Each improve towards the ledger is cryptographically signed to establish that the individual transferring bitcoins is the particular proprietor. No you can expend coins two times since after a transaction is recorded within the ledger, just about every node within the network will learn about it. manuscript by Geir Vigfusson, https://sethbgggi.activoblog.com/29026049/manual-article-review-is-required-for-this-article