Does Mass Have Volume? Photons Too?

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    Mass Volume
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Discussion Overview

The discussion revolves around the concepts of mass and volume, particularly questioning whether mass has volume and if photons, which are massless, can be said to have volume. The scope includes theoretical considerations of particle physics and quantum mechanics.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants propose that mass does not inherently have volume, suggesting that it is matter that possesses volume due to the structure of atoms and electron orbitals.
  • Others argue that photons do not have mass in the classical sense and therefore do not have volume, as they can occupy the same space as other photons without restriction.
  • A participant questions the notion that particles like W bosons and electrons have no volume, suggesting that at the quantum level, the concept of volume is not straightforward.
  • There is a discussion about the Planck volume and whether it could contain a large number of electrons, with some participants indicating that quantum mechanics complicates the classical understanding of volume.
  • One participant highlights that the probability of finding two electrons in the same state at the same time is zero, which raises questions about how to define the "volume" of an electron.
  • Another point raised involves wavefunctions and the uncertainty of an electron's exact position, questioning whether it occupies the entire region described by its wavefunction.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between mass, volume, and the nature of particles at the quantum level. No consensus is reached regarding whether mass has volume or how to conceptualize the volume of massless particles like photons.

Contextual Notes

The discussion highlights limitations in understanding particle volume at the quantum level, including the dependence on definitions and the complexities introduced by quantum mechanics.

dailydc
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Hi
Question is
Mass have volume ?

Another question is
Photons have mass "m=E/(c^2)" or "m = h*f/c^2" so
Photons have volume ?
 
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There is no physical size to a particle the way you think of it in your daily life. MATTER, not mass, has volume because electron orbitals in atoms have a finite radius from the nucleus and the repulsion of electrons vs electrons keeps other atoms at a distance, even when bound into molecules.

Light does not have mass in the sense of stationary rest mass, but it does have momentum. Usually momentum is a product of mass x velocity, but photons have no mass. Also, photons are Bosons, and as such they can occupy the same spot as other photons. In effect, they have no real volume like you would imagine it.
 
Drakkith said:
There is no physical size to a particle the way you think of it in your daily life. MATTER, not mass, has volume because electron orbitals in atoms have a finite radius from the nucleus and the repulsion of electrons vs electrons keeps other atoms at a distance, even when bound into molecules.

Light does not have mass in the sense of stationary rest mass, but it does have momentum. Usually momentum is a product of mass x velocity, but photons have no mass. Also, photons are Bosons, and as such they can occupy the same spot as other photons. In effect, they have no real volume like you would imagine it.

You say , W bosons and Charm quarks and electrons have no volume and do not Occupy space ?! :confused:

if we have plank volume ( 1.616252×10^−35 m ) ^ 3 , is it possible in the volume there are one million electron ?:confused:
 
Last edited:
dailydc said:
You say , W bosons and Charm quarks and electrons have no volume and do not Occupy space ?! :confused:

if we have plank volume ( 1.616252×10^−35 m ) ^ 3 , is it possible in the volume there are one million electron ?:confused:

No, I am saying the concept of "volume" is not the same at the quantum level. Classically a particle can have a volume, but when you get into quantum mechanics it gets more complicated. For example, the probability of finding two electrons at the exact same spot at the exact same time in the exact same state is 0. You could say that the "volume" of the electron could be found by measuring the electric field it emits, but you would be ignoring other issues. Conversely, a photon or other particle that does not obey the Pauli Exclusion Principle can easily occupy the same state as any number of other bosons. Meaning that it can occupy the same spot in space at the same time with any number of other bosons. This seems weird to most people, as our everyday experiences tell us differently. After all, when I stack cups in my cabinets they don't merge into one cup!

Then you would need to get into wavefunctions. An electron has a wavefunction that determines its position and momentum. But where exactly is the electron? We don't know! Does it occupy the entire region that the wavefunction describes, or does it roam around the area? See what I'm getting at?
 

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