In this paper, we continue our program, started in [2], of building up explicit generalized Euler angle parameterizations for all exceptional compact Lie groups. Here we solve the problem for E7, by first providing explicit matrix realizations of the Tits construction of a Magic Square product between the exceptional octonionic algebra J and the quaternionic algebra ℍ, both in the adjoint and the 56-dimensional representations. Then, we provide the Euler parametrization of E7 starting from its maximal subgroup U = (E6 × U(1))/ℤ3. Next, we give the constructions for all the other maximal compact subgroups. © 2011 International Press.
E7 groups from octonionic magic square
CACCIATORI, SERGIO LUIGI;
2011-01-01
Abstract
In this paper, we continue our program, started in [2], of building up explicit generalized Euler angle parameterizations for all exceptional compact Lie groups. Here we solve the problem for E7, by first providing explicit matrix realizations of the Tits construction of a Magic Square product between the exceptional octonionic algebra J and the quaternionic algebra ℍ, both in the adjoint and the 56-dimensional representations. Then, we provide the Euler parametrization of E7 starting from its maximal subgroup U = (E6 × U(1))/ℤ3. Next, we give the constructions for all the other maximal compact subgroups. © 2011 International Press.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.