I have a library client looking for a ScFi book he has read before, that he is sure is titled simply "On". It is about gravity shifting 90 degrees. We have not been able to find it, either in our collection or online. Does anyone recognise this title, and perhaps know the author?
Adam Roberts, "On"
The story follows the life of an adolescent named Tighe (pronounced, roughly, Tig-Hee). Tighe's village is built on the ledges and crags of an enormous cliff-face, called the Wall or the World-wall. Every morning, the sun rises from the bottom of the wall, and every evening it sets at the top.
...gravity once pointed towards the centre of the earth, but catastrophically changed due to mankind's over-dependence on Zero Point Energy as an energy source.