例句與造句

1. The set of all such vectors engenders one outgoing and one ingoing null congruence.
2. However, this can be confirmed by direct computation of the optical scalars of the null congruence \ partial _ v.
3. Therefore, pp-waves belong to the Kundt class ( the class of Lorentzian manifolds admitting a null congruence with vanishing optical scalars ).
4. For a better understanding of the previous section, we will briefly review the meanings of relevant NP spin coefficients in depicting null congruences . governing null flows reads
5. As shown in the article " Expansion rate of a null congruence ", the outgoing and ingoing expansion rates, denoted by \ theta _ { ( \ ell ) } and \ theta _ { ( n ) } respectively, are defined by
6. It's difficult to find null congruence in a sentence. 用null congruence造句挺難的
7. Some classes of solutions can be invariantly characterized using algebraic symmetries of the Weyl tensor : for example, the class of non-conformally flat null null dust solutions admitting an expanding but nontwisting null congruence is precisely the class of " Robinson / Trautmann spacetimes ".
8. More precisely, type "'D "'fields occur as the field of a gravitating object which is completely characterized by its mass and angular momentum . ( A more general object might have nonzero higher multipole moments . ) The two double principal null directions define " radially " ingoing and outgoing null congruences near the object which is the source of the field.