As far as i understand Monero currently uses range proofs (Soon to be bulletproofs) to prove that when an amount of Monero is sent that amount is between 0 and some large number. this is to protect against negative amounts being sent
My question is can Monero range proofs or bulletproofs for that matter prove that a public key owns a certain amount of Monero. for example can i create a construction that a third party can verify that i have say between 50 and 100 XMR
As far as my research goes the only way to prove balance in accounts is to provide view keys and a set of signed key images to a third party, is this still the only way to do this?
Looking forward to any input Thanks