{{Short description|Domain of physical sizes which are smaller than atoms}} {{See also|Subatomic particle|Atomic spacing|Planck scale|Quantum mechanics}}{{Unreferenced|date=October 2025}} The '''subatomic scale''' is the domain of physical size that encompasses objects smaller than an atom. It is the scale at which the atomic constituents, such as the nucleus containing protons and neutrons, and the electrons in their orbitals, become apparent.
The subatomic scale includes the many thousands of times smaller '''subnuclear scale''', which is the scale of physical size at which constituents of the protons and neutrons—particularly quarks—become apparent.
Broadly this may be conveniently divided into: * '''Fundamental''' elementary particles as small as {{val|1|e=-19|ul=m}}, quanta that have not yet been further divided. *'''Nuclear''' or femtometer {{val|1|e=-15|ul=m}} scale related to subatomic particles == See also ==
* Astronomical scale the opposite end of the spectrum
Category:Subatomic particles
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