Another Science Post–on Dark Matter

No, I am not referring to the content, minute as it is, of Tim Walz’ brain.  As most of you probably know, the predominant theory of the universe’s evolution is the “Big Bang”.  The universe started small and experienced a period of explosive growth and appears to continue to be accelerating in all directions.  It is hard to wrap your head around the idea of space itself expanding, as we experience and think of everything as being located in “space” and we want to think that if space is growing, it is growing in something.  A lot of research has been done on the remnants of the “big bang” and what those tell us about the universe’s expansion to date, whether it is accelerating or not and other questions.  Scientists have also developed other methods, such as gravitational lensing, to try and understand what the universe as a whole and our local part of it, are doing.

One thing that became apparent is that there is not enough visible matter to account for the gravitational behavior of large scale objects in the universe.  So astrophysicists developed the concept of “dark” matter to account for what seems to be missing.  It is dark because it doesn’t appear to emit any kind of radiation or show any of the other signs typically associated with matter’s presence.  This article does a good job of explaining the state of dark matter research.   Scientists are pretty sure it exists, but have been stumped on finding a way to directly detect it, as opposed to inferring its presence.  Kind of like you have to see something to know for sure it is there.  It may be that the only way this dark matter interacts with anything else is via gravity, in which case it not only is weird, but essentially undetectable.

Other than the dark matter scenario, the next best, but very unlikely, solution to the apparent discrepancy is that the current understanding of gravity and the equations governing gravity are in error or incomplete.  In any event, the future of the universe is dependent on the answer!!  Literally.  But none of us will be around by then, so kind of irrelevant.  (BT Post)