How does Mass measure Energy?A system's mass is nothing else that the energy contained inside that system (divided by the constant c2).
A system's mass is nothing else that the energy contained inside that system (divided by the constant c2)
It is incorrect to say that:It is correct Lee, no kidding. The trick to it is to look at electron-positron annihilation (http://en.wikipedia.org/wiki/Electron%E2%80%93positron_annihilation), and to understand that the electron is "a system". Einstein said a body loses mass through radiation. When annihilation occurs, the electron loses mass through radiation. It loses all of its mass. Then the system called the electron, the "matter", no longer exists.QuoteA system's mass is nothing else that the energy contained inside that system (divided by the constant c2)
for they are clearly different; if they were not, we would all be living in radiation and not matter.
This is very interesting and much appreciated. Now, Will you or anyone else work out a formula of E=mc2.Sorry, what do you mean with "work out"? The meaning of that formula?
If you can not do that, will you, or anyone else, please give me a formula for Mass? There are two unknowns in the equation: E-mc2. I can see no way to get a number with the two unknowns. Thanks for comments. Joe L. OganIt depends. If you know mass from something else, you can compute the energy with that formula (provided that system's momentum is zero); if you know the energy from something else, you can compute the mass.
1. "Matter" is not "mass". The first means "particles with non zero rest mass", the second means E/c2.
It is incorrect to say that:QuoteA system's mass is nothing else that the energy contained inside that system (divided by the constant c2)
for they are clearly different; if they were not, we would all be living in radiation and not matter. However, matter and energy may be inter-converted and so may be considered equivalent in the same sense that a tank full of heating oil is equivalent to a warm home in winter. You only need to try living in a tank full of heating oil to spot the difference between them though.
Are you telling me that the equation E = mc2 is not workable?Sorry but I'm not native english speaking, so I don't understand what exact meaning to associate to "workable" in this context, so I'll try to explain better what I've already written.
I have found out that the constant for Mass is the Kilogram. I assume that matter must be converted to Kilograms in order to work the equation E = mc2. What would prevent that? Thanks for comments. Joe L. OganCan you explain better what you mean?
It is incorrect to say that:It is correct Lee, no kidding. The trick to it is to look at electron-positron annihilation (http://en.wikipedia.org/wiki/Electron%E2%80%93positron_annihilation), and to understand that the electron is "a system". Einstein said a body loses mass through radiation. When annihilation occurs, the electron loses mass through radiation. It loses all of its mass. Then the system called the electron, the "matter", no longer exists.QuoteA system's mass is nothing else that the energy contained inside that system (divided by the constant c2)
for they are clearly different; if they were not, we would all be living in radiation and not matter.
Check out The nature of the electron by Qiu-Hong Hu which appeared in Physics Essays, Vol. 17, No. 4, 2004. You can find it at http://arxiv.org/abs/physics/0512265. Most people haven't heard of this yet, it's a shame Nature turned it down. But it's good peer-reviewed science. Electrons really do have angular momentum and spin, and they really are made out of radiation using pair production (http://en.wikipedia.org/wiki/Pair_production). In a nutshell, when you employ pair production to split a photon and make it go round and round instead of moving laterally at c, we don't call it a photon any more. We call it an electron.
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2F8%2F84%2FPairproduction.png&hash=aa57bee443cd37e92335a953ab616b40)
(Or a positron, if it's the opposite chirality).
Joe: see http://en.wikipedia.org/wiki/Mass_in_special_relativity#The_mass_of_composite_systems for a formula. If the momentum p is zero because you're talking about a particle rather than a system of moving particles, the expression reduces to m=E/c2.
1. "Matter" is not "mass". The first means "particles with non zero rest mass", the second means E/c2.
It is incorrect to say that:QuoteA system's mass is nothing else that the energy contained inside that system (divided by the constant c2)
for they are clearly different; if they were not, we would all be living in radiation and not matter. However, matter and energy may be inter-converted and so may be considered equivalent in the same sense that a tank full of heating oil is equivalent to a warm home in winter. You only need to try living in a tank full of heating oil to spot the difference between them though.
2. As I explained a lot of times, the system have to be still, or you cannot use E = mc2. A photon cannot be still, so you can never use E = mc2 so you cannot say that for a photon the mass is E/c2. Infact it's massless...
