Something is brewing in the open sea and yet the sailor dindnt fear me

I’m traded in whispers, yet weigh nothing at all. I can build up a crown or make kingdoms fall. I travel the fastest when mouths move with ease, and I grow even louder on just one more, please.

I'm completely odd, except at my start. I go on forever, although humanity has mapped me to forty-one million numbers in length. While no pattern exists to define me, a theorem exists to predict my distribution. This riddle reads hard, but truly I'm the only divisible answer.

I can be made of stone, language, or sound, Built to keep limits or keep you aground. Break me to pass or stay on your side, I’m the thin line where two worlds collide.

I'm cold when I'm full, Hot when I starve. When you want your whisky neat, You'll need what my tummy keeps.