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physical qubits

Last edited: August 8, 2025

We will leverage atoms as qubits. So, how do we isolate a qubit from an atom? We will leverage electrons.

We will select the lowest energy state as the base state; as there maybe multiple ground states, we will choose \(|u\big>\) and \(|d\big>\) from two of the states.

physics

Last edited: August 8, 2025

physics is the act of explaining what we see in terms of solving for the “unseen”. For an explanation to be good, it needs to be testable.

How exactly does physics work?

“classical results”

  • Newton’s laws
  • Maxwell’s equations
  • General relativity

“quantum theory”

A new model that actually allows particle inference.

Pineau 2006

Last edited: August 8, 2025

(Pineau, Gordon, and Thrun 2006)

PBVI

One-Liner

“If we can avoid the curse of history, the curse of dimensionality wouldn’t be a problem”.

Basically - most POMDP problems don’t reach much of the belief simplex. So, can we concetrate planning on more probable beliefs.

Novelty

  1. trajectory based approach to select beliefs
  2. belief set is fixed through layers: each backup results in the same number of layers

Notable Methods

PBVI

Key Figs

New Concepts

Notes

pipe

Last edited: August 8, 2025

pipe chains the STDOUT of one command and put it to the STDIN of another command. Typically, we want to do pipe per direction.

command pipelines

  1. span two child processes
  2. create a pipe to allow the two processes to communicate
  3. connect the first child’s STDOUT to the pipe + the second child’s STDIN to the pipe

pipe()

pipe() gives us back two file descriptors, such that whatever is written to one can be read from another.

Pipes are so bad

Last edited: August 8, 2025

I, for sure, spend equal if not time writing the data flywheel code compared to architectural changes.

This has been bugging me for awhile, but I haven’t had time to sit down and write about it until now. In my mind there are three things that makes coming up with a good take about this (and also implementing it) hard:

  1. This may be a problem that’s solved in much of the frontier labs (I would argue more because of workflow optimizations that sidestep the problem, see below)
  2. The “solution” to the problem also seem extremely person-dependent, so it seems hard to make an overall suggestion.
  3. Many people write it off as “necessary engineering”

I don’t purport to have a solution to the pipes problem here, but I want to spend a little time now to reflect about what I have been thinking about while spending days at the office writing pipes.