THERE IS NO BITCOIN. Definitely not physical, but not even virtual! The closest thing is a wallet.
Bitcoin is nothing more than a ledger of transactions. You can't own a bitcoin. You can only own a wallet that has transactions associated with it. You create a wallet with a public and private key. The public key is what people use to increase your ledger count. The private key is what you use to decrease your ledge count by increasing someone else's ledger count..
It's like a fancy excel spreadsheet that tracks debits and credits.
Every time you close off a group of transactions in the ledger there is a pre-determined reward for the group that finds the hash. That reward is an increase in there ledger. That is the ONLY time new ledger entries are allowed that don't have an equal decrease in someone else's wallet.