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  • Our universe, the galaxies, the solar system, our home planet earth

  • - land, sea, air, life

  • - where did they all come from?

  • Look up into space from our planet

  • and what you see is a vast cosmos - teaming with billions of stars and galaxies.

  • Turn back the clock over 13 billion years and our universe was a very different place,

  • back then it was small that it could fit inside the palm of your hand.

  • Form this infant universe everything would be created

  • - stars, galaxies and the building blocks of life itself.

  • the calcium in our bones, the iron in our blood

  • the atoms for the air we breathe - the water we drink

  • the raw materials for our cities and machines

  • Naked Science takes a journey through space and time

  • to discover how the universe was born

  • and how it created everything in our world

  • - and how eventually it will die.

  • Everything we see around us is made of matter - atoms and molecules.

  • Take this car - it's a 1956 Ford Fairlaine Convertible.

  • It's constructed from many different materials like steel, rubber and glass¡­

  • Go deeper and these materials are made up from combinations of elements like iron, silicon, chromium and carbon

  • Each and every atom that makes up this car were created by our growing universe.

  • Physicist Laurence Krauss studies how the atoms we see on our planet have come to be here

  • We really are part stardust and part big bang dust.

  • Most of the atoms in our body are from the cores of stars

  • but some of them have been around from the earliest moments of the big bang.

  • So we really are truly cosmic individuals

  • Each and every atom was created over billions of years as our universe evolved.

  • So when we look at this car, of course, all the atoms in this car came from stellar explosions,

  • from supernova processes and from stellar evolution,

  • but they were created at different times during the evolution of the Universe

  • To understand how the universe made all the raw material we see here on Earth,

  • we need to take an incredible journey

  • and travel back through space and time to the moment our universe was born.

  • In the beginning there was nothing.

  • No space, no time

  • And then there was light.

  • Suddenly a tiny speck of light appears - it was infinitely hot.

  • Inside this tiny fireball was all of space

  • This was literally the beginning of time.

  • The cosmic clock was ticking - time could flow and space expand.

  • At the earliest moments of the big bang, if you take it back to T=zero,

  • everything in our universe, everything we can see, all the matter and all the energy in all of the galaxies

  • was once contained in a region smaller than the size of a single atom today,

  • The idea that our universe was once tiny originated from the brilliant work of American astronomer Edwin Hubble.

  • Back in the 1920's most astronomers believed that everything visible in the night sky were stars

  • and they were part of our galaxy - the Milky Way

  • But Hubble wasn't convinced.

  • He studied a swirling cloud of light called the Andromeda Nebula and showed that it was a star city

  • another galaxy far outside of our own galaxy

  • He showed that these 'other' galaxies were speeding away from ours

  • and the further away they were, the faster they seemed to be moving

  • The universe was expanding

  • and if the universe was expanding, then at some point in the past it must have been smaller

  • - much smaller

  • and that it must have had a beginning.

  • The idea of the 'Big Bang' was born.

  • Theoretical physicist David Spergel is a Big Bang expert

  • The Big Bang theory is not really a theory of how the Universe began;

  • it's really a theory of how the Universe evolved

  • No-one knows exactly what happened during the Big Bang

  • but scientists do know that a fraction of a second after the universe was born

  • this tiny super-hot fireball was already starting to expand

  • We don't know how the Universe began,

  • so we start our story when the Universe was a billionth of a billionth of a billionth of a billionth of a minute old

  • Pretty young, the Universe was the size of a marble

  • Less than a trillion trillionth of a second after the Big Bang

  • the marble sized universe was very unstable and underwent an enormous growth spurt.

  • During this period of incredibly rapid expansion,

  • Space itself was expanding faster than the speed of light.

  • In the same way that this hot glass ball inflates, so did the baby universe

  • expanding in all directions at once and as it expanded it cooled.

  • A trillion trillionth of a second after the Big Bang the Universe was small enough to fit inside the palm of your hand.

  • A tiny fraction of a second later it was the size of Mars

  • Another fraction of a second and the baby universe had grown to 80 times the size of the earth.

  • A trillionth of a second after the Big Bang and our newborn universe was still expanding

  • But it didn't contain matter - it was pure energy

  • Einstein's famous equation E=mc2 showed that mass and energy are interchangeable

  • It gave us the knowledge to build weapons of mass destruction.

  • It also revealed how the universe created the first matter.

  • When a nuclear bomb explodes

  • a tiny amount of matter is annihilated and converted into energy.

  • In the baby universe the exact opposite happened.

  • It converted pure energy into particles of matter.

  • But there was a problem.

  • The universe created both matter and its arch rival anti-matter

  • - and when these two met they obliterated each other.

  • The infant universe was a war zone - a battle to the death between matter and antimatter

  • If they mutually annihilated each other the universe would remain full of energy with no galaxies, stars, planets or life

  • Fortunately for us there was an imbalance.

