Clasificación de la Biblioteca del CongresoQC793.P422

American(6) animals(18) astrophysics(71) biography(13) biology(18) cells(16) chemistry(49) children(10) children's(7) computer science(5) cosmology(194) dark matter(7) digital(5) educational(6) engineering(6) environment(6) essay(6) general science(9) geometry(8) God(5) graduate(9) higher dimensions(5) history(71) history of science(65) hyperspace(41) light(27) math(167) matter(20) modern physics(8) natural science(40) nature(16) nuclear(12) parallel universes(19) philosophy of science(7) physics/astronomy(7) physique(23) picture book(21) popular physics(13) popular science(185) popularization(5) quantum(56) quantum mechanics(138) quantum physics(175) reference(37) relativity(61) religion(10) Richard Feynman(12) science(2,037) science and technology(12) science fiction(51) science writing(5) size(23) spacetime(14) spirituality(5) statistics(5) string theory(63) superstring theory(7) superstrings(5) symmetry(37) television(5) theoretical(8) theoretical physics(34) time(24) time travel(22) time warps(9) universe(20) usa(5)