HISTORY OF THE UNIVERSE
1. WHAT WAS THE UNIVERSE LIKE AT THE BEGINNING?
Ans: The early universe was very small, but it contained all the matter and energy in the universe today. It was a dense and chaotic soup of tiny particles and forces, and instead of the four forces scientists know today, there was just one super force. But this original universe lasted only a split second. After just three trillion of a trillionth of a trillionth of a second, the super force split up into separate forces.
2. WHAT WAS THERE BEFORE THE UNIVERSE?
Ans: No one knows. Some people think there was an unimaginable ocean beyond space and time of potential universes continually bursting into life, or failing Ours succeeded.
3. WHAT WAS THE BIG BANG?
Ans: In the beginning, all the universe was squeezed into an unimaginably small, hot, dense ball. The Big Bang was when this suddenly began to swell explosively, allowing first energy and matter, then atoms, gas clouds and galaxies
to form. The universe has been swelling ever since.
4. CAN WE SEE THE BIG BANG?
Ans: Astronomers can see the galaxies hurtling away in all directions. They can also see the afterglow low level microwave radiation coming at us from all over the sky, called the background radiation.
5. HOW DO WE KNOW WHAT IT WAS LIKE?
Ans: We know partly by mathematical calculations, and partly by experiments in huge machines called colliders and
particle accelerators. These recreate conditions in the early universe by using magnets to accelerate particles to astonishing speeds in a tunnel, and then crash them together.
6. WHAT IS INFLATION?
Ans: Inflation was when dramatic expansion and cooling took place after the first second or so in the life of the universe, when spaces welled up and cooled enormously.
7. HOW DO WE KNOW THE UNIVERSE IS GETTING BIGGER?
Ans: We can tell the universe is getting bigger because every galaxy is speeding away from us. Yet the galaxies themselves are not moving-the space in between them is stretching.
8. HOW DID THE FIRST GALAXIES AND STARS FORM?
Ans: They formed from lumps of clouds of hydrogen and helium, either as clumps broke up into smaller, more concentrated clumps, or as concentrations within the clumps drew together.
9. HOW OLD IS THE UNIVERSE?
Ans: We know that the universe is getting bigger at a certain rate by observing how fast distant galaxies are moving. By working out how long it took everything to expand to where it is now, we can wind the clock back to the time when
the universe was very, very small indeed. This suggests that the universe is between 10 and 20 billion years old. However, studies of globular clusters suggest some stars in our galaxy may be older than this.
History of the Universe
♦ Content of the Universe click here