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Experimentalists and theorists in action

The thinkers and the makers

Reading the pages about CERN, you may have noticed that physicists are often referred to either as ‘theorists’ or ‘experimentalists’. This division is not particular to CERN, as at any university or physics laboratory you would find the same distinction.

What is the difference between theoretical and experimental physicists? To be fair, we have asked both of them...

An experimentalist’s view:
Patrick Janot, from the CMS experiment

“... Theorists often think they do create physics with their theory, experimentalists often think they do discover or invent physics with their experiments, accelerator physicists often think they make it possible with their instruments, and they all think that the other categories exist only to provide them with the technicalities they either do not want - or are not able - to work out: long but straightforward calculations, subtle but repetitive measurements, powerful but dirty tools ... ”

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A theorist’s view:
Alvaro de Rújula, from the Theory Unit

“... Theoretical physicists are rather typical scientists. If you imagine them as absent-minded, egg-headed, bizarre characters scratching their chins while deeply engaged in thought... Well, most of the time you'd be right...”

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