Decomposable Tensors Problem: V Vector Space Dim ≤ 3

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In a vector space V with dimension less than or equal to 3, every homogeneous element in the exterior algebra Λ(V) is decomposable. A homogeneous element is defined as a form of definite degree, while a decomposable form can be expressed as the exterior product of two forms of lower degree. Examples discussed include the case for dimV=2, where homogeneous elements belong to IK, T^1(V), or T^2(V). It is confirmed that a decomposition can involve forms of equal degree, but if both forms are in T^1(V), their product will yield a form in T^2(V). Understanding these definitions and properties is essential for solving the decomposable tensors problem.
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Problem:
V a vector space with dimV \le 3, then every homogeneous element in \Lambda(V) is decomposable.


So, this exercise doesn't sound very difficult. My problem is, that i don't know the definition of homogeneous and decomposable. Can you please help me?
Thank you
 
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A homogeneous element of \Lambda(V) is a form of definite degree, p. A decomposable form is one that can be written as a single exterior product of two forms of lower degree \omega = \mu \wedge \nu.
 
Hello,

Thank you for your help!
are these examples correct?:
For dimV=2 We have \Lambda(V) = IK \times T^1(V) \times T^2(V).

-Then a homogeneous elm. would be all elm. in v\in \IK or v\in T^1(V) or v\in T^2(V).
Where T is the Alternator.

-Is it allowed to use the single exterior product of two form of equal degree, i.e. v=\mü \wedge \tau with v,\mü,\tau \in T^1(V) for instance?


Thanks
 
Canavar said:
Hello,

Thank you for your help!
are these examples correct?:
For dimV=2 We have \Lambda(V) = IK \times T^1(V) \times T^2(V).

-Then a homogeneous elm. would be all elm. in v\in \IK or v\in T^1(V) or v\in T^2(V).
Where T is the Alternator.

Yes a homogeneous element would be in T^p(V) for some p.

-Is it allowed to use the single exterior product of two form of equal degree, i.e. v=\mü \wedge \tau with v,\mü,\tau \in T^1(V) for instance?

Yes it is possible that the decomposition involves forms of equal degree. However, in your example, if \mu, \tau \in T^1(V), then v= \mu \wedge\tau\in T^2(V).
 
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