Suslin's problem

Okay kiddo, so Suslin's problem is about special sets of numbers that we call linearly independent sets.

Let's pretend we have some blocks of different sizes and colors, for example, red, blue and green. We want to put them together in a certain way so that they fit together perfectly and none of them can be removed without breaking the structure.

In math, we call these blocks "elements" and the structure they make "a set". Now, a linearly independent set is a set where none of the elements can be expressed as a combination of the others.

For example, if we have a red block, a blue block, and a green block, they are linearly independent because we cannot express any of them as a combination of the other two. But if we have two red blocks and a blue block, the red blocks are not linearly independent because we can express one of the red blocks as a combination of the other red block and the blue block.

Suslin's problem asks whether every linearly independent set of a certain type, called a countable set, can be made by combining some basic elements called "generators". This problem has been open for a long time and is still unsolved, which means mathematicians are still trying to figure out the answer!