• Question: Edoardo - so your models can help us to observe or make sense of what we observe in space?

    Asked by tulloche to Edoardo on 14 Nov 2019.
    • Photo: Edoardo Vescovi

      Edoardo Vescovi answered on 14 Nov 2019: last edited 14 Nov 2019 8:09 pm

      My research is essentially theoretical and has not to do with experiments or models that describe nature. Instead, the focus shifts to simpler models of fictitious universes that can be completely understood and solved, given little information on the particles in them. The story doesn’t begin with the outcome of an experiment and ends with tweaking the model accordingly — as the scientific method says — but the other way around. We choose particles and interactions, then calculate the result of an imaginary experiment. It’s imaginary because on a scratchpad.
      The reason is that these models are far easier than nature, more symmetric, have less numbers to adjust (like masses and electric charges). Simplicity means that many quantities are calculated without approximations or measurements. The dream in the long run is to use some calculations and techniques to say something — even not with high precision — on the behaviour of real particles and their collisions.
      A bit more if this is still “bluffing”.
      — Which force? My toy models contain point-like particles similar to photons and gluons of the real-world Standard Model (https://en.wikipedia.org/wiki/Standard_Model#/media/File:Standard_Model_of_Elementary_Particles.svg). These particles carry the electric-magnetic force and the force forming atomic nuclei in the real world. I’d say that mine are pretty much the same, except that they do not form atoms.
      — How strong the force? In my toy models, the force intensity is controlled by a number, called “coupling constant”, which can be seen as a cousin of the real-world electric charge. In the real world the electric charge has fixed value, in my fictitious universe the coupling constant is a handle to turn up and down as you like. We’re not after matching calculations and experimental data after all.
      — Which matter particles? Ordinary matter is made of quarks and leptons (see link again) and similar particles are inserted in my models too, in variable number though.
      — All calculations (of collisions, energies between particles etc.) are done on paper and computer. We use different calculational methods (which involve approximations — or not) depending on the value of the coupling constant (small and large — or a medium number close to 1).
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