Our Universe What it is like, how it started, how it evolved to its current state, and how it will end

Early universe……. Hard to study……… Math breaks Divide by zero errors Brains break

FUTURE EVERYTHING!

Super stretch Everywhere Everywhere Stretch! Space and time expansion Still happening

STARTS EXPANDING….. EVERYWHERE Stretch! ENERGY INCREASING, BECOMING LIKE A BOMB…….

BOOM! Not an explosion

Hot stretch! Space expands

Time starts Tick tick tick…… Before “bang”? Bad question. It is like asking what is North of North pole.

The Universe Looked More Like This a white hot plasma

The Big Bang Not really an ‘explosion’ Universe expanded rapidly as a whole Matter was created in the form of tiny particles (protons, neutrons, electrons) Too hot for normal ‘stuff’ to form (eg atoms, molecules) Four forces/rules separate

E=mc2 Plasma begins cooling Particles precipitate out of matter Energy =mass Just particles, hot stretchy space and time No stars, galaxies, life or Biebers

COSMIC ‘SOUP’

COSMIC ‘SOUP’ PROTON NEUTRON ELECTRON

300,000 Years Later….. Universe much cooler, atoms start to form….. Hydrogen, Helium, normal ‘stuff’

Universe is now a GAS

Universe is now a GAS HELIUM HYDROGEN

GRAVITY!

Gravitational Collapse We started with a uniform gas Small regions became more dense The denser regions had larger gravity and started to pull other particles towards them The gaseous Universe began to look ‘clumpy’

Formation of Structure! The Universe began very hot & dense following the Big Bang. As it expanded and cooled, large clouds of gas could be compressed by gravity, forming stars and galaxies..

Gravitational Collapse Regions with more particles (higher density) become gas clouds Gas clouds become stars and galaxies Galaxies congregate together in filaments, groups and clusters

But we are inside one of these galaxies, so all we see are the nearby stars. We can see other galaxies if we use a telescope

Cosmic Microwave Background Radiation! Shows that the universe is nearly the same temperature in every direction. Indicates a massive explosion-like event occurred in the universe about 13.7 Billion years ago! http://www.astro.cornell.edu/~rbean/images/cmb_popup.jpg

The BIG BANG! Evidence: The universe is expanding. The amount of gas in the universe matches with what should have been created by a big bang. We see dim microwave radiation coming from every direction… an afterglow!

The Gemini Telescope

Working Timeline since BB

Future? The Universe is still expanding All galaxies are moving apart The ‘explosion’ of the big bang is still happening! It may contine expanding forever Or is may stop expanding, and fall inwards in a big CRUNCH!

What have we learned? The Universe started with a BIG BANG Gradually the particles were drawn together under GRAVITY to form STARS and GALAXIES Many stars have planets around them The fate of the Universe is uncertain…

THE END