Proving Non-Simplicity of Algebra with Two Generators

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SUMMARY

The discussion centers on proving that a Lie algebra generated by only two elements cannot be simple. Participants clarify that the term "algebra" likely refers specifically to "Lie algebra," as examples like quaternionic fields and matrix algebras challenge the simplicity condition. The conversation highlights the necessity of understanding structure constants and the implications of the Bianchi identity in this context. Ultimately, the consensus is that the proof should focus on Lie algebras, particularly using the structure of sl2 as a foundational concept.

PREREQUISITES
  • Understanding of Lie algebras and their properties
  • Familiarity with structure constants in algebraic contexts
  • Knowledge of the Bianchi identity and its applications
  • Basic concepts of central simple algebras
NEXT STEPS
  • Research the properties of simple Lie algebras, particularly sl2
  • Study the implications of the Bianchi identity in Lie algebras
  • Explore examples of central simple algebras and their characteristics
  • Investigate the role of structure constants in determining algebraic simplicity
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Mathematicians, algebraists, and students studying Lie algebras, particularly those interested in the properties of algebraic structures and their simplicity conditions.

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Hi,
I have been asked to prove that an algebra with only two generators can not be simple. I have thought about it and have tried to show that one of the two structure constants go to zero in the Lie algebra condition that [xi,xj]=sumoverk Cijkxk , but I can't find any way to show that (using the Bianci Identity, for example), and perhaps I am thinking about it the wrong way. I have also tried to think about it logically - perhaps it contains the identity for some reason and any algebra containing the identity is not simple.
I would appreciate any hints people might give me.
 
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You can't mean just 'algebra', can you? The quaternionic fields are algebras and have 2 generators. They are skew fields, hence simple (no ideals), indeed they are central simple algebras, aren't they?

Perhaps you mean 'Lie Algebra'? Indeed you must mean something other than 'algebra' by your last assertion that any algebra with an identity is not simple (the full matrix algebra of nxn matrices over some field is simple and has an identity).

Simple lie algebras are copies of sl_2 glued together. That's one starting point, I don't know how far it'll get you.
 
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Hi Matt,
From what you say it must be Lie Algebras that I have to prove it for. The question just said "prove that an algebra...", but the title of the questions in general says "Lie Algebras". I was unsure at first, but decided he must mean Lie Algebra for that question. Sorry I didn't specify. I will think about sl2 idea.
 

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