THE BIG BANG – ORIGINS OF THE UNIVERSE

Aitor Ganuza & Alvaro del Castillo

1- Introduction. Along the history, there have been many different theories and thoughts. The aim of this presentation is to explain them.

2- Making questions about the universe is not something recent. It has been made since the human made his first footsteps. They answered them with myths, as you can see in the caves paintings.

3- Nut was the Egyptian sky goddess. She was depicted as a giant woman who was supporting the sky with her back. Her body was blue and covered by stars. Ancient documents describe how each evening, the Sun entered the mouth of Nut and passing through her body was born each morning out of her womb.

4- In the beginning was the void. It was at some ancient time in the Aztec creation story that the dual god created itself. This god was good and bad, chaos and order, male and female. Being male and female, it was able to have children. It had four, which came to represent the four directions of north, south, east and west.

5- But then, myths changed to religion. Christianity, for example, believed that god created the earth and universe in 7 days. But there are also other ideologies and religions. But science and religion didn't get on well in those days.

6- Religion was a stumbling block for science to develop. Scientists were afraid of the holy inquisition because they tortured and killed everyone who didn’t think the same as them.

7-However, nowadays the point of view of some Christian denominations has changed. In fact, some Conservative Protestant Christian denominations have also welcomed the Big Bang theory as supporting a historical interpretation of the doctrine of creation.

8- Introduction to the scientific point of view. It started in the ancient Greece, but nowadays for the last 65 years it has developed a lot due to the new technologies and the informatics.

9- The Big Bang and the Steady State theory are both models of how the universe began. The Steady State Theory is not well known and is disregarded by many people. Most observations made since 1950 have contradicted the steady state theory and supported the Big Bang theory.

10- The main differences between the two theories is that the big bang theory states that the universe started from a single point and the Steady State theory states that the universe had no start and it is always expanding.

11- George Lemaitre, a Belgian priest, was the first to suggest the bBig Bang theory in the 1920s. Then Edwin Hubble’s observations of galaxies moving away from Earth and many other findings all support the theory.

12- According to this theory, the universe started 13.8 billion years ago. Suddenly, there was a big explosion. Some people think that it must have been such a noisy boom, but it didn’t make a sound as there was no air. It's hard to imagine that before, it was nothing.

13- Scientists say that before the big bang that “nothing” was an state of singularity. There was an infinite number of dimensions and no space or time.

14- At the first millisecond, the universe was incredibly small, dense and hot. This homogenous area of the universe spanned a region of less than 1 milimetre. Today, that same stretch of space spans billions of light years. During this phase, big bang theorists believe, matter and energy were inseparable. The four primary forces of the universe were also a united force.

15- After the first three hundred thousand years atoms started to form, one billion years later first galaxies appeared, and 13.8 billion years have passed until now.

16- Light created during the Big Bang, which is detectable today as cosmic microwave background radiation. It has not mass and it has the fastest speed of the universe.

17- Protons have positive charge while anti-protons have a negative charge, and prositrons also have the opposite charge of the electrons.

18- Matter and antimatter formed in equal amounts when the universe began. But nowadays there is far more matter than antimatter, and we don’t have much information about the antimatter. But why did the matter win the battle?

19- As the universe expanded quickly and cooled, the energy density became too low for the creation of particle-antiparticle pairs, and that should have destroyed all the particles and the antiparticles. But a small fraction (less than one in a billion) of the particles survived and went on to create the matter that is all around us - our bodies, the earth, and the stars we see are all made of matter.

20- Let's end this presentation with a small joke: A neutron walks into a bar and asks: “How much for a drink?” The bartender replies: “For you, no charge”.