1. DARK MATTER
By: Maeve de Bordons, Paula
Elorza and Paula Gurucharri.

2. •
•
•
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-Definition
-Interesting Facts
-Other theories
-News on Dark matter-How close are
we to finding dark matter?

3. Definition:
• Dark matter is a type of matter hypothesized
in astronomy and cosmology to account for a
large part of the mass that appears to be
missing from the universe.
• Dark matter cannot be seen directly with
telescopes; evidently it neither emits nor
absorbs light or other electromagnetic
radiation at any significant level.

4. Interesting facts:
• When the universe was still young clumps of dark
matter have likely attracted gas, which then
coalesced into stars that eventually assembled the
today's galaxies.
• Black holes absorb dark matter, and over the
billions of years since galaxies were first formed,
this absorption of dark matter in black holes has
very likely altered the population of galaxies from
what we can observe today.
• Despite the recent improvement in astronomy, there
is still a great deal of unknown about origin,
properties and distribution of dark matter in the
universe.

5. • Dark matter is an misterious energy that
contains most of the Universe's mass. This
concept was used for the first time by Fritz
Zwicky in 1933.
• The density of the dark matter in a galaxy
has its maximum in the center and it
gradually decreases as it gets to the
outermost part, but the same process
significantly increases the total size of the
galaxy.
• Determining the nature of dark matter is one
one of the most important challenges in
cosmology that attracts many scientists.

6. • Dark matter makes up roughly 85 percent of
the matter in the universe.
• Methods for detecting dark matter include
direct and indirect detection methods, which
cannot be directly observed since it does not
emit radiation.
• Direct methods: simultaneous light and heat
detection, simultaneous heat and ionization
detection, and simultaneous light and
ionization detection, such as research into
distinctive signals (the most famous being
the search for an annual modulation in the
dark matter signal caused by the orbiting of
the Earth). Indirect detection methods: do not
directly seek the dark matter particles but
researchers try to identify other particles,
(neutrinos, photons, etc.), produced when
the Universe's dark matter particles are
destroyed.

7. OTHER THEORIES
• Some Researchers in Chile believe that dark matter
isn´t existent based on studies they have done, they
believe the fact that galaxies ( like the milky way)
move is because of another form of gravitation.
• Empty Space Filled With "Virtual" Particles
theory by Hajdukovic

8. • The quantum vacuum is the name physicists give to what
we see as empty space.
• Antimatter particles are mirror opposites of normal matter
particles. For example, an antiproton is a negatively
charged version of the positively charged proton, one of
the basic constituents of the atom.
• When matter and antimatter collide, they clash in a flash of
energy. The virtual particles spontaneously created in the
quantum vacuum appear and then disappear so quickly
that they can't be directly observed.
• In yhis new mathematical model they investigate what
would happen if virtual matter and virtual antimatter were
not only electrical opposites but also gravitational
opposites—an idea some physicists previously proposed.
• "Mainstream physics assumes that there is only one
gravitational charge, while I have assumed that there are
two gravitational charges," Hajdukovic said.
• That would mean matter and antimatter are gravitationally
repulsive, so that an object made of antimatter would "fall
up" in the gravitational field of Earth, which is composed
of normal matter.

9. How close are we to finding
dark matter?
• Dark matter makes up about a quarter
of the cosmos, but we still don't know
what it is. As part of a two-part series
called Light & Dark on BBC Four,
physicist Jim Al-Khalili pondered how
close we are to understanding the
mysterious "dark stuff".

10. • Dark matter is one of the greatest mysteries in
the cosmos , an invisible substance thought to
make up five-sixths of all matter in the universe.
The scientific consensus right now is that dark
matter is composed of a new type of particle,
one that interacts very weakly at best with all the
known forces of the universe, except gravity. As
such, dark matter is invisible and nearly
completely intangible, mostly only detectable via
the gravitational pull it exerts.

11. • Given all the progress made in modern physics
over the past century, you may be forgiven for
thinking that physicists are approaching a
complete understanding of what makes up
everything in our Universe.
• For example, all the publicity surrounding the
discovery of the Higgs boson last year seemed
to be suggesting that this was one of the final
pieces of the jigsaw :that all the fundamental
building blocks of reality were now known.
• So it might come as something of a shock to
many people to hear that we still don't know
what 95% of the Universe is made of.

12. • The problem with dark matter is that, whatever it
is made of, it seems to interact very weakly with
normal matter. This makes it very hard to catch like trying to catch a shadow
• There are three different ways we can try to find
out what dark matter is made of. We can look
out into space and see the results of collisions of
dark matter particles by trying to detect the
normal matter particles created in the debris of
these collisions; or we can try to catch dark
matter particles directly as they stream through
the Earth; or we make them ourselves in particle
accelerators like the Large Hadron Collider at
Cern.