In 1905, Albert Einstein published a series of papers that constitute an unprecedented display of creativity. The paper Einstein (1905) published in June of this annus mirabilis deals with the theory of relativity, a work that eventually brought Einstein rock-star fame. The first sentence of the essay makes an aesthetic observation: “It is known that Maxwell's electrodynamics, as usually understood at the present time, when applied to moving bodies, leads to asymmetries which do not appear to be inherent in the phenomena” (italics added). Einstein discusses the meaning of this asymmetry with an example from the theory of electromagnetism. He observes that a magnet in motion relative to a wire loop produces an electrical current in the wire. According to Maxwell's theory, different equations apply when the magnet moves and the wire is stationary and vice versa. In one case, the magnet is moving with respect to the ether (a universal static substance that acts as the medium for transmission of light) and in the other, the magnet is at rest with respect to the ether. This asymmetry was unacceptable to Einstein. If the current is the same in both cases, then one is looking at the same phenomenon from different perspectives, or from different reference frames, thus making the idea of an ether superfluous. McCullagh's prediction (see the quotation on page 110) of an unexpected, simple and beautiful ether is perhaps fulfilled; non-existence is the ultimate simplicity. The new theory is based on two simple postulates:

From this starting point, as simple as it is audacious, Einstein leads us through a path of impeccable logic that culminates in the notion that time, represented by the ticking of a wristwatch, is not an absolute phenomenon.

It is remarkable that the equations that Einstein derives existed before his work. In 1895, the Dutch physicist Hendrik A. Lorentz, in order to explain some experiments by Michelson and Morley wrote a set of equations (identical to Einstein's) in which time appeared as a mathematical variable that depended on velocity and position.