More than usual, there was a line of students waiting to speak to Dr. Drew Baden, a professor of physics at the University of Maryland, after his lecture. The engineering students who are required to take general physics were showing greater enthusiasm than normal. It was a bit odd, however, for Dr. Baden had prefaced this series of lectures on special relativity as something that the engineering students would seldomly–if ever–use in their work. And yet, more than ever, the students were invigorated.
As Dr. Baden taught special relativity over the course of a few weeks, the students were amazed. Perhaps, it was because of the seemingly strange general results of special relativity, time dilation and length contraction. That is, time passes at different rates for different observers moving relative to each other, and moving rods contract in length. There was bewilderment at the not-so-paradoxical twin paradox. But still, what really may have captured the students were the very thoughts of Albert Einstein. Dr. Baden drew on the chalkboard the thought experiments Einstein used on his way to special relativity. An observer watches a train go by as a man in the train sends a light beam to a mirror in the train. Each man tracks the path of light and makes his calculation. The results are stunning. Indeed, what wonderful thoughts Einstein had.
There is the apparent ease with which Einstein rescued physics from fundamental problems as he ushered in a new kinematics based on two postulates alone. He relied little on experiments and leaned into rationalism to formulate his grand theory. What deep faith he had in natural harmony to craft a theory that defied our everyday experience.
“Subtle is the Lord, Malicious He is not,” Einstein said. “Nature hides her secret because of her essential loftiness, not by means of ruse.” Einstein, a Jew, was not observant, and yet, he lived by a deep faith. So much so, that he spent the last few decades of his life as an outsider in the physics community. Einstein had profound qualms with the latest theory, quantum mechanics, a theory that he himself had helped discover.
He did not believe quantum mechanics was complete. The theory did away with causality. Nature was not deterministic, but probabilistic. In other words, the theory said one could not know with certainty physical quantities. One can only find how probable it is to measure a physical quantity. Dr. Baden told his students quantum mechanics was not so much a theory of nature, but a theory of what we can know about nature.
To Einstein, this was unacceptable. “Subtle is the Lord, Malicious He is not.” Einstein acknowledged the great success of quantum mechanics, but believed there was something more to be discovered. Something that would rescue causality and the inner harmony of nature. The lonely man of faith tried to discover a sweeping causal “theory of everything” until his death in 1955. But he could not find it.
In his lonely struggle, Einstein compared himself to the biblical figure Job in a letter to physicist Niels Bohr: “There was a general shaking of heads concerning the words of candidate Jobs.”
In the Book of Job, Job is a righteous, G-d fearing man with a happy life. But he loses everything he loves and suffers greatly. Like Job, Einstein must have wondered why? His life was devoted to discovering nature’s immutable laws, and yet, now he was, in his words, “an ostrich who forever buries its head in the relativistic sand in order not to face the evil quanta.” Alas, there may be things we (even Einstein) cannot quite understand for we cannot see or know as G-d does.
And yet, Einstein’s legacy endures. A century and a score later, students still marvel at his wonderful theory of relativity, not just for its stunning results, but for its display of one of the greatest achievements in the history of human thought.
