Remove unnecessary hyphen

Author: hollasch

books/RayTracingTheNextWeek.html

@@ -1838,7 +1838,7 @@
 Rectangles and Lights
 ====================================================================================================
 Lighting is a key component of raytracing. Early simple raytracers used abstract light sources, like
-points in space, or directions. Modern approaches have more physically-based lights, which have
+points in space, or directions. Modern approaches have more physically based lights, which have
 position and size. To create such light sources, we need to be able to take any regular object and
 turn it into something that emits light into our scene.