Audible Audio, September 2016
It's been fun, over the past few years, reading accounts of recent developments in physics, astronomy, and cosmology. The universe doesn't look the way we thought it did at the start of the 20th century. There are many galaxies, not just one. The universe is expanding. There doesn't appear to be enough matter--enough ordinary matter--to keep the galaxies together, and the rate at which the universe is expanding appears to be accelerating.
The explanations offered for these last two developments are dark matter and dark energy. In this case, "dark" merely means that we do not have the faintest idea what they really are. We can't detect them. They don't seem to interact with ordinary matter at all. Except they hold galaxies together and expand the universe...
It's been fun, over the past few years, reading accounts of recent developments in physics, astronomy, and cosmology. The universe doesn't look the way we thought it did at the start of the 20th century. There are many galaxies, not just one. The universe is expanding. There doesn't appear to be enough matter--enough ordinary matter--to keep the galaxies together, and the rate at which the universe is expanding appears to be accelerating.
The explanations offered for these last two developments are dark matter and dark energy. In this case, "dark" merely means that we do not have the faintest idea what they really are. We can't detect them. They don't seem to interact with ordinary matter at all. Except they hold galaxies together and expand the universe...












