
KRIPKE-PLATEK SET THEORY AND THE ANTI
... By a ∆0 formula we mean a formula of set theory in which all the quantifiers appear restricted, that is have one of the forms (∀x ∈ b) or (∃x ∈ b). KP arises from ZF by completely omitting the Power Set Axiom and restricting separation and collection to absolute predicates (cf. [3]), i.e. ∆0 formula ...
... By a ∆0 formula we mean a formula of set theory in which all the quantifiers appear restricted, that is have one of the forms (∀x ∈ b) or (∃x ∈ b). KP arises from ZF by completely omitting the Power Set Axiom and restricting separation and collection to absolute predicates (cf. [3]), i.e. ∆0 formula ...
Rational and Irrational Numbers
... set and the result is also a number in that set, the set is said to be closed under the operation. This is called the Closure Property. Determine if each set of numbers is closed under the indicated operation. ...
... set and the result is also a number in that set, the set is said to be closed under the operation. This is called the Closure Property. Determine if each set of numbers is closed under the indicated operation. ...
Issue 5 - CJM - Right Angle
... Natural numbers were natural to our ancestors as they needed to count their sheep. But the discovery of zero had to wait till the concept of “Shunya” of Hindu Philosophy could sink into human psyche. The negative numbers emerged so that a b 0 could be solved for every natural number a . This cre ...
... Natural numbers were natural to our ancestors as they needed to count their sheep. But the discovery of zero had to wait till the concept of “Shunya” of Hindu Philosophy could sink into human psyche. The negative numbers emerged so that a b 0 could be solved for every natural number a . This cre ...
01-12 Intro, 2.1 Sets
... One-to-One Correspondence An important concept in learning numbers is what we call a one-to-one correspondence. ...
... One-to-One Correspondence An important concept in learning numbers is what we call a one-to-one correspondence. ...
Document
... • As number theorists, we are interested in this equation as a Diophantine equation, i.e., we are interested in finding solutions in the natural numbers. Such a (non-trivial) solution is called a Pythagorean triple. • In particular, if a, b and c have no common divisors, then (a, b, c) is called a p ...
... • As number theorists, we are interested in this equation as a Diophantine equation, i.e., we are interested in finding solutions in the natural numbers. Such a (non-trivial) solution is called a Pythagorean triple. • In particular, if a, b and c have no common divisors, then (a, b, c) is called a p ...
factals
... In 1980, the mathematician Benoît Mandelbrot visualized for the first time on a computer many mathematical objects that he called fractals. One of the most popular fractals is the Mandelbrot set, obtained from the iteration of the polynomial function z 2 + c. A few years later, factals images were g ...
... In 1980, the mathematician Benoît Mandelbrot visualized for the first time on a computer many mathematical objects that he called fractals. One of the most popular fractals is the Mandelbrot set, obtained from the iteration of the polynomial function z 2 + c. A few years later, factals images were g ...
Real Numbers - Will Rosenbaum
... Notice that in the above proof, we explicitly state each axiom we apply in the algebraic manipulations. This “two column” proof approach is a good habit to maintain, especially when you are just beginning to write formal proofs. The proof above only references the field axioms, hence the proof is va ...
... Notice that in the above proof, we explicitly state each axiom we apply in the algebraic manipulations. This “two column” proof approach is a good habit to maintain, especially when you are just beginning to write formal proofs. The proof above only references the field axioms, hence the proof is va ...
Non-standard analysis

The history of calculus is fraught with philosophical debates about the meaning and logical validity of fluxions or infinitesimal numbers. The standard way to resolve these debates is to define the operations of calculus using epsilon–delta procedures rather than infinitesimals. Non-standard analysis instead reformulates the calculus using a logically rigorous notion of infinitesimal numbers.Non-standard analysis was originated in the early 1960s by the mathematician Abraham Robinson. He wrote:[...] the idea of infinitely small or infinitesimal quantities seems to appeal naturally to our intuition. At any rate, the use of infinitesimals was widespread during the formative stages of the Differential and Integral Calculus. As for the objection [...] that the distance between two distinct real numbers cannot be infinitely small, Gottfried Wilhelm Leibniz argued that the theory of infinitesimals implies the introduction of ideal numbers which might be infinitely small or infinitely large compared with the real numbers but which were to possess the same properties as the latterRobinson argued that this law of continuity of Leibniz's is a precursor of the transfer principle. Robinson continued:However, neither he nor his disciples and successors were able to give a rational development leading up to a system of this sort. As a result, the theory of infinitesimals gradually fell into disrepute and was replaced eventually by the classical theory of limits.Robinson continues:It is shown in this book that Leibniz's ideas can be fully vindicated and that they lead to a novel and fruitful approach to classical Analysis and to many other branches of mathematics. The key to our method is provided by the detailed analysis of the relation between mathematical languages and mathematical structures which lies at the bottom of contemporary model theory.In 1973, intuitionist Arend Heyting praised non-standard analysis as ""a standard model of important mathematical research"".