41. When there are external lines, the amplitudes are antisymmetric when two Fermi insertions for identical particles are interchanged. 42. In other words, in an antisymmetric state two identical particles cannot occupy the same single-particle states. 43. A possible alternative to the antisymmetric explanation could be based on the difficulty of parsing languages with rightward movement. 44. These results imply that Universal Grammar is equipped with the binary head-directionality, and is not antisymmetric . 45. This is not satisfactory for fermions, such as electrons, because the resulting wave function is not antisymmetric . 46. We can construct symmetric and antisymmetric multi-particle states out of continuous eigenstates in the same way as before. 47. For the former case, the trivial representation could either lie in the symmetric product, or the antisymmetric product. 48. Within the Hartree Fock method of quantum chemistry, the antisymmetric wave function is approximated by a single Slater determinant. 49. By comparison with the solutions above, we can see that only the antisymmetric ones have nodes at the origin. 50. What this means is that the wave equation must also be antisymmetric with respect to the exchange of two electrons.