  • For every 100 million anti-particles formed, there were 100 million and 1 particles of matter

  • But there was that one extra particle of matter left over in each volume,

  • and that was enough to account for everything we see in the universe today,

  • This tiny imbalance led to all matter we see in the universe

  • - galaxies, stars, planets, - even convertibles and ourselves.

  • Astrophysicist Carlos Frenk from Durham University in England explains.

  • We are a little bit of debris left over from the annihilation of matter and antimatter;

  • we're the leftovers of that process.

  • If the Universe had not developed this slight asymmetry between matter and antimatter

  • the Universe would have been completely boring, there would be no structure, there would be no galaxies, there would be no planets,

  • Quite what this newborn Universe was like has challenged cosmologists since the Big Bang was first put forward.

  • Now in one of the biggest laboratories on Earth

  • they are able to recreate the conditions that almost certainly existed an instant after the Big Bang.

  • It's called the Relativistic Heavy Ion Collider - RHIC for short

  • and it's located at the Brookhaven National Laboratory on Long Island.

  • It's like a time machine - taking us back to 10 millionths of a second after the Big Bang

  • Here scientists like Todd Satogata accelerate subatomic particles close to the speed of light and then smash them into each other.

  • The particles race around this 2.5 mile long circular tunnel in opposite directions 78,000 times a second¡­

  • and then collide inside this giant detector - bigger than a 3 story house¡­

  • When they smash into each other they generate incredible heat - just like the real infant universe

  • We believe the early universe was extremely hot billions of times hotter than the centre of the sun

  • and what you're doing smashing these nuclei together is melting matter, creating matter hot enough to give us a glimpse of what the very early universe was like

  • When the particles collide they break open and throw out a shower of even smaller particles

  • It's a bit like discovering what cars are made of by watching them smash into each other

  • You can race two race-cars together and smash them into each other head-on,

  • and when you do that multiple times you start to see different patterns coming out,

  • a tyre comes out here, a radiator comes out there,

  • and before long you can start to conclude that a race-car is made up of these certain pieces.

  • What the scientists at Brookhaven have discovered is that within these superheated collisions a completely new form of matter appears.

  • And this matter contradicts the previous theories on the nature of the early universe.

  • Because it's not a gas - it's a liquid.

  • It was super hot - 100,000,000 times hotter than the surface of the sun

  • There was so much energy inside the young universe that the particles vibrated so fast that it had no stickiness

  • there was no friction and it flowed perfectly.

  • This liquid is perfect, it has no viscosity, in some sense it would be the perfect motor oil except it's a trillion degrees hot.

  • Inside the collider this amazing liquid Universe exists for only a tiny fraction of a second.

  • The Brookhaven scientists have succeeded in recreating conditions that existed over 13 billion years ago

  • Despite the universe being a perfect liquid - it was in turmoil.

  • It was full of subatomic particles smashing into each other releasing more and more energy

  • There was so much energy that unless the particles slowed down they would never bond and create atoms

  • - the building blocks of matter

  • - and the universe would never create the galaxies and stars or even us.

  • The universe is now one millionth of a second old

  • and has expanded from smaller than the size of an atom to 8 times the size of the solar system

  • After the incredible turmoil of the first millionth of a second the Universe was now relatively calm

  • Over the next three minutes the expanding cosmos cooled sufficiently for protons and neutrons to bind together

  • and form the first atomic nuclei: hydrogen and helium.

  • These were not yet proper atoms

  • They were missing a vital ingredient - the electron

  • In the hot baby universe there were plenty of electrons around,

  • but there was still so much heat and energy the electrons were moving too fast to form bonds

  • And it would stay that way for over three hundred thousand years.

  • 380,000 years after the Big Bang the universe had expanded to the size of the Milky Way.

  • It had cooled from billions of degrees Fahrenheit to a few thousand

  • As it cooled, the electrons slowed down.

  • The universe was now ready to make its first true elements.

  • One of the scientists who discovered this critical moment in the story of the universe was Arno Penzias.

  • 1963, 30-year-old Penzias and his 27-year-old colleague Robert Wilson began work on a new antenna in New Jersey.

  • Initially they were only studying cosmic radio waves

  • - but they would stumble on one of the greatest discoveries of all time.

  • As they started to test their equipment, they detected an unexpected background noise

  • It was an additional signal and it appeared to be coming from the sky,

  • we eliminated very carefully the ground, even the solar system,

  • because we did this winter to summer, seasonal variation,

  • man-made sources of equipment, all these things were eliminated.

  • In desperation, the two scientists began to wonder whether the strange signal might have another, more earthly, origin

  • They found there were pigeons roosting in the antenna, and it was covered with droppings

  • They wondered if the pigeons were the source of the strange signal.