3. Suppose you havea box with two holes and a laser light pulse enter one hole and exit the other. During the little interval of time in which the light pulse can be localized (or part of it) inside the box, the box acquires a mass m = E/c2 if E is the light pulse's energy.
Infact it's massless...
You say that energy consists of both energy ("hot body") and mass ("weighs more"), and that relativity never seems to be explained properly. I know E = mc² regarding the creation/annihilation/conversion of mass and energy. So you seem to be saying that the real input/increase of energy into a hot(ter) body is:Sorry Dave, I've been tied up. No, I didn't mean the above. The delta energy is due to the heat alone. If you look closely at say a container of gas, when you heat it the individual molecules move faster, temperature being a measure if their average motion. Whilst no one molecule has a greater mass, the overall mass of the container of gas is increased.ΔEnergy = ΔEnergyheat + ΔmΔEnergyheatc²
So, all of my explanations and you still haven't understood... [:(]1. "Matter" is not "mass". The first means "particles with non zero rest mass", the second means E/c2.
It is incorrect to say that:QuoteA system's mass is nothing else that the energy contained inside that system (divided by the constant c2)
for they are clearly different; if they were not, we would all be living in radiation and not matter. However, matter and energy may be inter-converted and so may be considered equivalent in the same sense that a tank full of heating oil is equivalent to a warm home in winter. You only need to try living in a tank full of heating oil to spot the difference between them though.
2. As I explained a lot of times, the system have to be still, or you cannot use E = mc2. A photon cannot be still, so you can never use E = mc2 so you cannot say that for a photon the mass is E/c2. Infact it's massless...
3. Suppose you havea box with two holes and a laser light pulse enter one hole and exit the other. During the little interval of time in which the light pulse can be localized (or part of it) inside the box, the box acquires a mass m = E/c2 if E is the light pulse's energy.
Sigh... more nonsense.
The reason that E=mc2 cannot be applied to photons is because [the photon], as you eventually point out...QuoteInfact it's massless...
...so of course if you tried to apply E=mc2 to a photon you'd end up with a big fat 0. It's got nothing to do with whether the photon is 'still' or not.
I'll also just remind you that there is no absolute frame of reference, so the notion that anything is 'still' is purely relative.Another meaningless phrase...
Do you honestly really think that an electron is just a photon that's orbiting an atomic nucleus?Not at all. I think you've misread something there. A photon "going round and round" is an electron or a positron depending on the chirality. Do read http://arxiv.org/abs/physics/0512265. It might be unfamiliar to you, but it's a bona-fide peer-reviewed paper.
Electrons are not only made as a consequence of combining two photons but also as a result of free neutron decay.Yes, Beta-minus decay. It's very informative.
Also, you can't employ pair production to 'split' a photon; that's rather like putting the cart before the horse. What happens is that a high-energy photon interacts with other matter (usually an atomic nucleus) and the electron-positron pair are produced as a result.And if there's not enough energy they annihilate, and the result is (usually) two 511keV photons. The original photon is definitely split.
The electron in the pair is very unlikely to end up being 'adopted' by the atom that produced it, and end up going round and round instead of laterally.As above. The photon going round and round is the electron. Another paper offering what is essentially the same model is "Is the electron a photon with a toroidal topology?" Williamson and van der Mark, Annales de la Fondation Louis de Broglie, Volume 22, no.2, 133 (1997). You can access it and a draft new paper at http://www.cybsoc.org/cybcon2008prog.htm#jw.
Incidentally, what do you think happens to the positron that's also produced? You fail to mention its fate.Typically the electron and the positron fly off with some considerable velocity. The positron is likely to meet an electron and annihilate.
Sigh... more nonsense. The reason that E=mc2 cannot be applied to photons is because [the photon], as you eventually point out, [is massless], so of course if you tried to apply E=mc2 to a photon you'd end up with a big fat 0. It's got nothing to do with whether the photon is 'still' or not.I'm afraid this really is how it works Lee. It lies at the heart of relativity, is the very basis of E=mc2, and dates back to 1905. It certainly isn't nonsense. If a body emits radiation, it loses mass. That body can be a mirrored box containing photons.