ABSTRACT MULTILINEAR
ALGEBRA
BY
GYULA RÁBAI
WHAT IS A NUMBER?
WHAT IS A NUMBER?
An element of
:
ALGEBRAIC STRUCTURE
OF NUMBERS
Commutative Ring
Field
Free Commutative Monoid
SET
There exists a set M
[Name]
NON-EMPTY SET = SET +
ELEMENTS
There exists a set M
where a and b
are elements of M,
[Name]
[Elements]
PARTIAL MAGMA = NON
-EMPTY SET +
BINARY OPERATION
There exists a set M
where a and b
are elements of M,
[Name]
[Elements]
and there exists an operation on some a and b
[Bin-arity]
MAGMA = PARTIAL MAGMA +
TOTALITY
+
CLOSURE
There exists a set M
where a and b
and c
are elements of M,
[Name]
[Elements]
and there exists an operation on
e
very
a and b
that results in c
[
Total
Bin-arity]
[
Closure
]
MAGMA = PARTIAL MAGMA + TOTALITY +
CLOSURE
There exists a set M
with e
lements
a and
b
[Set]
The result of an operation on any a and
b is in M
[
Total
Binary
Closure
]
UNITAL MAGMA = MAGMA
+
IDENTITY
There exists a set M with elements a and b
[Set]
The result of an operation on any a and
b is in M
[Total
Binary Closure]
There exists an id
entity element e such that e
compose any other element is
itself.
[
Identity
]
MONOID = UNITAL MAGMA +
ASSOCIATIVITY
[Set]
[Total
Binary Closure]
[Identity]
[
Associativity
]
MONOID EXAMPLE -
COMMUTATIVE MONO
ID = MONOID
+
COMMUTATIVITY
[Se
t]
[Total
Binary Closure]
[Identity]
[Associativity
]
[
Commutativity
]
COMMUTATIVE MONO
ID
–
EXAMPLE N
MOD 4
FREE MONOID OF A
COMMUTATIVE
MONOID
NATURAL NUMBERS
=
FREE
COMMUTATIVE
MONOID
Counting numbers without
counting!!!
WHERE ARE WE?
COMMUTATIVE MONOID
COMMUTATIVE GROUP = COMMUTATIVE
MONOID +
INVERSIBILITY
[
Inversibility
]
COMMUTATIVE GROUPS
Monoid:
Group:
WHERE ARE WE?
FIELD = C GROUP + C GROUP +
DISTRIBUTIVITY
[Distributivity]
WHERE ARE WE?
RING
USEFUL AXIOMS
A
ssociativity
C
ommutativity
I
dentity
D
istributivity
(
Inversibility
)
WHAT IS A VECTOR?
VECTOR SPACE = ACID + (BASE) FIELD
A
ssociativity
C
ommutativity
I
dentity
D
istributivity
Also inverse with scaling by
-1; Associative with scalar
mul
;
neutral to 1x but… could not be bothered
to
late
x
it
)
MATRICES ARE VECTORS! (RUNNING OUT
OF LATEX)
M+0 = M
M+N = N+M
(M+N)+P= M+(N+P)
s(M+N)= sM
+
sN
(real proof where
we define a matrix
as a mapping between V
is
pretty much the same)
Polynomials
,
waves, continuous functions, arrows, forces and many more are also vectors
LINEAR ALGEBRA IN 2
SLIDES ^^^
MULTILINEAR ALGEB
RA?
•
Tensor product
(x)
•
Distributivity
((u+v
) prod w = …) and (u prod
(
v+w
) = …)
•
Scalars move anywhere.
DONE