Yes, that’s how every real cryptocurrency works for now. It’s public\private keys cryptography. Anyone with a private key to your wallet has full access, even if he “guessed” this key.
“Sending password” does not exist on the blockchain, it only exists in your local Daedalus installation, to protect you from someone else stealing your computer (or gaining access to it) and sending all your coins. You may have Daedalus installed on multiple computers and have the same wallet restored on each of them but with different passwords.
Private keys (12 words) is the only thing, required to gain full access to a wallet.
2048 words. Which gives you 2048^12 = 2^132 possible keys. So the chance to get a key from existing wallet just by chance is
It is more probable to win all the lotteries on the planet at once, and also to be stricken by lightning at the same moment
Technically there’s no such thing as non-existing wallet. All wallets are like a field of possible values. Imagine each wallet to be just a number between 0 and 2^132 - they all already exist in the same way as all integer numbers exist
All the wallets are already here, the question is - does someone already has keys from a specific wallet? For 99.99999999…% of wallets - no. There’s not a single person in the world that would have the key from it. But the wallet itself exists. Does a number that no one has ever written down exist? The same thing with a wallet that no one has keys from =)
Each wallet additionally has 2^64 possible addresses. If you take any single wallet - there’s 2^64 addresses related to it, and if you send coins to any one of those addresses - you will see these coins as balance for this wallet in Daedalus.
So at any point in time - there are
(2^132 * 2^64) = 2^(132+62) = 2^194 Cardano addresses that do already exist. Each and every one of them may be watched in cardanoeplorer.com - and for 99.99999999999999999999999999999999999…% of them - there will be zero balance
Every time you write down, or input in Daedalus, or just imagine 12 valid words (from those 2048) - you get potential access to one of those 2^132 wallets and to 2^62 of those 2^194 addresses. And if there are some coins on any of those 2^64 addresses - you may spend it.
Hope it helps )
Some decimal numbers just to mess with the brain
Number of all possible Cardano wallets = 5’444’517’900e+30
It is ~5,5 billions with additional 30 zeroes after it.
Number of addresses for each wallet = 1’844’674’400e+10
It is ~1.8 billions with additional 10 zeroes after it.
Number of total possible addresses = 25’108’407’000e+48
It is ~25 billions with additional 48 zeroes after it.