# Mass transported at speed of light

nakurusil said:
After annihilation the container is "filled" with the energy of the resulting photons. I think I explained this to you about 3 times now.
Filled or Full ?

As the photons have no mass, they are considerably smaller than the original occupants of the container. Could more positrons/electrons be added to the contents of the box ?

The container isn't empty.
Is it still full ?

Filled or Full ?

As the photons have no mass, they are considerably smaller than the original occupants of the container. Could more positrons/electrons be added to the contents of the box ?
Your initial question was answered many posts ago, now you seem to generate a new set of questions just for the reason that you refused to accept the obvious answer to your initial question (what happened to the mass of the positron/electron pair).

I will answer your new question nevertheless, without doing calculations because you seem to ignore them:

1. The box was initially filled with matter.
2. After annihilation it is filled with the energy of the resulting photons.
3. Without doing the necessary calculations, it is not possible to add any more massive particles into the box because the process of adding even one more particle would require infinite energy. I will let you prove that to yourself, it is an interesting exercise. You will need to use math.

You'd be hard pressed to find a box strong enough not to explode in your face.

The answer has nothing to do with "As the photons have no mass, they are considerably smaller than the original occupants of the container. ". It is a nonsense to even attempt to talk about the

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nakurusil said:
Your initial question was answered many posts ago, now you seem to generate a new set of questions just for the reason that you refused to accept the obvious answer to your initial question (what happened to the mass of the positron/electron pair).
Your answers, including this one, all refer to the mass becoming energy. The mass was already energy before the annihilation.

nakurusil said:
it is not possible to add any more massive particles into the box
The box no longer contains any massive particles. The electrons and positrons, which have a radius of 2.8179 × 10−15m, no longer exist.
All that is contained in the box are photons which are dimensionless.

Now even I can do the math for that

n * volume of an electron/positron != n * 0​

Your answers, including this one, all refer to the mass becoming energy. The mass was already energy before the annihilation.

The box no longer contains any massive particles. The electrons and positrons, which have a radius of 2.8179 × 10−15m, no longer exist.
All that is contained in the box are photons which are dimensionless.

Now even I can do the math for that

n * volume of an electron/positron != n * 0​

Not the right math. Try again.

Mute
Homework Helper
Your answers, including this one, all refer to the mass becoming energy. The mass was already energy before the annihilation.
And the chemical energy in a battery is still energy when it has been converted into electrical energy and heat, but the forms of energy are not equivalent.

The box no longer contains any massive particles. The electrons and positrons, which have a radius of 2.8179 × 10−15m, no longer exist.
All that is contained in the box are photons which are dimensionless.

Now even I can do the math for that

n * volume of an electron/positron != n * 0​
You're using the "classical electron radius", though, which is just an estimate of the electron's radius based on classical physics alone. Quantum mechanically, the electron is a point particle of zero size, so

n*volume of an electron/positron = 0​

jtbell
Mentor
The electrons and positrons, which have a radius of 2.8179 × 10−15m,
Where did you find that number? All I've ever seen has been upper limits on the size of an electron or positron. These simply indicate the limitations of whatever experimental technique was being used. That is, "if the electron has finite size, it must be less than this amount, otherwise we would have detected it."

For example, http://arxiv.org/abs/hep-ph/0002172, which gives an upper limit from an experiment at LEP, of $2.8 \times 10^{-19}$ m.

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Mute said:
And the chemical energy in a battery is still energy when it has been converted into electrical energy and heat, but the forms of energy are not equivalent.
In line with that, the energy of the electron/positron is still energy when it is converted to that of a couple of photons, but the form has changed.

Bare in mind that orbiting electrons can absorb/emit photons when changing shelves to increase/decrease their energy levels, so the form of the energy must be fairly compatible.

Except here there is no chemical reaction. The other properties of each particle cancel each other out.

The form of the energy changes without the addition of any energy or other particulate property. One moment it has mass, the next it doesn't (please note all previous posts about invariant mass - let's not go there again).

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When dealing with electrons/positrons annihilation, the only way to calculate the transition to gamma rays is using invariant mass. The reason for this is because if you don't use invariant mass, then the equation doesn't balance. The reason it won't balance is because on one side of the equation you have relativistic mass and on the other side you do not. To say that the mass was converted to energy takes you away from using invariant mass and in to using relativistic mass which it appears to be quite widely agreed that you can't do. Relativistic Mass cannot be used to calculate the outcome of this process because photons have none and any reference to E=MC^2 is using the wrong math.

The reason that invariant mass must be used is because there is currently no method of manipulating Relativistic Mass into anything else. Sure, you can use E=MC^2 to determine the amount of energy your playing with, but that's as far as you can take it.
Whatever it is that is the root cause of, or at least has a part to play in Relativity is lost at the moment an electron/positron pair is annihilated. The requirement to add increasingly more energy to these particles to get them to travel at ever higher velocities no longer applies.
Whatever was preventing those particles from travelling at the speed of light was removed when the energy became photons, in fact travelling at the speed of light suddenly became mandetory.

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