###### By Jonny Lupsha, Wondrium Staff Writer

## Einstein’s greatest failure may still prove to be a triumph, *Live Science* reported. Theoretical physicists have taken up his cause of looking for a theory that unifies all known forces of nature. Einstein never finished a unified field theory.

According to *Live Science*, Einstein’s own quixotic quest may yet soon come to pass. “In his waning years, Albert Einstein spent his time tilting at windmills, trying to unify all the forces of nature,” the article said. “He died disappointed, and his attempt would go down in history as his biggest failure. But Einstein’s failed dream could ultimately become his ultimate triumph, as a small group of theoretical physicists rework his old ideas.”

Unified field theory is a complicated idea, but considering the relationship between electricity and magnetism—once thought to be separate phenomena—is a good example of unifying different scientific ideas. Einstein passed away with many unification questions unanswered.

#### Building on Earlier Ideas

Albert Einstein wasn’t the first scientist to try to build a unified field theory. A German physicist and mathematician named Hermann Weyl came first, though he and Einstein were reportedly in contact for much of Weyl’s work on the theory.

“From Weyl’s perspective, there was really one central challenge that made it so hard to combine general relativity and electromagnetism into a single unified field theory,” said Dr. Dan Hooper, Senior Scientist and the Head of the Theoretical Astrophysics Group at the Fermi National Accelerator Laboratory. “This challenge basically boiled down to the fact that general relativity is a theory of geometry, while electromagnetism is not.”

Dr. Hooper said that Weyl proposed a version of non-Euclidean geometry that was mathematically sound, but complicated and tenuous when it came to physics. His work and that of mathematician Theodor Kaluza inspired Einstein’s continued pursuit of the theory.

“What [Kaluza] proposed was a unified field theory in which the space and time of our universe isn’t four-dimensional, but that instead consists of five dimensions,” he said. “Despite the fact that there were significant problems with the five-dimensional theory, Einstein seems to have liked it a great deal. Einstein continued to work on this theory not because he thought it was a viable unified field theory, but because he thought that it might lead to something more promising.”

**The Stubborn Einstein**

Einstein began working towards a unified field theory in the early 1920s. He passed away 30 years later, in 1955. His isolation in the scientific community and his occasionally old-fashioned ideas hindered his efforts.

“Quantum physics was developing rapidly, and that seemed to be occupying the bulk of the field’s attention during this time,” Dr. Hooper said. “Einstein was deeply unhappy with the developments occurring in quantum theory, and he became only more opposed to it as quantum mechanics continued to develop.”

Einstein was said to have wished for a return to determinism and scientific realism in the quantum world, and he embraced an older theory of electromagnetism—Maxwell’s classic theory—as part of his unification study even after it had been replaced by quantum theory. Dr. Hooper said that Einstein had hoped that quantum mechanics was just a fad, and so he largely ignored it.

“In the years that followed, Einstein continued to explore different approaches in his search for a unified field theory,” he said. “But none of these approaches ever even attempted to incorporate quantum mechanics. Over three decades, Einstein’s fixation on classical field theories, and his rejection of quantum mechanics, increasingly isolated him from the larger physics community.”

When Einstein died, he was essentially no closer to a unified field theory than he had been when he began working on it 30 years earlier. With the scientific understanding that has been developed in the last 60 years, scientists may soon help him get there.

Edited by Angela Shoemaker, Wondrium Daily

Dr. Dan Hooper contributed to this article. Dr. Hooper is a senior scientist and the head of the Theoretical Astrophysics Group at the Fermi National Accelerator Laboratory (Fermilab). He is also Associate Professor of Astronomy and Astrophysics at the University of Chicago. Dr. Hooper received his PhD in Physics from the University of Wisconsin–Madison.