MHF 4102 - AXIOMATIC SET
THEORY
FLORIDA
INT'L UNIV.
Review for Test #2 (Jan. 6th)
FALL 2009
REMEMBER TO BRING AN 8’’x11” BLUE EXAM
BOOKLET FOR THE TEST
KEY
CONCEPTS AND MAIN DEFINITIONS:
Ordinal addition, Ordinal multiplication,
Ordinal exponentitaion, Properties of the Cumula-
tive Hierarchy, Cantor's Normal Form, weak
& strong Goodstein sequences, Continuous
ordinal functions, increasing ordinal
functions, Normal functions, Fixed-points of a function,
Equipotent (equipollent) sets, The sizes of N,
Z, A, R, C, NxN, F(N,2), P(N), PFIN(N),
SEQ(N), SEQFIN(N), and F(N,N); Initial ordinals
(Cardinals), The Hartog number of a set,
The alephs, Cardinal addition &
multiplication, Cardinal exponentiation, Axiom of Choice,
(AC), Well Ordering Principle (WOP),
Zorn's Lemma, Contniuum Hypothesis (CH),
Generalized Contniuum Hypothesis (GCH),
The cofinality of a limit ordinal, Singular & Regular
cardinals, Weakly & Strongly inacessible
cardinals, Non-well-founded sets (hypersets),
--------
The Transfinite Partition Algorithm, The
minimal representation of a hyperset.
MAIN
PROBLEM SOLVING TECHNIQUES:
1. Proving various
statements about ordinals by using transfinite induction. and
various statements about the cumulative
hierarchy by using transfinite induction
2.
Simplifying expressions involving Ordinal arithmetic.
3. Expressing ordinal numbers in
various bases (base 2, base omega)
4. Finding
the least fixed-point and other fixed-pointsof
various normal functions
5.
Proving cardinality results by using injections & bijections
6.
Proving various results by using Cantor's Diagonal Argument
7.
Proving various results by using the
Cantor--Bernstein & Squeezing Theorems.
8. Proving results by using the Axiom
of Choice & by using the Well Ordering Principle.
--------
9. Finding the minimal
representation of a hyperset.
10. Determining if two hypersets are
equal.
MAIN THEOREMS
1.
The Fixed-point Theorem for Normal functions
2. The Cantor Diagonal
Theorem
3.
The Cantor-Bernstein Theorem
4. If K & M
are infinite cardinals, then K+M = K.M = max{K,M}.
5.
If 1 < M < K+, then MK = 2K for all infinite
cardinals K.
6. The
Axiom of Choice is logically equivalent to the Well Ordering Principle.
7. For any ordinal
a, cof(2alepf sub a)
> aleph sub a.