What is the Big Bang? (AQA GCSE Religious Studies A (8062))

Some scientists and religious people disagree about how the universe came into existence

Scientists believe that the Big Bang theory explains how the universe began

Some religious people believe that their scriptures explain exactly how the universe started and that God was the creator

Scientists believe that evolutionary theories can explain how living things have changed over millions of years to produce the complex life we see today

Some religious people believe that God created all living creatures. They believe that humans are all direct descendants of the first humans, Adam and Eve

Non-religious people look to science for answers about how the universe began. They believe that the universe started by chance

The Big Bang is the most significant of the Cosmological theories for how the universe began

It states that the universe began 8 billion years ago and involved a rapid expansion of matter and energy

• The matter of the universe was compressed into a tiny space

• Then there was a huge explosion which expanded the matter

• As the matter slowed down, gravity pulled it together to form stars and planets

• On planet Earth, the atmosphere developed, plants formed, and life evolved from the primordial soup

• The first were simple single-cellular beings and from these, all other life developed, including humans

• Scientists believe that the universe is still expanding and that the phenomenon of Red shift proves this

• Scientists also believe that Cosmic Microwave Background Radiation provides evidence of the heat caused by the Big Bang

Scientists believe that the Red Shift is evidence of the Big Bang and the expansion of the universe

In 1929 Edwin Hubble discovered that the universe is expanding. We now know that most other galaxies are moving away from us

Astronomers can observe light from distant galaxies. When they do this they see it is different to the light from the Sun

The dark lines from distant galaxies show an increase in wavelength

The lines have moved or shifted towards the red end of the spectrum

This led to the name - the Red Shift

Light absorption moves towards the red end of the spectrum as wavelengths get longer which suggests an increase in distance

According to the Big Bang theory, the early universe was very hot and full of radiation

As the universe expanded and cooled down, there would be a release of radiation

This is exactly what we see now as the Cosmic Microwave Background radiation (CMB)

CMB is a faint glow of light that fills the It is the oldest light we can see and so is the farthest back both in time and space that we can look

This light set out on its journey more than 14 billion years ago, before the Earth or even our galaxy existed

The light represents the residual heat of the beginning of the universe. It is the afterglow of the Big Bang

Many scientists believe this provides more evidence that the Big Bang brought the universe into existence