The Earth's mass is 6,615,000,000,000,000,000,000 tons. There are many arguments about how big the universe is. Some astrologists and cosmologists say that we live in one universe that is part of a multiverse, meaning that this universe isn't the only one. I don't think anybody has a definitive answer for that question, yet. As for what happens when we die; it depends on how we die. If it's only humans that die out somehow, then life will continue without us, the Earth will heal and the other animals will be able to roam freely again.
The world as in the earth has measurements, theres no debating on how large it is....the universe however is infinate if thats what your thinking off. When humans cease to exist, i dont believe anything special happens. The world goes on and continues living without us.
I think we rot in the ground and become soil to feed a beautiful tree :) haha
we die we wait till the day of judgement!