How did the universe begin? How can something come from nothing? One way to “solve” this most difficult of philosophical conundrums is to avoid it altogether. Maybe the universe didn’t begin. Maybe the Big Bang was just one in an endless...

We actually have a pretty good idea of what might have happened before the Big Bang. That is, as long as we define the Big Bang as the extremely hot, dense, rapidly expanding universe that is described by Einstein’s equations. That...

In this video Paul Andersen explains how scalar fields can be used to show the distribution of scalar quantities. The most important scalar fields in AP Physics 2 deal with electric potential. Scalar addition can be used to combine...

Dark energy is different than dark matter. They are both labeled dark because we don’t know what they are. Dark matter does not absorb, reflect or emit any light. It is inferred to exist only because of its...

Summary:

The Big Bang theory: In the beginning, the universe was packed tightly together into a point of infinite density. It then exploded into the universe we see today. This is actually...

SUMMARY

What if gravity repelled instead of attracted? Repulsive gravity may have shaped the entire history of our universe. For centuries gravity was defined by Isaac Newton’s Law of Universal Gravitation which...