Falling Through the Mind

What's left after a flower has died? What's left after a fire burns? What's left once a building has fell? The memory lives on, maybe only by one person, maybe carried on by only the ground that once supported it. Even if all evidence of it ever existing vanishes the air will always remember, and so will the sky, and so will all the carbon atoms it was made out of. So what happens if that something never existed in the physical world? Who carries that on, after the mind decays it's forgotten, can anything truly be forgotten?