Are W Bosons Truly Massive Particles or Just an Effect of Energy Equivalence?

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SUMMARY

The discussion centers on the nature of W bosons, particularly their existence as massive particles versus virtual particles in weak decays. W bosons are approximately 100 times more massive than protons, but in the context of neutron decay, they are typically virtual particles rather than real ones. The conversation highlights that most weak decays do not generate real W bosons due to insufficient energy, leading to the creation of virtual W bosons instead. The top quark, however, can produce real W bosons during its decay, resulting in a faster decay process.

PREREQUISITES
  • Understanding of particle physics concepts, particularly weak interactions.
  • Familiarity with the energy equivalence equation (E=mc²).
  • Knowledge of particle mass measurements and relativistic kinematics.
  • Basic comprehension of virtual versus real particles in quantum mechanics.
NEXT STEPS
  • Research the role of virtual particles in quantum field theory.
  • Study the properties and decay processes of the top quark.
  • Examine the implications of the Higgs mechanism on particle mass.
  • Learn about the Standard Model of particle physics and its components.
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Physicists, students of particle physics, and anyone interested in the nuances of particle behavior in weak decays and the implications of mass in quantum mechanics.

OmCheeto
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About 40 years ago, someone told me that free neutrons decay with a half life of around 14 minutes.
About 10 years ago, I discovered that W bosons were involved, and that they are about 100 times as massive as a proton.

Do W bosons really exist as "massive" particles for their very brief lifespan?
Or is their mass merely derived from the energy equivalence equation, and no one really knows?

Thanks!
 
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I don't think your two statements are in conflict. We determine the masses of many things - most unstable particles - through relativistic kinematics ("energy equivalence equation" is just a special case), But yes, the W has a rest mass.
 
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OmCheeto said:
About 10 years ago, I discovered that W bosons were involved, and that they are about 100 times as massive as a proton.
The "W bosons" in neutron decays are not real particles. They do not need to have the mass of real W bosons.
 
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Also, it's good to know that most weak decays don't have enough energy to create a real (on shell) and massive W bosons, so only virtual (off shell) W bosons are created in the process.
But the top quark is massive enough to create a real W boson in the decay process, which makes its decay a lot faster than other particles.
 
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mfb said:
The "W bosons" in neutron decays are not real particles. They do not need to have the mass of real W bosons.

Garlic said:
Also, it's good to know that most weak decays don't have enough energy to create a real (on shell) and massive W bosons, so only virtual (off shell) W bosons are created in the process.
But the top quark is massive enough to create a real W boson in the decay process, which makes its decay a lot faster than other particles.

I think this is what I was really asking; "Is the W- Boson involved in free neutron decay real, or virtual?"
And your's was the answer I was hoping for.
It's sometimes difficult for laymen to determine from pop-sci articles when particles are real, and when they're virtual.

Double thanks!
 
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OmCheeto said:
Double thanks!

Double no problem
 
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