VMany researchers get their best ideas while walking or sleeping, when the subconscious is free to think about a problem. The physicist Steven Weinberg had his greatest idea, which would revolutionize particle physics and bring him the Nobel Prize, when he drove to his work place, the Massachusetts Institute of Technology (MIT) in Boston, in his red Chevrolet Camaro in 1967.
Weinberg had been brooding for a long time about how the four existing natural forces – the strong nuclear force, the weak and the electromagnetic force as well as gravitation – could be reconciled despite their different appearances. He was convinced that the forces originally acted like a single elemental force and only decoupled after the Big Bang, in a later phase of the universe.
The saving trick
Behind the wheel of his sports car, it suddenly became clear to Weinberg that at least two natural forces had an amazing mathematical commonality. This made it possible to describe the electromagnetic interaction that works between charged particles and the weak force that plays a role in radioactive decay with a uniform set of formulas. When he got to the office, he wrote his thoughts down in a two and a half page article that appeared in the prestigious Physical Review Letters. But his ideas initially met with little interest. But that changed when it was found that two other theorists – Sheldon Glashow and Abdus Salam – were working on the same problem.
The three physicists joined forces and developed a theory that unified the weak and the electromagnetic force, which they dubbed the electroweak interaction. This brought them a great deal closer to standardizing the forces of nature. However, your theory had several flaws: it required the existence of exchange particles, which should correspond to the photons of the electromagnetic force, only that they should carry mass. There should also be weak processes (neutral currents) in which the charge of the partners involved did not change. This was inconsistent with the emerging idea that matter is made up of three elementary quarks.
In 1970, Glashow unceremoniously “invented” a particle of matter that – unlike the three quarks known up to that point – was supposed to arise in weak reactions. When this building block – the charm quark – was actually discovered in 1974, and in 1983 the outstanding exchange particles of the electroweak interaction – the W and Z bosons – saw the light of elementary particle physics, the new theory finally found its way into textbooks. Today it forms a pillar of the standard model of particle physics, the world model, which describes the structure of matter. Four years earlier, Glashow, Salam and Weinberg had received the Nobel Prize in Physics.
The universe in three minutes
In the 1980s, Weinberg, who was born in New York and worked at the University of California at Berkeley, MIT and Harvard University, and since 1982 headed the theory group at the University of Austin in Texas, also tried the electroweak force and standardize the strong nuclear power – but without much success. Weinberg, an avowed atheist, from then on dealt increasingly with questions of astronomy and astrophysics.
Weinberg, whose need was to explain difficult topics in a generally understandable way in addition to the actual research, is likely to have become known to a wide audience primarily through his popular science book “The First Three Minutes”. In it he describes the development of the universe from the point of view of particle and astrophysics. Steven Weinberg, who has received many awards, has spoken out on political and social issues even in old age. At the end of last week, it became known that the great physicist died in Austin at the age of 88.