• Question: Professor Jeff Forshaw reckons that at a professional level, experimental data for particle physics is much more reliable than theorical calculations in terms of accuracy. Are you also of this opinion?

    Asked by jessthechemist to Chris, Josh, Rebecca, Rob, Susan on 19 Jun 2015.
    • Photo: Susan Cartwright

      Susan Cartwright answered on 19 Jun 2015:


      Yes, because the way that we do calculations in particle physics, called perturbation theory, is always an approximation: it is not possible to do an exact calculation using the methods that we use (and we don’t have any other methods!).

      Also, of course, the data represent reality, whereas the calculations might not. We used to do calculations assuming neutrinos were massless, and that turned out to be wrong, so the calculations were using a flawed assumption.

      Jeff’s a theorist. It’s very good of him to say this!

    • Photo: Rebecca Dewey

      Rebecca Dewey answered on 19 Jun 2015:


      I would agree with anything Jeff says. He was my favourite lecturer when I studied physics at Manchester! 🙂 *swoon*

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