the big bang fact or fiction n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
The Big Bang: Fact or Fiction? PowerPoint Presentation
Download Presentation
The Big Bang: Fact or Fiction?

Loading in 2 Seconds...

play fullscreen
1 / 18

The Big Bang: Fact or Fiction? - PowerPoint PPT Presentation


  • 83 Views
  • Uploaded on

The Big Bang: Fact or Fiction?. The Big Bang. Fact or fiction?. Dr Cormac O’Raifeartaigh. The expanding universe (1929 ). many galaxies moving apart. rewind graph: universe converges infinite density, temp beginning of time: Big Bang?. The origin of the universe. Georges Lemaitre.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

The Big Bang: Fact or Fiction?


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
the big bang fact or fiction
The Big Bang: Fact or Fiction?

The Big Bang

Fact or fiction?

Dr Cormac O’Raifeartaigh

the expanding universe 1929
The expanding universe (1929)

many galaxies

moving apart

the origin of the universe
rewind graph: universe converges

infinite density, temp

beginning of time: Big Bang?

The origin of the universe

Georges Lemaitre

t~ 14 billion yr

Expanding and cooling ever since

newton
Newton

Newton’s gravity

  • planet orbits due to gravity
  • gravity caused by sun’s mass

What is pushing out?

modern theory of gravity
Modern theory of gravity

General theory of relativity

  • space + time = space-time
  • space-time not fixed
  • affected by mass

Einstein

gravity = curvature of space-time

r elativity and the expanding u
Relativity and the expanding U
  • dynamic U
  • expand or contract
  • depends on mass

Apply Einstein’s gravity to Universe

Alexander Friedmann

evidence ii composition of the elements
U = 75% H, 25% He

Observed

Evidence II:Composition of the elements

BB Prediction

Georges Gamow

Heavier elements: 0.1%

Formed in stars

evidence iii cosmic background radiation
BB prediction

radiation leftover from BB

low temperature

low frequency

Evidence III:Cosmic background radiation

Alpher, Gamow and Herman

cosmic microwave background 1965
radio interference

low frequency

temperature 3 K

Cosmic microwave background (1965)

Observed

Penzias and Wilson

Echo of Big Bang

modern measurements
Modern measurements
  • accurate CMB spectrum
  • homogeneous?
  • how do galaxies form?

COBE satellite (1992)

wmap satellite
WMAP satellite
  • highly homogeneous
  • flat universe
  • ev idence for inflation

WMAP satellite (2002)

inflation
Inflation
  • explains galaxy formation
  • explains flatness of U
  • solves horizon problem

Alan Guth

Hyper- expansion

immediately after BB

new surprises
New surprises
  • U speeding up

Supernova

  • U flat
  • Dark energy
outstanding puzzles
Outstanding puzzles
  • Nature of inflation?
  • Nature of dark energy ?
  • Singularity at time zero?

Further reading: ANTIMATTER

the big bang model
The Big Bang model

14 billion years ago, universe concentrated at a point

Primordial explosion of matter, energy, space and time

Universe expanding and cooling ever since

Misnomer: singularity problem

cosmological model
Cosmological model

Known matter: 4%

Dark matter: 23%

Dark energy: 73%

Flat universe

evidence for general relativity
Evidence for general relativity
  • bending of light by gravity
  • time stretching by gravity
  • black holes