300 likes | 461 Views
The Energy in our Universe. Dr. Darrel Smith Department 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 Sun. How much power is generated by the sun?
E N D
The Energy in our Universe Dr. Darrel Smith Department 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 Sun • How much power is generated by the sun? • 200 megawatts 2 x 108 watts • 5,000 terawatts 5 x 1015 watts • 2,500 exawatts 2.5 x 1021 watts • 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 pppne+ne T + D He4 + n Surface Temperature vs. Core Temperature
What does it cost to make all this sunshine? • In other words, what does this do to the mass of the sun? • Mass is converted to energy • Power • 1% of the solar mass 100 billion years to burn off
Energy from type 1a Supernovae • Type 1a Supernovae • Releases a uniform amount of energy 1-2 x 1044 joules • Luminosity ~ 5 billion times greater than the sun • ~10 billion stars in our Milky Way galaxy
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 Anasazis in 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 elements • 4. Indicator of Dark Energy
Particle Astrophysics • Big Bang Cosmology • How do we know what the early universe was like? • The LHC at CERN
Big Bang Cosmology • From t=0 through today • How do we know this? Particle Astrophysics
Particle Astrophysics • The Tevatron at Fermilab
The Large Hadron Collider (LHC) Geneva, Switzerland
Standard Model • The 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
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 Energy • Different 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 Energy • Changes in the rate of expansion • The more shallow the curve, the faster the rate of expansion.
Dark Energy • Most 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 Propulsion • How can we travel through our galaxy? • Matter-Antimatter propulsion • Nuclear-Thermal Propulsion • Faster-than-light propulsion (??)