quote:
Speed of light barrier? First you are making the assumption that the speed of light is a constant - which it is not.
Constant cannot be sped up or slowed down under any condition. For this reason the speed of sound is not constant as it travels faster or slower dependent on the medium through which it travels. Even that air temp. can affect sound speed.
Researchers have been able to slow light to 38 mph
Physicists Slow Speed of Light – Harvard Gazette
I would now submit that the speed of light is not a constant.
Perhaps you are beings confused by the somewhat ambiguous terminology that we use. When we say "speed of light", we are usually being a bit sloppy. What we usually mean is "speed of light in a vacuum," which we designate by the constant
c. And when we speak of the "speed of light" as constant, we
always are referring to
c, the speed of light in a vacuum. The speed of light in a medium (i.e. not in vacuum) is always slower than it is in vacuum.