Not sure if that's true Sav. E=mc^2 might hold the answer to whether the photon has mass or not. And I'd hypothesize that it does have mass, based off of what I read on
this site, particularly the 2nd picture. At least it has mass, plus the potential to convert into more mass, or it's pure energy that can convert into mass and vice versa.
Although the way Einstein puts it, it's either energy or mass. What if, energy is just the "building blocks" for mass? Wouldn't the building blocks have their own infintessimal amount of mass? Maybe part of the problem is that we just don't have the instruments sensitive enough to measure mass at such a small level yet.
Might as well post the relavent points here...
Quote:
The deep connection Einstein discovered between energy and mass is expressed in the equation E=mc . Here E represents energy, m represents mass, and c is a very large number, the square of the speed of light. Full confirmation was slow in coming. In Paris in 1933, Irne and Frdric Joliot-Curie took a photograph showing the conversion of energy into mass. A quantum of light, invisible here, carries energy up from beneath. In the middle it changes into mass -- two freshly created particles which curve away from each other.
The first photograph showing the creation of a pair of particles, revealed by the fog spots they make in passing through the wet air of a "cloud chamber." The two particles, curving apart under the influence of a magnet, were created in the annihilation of a particle of light (coming invisibly from below).
This photograph not only shows the conversion of energy to mass, but confirms Einstein's idea that a light-particle will yield up its quantum of energy all at once in a single burst.
Image Archives Curie et Joliot-Curie, Paris.
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To listen to Albert Einstein explain his famous formula:
www.aip.org/history/einstein/sound/voice1.wav "It followed from the special theory of relativity that mass and energy are both but different manifestations of the same thing -- a somewhat unfamiliar conception for the average mind. Furthermore, the equation E is equal to m c-squared, in which energy is put equal to mass, multiplied by the square of the velocity of light, showed that very small amounts of mass may be converted into a very large amount of energy and vice versa. The mass and energy were in fact equivalent, according to the formula mentioned above. This was demonstrated by Cockcroft and Walton in 1932, experimentally."
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I'm guessing that atoms (matter) are just organized, or structured, pieces of energy. That site also references experiments to prove that E=mc^2 is true by converting mass into energy, by smashing atoms. The leftover mass after the collision was less than the original quantity, because the missing mass was converted into energy. The energy released was measured accurately enough to correspond to what E=mc^2 tells us what should have been released. Very interesting.
So what if the "missing mass" of the universe, or Dark Matter, is missing because of the Big Bang? The mass was converted into a ginormous (yes, ginormous
) amount of energy, expanded throughout the cosmos, and all the matter we see will continue to expand forever? Or is the total amount of matter expected was based on the theory that all the matter of the universe is expected to collapse, only to go into another big bang, and so on...?
Lastly, what is the unit of measurement for energy in E=mc^2? Is it quanta