Sanny wrote:
> I heard in our Universe there is Matter & anti Matter.
Yes.
> Then there is Dark Matter.
Perhaps. Observations of it are only indirect, and it is conceivable
that it is some sort of artifact of our instruments and the theories
(GR) used to analyze the observations. Virtually all physicists consider
this unlikely, however.
> Are Dark Matter and Anti Matter seen by Scientist?
Antimatter is produced at every high-energy particle accelerator, and in
the atmosphere by cosmic rays. The Fermilab Tevatron produces
antiprotons in copious amounts, collects and accelerates them to ~1 TeV,
and collides them with protons.
Dark matter is observed only indirectly via its gravitational effects.
It has never been observed directly (i.e. as a signal in a detector, or
similar). There is a claim of observation of a handful of objects that
could be consistent with dark matter particles, but they are not
generally accepted as such.
> Whare are they made of do they have neutrons/ protons/ electrons?
Antimatter is made whenever elementary particles interact with
sufficient energy. Many/most of the cosmic rays entering the atmosphere
have much more energy than required; ditto for numerous particle
accelerators. Antimatter nuclei have antiprotons and antineutrons, and
antimatter atoms add antielectrons (positrons).
Nobody knows for dark matter (assuming it exists). Some theorize it is
primordial (i.e. came direct from the big bang), others guess it was
produced in a manner similar to nucleosynthesis in the first
nano-milli-femto-microsecond after the big bang, and others aren't sure.
> If not are they too made of Quarks?
Antimatter hadrons are made of quarks and antiquarks (just like matter);
antimatter leptons are not. Just like hadrons and leptons.
Remember that mesons consist of a quark and an antiquark,
so a pi- is just an anti-pi+ (etc.). Electrons and muons
are elementary, and contain no other particles, including
quarks.
Dark matter cannot be made of quarks, or it would interact strongly with
matter (which is not observed).
> Is Dark Matter and Anti-Matter simmilar?
No. They are VERY different, at least to current detectors and in
current theories.
> Will Dark Matter and Matter Collide give out energy?
As far as we know today, dark matter does not interact in any way except
gravitationally. This could change if, as, and when it is directly detected.
> Will Anti-Matter and Matter Collide will give out energy?
When a particle and its antiparticle collide sufficiently closely that
they annihilate, energy is invariably released. For hadron/antihadron,
other particles can also be released, but for lepton/antilepton only
gammas (high-energy photons) are released.
> Do Dark Matter has mass and gravity?
Yes.
> Do Anti-Matter has mass and gravity?
Yes.
Tom Roberts