  • There was only one solution: the droppings and the pigeons would have to go

  • When we finally got around to removing the pigeon droppings, we also had to remove the pigeons

  • and that was a difficult problem because they turned out to want to come back and so we mailed them off to another site

  • But even with the troublesome pigeons gone, the mysterious signal would not disappear.

  • so we were left with the inescapable conclusion that this radiation was coming from the sky.

  • I could not account for it

  • The strange signal detected by Penzias and Wilson would turn out to be one of the most important scientific discoveries of all time

  • But the explanation for their mystery background noise starts not with sound - but with the birth of light

  • We usually take light for granted.

  • But in the early universe 13 billion years ago, we would see nothing at all.

  • Light was trapped. The universe was foggy.

  • But as the universe continued to expand and cool the electrons slowed down

  • Protons then grabbed these calmer electrons to form complete atoms of first hydrogen and then helium

  • The universe was suddenly much less crowded with electrons

  • The fog lifted and light was no longer trapped.

  • It hurtled out across the universe - creating a blinding burst of light.

  • Had we been there we would have suddenly seen this opaque Universe become transparent,

  • suddenly the fog would lift and we would see a flash of light coming from everywhere around us.

  • It must have been a spectacular moment.

  • Over time, this burst of light dimmed and cooled and became microwave radiation.

  • It was this faint 13 billion year old microwave signal that Penzias and Wilson picked up on their antenna.

  • What they heard was the quiet echo of the moment the universe formed the first atoms

  • It's really the light from the origin of the Universe

  • If you have an old FM receiver, ¡­ if you tune between channels,

  • turn the knob and it doesn't capture it and pop to the station,

  • you get to a part where there's not, you hear a fffffff¡­. that's what we call noise.

  • If you have a good radio set, one half of one percent of that fffff¡­ is actually the sound of the Big Bang.

  • And we can also see the moment when the first elements were created

  • If our television is not tuned to a station, a tiny fraction of the noise is radiation from 13 billion years ago

  • But this radiation is not the only reminder of the birth of the Universe - even the water we drink is a memento

  • And it's kind of amazing to think that every time we take a drink of a glass of water,

  • we're drinking in atoms that have been around since the Big Bang - the hydrogen atom.

  • Over the next millions of years the young universe continued to expand, cool and get dark again

  • So far the Universe had only made hydrogen and helium atoms

  • but the world we live in is made from more than a hundred different kinds of elements

  • Without them the universe would remain a very boring place made up of only gas

  • a place where complex matter - like planets, cars and people could never develop.

  • The universe needed to get hydrogen and helium atoms to fuse.

  • And to do that it needed to make stars

  • The universe was now 200 million years old and billions of light years across.

  • Its temperature had dropped so far that it was colder than liquid nitrogen - minus 367 degrees Fahrenheit

  • It was also dark.

  • It would have remained a very gloomy place full of gas

  • but without galaxies, stars or planets if it hadn't been for one thing:

  • The baby Universe wasn't born perfect.

  • Carlos Frenk has created an amazing 3-D simulation of how the early universe evolved

  • It shows that when the Universe emerged from the Big Bang it was uneven.

  • Little cracks appeared which were very, very, very tiny, very, very small,

  • and it was this rash in the face of the baby Universe that later developed into the patterns that we see in the galaxies today

  • Without these cracks, the universe would have been a very dull place.

  • The first clues as to how these cracks developed into galaxies and stars

  • came when other scientists started to examine the Big Bang radiation first discovered by Penzias and Wilson

  • So Penzias and Wilson saw was this radiation was, as far as they can tell uniform,

  • What cosmologists then did for the next 25 years was work very hard to try to find tiny variations

  • And find them they did using WMAP

  • a space probe designed to detect and analyze in detail variations in the back ground Microwave radiation

  • Launched in 2001 the $150 million probe was fitted with some of the most sensitive instruments ever carried into space.

  • Our eyes detect only visible starlight

  • But WMAP can 'tune' into the invisible microwave radiation.

  • Once in orbit round the sun it picked up the faint radiation that has been rippling around the universe since the dawn of time.

  • So when we look at the cosmic background radiation

  • we're looking at this radiation that's been streaming towards us since half a million years after the Big Bang.

  • Initially the 'microwave universe' looked very dull and seemed to be the same everywhere

  • But when WMAP turned up the contrast: the results were spectacular.

  • The baby universe wasn't smooth and boring at all - it was full of fluctuations

  • These tiny fluctuations tell us what the variations in density, how much stuff there is, and how it varies from place to place

  • these denser regions are going to collapse to form clusters of galaxies and super-clusters and galaxies themselves

  • These low density regions, these will grow and become the empty regions between galaxies,

  • so this picture, really is our connection between the Universe when it was a baby half a million years old,