Non-relativistic $k$-contractions of the Coadjoint Poincar\'e algebra

Understand

We study a class of extensions of the k-contracted Poincar\'e algebra under the hipotesis of generalizing the Bargmann algebra and his central charge.

• As we will see this type of contractions will lead in a natural way to consider the codajoint Poincar\'e algebra and some of their contractions.
• Among them there is one such that.
• considering the quotient of it by a suitable ideal, the (stringy) p-brane Galilei algebra is recovered.