How big are the commitments here? I’m having trouble finding actual dollar amounts. Does this actually represent an infusion of money into these SMR efforts, or are these “commitments” tied to so many missable targets that it’s actually meaningless?

Oklo in particular seems to be total vaporware, I can’t find a single technical picture anywhere of anything this company’s reactor is seeking to do. They seem to raise money based on a rendering of a ski lodge.

A huge, concrete investment in TerraPower would be more interesting, but as a molten salt SMR which has never been built, this also looks extremely non-committal.

SMRs in general seem like a dead end, we’ve heard about them for decades and they don’t seem to be any closer to making nuclear power buildouts less expensive.

Everything that makes proven nuclear power plant design expensive seems to revolve around the same drivers of expense for all long-term construction: large up front capital requirements, changing regulations, failure to predict setbacks, and pervasive lawsuits. SMRs purport to tackle a couple of these (shorter-term builds, fewer setbacks), at the cost of considerable efficiency, but so far this seems like an inferior alternative to “just get better at building proven nuclear plant designs”.

Many of the levels in that game take place on tiny planetoids with spherical surfaces and central gravity. "Spherical" sells it short, there were some truly wild topologies around which Mario could run and jump.

It's an elegant rendering trick, but if their worlds are represented as a torus, then I expect this would make rotation on a spherical globe view unintuitive.

One example of this: I would expect each location would not have a single antipode (opposite coordinate) but would instead have three. If you were to start at location A, rotate travel 180 degrees along the latitudinal axis to location B, then 180 degrees around the longitudinal axis... on a sphere you would expect to be back at location A, albeit upside down. But on a torus, you are in a completely different location, which is the 'C' antipode. Rotating 180 degrees latitudinally from here will bring you to point D, the last of the antipode set.

Wonderful write-up of attempting to tackle this problem. I believe there must be a significant number of people who have played both Minecraft and Super Mario Galaxy, and had something like this sequence of thoughts - although you have followed it all the way to an actual demonstration, and written up your thoughts along the way so clearly.

The vertical distortion is the biggest issue IMO, there are a few reasonably satisfying ways to approach the horizontal tiling of each “shell”. For example, you can make your world a donut instead of a sphere, and now you have a perfect grid at each level! Of course, this introduces a level of distortion between the interior and exterior, so you also twist the donut once, and now you’ve both solved your distortion problem and invented the stellarator fusion device.

Rust uses the traits “Send” and “Sync” to encode this information, there is a lot of special tooling in the compiler around these.

A type is “Send” if it can be moved from one thread to another, it is “Sync” if it can be simultaneously accessed from multiple threads.

These traits are automatically applied whenever the compiler knows it is safe to do so. In cases where automatic application is not possible, the developer can explicitly declare a type to have these traits, but doing so is unsafe (requires the ‘unsafe’ keyword and everything that entails).

You can read more at rustinomicon, if you are interested: https://doc.rust-lang.org/nomicon/send-and-sync.html