Many students and administrators at Pasadena City College may not know that Albert Einstein, the world-famous theoretical physicist, visited the college on February 26, 1931, to dedicate the new observatory. He and his wife, Elsa, lived in Pasadena during Caltech's winter quarters of 1931, 1932, and 1933.

"Here in Pasadena it is like paradise," said Einstein. "Always sunshine and clear air, gardens with palms and pepper trees and friendly people who smile at one and ask for autographs."

Einstein's ideas changed the world and the way we understand it. His 1921 Nobel Prize-winning Theory of the Photoelectric Effect was far ahead of its time. It helped scientists and engineers develop modern inventions that we take for granted today, such as CD players and television.

2005 marks the centennial of 1905, Einstein's "miracle year." In that year, Einstein, a 26-year-old patent clerk living in Switzerland, published four papers about Brownian motion, the photoelectric effect, and relativity. In these papers he proved the existence of atoms, presented his Special Theory of Relativity, and put quantum theory on its feet. In that year, Einstein also devised an equation that made him famous: E=mc². He later described 1905 as the year that "a storm broke loose in my mind."

"Einstein was a very modest man," said Martin Klein, senior editor of "The Collected Papers of Albert Einstein" and a guest speaker at Caltech's Einstein Centennial lecture series. "He taught himself because he felt college was too much like high school. He read mathematical physics at his own pace to feed his 'intellectual digestion,' as he put it."

Einstein is considered one of the most significant people of the 20th century. In January 1933, Einstein and Pasadena stood together on the world stage as he made a national radio broadcast from the Pasadena Civic Auditorium calling for peaceful relations with Germany. A few days later Adolf Hitler became chancellor and made it clear that Einstein would not be welcomed by the Third Reich. Einstein never set foot in his homeland again.

"Einstein as a person holds relevance to the troubling times of today," said Michael Kardos, producer of the documentary "When Einstein Lived in Pasadena" (2004).

Einstein was a devout pacifist his entire life. He despised militarism and the use of force, although he later recognized that in some situations, there is no alternative but to fight for peace.

An exhibit at the Skirball Cultural Center in Los Angeles celebrated Einstein's centennial from January to May this year. A plaque there read: "While watching a German military parade in the 1880s with his parents, young Albert became terrified by the almost mechanical movements of the soldiers who seemed to have no minds of their own. His parents had to promise their frightened son he would never have to become a soldier. He denounced World War I, but the rise of Nazism made him realize force was sometimes painfully necessary."

Concerned the Nazis were trying to build an atomic bomb, Einstein wrote a letter to President Roosevelt on August 2, 1939, urging him to find a source of uranium and fund research in nuclear fission. Six years later the bomb was dropped on civilians in Hiroshima and Nagasaki, and Einstein openly regretted his action. He called the letter to Roosevelt "the greatest mistake of my life.

"I am willing to fight for peace," said Einstein. "Is it not better for a man to die for a cause in which he believes, such as peace, than to suffer for a cause in which he does not believe, such as war?"

Just before his first visit to Pasadena on December 31, 1930, Einstein said that if just two percent of all soldiers refused to serve in their respective armies, governments would be powerless in waging wars. Prisons would overflow and soldier reserves would dwindle.

"Einstein's 'two percent solution,' as it came to be known, seemed like a simple and noble approach to stopping the madness of war to him," said Kardos. "But to a whole lot of other folks, it was tantamount to sedition."

Because of Einstein's opposition to war, J. Edgar Hoover and the FBI kept a file on him that ran 1,400 pages long.

"In the context of the issues facing us today, Einstein would probably be right at home with the protests against the war in Iraq," said Kardos. "Surely he would have condemned Hussein and the Baath Party. But it's just as likely that he would've decried the pre-emptive, unilateral invasion of Iraq based upon specious evidence and arguments."

Einstein died on April 18, 1955, soon after a blood vessel burst near his heart. When asked if he wanted to undergo surgery, he refused, saying, "I want to go when I want to go. It is tasteless to prolong life artificially. I have done my share. It is time to go. I will do it elegantly."

Caltech's Einstein Centennial Lecture Series continues on Sept. 27 and Nov. 16, 2005, with speakers Jurgen Renn and Kip Thorne, respectively. For more information, call (626) 395-4652.