I've heard that it is incredibly difficult to detect a graviton, but I don't quite understand why. With all of the knowledge I have at the present time it seems like it should be possible to create a graviton in a particle accelerator. This is how I figure: a graviton is massless, so the collision shouldn't need to have too high of an energy. Since gravity acts upon anything with energy, a graviton field should couple with all of the other fields, so it seems like gravitons could be created in collisions. A graviton created this way would probably not show up on traditional detectors, but the two units of spin associated with the particle would be missing from the observed decay products. What is wrong with this picture?It may come from a naive understanding of scattering, as I am no physicist (yet.)
p.s. I have the same misunderstanding regarding axions. They are predicted to be light particles, so why aren't they created in collisions?