William Phillips was given this slide rule in 1963, just before his 15th birthday when he was going to study physics at school. He used it for calculations for his homework and exams. He recalls one time when he had made a mistake in a task even though he understood the question. He had added it up wrong, and told the teacher he had trusted the slide rule but that it couldn't do addition, only multiplication and division. The teacher told him to try to design a slide rule that could do addition. This prompted Phillips to examine how the slide rule worked. It can be used for multiplication since the scale is logarithmic, but with a linear scale it could also be used for addition. He presented his idea to the teacher. It was never implemented in practice, but his teacher was impressed.
When Phillips started at university, he found a more sophisticated slide rule, and he also had access to larger mechanical calculators and eventually an electronic one. When pocket calculators were introduced, this changed the potential entirely.
William Phillips donated the slide rule to the Nobel Prize Museum in 2024.
When William Phillips was eleven, his parents gave him this stopwatch. He wanted it in order to perform simple experiments, such as measuring the time it took for pendulums and swings to oscillate, and objects to fall to the ground. He also used the stopwatch to time runners.
As a physicist, Phillips later developed methods for cooling atoms with laser beams. This method made it possible to create even more precise atomic clocks. Their uncertainty is one second per 300 million years.
William Phillips donated the stopwatch to the Nobel Prize Museum in 2024.
