Einstein's 1905 constant-speed-of-light postulate has two aspects:

1. Any light moving in a vacuum has the same constant speed, c = 299,792 kilometers per second, as measured by any observer.

2. If the observer were to hurry towards the light source (his speed changes), he would again measure the same constant speed, c = 299,792 kilometers per second.

The first aspect has been disproved - the speed of light travelling in a vacuum is not a constant:

http://phys.org/news/2016-03-optical-slower.html
"Researchers at the University of Ottawa observed that twisted light in a vacuum travels slower than the universal physical constant established as the speed of light by Einstein's theory of relativity. (...) In The Optical Society's journal for high impact research, Optica, the researchers report that twisted light pulses in a vacuum travel up to 0.1 percent slower than the speed of light, which is 299,792,458 meters per second. (...) If it's possible to slow the speed of light by altering its structure, it may also be possible to speed up light. The researchers are now planning to use FROG to measure other types of structured light that their calculations have predicted may travel around 1 femtosecond faster than the speed of light in a vacuum."

http://rt.com/news/225879-light-speed-slow-photons/
"Physicists manage to slow down light inside vacuum (...) ...even now the light is no longer in the mask, it's just the propagating in free space - the speed is still slow. (...) "This finding shows unambiguously that the propagation of light can be slowed below the commonly accepted figure of 299,792,458 metres per second, even when travelling in air or vacuum," co-author Romero explains in the University of Glasgow press release."

http://www.upi.com/Science_News/2015.../1191422035480
"The speed of light is a limit, not a constant - that's what researchers in Glasgow, Scotland, say. A group of them just proved that light can be slowed down, permanently."

http://www.gmanetwork.com/news/story...ut-touching-it
"Although the maximum speed of light is a cosmological constant - made famous by Einstein's Special Theory of Relativity and E=mc^2 - it can, in fact, be slowed down: that's what optics do."

https://www.youtube.com/watch?v=NxJ7_tbbIsg
"Glasgow researchers slow the speed of light"

The second aspect is even easier to disprove - I will do this in my next posting.

Pentcho Valev