It's pretty much how every cryptocurrency works, with separation of public (receive) and private (send) keys. The fact that invoices are temporary in LN is a w

It's pretty much how every cryptocurrency works, with separation of public (receive) and private (send) keys. The fact that invoices are temporary in LN is a weakness of the design, not an intentional choice. The lightning network represents a regression from the typical use-case of cryptocurrency because both sender and receiver need to be online to make a payment.