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Vanishing Particles?

  1. Mar 26, 2004 #1
    To be honest this is more of a question that a theory but it'll be interesting to see the responses.

    If mass is equivilent to energy at an atomic level and everything is made up of atoms then is it fair to assume that the mass of anything is equivilent to its energy? That is the energy within it due to the motion of its atoms. If you can imagine a situation where a particle was at rest surely, no matter what, it would have zero energy, and therefor zero mass? now for something like a neutron, it may be possible to isolate a neutron and hold it still, in this situation it would still have mass, however this is due to the motion of the quarks within which make up the neutron. if we can stop the quarks then it may have no energy and therefor cease to exist. An electron cannot be split into smaller things so if u can stop an electron then it should possess no energy internally and therefor cease to exist also. The question is, if it were possible (which is isn't) to stop a particle (and all its components) from moving would it be reduced to zero mass and cease to exist?

    Not a hugely interesting subject but comments would be appreciated
     
  2. jcsd
  3. Mar 26, 2004 #2
    Electrons loose energy in the form of photons, so they can be made into smaller things, electrons with less energy.
    Conservation of Energy dictates that the energy cannot simply disappear.

    The interaction of the components of a particle comprises a system. If you were to stop the components interacting, then the system/particle would cease to exist, but the components/energy would not.
     
  4. Mar 26, 2004 #3
    What seems unclear to me is that if energy and mass are effectively the same thing the removing the energy from something (in the form of photons, for example) results in its mass decreasing. how is this possible unless mass IS energy. and in this case the photons which carry the energy out of the system must have mass.

    I can grasp the idea that energy and mass are equivilent but i cant see how this is true. on a large scale if you have something which is very hot (lots of energy) and you cool it down it must lose mass? surely this mass cant simply become energy? why would it prefer to turn into a massless photon and shoot off with some energy. why not just fly off as a particle with mass ? or why fly off at all ?
     
  5. Mar 26, 2004 #4
    Is that to say that the smallest component of everything is that which can carry away energy (a photon?) I support the idea that everything is made up of photons, with some things more willing to give them up than others, but i was under the impression that this idea was totally wrong
     
  6. Mar 26, 2004 #5
    I think the humble little photon has more to do with particles than it's being credited with.
    When electrons jump shelves, what's involved - photons.
    When dealing with electromagnetic fields, what's involved - photons.
    Heat transfer is infrared radiation - photons.

    There may be theories, but I've not seen anything concrete.
     
  7. Mar 27, 2004 #6
    You could perhaps create some energy through neutrone fussion.
    Never heard of anyone trying. Maybe it's a nuclear waste of time!
     
  8. Mar 27, 2004 #7

    Doc Al

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    Staff: Mentor

    Just because a particle has zero kinetic energy does not mean it has zero mass.
     
  9. Mar 27, 2004 #8
    I like this idea cause it speaks in favour of my convictions that the charge (being also proportional with energy E=VQ; V=electric potential; Q=charge) and the mass of every single particle are variable thus there is no point of talking about elementary particles.
     
  10. Mar 27, 2004 #9
    I like the idea of everything being made of photons. It kind of fits with the idea that photons do have mass (however small it may be) because if something radiates energy then it is radiating photons, and therefor losing mass at a very low rate. an electron for example will reduce in energy by losing photons which also constitutes a loss in mass, until eventually it will have no energy (and no mass) because it has disipated into billions of tiny photons. Just an idea, but seems logical to me.
     
  11. Mar 27, 2004 #10
    If photons are the basis of everything that we know, then there is no need for an individual photon to have mass. Being the most fundemental building block, their mass would have to be then based on something even more fundemental.
    If a particle comprises a number of photons, then the seperation of the photons would provide a measurement of distance, and subsequently provide a value for the mass of the particle.
    If the particle is a system, its properties do not have to reflect those of its components, hence the particle can have mass even it the photons that go into making don't. In much the same way that photons do not have charge, but other particles do.
    The addition of more energy would further enhance the particle and effect the seperation of the existing photons resulting in an potential increase in mass.
     
