Albert Einstein hated quantum mechanics. He called it "spooky action at a distance" and spent decades trying to prove it was wrong. But Niels Bohr fought back, defending the Copenhagen interpretation, which claimed that quantum reality doesn’t exist until we measure it.
The Bohr-Einstein debates were some of the most legendary arguments in science, filled with clever thought experiments, deep philosophy, and a battle over the nature of reality itself. Did Bohr really defeat Einstein? Or was Einstein’s skepticism a clue that quantum mechanics is still incomplete?
This episode unpacks the greatest physics debate of all time and the experiments that settled the score.

In the classical world, you can measure where something is and how fast it’s moving with perfect accuracy. But in the quantum world? Not a chance.
In 1927, Werner Heisenberg proposed something shocking: the more precisely you measure a particle’s position, the less you can know about its momentum, and vice versa.
This wasn’t a limitation of our tools—it was a fundamental property of nature. The Uncertainty Principle shattered the idea of a predictable universe, proving that at the smallest scales, reality is a game of probabilities, not certainties.
But what does this mean for free will? Does reality truly exist before we observe it? And did Heisenberg’s discovery kill determinism once and for all?

Imagine firing a tiny particle at a barrier with two slits. It should go through one or the other, like a bullet. But in the double-slit experiment, something unbelievable happens.
When no one is watching, particles act like waves, interfering with themselves. But the moment we try to observe which slit they go through, the interference pattern vanishes, and they behave like individual particles. It’s as if electrons know they’re being watched.
This experiment isn’t just a physics puzzle—it’s a philosophical crisis. Does reality only exist when observed? How can something be in two places at once? And what does this mean for our understanding of the universe? This is the experiment that shattered classical physics and forced scientists to rethink reality itself.