Determinant Identity for A-B and B A Matrices

In summary, the conversation discusses the existence of an identity for the determinant of a block matrix composed of two square matrices A and B. The participants suggest resources such as a website and Wikipedia for finding the answer. They also mention that in the specific case they are interested in, the matrices do not commute and may not be invertible. Despite this, they believe the determinant to be nonzero and positive and are trying to find a pattern between different sizes of matrices.
  • #1
quasar987
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Hello matrices masters,

If A and B are nxn square matrices, is there an identity for the determinant of the block matrix

A -B
B A

?

Lots of thanks and praises.
 
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  • #2
Would http://www.mth.kcl.ac.uk/~jrs/gazette/blocks.pdf be able to help you out?
 
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  • #4
Unfortunately, in the particular case I'm interested in, I don't see a reason to believe that A and B commute, nor that A or B is invertible. So none of the formulae on wiki are applicable.

I know for a fact that the determinant of that matrix is nonzero, and it is probably positive, which I am trying to show.
 
  • #5
Did you try finding a pattern between the 2x2, 4x4, 9x9?
 

FAQ: Determinant Identity for A-B and B A Matrices

What is the Determinant Identity for A-B and B A Matrices?

The Determinant Identity for A-B and B A Matrices is a mathematical property that states that the determinant of the difference between two matrices (A-B) is equal to the determinant of the product of those matrices (B A).

How is the Determinant Identity for A-B and B A Matrices used in scientific research?

The Determinant Identity for A-B and B A Matrices is commonly used in linear algebra and matrix calculations. It allows scientists to simplify complex calculations involving matrices, making it a valuable tool in various areas of scientific research such as physics, engineering, and economics.

Can the Determinant Identity for A-B and B A Matrices be applied to any type of matrices?

Yes, the Determinant Identity for A-B and B A Matrices is applicable to any square matrices, regardless of their size or the elements they contain. It is a fundamental property of matrices that holds true for all cases.

What are the implications of the Determinant Identity for A-B and B A Matrices in real-world applications?

The Determinant Identity for A-B and B A Matrices has many practical implications in real-world applications. For example, it is used in engineering to solve systems of linear equations, in economics to analyze input-output models, and in physics to study quantum systems.

Are there any limitations to using the Determinant Identity for A-B and B A Matrices?

One limitation of the Determinant Identity for A-B and B A Matrices is that it can only be applied to square matrices. Additionally, it is not always the most efficient method for solving matrix problems, so other techniques may be preferred in certain situations.

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