What is physics?

Pictured: undergrads, graduate students, staff (not pictured), and faculty (not pictured) get together to learn about the physics of making liquid nitrogen ice cream!

What is physics? You probably think of a high school class about rolling balls down hills. Dictionaries just say it’s the study of matter and energy. But there’s a lot more to it!

The job of a physicist is to invent new contraptions and to discover new laws of the universe. 


In first year college physics, you do study kinematics, the motion of objects, and Newton’s laws. But you also delve into more cool topics, like Einstein’s theory of relativity. The next semester, you study how electricity and magnets work, topics in thermodynamics – the study of heat, energy, and things like entropy – and also get an introduction to quantum mechanics.

But after getting exposed to the basics, physicists have the tools study and build all sorts of awesome things. Here are just a few subfields of physics:

  • Astronomy – planets and black holes and stardust, oh my! (yes, we do have real live Stardust in our department)
  • Biophysics –  studying how molecules and cells move around and interact, and manipulating them to do cool things!
  • Condensed matter physics – working with solids and liquids, including everything from superconductors to ultracold atoms
  • Cosmology – a combination of history and fortune-telling: uncovering the Universe’s past and predicting its future
  • Geophysics – earthquakes, the movement of water in the ocean, the Earth’s magnetic field, and more!
  • Gravity – that thing that’s always pushing down on you
  • Nuclear physics – BOOM
  • Optics – lasers!
  • Particle physics – learning about and smashing together the smallest and most exotic components of the universe, from protons and neutrons to quarks and the “God particle”
  • Quantum information/quantum computers – trying to design computers that are faster and better than anything we have yet
  • String theory – a “theory of everything”

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