Half Girlfriend's principal photography began in 2016.
 It captured the three color components in a multi-layer emulsion
One half also figures in the formula for calculating figurate numbers, such as triangular numbers and pentagonal numbers:                                          n            2                                                [                                          (                                  s                                    2                                )                            n                            (              4                            s              )                        ]                                {\displaystyle {\frac {n}{2}}{\left[\left(s-2\right)n-(4-s)\right]}}  and in the formula for computing magic constants for magic squares                              M                      2                          (        n        )        =                              n            2                                    (                                    n                              2                                      +            1                    )                      {\displaystyle M_{2}(n)={\frac {n}{2}}\left(n^{2}+1\right)}  The Riemann hypothesis states that every nontrivial complex root of the Riemann zeta function has a real part equal to 1/2

