The diffferences between worlds

In my book, the characters Digory and Polly have rings that take them to some kind of land/island. When they reach the island, there are millions and millions of mini pools. Each pool leads you to a different world. The world that Polly and Digory went to is completely different than the world that they live in. The world that they are in has a huge sun that is red and all the buildings are in ruins, basically. No one was out there to give them a friendly welcome. It was like a ghost town. The world that Polly and Digory live in is our world with the small, yellow sun and the people. The person that Polly and Digory met from that world wasn't too friendly either. On page 79, it states, "They are not interested in things or people unless they can use them; they are terribly practical." This statement shows that some people from this world have no interests in anything unless they can use them. The person they met also ignored people that wouldn't be able to give them what they want.