Vector Space of Matrices: How to Define and Illustrate?

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The discussion focuses on defining and illustrating the vector space of matrices using a formal notation similar to that used for functions from a set S to a field F. The user proposes a detailed structure for the vector space, defining operations of addition and scalar multiplication for matrices. They express uncertainty about the correctness of their notation and seek clarification on how to properly represent the vector space of matrices. The conversation highlights the need for precise definitions in linear algebra, particularly when transitioning from functions to matrices. Overall, the thread emphasizes the importance of clear mathematical language in defining vector spaces.
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You know the example "The space of functions from a set S to a field F" that's usually
given in a linear algebra text? Well they never give an example of the set they're working in
in detail so I defined the set as:

((S, (S x S, S, +)), ((F, (F x F, F, +')), (F x F, F, °)), (S x F, F, •))

where:

+ : S x S → S defined by + : (f,g) ↦ (f + g)(x) = f(x) + g(x)
• : S x F → F defined by • : (f,β) ↦ (βf)(x) = βf(x).

&

(S, (S x S, S, +)) is an abelian group of vectors (functions),
((F, (F x F, F, +')), (F x F, F, °)) is the field over which the operations take place,
(S x F, F, •) is the operation of scalar multiplication on vectors (functions).

My questions is: How would I illustrate a vector space of matrices akin to the notation
above?


Since a matrix is just the function f : (i,j) ↦ A(i,j) = Aij (as defined in Hoffman/Kunze anyway!).
I think the function is more generally defined as
f : Fm x n x Fm x n → Fm x n

To translate it into the above language I'm thinking:

((Fm x n, (Fm x n x Fm x n, Fm x n, +)), ((F, (F x F, F, +')), (F x F, F, °)), (Fm x n x F, Fm x n, •))

where

+ : Fm x n x Fm x n → Fm x n defined by + : (i,j) ↦ (A + B)(i,j) = A(i,j) + B(i,j) = Aij + Bij

• : Fm x n x F → Fm x n defined by • : ((i,j),β) ↦ (βA)(i,j) = βA(i,j) = βAij

But that seems weird tbh, is it correct?
 
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? You said you were going to define a set but what you define is not simply a set. A set would be something like "{a, b, c}". What would be the set of functions from that to, say, the field fo rational numbers?
 
I'm just going by the guidelines I've been given in this post:

https://www.physicsforums.com/showpost.php?p=3105066&postcount=7

Maybe the language was a bit loose, re-read the sentence:

"Well they never give an example of the set they're working in in detail so I defined the set as:"

as:

"Well they never give an example of the sets they're working in in detail so I defined the vector space as:"


and hopefully it will make more sense.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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