In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

Let me give you an example: In one work this author details the life of a tomb-maker who makes extra money by playing the organ at an insane asylum, while another of his novels sees Swartz give a refugee proper documentation only after he tells him his life story in the title Portuguese city. In addition to The Black Obelisk and The Night in Lisbon, he also wrote about Robert and Otto selling their auto workshop and visiting Patrice in a Swiss tuberculosis sanatorium in his novel The Three Comrades, while the turbulent life of the German surgeon Ravic is told in The Arch of Triumph. Another of his novels, The Road Back, is thought to be a sequel to his most famous book, in which the patriotic teacher Kantorek convinces Paul Bumer and his friends to join the Germany Army during World War I. For 10 points, name this German author who wrote All Quiet on the Western Front.
The answer to this example can be: Literature
Here is why: The text is talking about an author and their works, so it belongs to theliterature category.

OK. solve this:
Mssbauer spectroscopy involves the observation of phenomena including isomer shifts and this. An equation describing it contains an electron spin g-factor of approximately two. It was first observed by its namesake in the D lines of sodium and its anomalous variety occurs when electron spin contributes to this phenomenon. A potential energy associated with it is proportional to the Bohr magneton, the Lande g-factor, and the z component of the total momentum. This is the magnetic analog to the Stark effect, and in strong fields it becomes the Paschen-Back effect. The inverse type of it considers absorption lines as opposed to spectral lines. For 10 points, name this splitting of spectral lines in a magnetic field.
Answer:
Science