Greene is the foremost public evangelist for string theory. To him, it is the only game in town for a "Theory of Everything"—a unified framework that merges general relativity (gravity) with quantum mechanics. When asked about problems like the cosmological constant, Greene tends to double down on string theory’s potential.
To the layperson, they are often conflated as ambassadors of "deep time" and "deep space." However, a rigorous analysis reveals a fundamental tension. Greene is the heir to Einstein’s dream of unification, seeking structure through hidden dimensions. Carroll is the heir to the Copenhagen interpreters (though he rejects Copenhagen), seeking clarity in the foundations of quantum mechanics and the philosophy of science. Their divergence offers a roadmap to the current crisis in theoretical physics: the split between the search for unification (Greene) and the search for foundation (Carroll). brian greene sean carroll