What master's thesis could I write about AI safety?

In general, you could identify a specific open problem that interests you, and try to contribute to a solution. You might find some ideas for areas to explore in the resources we link below.

Some resources that might help you think about this are:

One approach would be to identify a specific open problem that interests you and try to contribute to a solution. For instance:

For a broad overview of the field as a whole, you could explore the Map of AI Existential Safety.