Dark Energy is a repulsive force that is the dominant component (69.4 percent) of the universe. The remaining portion consists of ordinary matter and dark matter. Dark Energy, in contrast to both forms of matter, is relatively uniform in time and space and is gravitationally repulsive, not attractive, within the volume it occupies. The nature … Read more
In the early 1990s, one thing was fairly certain about the expansion of the universe. It might have enough energy density to stop its expansion and recollapse, it might have so little energy density that it would never stop expanding, but gravity was certain to slow the expansion as time went on. Granted, the slowing … Read more
Here is an amazing fact: The matter we know of that makes up all stars and galaxies only accounts for 5% of the content of the universe. The rest is called Dark Matter. It does not interact with the electromagnetic force and therefore does not absorb, reflect or emit light, making it extremely hard to … Read more
Why many physicists chose to define the universe in terms of the physical properties of a time or space-time dimension instead of four *spatial* dimensions is puzzling because, as was shown in the earlier article “Defining time” Sept 20, 2007 there is no observational evidence supporting it having physical properties. But even more damaging is … Read more
Is time travel possible? The laws of physics in the microscopic world suggest that it is because the physical processes they define at the subatomic level appear to be either entirely or mostly time symmetric. In other words the theoretical statements that describe them remain true if the direction of time is reversed. However, the … Read more