Is this a Violation of the Law of Conservation?

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Discussion Overview

The discussion revolves around the concept of mass conservation in the context of electrons radiating energy as electromagnetic radiation. Participants explore the implications of energy loss, mass, and the nature of potential energy within atomic systems.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants question why electrons do not lose mass when radiating energy, suggesting a misunderstanding of mass and energy relationships.
  • One participant notes that when an atom emits a photon, it loses mass in principle, although this effect is extremely small and not typically measured.
  • Another participant mentions that in synchrotron radiation, while kinetic energy decreases, the invariant mass remains unchanged.
  • There is a discussion about the relationship between energy and mass, with one participant suggesting that energy can be considered similar to mass, leading to questions about mass loss.
  • Some participants clarify that potential energy is a property of the entire system (the atom) rather than individual particles, though this distinction is debated.
  • One participant emphasizes the current understanding of mass as being based on its effects rather than its causes, highlighting ongoing research in particle physics.

Areas of Agreement / Disagreement

Participants express differing views on the nature of mass and energy, particularly regarding whether mass is lost during radiation. There is no consensus on the implications of energy loss for mass conservation.

Contextual Notes

The discussion includes unresolved distinctions between potential energy as a system property versus individual particle properties, and the complexities surrounding the understanding of mass in physics.

Who May Find This Useful

This discussion may be of interest to those exploring concepts of mass, energy, and atomic physics, particularly in the context of radiation and conservation laws.

Nano-Passion
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How come electrons don't lose mass as they radiate a field energy in the form of electromagnetic radiation?
 
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What situation are you thinking of?

When an atom drops to a lower electronic energy level and emits a photon, the atom as a whole (system of electron plus nucleus) loses mass, at least in principle. I don't think this decrease in mass has ever actually been measured because it's so small.

In something like synchrotron radiation, the electron loses kinetic energy. This causes a decrease in "relativistic mass", although what most physicists call "mass" (the invariant mass or "rest mass") stays the same.
 


Nano-Passion said:
How come electrons don't lose mass as they radiate a field energy in the form of electromagnetic radiation?

They lose kinetic and potential energy instead.
 


The_Duck said:
They lose kinetic and potential energy instead.

Interesting, now isn't energy similar to mass also; so that you can weigh energy in a sense. So wouldn't it henceforth lose mass?
 


This is true for a composite system like jtbell was discussing. If electrons in an atom loses potential energy, the atom should have a smaller mass.
 
Potential energy is a property of a system (the atom), not of the individual particles (electron and proton) that make up the system.
 
Nano-Passion said:
How come electrons don't lose mass as they radiate a field energy in the form of electromagnetic radiation?

As EM photons have no "rest mass" their "emission" from an electron does not change the mass of that electron.
 
jtbell said:
Potential energy is a property of a system (the atom), not of the individual particles (electron and proton) that make up the system.

I don't think that distinction is all that rigorous. I don't even think the distinction can be made which object "has" the energy...either the nucleon+electron individually or the atom as a whole...
 
To the OP:
In a large sense you are attempting an understanding of "mass"

That's totally fine, but be aware that all we currently know about mass is it's effects.
We DO NOT KNOW what causes it.

Hopefully, LHC experiments can assist in our understanding.
 
  • #10
pallidin said:
To the OP:
In a large sense you are attempting an understanding of "mass"

That's totally fine, but be aware that all we currently know about mass is it's effects.
We DO NOT KNOW what causes it.

Hopefully, LHC experiments can assist in our understanding.

I love the way you put that: that we know its effects but not what causes it.
 

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