In a matter-antimatter reaction, is all the material converted into energy? If not, what is the efficiency of the reaction?
Asked by: Heather Patterson
Yes, the reaction between matter and its corresponding anti-matter particles is 100% efficient,
converting all of the mass into energy. If you want to find the amount of energy produced
in any such reaction, just multiply the total mass (particles plus their anti-particles) in
kilograms by the speed of light squared (9 x 1016) and you will get the result in joules.
Because this reaction is 100% efficient, cosmologists believe that were it not for an
asymmetry that favors matter over antimatter, the Big Bang may have annihilated ALL matter
and produced a Universe filled with only energy.
Answered by: Paul Walorski, B.A. Physics, Part-time Physics Instructor
When it comes to Anti-matter, the annihilation effect converts the particle or particles that are
opposite the anti-particle. An example is the electron and positron. They annihilate each other
completely and the resultant energy is high end gamma ray radiation. If, on the other hand, there
is a hydrogen ion and a positron, the end result is a proton (maybe a neutron, depending on the
isotope) and gamma radiation. With anti-MATTER it depends on the particles used. Interesting
enough, If you reverse the process, by starting with the high end gamma ray radiation, you can
create electron/positron pairs. This is much much harder to do. To figure out the output (or
input) energy, use Einstein's energy equation: E=mc2.
Answered by: R Smiley
'The strength and weakness of physicists is that we believe in what we can measure. And if we can't measure it, then we say it probably doesn't exist. And that closes us off to an enormous amount of phenomena that we may not be able to measure because they only happened once. For example, the Big Bang. ... That's one reason why they scoffed at higher dimensions for so many years. Now we realize that there's no alternative... '