Particles less massive than leptons?

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SUMMARY

This discussion centers on the search for particles less massive than leptons, specifically questioning the relationship between mass and size. Participants clarify that leptons, such as electrons and neutrinos, are elementary particles, and the least massive known particles are neutrinos. The conversation also touches on the theoretical existence of massless particles like gravitons and photons, emphasizing that massless particles cannot be directly compared to massive particles. Additionally, the concept of particle size is debated, particularly regarding the Planck length and the definition of point-like particles.

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  • Understanding of elementary particle physics
  • Familiarity with the Standard Model of particle physics
  • Knowledge of mass and size relationships in quantum mechanics
  • Basic concepts of Planck length and its significance
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  • Research the properties and implications of neutrinos in particle physics
  • Explore theories surrounding massless particles, including gravitons and photons
  • Study the concept of point-like particles and their definitions in quantum mechanics
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granpa
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People are always smashing particles together with more and more energy searching for and finding more and more massive particles.
Have there been any searches for particles less massive (and therefore larger) than leptons?
 
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At present the least massive (non-zero mass) known particles are neutrinos.

Your comment is a little puzzling - why would less massive particles be larger?
 
Leptons are elementary particles and I believe that article deals with confinement of many particle systems such as the electron clouds and atomic nuclei/Quark Confinement.
 
There are tons of people out there doing tons of experiments. Odds say some are looking for said particles. There are some theories about lighter mass particles which are being searched for (graviton, photon, etc.)
 
Gravitons and Photons are massless so you can't compare it to a particle like a Neutrino or any other massive particle for that reason. It's like saying what's less least massive known apple? A kiwi, it's unassosciative.
 
mathman said:
At present the least massive (non-zero mass) known particles are neutrinos.

Your comment is a little puzzling - why would less massive particles be larger?

<br /> \lambda= { \hbar \over m c}<br />
 
I thought all elementary particles are point like, and their size is the Plank Length or around there.
 
Constantin said:
I thought all elementary particles are point like, and their size is the Plank Length or around there.

That statement is contradictory. How can something be pointlike and at the same time be characterized by some length?
 
  • #10
Because a point in physics is not infinitely small.
Plank length is the shortest measurable length.
 
  • #11
Constantin said:
Because a point in physics is not infinitely small.
Plank length is the shortest measurable length.
Whilst the latter statement may be true, the former isn't. A point is a point. The notion of a "point" in physics is not distinct from topological notion of a point.
 
  • #12
Constantin said:
Because a point in physics is not infinitely small.

If a point is not infinitely small (zero dimensional), it's by definition not a point.
 

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