  12. Mar 27, 2004 #11
    It was my understanding (whether correct or not) that the mass of a photon (if it had one) was dependant on the observed frequency of that photon. Because frequency determines momentum and their speed is fixed, so it must be their mass that changes? If this is the case then a particular particle which only emits certain frequencies of light can be thought of as doing so because it only contains photons of certain masses.
     
  13. Mar 27, 2004 #12
    Photons are the one particle that Relativity has a problem with, unless they possess no mass at all. There have been attempts to determine the mass of a photon, and some upper limits have been placed on it, but mostly it is regarded as massless.
    The frequency of the photon is directly related to its energy - See Planck.

    When a particle emits a photon it is not the mass that it is emitting, but energy. The mass of the particle may have decreased due to the loss of the energy.

    The limitation of the frequencies emitted by certain particles, let's assume they're atoms, is caused by an electron at a specific energy level loosing energy. The amount of energy that it looses is governed by the shell that the electron is located on and the shell it is jumping to. I'm fairly sure that an electron will only jump to the next shelf and not make a random jump to just any shelf.
     
  14. Mar 27, 2004 #13
    I understand the view that photons are massless because otherwise it disagrees with relativity but to me it seems more logical if they do have mass. An electron looses energy when it moves energy levels but why should it only jump to certain energies? (i dont much like the idea of energy levels). If an electron loses energy in the form of a photon then the mass of the electron will also decease (by E=mc^2) so what is wrong with the assumption that the loss in mass is equal to the mass of the photon (if this is assumed then the mass is found to be very small, i think atleast 100,000 times smaller than the electrons mass). the mass of an electron is virtually zero, so this photon which is many orders of magnitude smaller can be assumed to have no mass, but this assumption cannot be correct because at the high speeds which photons travel this small mass presents a relatively large momentum.
    I'm not trying to use quantum physics (electron energy levels for example) to explain my idea. I'm presenting a new idea which disagrees with quantum physics to a certain extent. The loss of energy by an electron is observed to occur in definate values but what is wrong with my explanation over the explanation currently in use?
     
  15. Mar 27, 2004 #14
    Isn't kinetic energy relative anyway? If you're passing by a "motionless" electron, you could say that the electron is passing by you and therefore it has speed and kinetic energy.
     
  16. Mar 27, 2004 #15
    I believe it is but if an electron loses a photon the speed of the photon relative to the electron is equal to the speed of light, and vice versa. so the kinetic energy of each relative to the other is equal to mc^2. This means that if the electron loses 1eV of energy (i have no idea how realistic that value is, just an easy number to use) then that 1eV is the energy of the photon which is given off. using E=mc^2 the mass lost by the electron can be found, and this loss in mass is equal to the mass of the photon (or atleast this is what i propose)
     
  17. Mar 27, 2004 #16
    When a photon is given off, its speed is not relative to that of the electron. It's speed is 186,000 miles per second regardless of whatever speed the electron is travelling at.
    So the velocity of the photon has nothing really do with the electron. It as natural velocity. The question should be - why ?

    The only reason why the velocity would be so rigid, is if it was governed by something.

    If the photon is pure energy and is transmitted through a medium at a set rate, then you can determine the possible mass of a photon using Planck's constant.
    Because the speed of light is the natural rate at which the energy is transmitted the photon can have mass, but is not effected by relativity.

    Essentially the photon is the only basic particle. The rules by which it is governed then determine the subsequent properties of all other particles.

    I hope that makes sense.
     
  18. Mar 27, 2004 #17
  19. Mar 27, 2004 #18
    Organic, thanks for the link.

    It would appear that particles from the major groups have been created using photons.

    This does beg the question : What else is there ?

    I suspect the answer is - nothing.
    Everything can be constructed from, and reduced down to photons.
     
  20. Mar 27, 2004 #19
    What about other force carrying particles (Gluons or Gravitons for example) could these be photons aswell ? because they are emitted by particles (which are made of photons) so surely they must also be photons, or perhaps many photons together. If this is the case then a Theory of Everything would simply be a theory of photons, how they interact and behave in different situations
     
  21. Mar 27, 2004 #20
    Maybe everything is that simple.
    Here's a link my Theory pages which basically says just that.
     
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