Inflaton

[Brainee]

What is an inflaton field?

[joigus]

It is a scalar field that's needed in inflationary models of cosmology to provide a mechanism for the vacuum to go through different phases of expansion.

A scalar field is a field represented by a number at every point of space and every instant of time, so that it doesn't change at all under rotations.

In a way, it's very much like the Higgs field. It affords you to "imprint" needed properties on the other fields and space-time itself to account for observed properties that don't quite fit the model without it. It's considered by some to be somewhat ad hoc --convenient, but not very well understood or logically compelling.

[Mordred]

Good answer +1

[Genady]

Einstein was invited to a dinner where he was asked by a hostess to "be so kind as to explain to my guests in a few words, just what is relativity theory." He said he was reminded of a walk he one day had with his blind friend. The day was hot and he turned to the blind friend and said,
"I wish I had a glass of milk."
"Glass," replied the blind friend, "I know what that is. But what do you mean by milk ?"
"Why, milk is a white fluid," explained Einstein.
"Now fluid, I know what that is," said the blind man. "but what is white ?"
"Oh, white is the color of a swan's feathers."
"Feathers, now I know what they are, but what is a swan ?"
"A swan is a bird with a crooked neck."
"Neck, I know what that is, but what do you mean by crooked ?"
At this point Einstein said he lost his patience. He seized his blind friend's arm and pulled it straight. "There, now your arm is straight," he said. Then he bent the blind friend's arm at the elbow. "Now it is crooked."
"Ah," said the blind friend. "Now I know what milk is."