There's a story in a collection of sci-fi short stories (translated to Slovene), it would be cool if you could help me identify its name and author.
A zoologist is chosen by a galactic empire to go on a journey with their spaceship together with some earth animals. His task is to take care of these animals. Upon his arrival back home, he wrote a book about his adventures on their spaceship (he was the first one of mankind to be allowed to enter it) and is being constantly supervised by the united earth government because his cooperation with the Galactics is suspicious to them.
The Galactics decide to translate his work and publish it galaxy-wide; it becomes a bestseller and he gains some Galactic credits (the name of their currency) as provision. By contrast, he becomes subject to much hatred among mankind as his book is a source of ridicule towards primitive earthlings. Some of the Galactics even decide to visit Earth as tourists but don't spend any money, which can be compared to 19th century western expeditions to areas populated by primitive tribes.
Now the Earth government decides to tax his income, and he is forced by the Earth government to sign another contract with Galactics. I don't remember exactly how, but he is invited to the Galactic council on the Earth to sign this contract, but it turns out that he needn't sign it at all (or if you take it the other way around, a signature is not authentic enough), he just needs to express his will. It is stored in matter, and that guarantees authenticity.
He takes one of the UBI (UN verion of FBI) officials to make him realize that the Earth government can't take his income under any condition, but he is the one to place them.
I'm interested in this, because the concept of information being stored irreversibly in a matter reminds me to quantum encryption (see some fresh news on it: http://www.kurzweilai.net/achieving-quantum-based-secure-communication).