Fields

It is believed that the newly formed Universe contained a field.

A field is a physical quantity which has a value, and perhaps a direction, at each point in space. If there is just a value but no direction, then the field is called scalar. A familiar example is a map of rainfall, where each point has the number of inches or centimeters of rain, but there is no direction associated with this number.

If there is also a direction then it is a vector field. A familiar example is a weather map showing the winds, giving both strength (a number) and direction.

Vector and Scalar Fields

Physicist's View of the Universe

From the point of view of physics, everything is a field, so the universe just consists of numbers! A physicist could easily imagine that the universe is nothing but a program running in some vast computer. There seems to be no way of proving whether this view is correct or not.

Inflaton Field

The young Universe could not possibly have contained the sorts of things we see around us today, and yet it was not completely empty. Therefore scientists propose that it contained a scalar field.

The exact nature of the field is not known, but it is often called the "inflaton" field because, as we shall see, it quickly led to a process called inflation. We do not see this field in the world today.

The value of the inflaton field is believed to have been varying very rapidly at every point in space. It was a scalar, positive in some places and negative in others. Strangely enough the average value of the field was zero, which is why the space can be described as a vacuum. But that did not stop the field from containing a large amount of energy due to its fluctuations!