The Selected Works of T. S. Spivet include drawings, charts, and lists accompanying the written elements. These drawings are purported to be done by T.S. himself, who also provides each with an explanatory caption that deepens the book's narrative. This is designed to mimic T.S.'s own habit of quantifying the world around him using cartography. Larsen has stated that this technique was not originally intended to be included in the book's format, finishing a complete first draft of the work before he "discovered the margins as a playground of T.S.’s mind." Larsen's parents were both visual artists (his mother a painter and photographer, his father a printmaker),
Solving the geodesic equations curve γ("s") in formula_1 and formula_5 are the Christoffel symbols. The Christoffel symbols are functions of the metric and are given by: where the comma indicates a partial derivative with respect to the coordinates: As the manifold has dimension formula_8, the geodesic equations are a system of formula_8 ordinary differential equations for the formula_8 coordinate variables. Thus, allied with initial conditions, the system can, according to the Picard–Lindelöf theorem, be solved. One can also use a Lagrangian approach to the problem: defining and applying the Euler–Lagrange equation. As the laws of physics can be written in any coordinate system, it