Physics will be unified again as it has been before; the obstacle is that relativity and quantum mechanics already explain almost everything we can measure.

Drawn from what Terence Tao said

What these subjects mean

physics Fundamental physics: unification, relativity and quantum mechanics, and whether string theory is still the candidate.

quantum mechanics The theory itself and the arguments about what it means -- measurement, collapse, and whether nature is locally causal.

What Terence Tao actually said

Do you hold this korrent?Do you also believe this?

Shared subject first, then similar wording. They may agree or disagree.