From: Georgi Guninski <guninski@guninski.com>
   What is the importance of antimatter?
   >As is known, I don't understand physics.
   The front page of wikipedia links to new results in antimatter
   related to antihydrogen.
   [1]https://en.wikipedia.org/wiki/Antihydrogen
   >What is the importance of antimatter not counting nukes?
   I'm not aware of any significance of antimatter in regards to nukes.
   (neither bombs nor fission reactors; there are many potential fusion
   reactions; I don't recall if any produce a substantial number of
   antiparticles. )
   >Why antimatter is accepted by the standard model in physics, but
   anti-time and anti-space appear to be considered cranky topic?
   The anti-electron (aka positron) was predicted in 1931 by Paul Dirac.
   [2]https://en.wikipedia.org/wiki/Positron   It was actually discovered
   in 1932, presumably as a spiral in a cloud chamber.   (It would be
   circling similar to an electron, because it has the same mass, but in
   the opposite direction, since it has a positive electric charge, in the
   static magnetic field applied to the cloud chamber.)
    You ask why it is "accepted":  Generally, things that are found tend
   to be "accepted".   What's the alternative?
   For years, it was speculated that the Big Bang 'should' have produced
   equal amounts of ordinary matter and anti-matter, but despite this
   seemingly the vast majority of the known universe is ordinary matter.
   (evidence:  absence of gamma rays that would exist profusely if
   electrons and positrons were continuing to collide and annihilate in
   today's world.)
             Jim Bell

References

   1. https://en.wikipedia.org/wiki/Antihydrogen
   2. https://en.wikipedia.org/wiki/Positron