transferGW -- the transfer of Grothendieck-Witt from an étale algebras to a base field

• Usage:

  transferGW(beta)

• Inputs:
  • beta, a Grothendieck-Witt Class, Grothendieck-Witt class over an étale algebra over field of characteristic not 2
• Outputs:
  • a Grothendieck-Witt Class, the image of the Grothendieck-Witt class beta in $\text{GW}(k)$ under the canonical transfer map.

i1 : R = QQ[x]/(x^2 - 1);

i2 : beta = makeGWClass matrix(R, {{1,2},{2,x}});

i3 : transferGW(beta)

o3 = | 2 0  |
     | 0 -8 |

o3 : GrothendieckWittClass