The world's oldest profession is lying, the second is cheating. Prostitution is the world's 3rd oldest profession.

Lying and cheating have always been part and parcel of us. In ancient times, kings debased their currency by using lesser gold or silver. The Song dynasty invented paper money that finally failed. The Mongol Yuan borrowed this fiat currency and the Yuan lasted only for about one century only. We now use this cheating fiat system.

On top of paper money, we invented "better" controls - derivatives, risk packaging, zero interest rates, etc. Are these new stuffs meant to eliminate global poverty and to "reduce" the gap between the rich and poor? How is the wealth gap between you and Mr. Gates? Global warming? - I am now wearing a winter jacket!

We suppose physics is free of lying and cheating because we say and believe it is all about experimental "evidence" and strict logic. Logic never fail itself. Yes! But man does not keep good faith with logic;man twists logic - what we call lying.

When Einstein's relativity was first introduced in 1905, many old timers then just rejected it outright; Rutherford (discovered the atomic nucleus) called it a "joke"; Tesla(the greatest electrical genius ever) too refuted it outright. But how come all universities now teach special relativity as a pillar of modern physics? The answer is in the ranking of the oldest profession in the world - the prostitutes are ranked two rungs lower.

Special relativity is based on a second postulate:
The speed of light is a universal constant.
Once the postulate of a theory is proven wrong, out goes the theory ...

The meaning is that the speed of light measured by any observer(experimenter) would come up with the same exact speed 299,792,458 m/s. Whether you are moving towards or away from the light source does not matter. They use the euphemism of "counter-intuitive" to glorify lying - lying now has the best of reputation. It is simple to show the second postulate is trivial lying, but you must be prepared to wean yourself from the "acquired" tasted for things that are "counter-intuitive" that the mass media has fed you in your upbringing.

Now about experimental evidence. We don't always need to do an experiment before we can accept some things as a fact. Say if there are 3 points ABC along a straight line on the ground far apart. At the same moment light signals are sent from A to B and also from B to C. An observer measures the light speed from A to B to be c meter/sec.
Question: What would be the speed of light from B to C?
Answer: the same c meter/sec.

Now the top relativity physics professors of Tsinghua university may insist that the value of c for the speed of light from B to C is only an "assumption"; he would invoke: "anything not verified by an experiment cannot be taken to be a fact in physics". But no! We don't have to verify every single number that appears in a physical situation before we can accept it as a fact. Any person with his head still intact resting on his shoulder would accept the figure c to be a fact. Only the relativity physics professors of Tsinghua university may give a different opinion.

If you drive at 80 km/h and another car is also moving at 80 km/h towards you.
Q: what is the relative speed between the cars.
A: 160 km/h

A fixed light source at A on the ground sends you a light signal and the speed is measured to be c m/s by a stationary person on the ground. You have invented a super vehicle and your speed towards the point A is at ½ the speed of light - 0.5c.
Q: what is the speed of the light signal relative to you (if an experiment could be designed to measure it)
A : 1.5 c or 1½ times the speed of light in empty space, not a universal constant!

But then, the relativity physics professors of Tsinghua university would bring out the Michelson-Morley experiment (MMX) of 1887 to insist the answer is wrong; the MMX experiment is a confirmation the answer 1.5 c cannot be the right answer.

But do we need the MMX experiment to verify if the 1.5c m/s is the true speed if an experiment is really performed? We don't need any experiment. This is because of the common practice of how we measure distance based on a fixed physical ruler; we measure time with a clock;
speed = distance / time.
Even using simple mental arithmetic, we know the ruler is fixed to our super vehicle moving at 0.5 c. We just add 1.0c + 0.5c to give he answer : 1.5 c.

Do we need to do an experiment to confirm the earlier case of the two cars moving at 80 km/h. We don't verify with any experiment; we just add 80+80 =160 km/h. Period.

Things become simple as long as we wean ourselves from the acquired tastes of things counter-intuitive.

Chan Rasjid.