Reductionism Works
Large things are made of smaller things, and if you know what the small things do, you can tell what the large things do. Physicists call this idea reductionism. You might not like it, but it arguably works well.
Reductionism allowed us to understand molecular bonds and chemical elements, atomic fission and fusion, the behavior of the atom’s constituents, and these constituent’s constituents—and who knows what physicists will come up with next.It took some centuries, but thanks to reductionism physicists now have a remarkably simple description for our universe that explains almost everything we observe. According to this description, matter is made of 25 particles, collected in what is known as the standard model of particle physics. The 25 particles interact through four forces: the electromagnetic force, the strong and weak nuclear force, and gravity. And everything else—from chemistry to biology to cosmology—follows from that, at least in principle.
This currently best explanation for the world around us is almost certainly incomplete. There might, for example, be a few more particles to account for dark matter. Something’s fishy with the cosmological constant. And no one understands how gravity works when space-time is strongly curved. But for the following argument these unresolved puzzles do not play a role because we will be concerned only with the structure of the theories we know already.
S. Hossenfelder (B)
Frankfurt Institute for Advanced Studies, Ruth-Moufang-Str. 1, 60438 Frankfurt am Main, Germany
e-mail: sabine.hossenfelder@gmail.com © Springer Nature Switzerland AG 2019
A. Aguirre et al. (eds.), What is Fundamental?, The Frontiers Collection, https://doi.org/10.1007/978- 3-030-11301-8_9
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