Detailed Instructions: 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.
Q: They are divided into two classes based on the ratio of the penetration depth to the coherence length, a quantity known as the Ginsburg-Landau parameter. Alexei Abrikosov discovered his namesake vortex lattice in one type, and the London equation describes a characteristic behavior of these materials similar to perfect diamagnetism. A complete theory of the type I variety of these substances, including the concept of the pairing of opposite-spin electrons over long distances, is known as the BCS theory. Discovered by Heike Kammerlingh-Onnes, FTP, identify these substances which exhibit zero electrical resistivity.
A:
Science