- jonb,
Antimatter's basically matter with an opposite charge. The antiparticle will annihilate whatever particle it touches, converting both particles to energy.
The problem is, there's not much antimatter in the unvierse; the only naturally-occurring antimatter we ever encounter is matter bombarded with cosmic rays. And it takes a lot of energy to turn matter into antimatter.
Single antiparticles are still doable, but enough to do any significant damage isn't. To give you an idea, PET, or Positron Emission Tomography, scans bombard your body with positrons and track the gamma rays.
The problem is, there's not much antimatter in the unvierse; the only naturally-occurring antimatter we ever encounter is matter bombarded with cosmic rays. And it takes a lot of energy to turn matter into antimatter.
Single antiparticles are still doable, but enough to do any significant damage isn't. To give you an idea, PET, or Positron Emission Tomography, scans bombard your body with positrons and track the gamma rays.