A quantum particle is a fundamental particle or a system of particles that exhibits quantum behavior according to the principles of quantum mechanics. Quantum mechanics is the branch of physics that describes the behavior of particles at the microscopic scale, where classical physics fails to provide an accurate description.
In quantum mechanics, particles are described by wave functions, which represent the probabilities of various properties (such as position, momentum, and energy) that can be measured. Quantum particles can exhibit wave-particle duality, meaning they can behave both as waves and as particles depending on the experimental setup and observation.
Quantum particles can exhibit phenomena such as superposition, where they can exist in multiple states simultaneously, and entanglement, where the properties of two or more particles become interconnected in a non-classical way. These phenomena are distinct features of quantum mechanics and set quantum particles apart from classical particles described by classical physics.
On the other hand, a micro-sized particle refers to a particle that is of small size on a macroscopic scale. The term "micro-sized" is not strictly defined and can vary depending on the context. Typically, it refers to particles that are smaller than the objects visible to the naked eye.
In the realm of particle physics, micro-sized particles can include atoms, molecules, and subatomic particles such as electrons, protons, and neutrons. These particles have sizes on the scale of nanometers (billionths of a meter) or smaller.
It's worth noting that quantum particles, such as electrons and photons, are typically considered to be micro-sized particles due to their extremely small size. However, there can be larger particles, such as certain molecules or aggregates of atoms, that may also exhibit quantum behavior.
The definitions of quantum particles and micro-sized particles emphasize different aspects: quantum particles focus on the behavior and properties dictated by quantum mechanics, while micro-sized particles primarily refer to particles of small size in relation to macroscopic objects.