: 1, 0, “bit”
“qubit”, measured
value of 1,0
Operators
AND, OR, NOT,
etc.
CNot, Rotations,
anything valid
Space
= bits. 256 bits?
256 bits.
2^qubits, 256
qubits? 2^256
space. (complex)
“Measurement”
= space
= qubits (256 bits;
*collapses*)
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3. Okay, where are they?
Here!
• CQC^2T: NV Cavity, Silicon-Phosphorus,
Superconducting Grid
• Adrea Morello and Andrew Dzurak won
the 2011 Eureka Prize
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4. Purpose?
Speedup
Energy reduction for large computational
tasks
Simulation of systems that would otherwise
be intractable (quantum chemistry)
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5. Okay, research areas?
Implementation
– Engineering (as discussed), nv-cavity, others
– Optics (Aaronson)
• Error control:
– Threshold theorem, stabilizers, Clifford gates.
– Central idea: How to implement the
algorithms with the noisy reality of … reality?
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6. research areas cont …
Algorithms
– Hilbert spaces, linear algebra, (quantum)
complexity theory
– Factoring, Search, Systems of linear
equations (Ax = b)
– Higher-dimensional models (qutrit, qudit,
interesting?)
– Sampling distributions (QMC, MCMC)
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7. research areas cont …
Programming
– Quantum programming languages, circuit
models, computation models (quantum von
Neumann model, QRAM), lamba calculi
– Compilation: Solovay-Kitaev: realisation of
any Unitary with some universal gate set.
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8. research areas cont …
Information Theory
– Entanglement, How to measure it? What
affect does it have, algorithmically?
– Entropy, is it a good way to look at things?
– (Black holes as QCs? Seth Lloyd)
– (Energy) Teleportation, input energy at A, get
it at B.
– Game Theory, solution to Byzantine Generals
problem
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9. research areas cont …
Cryptography
– Quantum Money, can we make some? Can it
be unforgeable?
– Algorithms to replace RSA? AES? SHA?
(mostly, these are not quantum).
– QKD, (requires classical channel, often
broken)
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10. research areas cont …
“Foils”
– Interesting, adjustments to quantum theory,
or other physics, then consider relevance to
complexity theory and bounds, etc.
– I.e. QC w/ closed time-like curves (if exist,
QC=CC)
– Lends itself to philosophy
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11. Summary
• Almost everything that is classical can be
reconsidered under quantum
• It is fun, get involved if you like!
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