Into The Impossible: Rovelli on Free Will, Time, and Physics

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When physics meets philosophy, familiar ideas can suddenly look unstable. Brian Keating's conversation with Carlo Rovelli on Into The Impossible really drives that home. Rovelli, the loop quantum gravity pioneer, challenges something most people take for granted: "It is not true that things inevitably descend into disorder." That's fascinating because we're always told entropy means everything falls apart. But what's his alternative view? He points to nature creating order on its own— frost on glass, sand and stones sorted by the ocean. Even biology is an enormous amount of order created as entropy grows. This connects directly to his ideas about the arrow of time. Right, and Rovelli connects the past, memory, and planning to entropy, but he resists simple stories. The low-entropy early universe remains a mystery. He says neither general relativity, quantum mechanics, nor loop quantum gravity explains that boundary condition. His alternative is provocative though. Low entropy may not be an absolute feature of the universe at all, but a result of coarse graining—the way observers choose variables. As he puts it, "The flow of time is perspectival." What seems universal may partly reflect how minds and measuring systems are built. That same relational view runs through his quantum mechanics interpretation. Rovelli says properties are not absolute, but relative to observers. He even jokes that, in principle, "You, Brian, can exist in a superposition; you can be in Los Angeles and San Francisco simultaneously."

The point isn't magic, but that physics describes relations, not fixed standalone facts. And he extends that to space and time. Contrary to popular shorthand, "To say they are the same is simply nonsense." He rejects the block-universe picture, calling spacetime a process, like the plot of a novel, not a frozen four-dimensional object.

What about irreversibility? That seems crucial here.

Rovelli argues that measurement already requires dissipation in classical mechanics, so the problem of time isn't confined to quantum theory. Recording information, sorting objects, checking pressure—all involve macroscopic processes that don't run backward so neatly. And on free will, his answer is unusually direct: "Freedom does not require the violation of the laws of nature." Deliberation is the ability to consider alternatives and decide, applying to both people and, in a limited sense, even machines.

Speaking of machines, he's cautious about AI but not dismissive. He doesn't think today's large language models are close to human-like creativity, yet he sees no principle that makes thought impossible for machines. He closes with a deeper naturalism: there is "no fundamental distinction between mind and body," or between humans and the rest of nature.

That idea ties together his physics and philosophy—the world is not built from isolated absolutes, but from relationships all the way down.