On the previous pages I described some consequences of Einstein's theory of relativity. However, people are
often confused about certain aspects of this theory. The purpose of this page is to address some misunderstandings.
Please remember :
- Systems that undergo acceleration are not inertial systems. They are not equivalent to each other in the sense
of special relativity. They are distinguishable.
- Light has a dual character. It is both an EM wave and particles called photons.
- Nothing can travel faster than light does in a vacuum.
- Massive objects can never reach the speed of light in a vacuum
- In media, due to interaction with matter, the speed of light is not the highest possible speed.
- It is not possible to travel backward in time.
- It is possible to travel forward in time (just wait a little bit).
- Einstein's equations were designed to describe objects moving slower than the speed of light in a vacuum. They
were derived under the assumption that nothing moves faster than the speed of light in a vacuum. Therefore it is
wrong to try to apply them even in HYPOTHETICAL experiments. One cannot say " For a second, let us assume
I move with the speed of light." (If you have an interpreter from English to German, and you speak to him
in German or English, he will produce something meaningful. However, if you talk to him in Chinese, he will produce
either nothing or nonsense.)
- Two speeds in relativity do not add according to the simple classical rule w=v+u; therefore 1+1 is never 2
- The speed of light is the same in EVERY inertial system, no matter how fast an object is moving.
- Simultaneity of events is an observer-dependent notion. Two events that are simultaneous in one frame of reference
(call it A) are not simultaneous in an other frame of reference (call it B) if B is moving with a non-zero speed
with respect to A.
- If you think you designed an experiment disproving Einstein's theory of relativity, you can forget it: it will
not work. Einstein's postulates (and their consequences) are so strongly believed to be true that no one would
try to construct an experiment which would disprove them anymore.
With these few remarks I have finished my discussion of relativistic effects. On the next page, I will
touch a little bit on the connection between light and the quantum world.