Any lawyer will tell you that "authentic" is an excellent weasel-word, beloved of fraudsters and shady dealers for decades, due to its two possible meanings. In common usage it can mean either "genuine" or "realistic", depending on context. Keep the context ambiguous, and the claims for genuineness of the "authentic" item are equally ambiguous.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis