# Group theory

Welcome to Group Theory!

Group Theory is a vibrant, wide area of current research in mathematics, computer science and mathematical/theoretical physics. There are many applications of group theory to the study of geometric objects, to topology and in many cases their links to other branches of algebra are quite well understood.

So, why study group theory?

You might study it because you've got a research question that somehow involves symmetry --- constraint problems in computer science can be solved more efficiently when a little's known about the solution space. You might need to make some difficult calculations in a complicated topological space which become easier by passing into structures called their fundamental groups.

You might even want to make millions as a cryptographer --- current methods in cryptography are hard to crack, but become very easy when hacking with a quantum computer. There are good reasons to hope that groups hold the key to codes that can't be broken easily by quantum computers, just in case someone invents one and fancies stealing your identity. We've just not come up with the perfect code yet.

Perhaps you just want to study it because it's fun and not really difficult to get into. Group theory can be understood at a moderate level by high-school level students, and in fact well enough by interested undergraduate students for them to produce original research. This is in stark contrast to the New Math introduced in American high schools in the mid-20th century, which consisted of teaching young teenagers abstract subjects like Set Theory and in certain cases Category Theory, both of which are very difficult to get an idea about without a solid grounding in undergraduate mathematics.

It's also a very beautiful subject. Many familiar mathematical objects are some sort of group - some in more than one way. Understanding a little about groups can make it easier to understand these objects too.

## Learning materials and learning projects[edit]

Wikiversity has adopted the "learning by doing" model for education. Lessons should center on learning activities for Wikiversity participants. Learning materials and learning projects can be used by multiple departments. Cooperate with other departments that use the same learning resource.

Learning materials and learning projects are located in the main Wikiversity namespace. Simply make a link to the name of the lesson (lessons are independent pages in the main namespace) and start writing!

## Offsite Learning Materials[edit]

- Abstract Algebra - Free Harvard Courses
- Group Theory - Basic notes from Dr. Ben Lynn, main author, developer and maintainer of Stanford's PBC Library
- Printable Abstract Algebra (group theory) flash cards

## Active Participants[edit]

If you are an active participant, feel free to put your name down here so that students can contact you.

- Thefrettinghand 21:20, 12 July 2010 (UTC)
- Aravind V R (discuss • contribs) 09:10, 23 March 2014 (UTC)
- MikeDoyle (discuss • contribs) 13:59, 7 June 2017 (UTC)

## See also[edit]

- w: Group Theory
- Groups at Wikibooks.