• Question: can we see antimatter?

    Asked by leggy to Jackie, Michele, Oliver, Vicky, Yelong on 10 Mar 2015.
    • Photo: Michele Faucci Giannelli

      Michele Faucci Giannelli answered on 10 Mar 2015:

      We can measure antimatter in several ways, for example the momentum of a positron can be measured in a magnetic field in the same way an electron is measured. We can also use the annihilation of antiparticles in matter to study other properties such as their energy. As for any fundamental particle, it is not possible to see them either because they do not have a size (which is the meaning of being fundamental) or are very very small, like the anti-proton atoms produced at CERN.

    • Photo: Vicky Bayliss

      Vicky Bayliss answered on 12 Mar 2015:

      On a more philosophical level, if you could see antimatter – then it wouldn’t have taken scientists so long to discover it, so it wouldn’t be caller antimatter, because it would just be part and parcel of matter that we’ve known about all along…

    • Photo: Jaclyn Bell

      Jaclyn Bell answered on 13 Mar 2015:

      Exactly. Anti-matter is made up of anti-particles, like the positron whose matter partner is the electron. The positron has a “+” charge and the electron has a “-” charge. We can detect anti-matter and know that particles like positrons exist using particle colliders. In fact, I just looked on Cern’s website to see when the positron was detected and they say that matter and antimatter are like the solutions of x^2=4. One solution (the common one that everyone gives) is +2 but there is also another solution… -2. Here we can think of +2 as being like our matter particle and -2 like the antimatter particle. Oh and the positron was first seen in a cloud chamber in 1932!

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