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The complete history of the Universe -- from the Big Bang to 200 my into the future


History of the Universe eBook. 398 pages, 300 illustrations only $2.99

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Grand Unification Epoch 10-35 to 10-36 seconds

Once gravity had separated out, it is thought that a single field remained, a field which is described by the Grand Unified Theory (sometimes abbreviated to GUT) and hence this period is known as the Grand Unification Epoch. The field is sometimes called the Grand Unification Field or GUT field.

We do not find this field in the world today because, as we will see, it has since broken down into three other fields. These each appeared in turn as the Universe expanded.

The Grand Unification Epoch probably ended at about 10-36 seconds after the creation of the Universe.

Strong Interaction

As the young Universe expanded and the GUT field grew weaker, it quickly decayed and a new field separated from the others. This was the strong interaction. It is the strongest of all four forces. Also called the strong nuclear force, it is the force which holds quarks together to make protons and neutrons, and also holds these particles together to make the nuclei of atoms. So without this force we could not exist.

It is usually attractive, but can be effectively repulsive in some circumstances.

The particles which carry the strong nuclear force are called gluons.

We never normally meet this force in our everyday lives because, despite being very strong, it is also very short-ranged. It acts only over ranges of order 10-15 meters. This force is important inside stars, where it creates starlight, and in nuclear reactors and weapons.

As the strong force separated from the others it left a combination sometimes called the electroweak force.

Electromagnetic Force

As the Universe continued to expand, the electroweak force very quickly decayed and released the second strongest force we find today: the electromagnetic force.

You can stick a balloon to the ceiling by first rubbing it on a woolen jumper.

A balloon sticks to the ceiling by electrostatic force

The force which holds it up is the electric force, which is part of the electromagnetic force. Find out more here.

You can feel the other part of this force, the magnetic force, when you attach a magnet to a refrigerator.

The electromagnetic force is much weaker than the strong force, but we can feel it because it acts over much longer distances.

Weak Interaction

The last force to appear in the young Universe was the Weak Interaction. It is a force within the atomic nucleus that is responsible for a type of radioactivity called beta decay and also for interactions between neutrinos.

It has a very short range and, as its name indicates, it is very weak.

The particles which carry the weak nuclear force are called W and Z bosons.

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History of the Universe eBook. 398 pages, 300 illustrations only $2.99

eBook only $2.99
398 pages, 300 images

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