dark matter group ac 8

DARK MATTER

Presentation by: Ernesto Jiménez, Irene

Mengibar and Irene Wbanet

Introduction

• Everything we can see is made of atoms.

• Ordinary matter is just a 5% of the

universe.

• Evidence for dark matter (95%):

1.Cosmic Microwave Background.

2.The need of more matter than the visible

one to explain some gravitational effects.

Definition of dark matter

• Dark matter is a 27% of the universe.

• It is not reactant to light.

• It is important because of its gravitational

effects in the universe’s structure.

1st type: Cosmological constant

• It is spread all around the universe,

homogeneously.

• It is the simplest for of dark energy

because it is constant in space and time.

• It is the type which causes the expansion

of the universe.

2nd type: Scalar fields

• Is dynamic, so constant over space but

changes over time.

• Can change over space also but these

ones are very similar to cosmological

constant.

String Theory

1. Macroscopic level: Matter2. Molecular level3. Atomic level: Protons, neutrons, and electrons4. Subatomic level: Electron5. Subatomic level: Quarks6. String level

String Theory

• One string is the base of matter

• Each oscillation makes a sub-particle

• It makes up their properties

• It also explains particle interaction

Sub-particles

Supersymmetry

• Relates fermions with bosons

• Haven’t been observed yet.

• Suggest a

common origin

Superpartner examples:

Leptons Leptons

Squarks Quarks

Photon Photino

Neutralino ?

What is dark matter?

• Dark matter is not in the form of stars and

planets that we can see.

• It is not in the form of dark clouds of

normal matter, otherwise we could detect

the baryonic clouds which forms this

matter

• Dark matter is not antimatter, because we

can’t see the gamma rays

Composition

There are two different possibilities:

•The WIMPS (Weakly interacting Massive

Particles)

•The MACHOs (Massive Compact Halo

Objects)

WIMPs

• They are subatomic particles which are

not made up of ordinary matter.

• They include neutrinos, axions and

neutralinos

MACHOs

• They are objects ranging in size from

small stars to super massive black holes.

• They are made up of ordinary matter (like

protons, neutrons and electrons)

• They may be black holes, neutron stars or

brown dwarfs.

Pandora’s Cluster

• A complex collision of at least four galaxy

clusters

• Strange effects that have never been seen

together before

• It has apparently been produced because of this

smash-up.

• Dubbed "Pandora's Cluster" because of all of

the different structures found.

• Officially known as Abell 2744

• Located about 3.5 billion light years from Earth.

PANDORA’S CLUSTER

Pandora’s Visions

XRAY VISION OPTICAL VISION LMAP VISION

NOW PREPARE YOURSELF

FOR…

A TEST

Only one answer is valid…

• What does not react to electromagnetic

waves in any significant form?

A: Dark energy

B: Dark matter

C: Cosmic Microwave Background.

Test

• What does not react to electromagnetic

waves in any significant form?

A: Dark energy

B: Dark matter

C: Cosmic Microwave Background.

Test

Test

• What is the value of the energy density

of the vacuum of space?

A: Dark energy

B: Black holes

C: Cosmological constant

Test

• What is the value of the energy density

of the vacuum of space?

A: Dark energy

B: Black holes

C: Cosmological constant

• How would the supersymmetrical

partner of an up quark be called?

A: Down quark

B: Antiup quark

C: Up squark

D: Up quark hasn’t got any

supersymmetrical partner

Test

• How would the supersymmetrical

partner of an up quark be called?

A: Down quark

B: Antiup quark

C: Up squark

D: Up quark hasn’t got any

supersymmetrical partner

Test

• How many sub-atomic particles are

there in the standard model?

A: 15

B: 18

C: 17

Test

• How many sub-atomic particles are

there in the standard model?

A: 15

B: 18

C: 17

Test

• Can you name the three particles

included in WIMPs?

A: Protons, neutrons and neutralinos

B: Neutrinos, axions and electrons

C: Neutrinos, axions and neutralinos

D: Neutrinos, neutrons and neutralinos

Test

• Can you name the three particles

included in WIMPs?

A: Protons, neutrons and neutralinos

B: Neutrinos, axions and electrons

C: Neutrinos, axions and neutralinos

D: Neutrinos, neutrons and neutralinos

Test

• What are MACHOs?

A: They are subatomic particles which are not made up of ordinary matter.

B: They are very small objects made up of neutrinos, axions and neutralinos

C: They are subatomic particles not made from ordinary matter

D: They are objects ranging in size from small to massive black holes

Test

• What are MACHOs?

A: They are subatomic particles which are not made up of ordinary matter.

B: They are very small objects made up of neutrinos, axions and neutralinos

C: They are subatomic particles not made from ordinary matter

D: They are objects ranging in size from small to massive black holes

Test

• WIMPs are…

A: Weakly Interacting Massive Particles

B: Weakly Interesting Massive Particles

C: White Infrared Massive Pieces

D: Widely Interacting Massive Particles

Test

• WIMPs are…

A: Weakly Interacting Massive Particles

B: Weakly Interesting Massive Particles

C: White Infrared Massive Pieces

D: Widely Interacting Massive Particles

Test

HOPE YOU LIKED IT!!

Be careful with black holes….