Hi,

I'm writing a scifi novel set about 150 years from now, where digital coin is standard.

Part of the plot needs the hero to join the dots from a single bitcoin-like transaction to other clues.

I wanted to ask:-

1) is it possible to trace the expenditures / receipts relating to a single public key via the blockchain?

2) is it possible to trace movements of bits from one public key to another to form a relational "tree" of where money has come from / gone?

3) what kind of mechanisms would someone use to "launder" bits, so they were clean? I don't really care how it works at the binary level, just need to know the names / basics of some techniques.

I don't want to trace back to whoever owns the key, just to know if you can link / see other connected Transactions, and if hey can be obfuscated. It's one piece of a larger real-world puzzle.

Not a bitcoin expert – I want to get these details right to avoid nerdflames.

Thanks for your help.