How to set up REGEX that doesn't match anything?

Question

Just for curiosity.

Is it possible to create a regular expression that will not match any string, including an empty string?

Answer 1

Yes.

Here are a few examples.

.^
$.
(?!)

Naturally, there are an infinite number of such expressions.

Answer 2

This regex should never match anything (provided you do not use single-line or multi-line modifiers):

$x^