ELI5: Explain Like I'm 5
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Covariant Hamiltonian field theory

Covariant Hamiltonian Field Theory is a type of physics that studies the way in which particles interact with each other. It looks at how different particles can change their speed or direction when they get close to each other. The theory uses mathematics to calculate how much the particles change their speed or direction. By understanding the mathematics, physicists can figure out how particles behave when they come close to each other.