Published online by Cambridge University Press: 05 November 2012
So I asked her the nearest way to Learning's home…. Ask for the direct road, she said, from here to Suffer-both-weal-and-woe-if you are willing to learn that lesson. Then ride past Riches, and dont stop there, for if you become attached to them you will never reach Learning. And avoid the lecherous meadow that is called Lust; leave it a good mile or more to the left, and continue till you come to a mansion called Keep-your-toungue-fromlying- and-slander-and-your-mount-from-spicy-drinks. There you will meet Sobriety and Simplicity of-Speech, and while they are with you every man will be glad to show you his wisdom. So you will come to Learning, who knows most of the answers.
Taken from the 14th century text Piers the Ploughman by William LanglandIn this chapter we define a Clifford algebra in a flat space-time of arbitrary dimension and find its irreducible representations and their properties. This enables us to find which types of spinors are allowed in a flat space-time of a given dimension and signature. We will find that in a space-time of even dimension D, a generic, that is, Dirac, spinor has 2D/2 complex components; however, for certain dimensions and signatures this representation is not irreducible. In these cases we can place restrictions on the Dirac spinor and find spinors which are called Majorana, Weyl or Majorana-Weyl spinors.
The starting point for the construction of a supersymmetric theory is the supersymmetry algebra which underlies it. Supersymmetry algebras contain supercharges which transform as spinors under the appropriate Lorentz group. Hence, even to construct the supersymmetry algebras, we must first find out what types of spinors are possible in a given dimension and what are their properties. We will find in section 5.5 and chapter 10 that supersymmetric algebras and the supersymmetric theories on which they are based rely for their existence in an essential way on the detailed properties of Clifford algebras, which we will derive in this chapter.
To save this book to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.