Albert Einstein and relativity

If I were to ask a number of people in the street what they think was the most important new theory in physics in the twentieth century, and who has been the greatest physicist, I am fairly sure that – of those able to express an opinion at all – a substantial majority would say that relativity has been the greatest theory, and Einstein the greatest physicist.

Indeed Albert Einstein has probably achieved the remarkable feat of not just becoming the best-known practitioner of any branch of science among the general public, but retaining that position for 85 years, 50 of those years since his death in 1955.

It was in 1905, when he was 26, that Einstein astonished the scientific community by producing four pieces of work of the very highest quality. These included his first paper on relativity, in which he introduced what is now called the special theory of relativity (a term I shall explain in Chapter 3). The three other papers will be referred to in due course. What was astonishing was not just the quality of the work, but that the author was not an academic of note, or even of promise, but was working as a patent inspector after rather a mediocre student career. (A recent pleasantly written biography of Einstein is that of Abraham Pais [1], himself a well-known physicist; Pais gives references to many other accounts of Einstein's life. Another, more recent, biography is that by Fölsing [2].