3 Things Einstein Got Wrong


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Look, nobody's perfect — not even Einstein. "In comparison to everything he accomplished, Einstein didn't make that many mistakes," says physicist Dan Hooper, Ph.D. in his course for The Great Courses Plus. "But he did definitely reach wrong conclusions from time to time, and some of these conclusions were very wrong indeed." Many of his biggest blunders came not in being wrong, but in simply not going far enough when he was right. For some things, he realized mere years later that he had missed the mark, but others haven't been overturned until recently. Learn about three of them here, then take a deeper dive in "What Einstein Got Wrong" from The Great Courses Plus.

Black Holes

In 1915, just months after Einstein published one of the biggest achievements of 20th-century physics — his general theory of relativity, which said that gravity is actually a curvature of space that occurs in the presence of matter and energy — a fellow German physicist named Karl Schwarz­schild used his equations to model the geometry of space surrounding a star. Einstein, while impressed, was also flummoxed: those models showed that if you compressed a star's mass into a small enough space, the laws of nature would break down.

Of course, we now know that's the case: a black hole contains what physicists call a singularity, a place where density and gravity reach infinity. In fact, it was that same year that physicist J. Robert Oppenheimer and his student Hartland S. Snyder showed that this precise thing happened to massive stars all the time.

The Expansion of the Universe

Ever make a discovery so universe-shattering that even you can't believe it's true? Yeah, us either. But for Einstein, this was a recurring problem. When he applied the equations in his general theory of relativity to the whole universe, it said something that didn't sit right with him: the universe had to be either expanding or contracting. At the time, everyone "knew" we lived in a static, unchanging universe. Either his equations upended the knowledge of an entire field of science, or his equations were wrong. He went with the latter, and added a symbol — Λ, or lambda — now known as the cosmological constant. It put a stop to any expanding or contracting that the equations might be hinting at.

Well, fast forward to 1929, and some new observations show that — oops! — the universe is actually expanding. Einstein is famously quoted as saying that the cosmological constant was his "biggest blunder" (though the truth of that is sketchy). Physicists have since repurposed the cosmological constant to refer to the force that's making the universe expand, so buck up, Al. It wasn't so useless after all.

Quantum Entanglement

When it comes to quantum mechanics, Einstein was both one of its biggest contributors and one of its biggest critics. He discovered the existence of photons (particles, or "quanta," of light) and the idea that light behaved as both a particle and a wave way back 1905. That was decades before Werner Heisenberg and Erwin Schrödinger's first quantum theory of physics, which introduced the mind-bending concepts the theory is now so famous for: that particles can exist in two states at once, that observation itself can affect a particle's behavior, and if you know the momentum of a particle you can't know its location (and vice versa).

Einstein didn't think much of the new theory, and, along with physicists Boris Podolsky and Nathan Rosen, proved it "wrong" by using math to show that you could entangle two particles so that the behavior of one affected the behavior of another, no matter where it was in space. But that means information could travel faster than the speed of light, and according to his own special theory of relativity, that was impossible. This was dubbed the EPR paradox, after the three scientists who posed it. It wasn't until after Einstein's death that a physicist named John Stewart Bell resolved it with a test that scientists are still using to show evidence of quantum entanglement today.

There's more that Einstein got wrong (and right!), and you can learn it all in the course "What Einstein Got Wrong" on The Great Courses Plus. Over 12 lectures, University of Chicago associate professor and Fermilab senior scientist Dan Hooper, Ph.D. delves into the concepts Einstein championed and the ones he railed against, giving a full overview of the most important principles in physics along the way. You can take the entire course when you sign up for a free trial here.

Official Trailer: What Einstein Got Wrong

Written by Ashley Hamer May 31, 2018