That's a very common belief, and it makes sense why people think that! However, it's actually not correct.

Albert Einstein was awarded the 1921 Nobel Prize in Physics, but it was officially **"for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect."**

### So, Why Not for Relativity?

At the time, his theories of special and general relativity were still considered too controversial and unproven by many in the scientific establishment. The Nobel Committee prefers to award prizes for discoveries that have been confirmed by concrete, experimental evidence.

1.  **Too Revolutionary:** Relativity completely overturned Newtonian physics, which had been the standard for over 200 years. Many scientists were not yet ready to accept such a radical shift.
2.  **"Lack" of Proof:** While Arthur Eddington's 1919 expedition to observe a solar eclipse had provided strong evidence for general relativity, the results were still being debated.
3.  **A "Safer" Choice:** In contrast, Einstein's 1905 explanation of the photoelectric effect had been decisively confirmed by the experimental work of Robert Millikan. It was a specific, undeniable contribution that explained a puzzling phenomenon and was foundational to the new field of quantum mechanics.

In a way, the Nobel Committee chose his "lesser" but more easily proven work over his most famous, but still contentious, masterpiece.

**The irony?** Einstein's work on the photoelectric effect was crucial for establishing quantum theory, a field he famously argued with for the rest of his life, stating, "God does not play dice."
