Subatomic particle
Particles smaller than atoms, studied in particle physics.
A subatomic particle is a particle smaller than an atom. According to the Standard Model of particle physics, subatomic particles can be composite particles, such as protons and neutrons, or elementary particles, such as electrons. Particle physics and nuclear physics study these particles and how they interact.
- field
- Particle physics, nuclear physics
- known_for
- Being smaller than atoms; classified as composite or elementary; subject to wave–particle duality and the uncertainty principle
Lore & Background
Subatomic particles are divided into composite particles, like protons and neutrons, which are made of other particles, and elementary particles, like electrons, which are not. The Standard Model lists elementary particles including six flavors of quarks, six types of leptons, twelve gauge bosons, and the Higgs boson. Most force-carrying particles such as photons and gluons are bosons, while particles with rest mass that cannot overlap are fermions; the W and Z bosons are exceptions with large rest masses.
Reader's Guide
Subatomic particles are fundamental to understanding the structure of matter and the forces that govern interactions at the smallest scales. The concept of wave–particle duality reflects that quantum-scale particles behave both like particles and like waves. The uncertainty principle states that some properties, such as simultaneous position and momentum, cannot be measured exactly. Interactions are understood in quantum field theory as creation and annihilation of quanta of fundamental interactions. Even among particle physicists, the exact definition of a particle varies, including definitions such as a collapsed wave function, an excitation of a quantum field, an irreducible representation of the Poincaré group, or an observed thing. The study of subatomic particles has led to the Standard Model, which successfully describes known particles and forces, though extensions predict undiscovered particles like the graviton.
Did You Know?
- Composite particles such as protons and neutrons are composed of other particles, while elementary particles like electrons are not.
- Most force-carrying particles like photons and gluons are bosons and do not have rest mass, but the W and Z bosons have relatively large rest masses.
- All observable subatomic particles have electric charge that is an integer multiple of the elementary charge, though quarks have non-integer charges that cannot be isolated due to color confinement.
- The Higgs boson, discovered in 2012, is the only elementary particle with spin zero.
Frequently Asked Questions
Who is Subatomic particle?
A subatomic particle is any particle whose size is smaller than that of an atom, ranging from composite types like protons and neutrons to elementary types like electrons. It sits at the heart of both particle physics and nuclear physics as the primary object of study.
What are Subatomic particle's powers/role?
Subatomic particles are governed by wave–particle duality and the uncertainty principle, so they can exhibit both wave-like and particle-like behavior while resisting perfectly simultaneous measurement of position and momentum. They interact through the fundamental forces laid out in the Standard Model.
How does Subatomic particle's story end?
There is no narrative ending, because subatomic particles are the building blocks of all ordinary matter and the universe as we observe it. Research in particle and nuclear physics is ongoing, continually refining our picture of how these particles behave and interact.
Why is Subatomic particle important?
Every atom, every nucleus, and every piece of everyday matter is constructed from subatomic particles, so understanding them is essential to explaining the physical world. They are the central subject of the two closely linked disciplines of particle physics and nuclear physics.
What is Subatomic particle's classification?
The Standard Model sorts subatomic particles into two broad categories: composite particles, which are made of quarks (such as protons and neutrons), and elementary particles, which have no known smaller constituents (such as electrons). This composite-versus-elementary split is one of the field's core organizing principles.
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