NEW YORK, NY.- A century ago, Albert Einstein published the general theory of relativity, the crowning achievement of the great physicist’s illustrious career. In celebration of this landmark achievement, the Morgan Library & Museum is presenting a pop-up exhibition from June 28 through October 16 featuring a trio of Einstein items.

The general theory of relativity, published in 1916, expanded on Einstein’s earlier 1905 special theory of relativity and its famous equation E=mc2. The exhibition features a letter written by Einstein to the noted astronomer Erwin Finlay Freundlich, who was attempting to confirm the general theory through astronomical observations. One of twenty-five such letters in the Morgan’s collection, Einstein questions Freundlich’s methods, which were ultimately unsuccessful.

In addition to the letter, the pop-up show includes a very rare written summation of the special theory in the scientist’s own hand. Also featured is a photograph inscribed by Einstein in 1921 while he was in the United States to deliver speeches and lectures, and to raise money for the newly founded Hebrew University in Jerusalem.

In this centenary year scientists are yet again confirming Einstein’s general theory. Just days ago U.S. researchers reported observations that detected gravitational waves caused by the collision between two black holes. This is the second time in human history that gravitational waves have been detected, proving definitely that Einstein’s June 1916 presentation of the general theory of relativity has passed the test.