Quantum hadrodynamics

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Quantum hadrodynamics is an effective field theory pertaining to interactions between hadrons, that is, hadron-hadron interactions or the inter-hadron force. It is "a framework for describing the nuclear many-body problem as a relativistic system of baryons and mesons". [1] Quantum hadrodynamics is closely related and partly derived from quantum chromodynamics, which is the theory of interactions between quarks and gluons that bind them together to form hadrons, via the strong force.

An important phenomenon in quantum hadrodynamics is the nuclear force, or residual strong force. It is the force operating between those hadrons which are nucleonsprotons and neutrons – as it binds them together to form the atomic nucleus. The bosons which mediate the nuclear force are three types of mesons: pions, rho mesons and omega mesons. Since mesons are themselves hadrons, quantum hadrodynamics also deals with the interaction between the carriers of the nuclear force itself, alongside the nucleons bound by it. The hadrodynamic force keeps nuclei bound, against the electrodynamic force which operates to break them apart (due to the mutual repulsion between protons in the nucleus).

Quantum hadrodynamics, dealing with the nuclear force and its mediating mesons, can be compared to other quantum field theories which describe fundamental forces and their associated bosons: quantum chromodynamics, dealing with the strong interaction and gluons; quantum electrodynamics, dealing with electromagnetism and photons; quantum flavordynamics, dealing with the weak interaction and W and Z bosons.

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Elementary particle Subatomic particle having no known substructure

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Gluon Elementary particle that mediates the strong force

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Nucleon Particle that makes up the atomic nucleus (proton or neutron)

In physics and chemistry, a nucleon is either a proton or a neutron, considered in its role as a component of an atomic nucleus. The number of nucleons in a nucleus defines the atom's mass number.

Quark Elementary particle

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Quantum chromodynamics Theory of the strong nuclear interactions

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Strong interaction Force binding particles within hadrons

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A timeline of atomic and subatomic physics.

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Annihilation Collision of a particle and its antiparticle

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Gauge boson Elementary particle

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Exotic hadron Subatomic particles consisting of quarks and gluons

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Nuclear force Force that acts between the protons and neutrons of atoms

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Atomic nucleus Core of the atom; composed of bound nucleons (protons and neutrons)

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In particle physics, a boson ( ) is a subatomic particle whose spin quantum number has an integer value. Bosons form one of the two fundamental classes of subatomic particle, the other being fermions, which have odd half-integer spin. Every observed subatomic particle is either a boson or a fermion.

History of subatomic physics

The idea that matter consists of smaller particles and that there exists a limited number of sorts of primary, smallest particles in nature has existed in natural philosophy at least since the 6th century BC. Such ideas gained physical credibility beginning in the 19th century, but the concept of "elementary particle" underwent some changes in its meaning: notably, modern physics no longer deems elementary particles indestructible. Even elementary particles can decay or collide destructively; they can cease to exist and create (other) particles in result.

References

  1. Serot, Brian D.; Walecka, John Dirk (1997). "Recent Progress in Quantum Hadrodynamics". International Journal of Modern Physics E. 06 (4): 515–631. arXiv: nucl-th/9701058 . Bibcode:1997IJMPE...6..515S. doi:10.1142/S0218301397000299. S2CID   119417340.