The Energy in our Universe

Dr. Darrel SmithDepartment of Physics

Sources of Energy in the Universe

1.   Matter    a.  Gravity    b.  Fusion

2. Photons --  CMB  2.7 deg.

3. Neutrinos  --  1.7 deg.

4.   Dark Matter

5.   Dark Energy

Our SunHow much power is generated by the sun?

a) 200 megawatts 2 x 108 wattsb) 5,000 terawatts 5 x 1015 wattsc) 2,500 exawatts 2.5 x 1021 wattsd) 380,000,000 exawatts 3.8 x 1026 watts

The power is called the Luminosity (watts)

How does it make that energy?

Fusion of hydrogen p p p n e+ ne

T + D He4 + n

Surface Temperaturevs.

Core Temperature

What does it cost to make all this sunshine?

In other words, what does this do to the mass of the sun?

a) Mass is converted to energy

b) Power

c) 1% of the solar mass 100 billion years to burn off

Energy from type 1a Supernovae

Type 1a Supernovaea)Releases a uniform amount of

energy 1-2 x 1044 joules

b)Luminosity ~ 5 billion times greater than the sun

c) ~10 billion stars in our Milky Way galaxy

Formation of a supernovae

Remnants of Supernovae

Crab Nebula (1054 AD)

Power output = 5 x 1031 W = 130,000 Lo

A pulsar in the core providesthe energy.

Pulsar is a highly magnetizedrotating neutron star.

Rotational K.E. is decreasing.

Supernovae observed

1054 AD Observed by the Chinese

Observed by Anasazisin Chaco Canyon

6500 light years away

1987A Supernova in the LargeMagellanic Cloud.

Supernovae Summary

1.  Energy comes from where?2.  Where does the energy go?3.  Source of heavy elements4.  Indicator of Dark Energy

Particle Astrophysics

Big Bang CosmologyHow do we know what the early universe was like? The LHC at CERN

Big Bang Cosmology

From t=0 through todayHow do we know this? Particle Astrophysics

Particle AstrophysicsThe Tevatron at Fermilab

The Large Hadron Collider (LHC)

Geneva, Switzerland

Standard ModelThe physicists equivalent to the periodic table.

Unifies QCD with EW interactions into a single structure.

It does not include gravity.

It is a quantum field theory that is consistent with quantum mechanics and special relativity.

Standard Model

q = +2/3 e

q = -1/3 e

q = 0 e

q = -1 e

Particles have masses

Mp = 0.938 Gev/c2

Big Bang Cosmology

What is the Higgs Particle?

So, how do particle acquire mass?

Through their interaction with the Higgs field.

W+

W-

Zo

How is the Higgs formed?

• The fusion of one quark from each proton.

• Coming together at high energy.

A simulated event in the Atlas detector

How is the Higgs formed?

•The fusion of one gluon from each proton.•Coming together at high energy.

A simulated event in the Atlas detector

Why such a big machine?

We need high energies to make massive particles.

E = mc2

Why such small distances?

We need to put that energy in a small volume to make a high energy density.

l = h/p

Mass vs. Size

Mass is not proptional to size.

Masses of the W and Z particles

MW = 82 GeV/c2

Mz = 90 GeV/c2

Mproton = 0.928 GeV/c2

Galactic Rotation Curves

Velocity = constant (??)

Bulge + Disk + Dark Halo

Where’s the “missing mass” ?

Could it be neutrinos? Could it be black holes?

Dark EnergyDifferent from “dark matter”

It causes the universe to expand (i.e., to accelerate outward.

How is this observed?

http://imagine.gsfc.nasa.gov/docs/science/mysteries_l1/dark_energy.html

Dark EnergyChanges in the rate of expansion

The more shallow the curve, the faster the rate of expansion.

Dark EnergyMost of the energy in the universe today is “dark energy.”

Next, comes “dark matter.”

Only 4% of the universe is made of “regular matter.”Neutrons, Protons, electrons, photons, & neutrinos.

Exotic PropulsionHow can we travel through our galaxy?

Matter-Antimatter propulsion

Nuclear-Thermal Propulsion

Faster-than-light propulsion (??)