Are there solar systems in which a sun is a planet?

Supposedly, back in the olden days, people believed the earth was the center of the solar system, that is to say that the sun revolved around the earth.

Science says the earth revolves around the sun.

Has science found any systems where a sun revolves around a planet?

I have not heard this theory postulated anywhere. Has this ever happened or is it always a planet revolving around a star?

I think it would have to be one large,hugely dense planet and say..a brown dwarf,but I don't see how it would be inpossible given the infinite amount of systems out there.

Of course people have heard of binary star systems(Two suns orbitting each other.)

AND..not forgetting guitarists.. the whole universe revolves around them