So we spend our life on earth, from infancy in school through adulthood learning about how things work, math, and they teach us in school, plus about God, etc, etc, etc. So will fill our minds up with all kinds of knowledge. Them when we die. The brain, (mind) (supposedly) dies and rots. My question is what happens to the knowledge that we had? Is any of it retained when we are made new, in heaven? Someone once told me, that there are no tears in heaven, there for if we have knowledge in heaven of life back on earth we would probably weep. So probably the "knowledge" won't be there. I guess, that's just an opinion. How does the mind, spirit and soul relate? Also brings up questions, like will I know the loved ones that I knew on earth, in heaven? I welcome all thoughts and opinions from scholars on this site.

In the story of Lazarus, the Rich man knew who Lazarus was, and Lazarus knew who the rich man was. Both knew who Abraham was.
We do know we won't be married to our earthly spouses.
Matt 8:11 says Abraham, Isaac and Jacob will be in heaven, seemingly recognizing each other. (Also see Luke 13:28)
In the story of Saul and the seer, 1Sam 28:7-20 ; when Samuel came back to life, he knew who Saul was.
In Luke 9:30-33 I'm not sure how the apostles knew who the two people talking to Jesus were.

It's a great question, and it's hard to know for sure, but I believe we will remember some things.

1Co 13:12 For now we see through a glass, darkly; but then face to face: now I know in part; but then shall I know even as also I am known.

Our thoughts, experiences, and knowledge, make up who we are and will remain part of us.