Smallest known subatomic particles
Pro Research Analysisby 
Searched over 200M research papers
Elementary Subatomic Particles: Quarks, Leptons, and Gauge Bosons
The smallest known subatomic particles are called elementary particles. According to the Standard Model of particle physics, these include quarks, leptons (such as electrons and neutrinos), and gauge bosons (like photons and gluons). These particles are considered fundamental because, as far as current experiments show, they are not made up of anything smaller—they have no known internal structure and cannot be divided further 17.
Quarks and Leptons: The Building Blocks of Matter
Quarks are the smallest known constituents of protons and neutrons, which themselves make up the nuclei of atoms. There are six types of quarks, but the up and down quarks are the most common in ordinary matter. Leptons include the electron, which orbits the nucleus of an atom, and the neutrino, which is extremely light and rarely interacts with other matter. Both quarks and leptons are considered elementary, meaning they are not composed of smaller particles 17.
Gauge Bosons: Force-Carrying Particles
Gauge bosons are another category of elementary particles. They are responsible for carrying the fundamental forces of nature. For example, photons carry the electromagnetic force, gluons carry the strong nuclear force, and the W and Z bosons carry the weak nuclear force. These particles are also considered fundamental and are not known to have any substructure .
Hypothetical and Proposed Smaller Particles
Some researchers have proposed the existence of even smaller particles, such as the "tamaid" and "bach" particles, which are suggested to have masses smaller than the electron. However, these particles have not been confirmed by mainstream experiments and are not part of the Standard Model 34. Other speculative ideas include "Micra" particles and "whits," but these remain theoretical and lack experimental evidence 56.
Theoretical Considerations and Ongoing Research
While the Standard Model currently treats quarks, leptons, and gauge bosons as the smallest known particles, there are still open questions in physics. For example, it is not yet fully understood whether quarks and electrons are truly indivisible, or if there might be even smaller constituents yet to be discovered. The search for answers continues, with new models and theories being proposed to address these mysteries .
Conclusion
In summary, the smallest known subatomic particles are the elementary particles described by the Standard Model: quarks, leptons, and gauge bosons. These particles are considered fundamental because they have no known substructure. While there are speculative ideas about even smaller particles, none have been confirmed by current scientific evidence. The quest to understand the true building blocks of matter continues to drive research in particle physics 17.
Sources and full results
Most relevant research papers on this topic