A continuum is a continuous series or whole, ranging from one end or extreme to the other, with no clear dividing lines or points. Continuums are used to describe everything from the way a rainbow changes colors to the flow of blood in an arm or a foot.

#### Continuum Hypothesis: A Central Open Problem in Set Theory

In the late nineteenth century, Georg Cantor was trying to solve a very important open problem in set theory, called the continuum hypothesis (CH). He believed that it could be solved and that it would be a significant step forward in the development of mathematics.

When Cantor tried to solve the CH problem, he found that it was extremely difficult and frustrating. He also discovered that the solution could not be given in any reasonable manner by using the axioms that were available to him at the time.

Cantor eventually gave up on the problem and stopped trying to find a way to solve it. He regarded the CH problem as a waste of his time and energy and that it was a hindrance to his work.

It was not until the twentieth century that new mathematical methods were developed that enabled mathematicians to resolve the CH problem. These methods allowed for the introduction of a universe of constructible sets, which is now called Godel’s universe.

A universe of constructible sets is a model of the mathematical universe, or set of real numbers. This universe is small enough that it can be made to satisfy all the requirements of set theory, and it can also be made to be consistent with the continuum hypothesis.

Moreover, it is possible to build another universe in which the continuum hypothesis fails, just as it was possible for Godel to do. This is a remarkable accomplishment, but it also raises a lot of questions about the solvability of the CH problem.

The most important question is how we might be able to build a model of the mathematical universe in which the continuum hypothesis fails. This is a very interesting and important question for mathematics, because it shows that we are not stuck with the methods we have today.

In the 1990s, Jorg Brendle, Paul Larson, and Stevo Todorcevic showed that there are three new principles implicit in the continuum hypothesis which, taken together, put a limit on the size of the continuum. These principles are very different from the standard axioms of Zermelo-Fraenkel set theory, which is based on the Axiom of Choice (ZFC).

If these three principles are true, then there is a provable bound on the size of the continuum. The size of the continuum is a central problem in set theory, and it has been a major focus of research for the past two hundred years.

The new ideas in this area have been extremely influential. They are now a staple of set theory and many other areas of mathematics, and they are helping to resolve the most important open problems in the field. These include the continuum hypothesis, the infinity arithmetic problem, and the sigma prime problem.