• Question: Why do you have to make predictions if you can easily get the data?

    Asked by anon-201342 to Sophia, Sarah, Meirin, George, Emily, Andy on 13 Mar 2019.
    • Photo: Andy Buckley

      Andy Buckley answered on 13 Mar 2019:

      It’s not so easy to get the data! And there will always be aspects that are hard to measure, either because they are very rare or because it’s hard to design “observables” that tell us about the theory. I’d put it the other way around though: we make predictions because we’re trying to understand the world, and *then* we go out and search for data to confirm or deny the theories.

    • Photo: Sarah O'Sullivan

      Sarah O'Sullivan answered on 13 Mar 2019:

      Often you need a prediction to help you develop an experiment so you have a sense of what things you’ll need to measure before you start

    • Photo: George Fulton

      George Fulton answered on 13 Mar 2019:

      Making predictions is important because getting data is expensive 🙂 If we could do our work without experiments then no-one would do experiments. If you can get a model that predicts what happens in real life, then this is really powerful. But with all theories and simulations, experimental data is required to compare and validate these models.

    • Photo: Emily Lewis

      Emily Lewis answered on 13 Mar 2019:

      I can’t easily get the data! Or at least, I can get computer data but not real experimental data.
      I’m looking at reactor designs to see how they might behave in real life. It’s tricky to get experimental information because building a nuclear reactor is expensive, can be dangerous and takes a long time.
      Instead we use a computer simulation, which is less accurate as we make a lot of assumptions, but it helps us get rid of designs that look really wrong!

    • Photo: Sophia Pells

      Sophia Pells answered on 13 Mar 2019:

      Like other people have said it is not always easy to get data. The radioactive isotopes that I am studying are difficult to produce so we don’t get to perform experiments on them very often. I use simulations so we can predict what we will see and try to optimise the experiment so that when we do it for real we get better results.

    • Photo: Meirin Oan Evans

      Meirin Oan Evans answered on 14 Mar 2019:

      Predictions are a crucial part of how science is done. First there’s a theory or hypothesis. This theory is used to make predictions. Then we carry out an experiment. If experimental data all disagree with a theory’s predictions, that theory can be ruled out as not representing reality. If experimental data agree with a theory’s predictions, we can keep using that theory until an experiment disagrees! Experimental data is the most important thing after all, since that’s the real world.