What are some risks from (a) highly open and widely available AI systems, and (b)from tight control over AI by a narrow group?
More open AI models increase risks of bottom-up misuse, where members of the general public leverage the technology to pursue negative outcomes. The more people who can access advanced AIs, the more likely someone will use them harmfully.
More tightly controlled powerful AIs increase risks of top-down misuse by government officials and elites. AIs controlled by a small group could be used to lock in their values without considering humanity's interests broadly.
What is an AI singleton? What factors make AI singleton scenarios more or less likely?
An AI singleton is an AI that gains decisive and lasting power over all other AIs and humans. Factors making it more likely include a monopoly over AI development, a fast takeoff, and incentives to capture power. Decentralized development makes it less likely.