all,

surely issues such as the veracity of fundamental laws and theories in 
physics can only be discussed by physicists. i would not argue over 
technical points in another subject unless i had a firm grounding in all the 
relevant facts and theories and methods.

secondly, for the purposes of a discussion group such as this, we need only 
be concerned with the impact of the areas of sciences (or any other subject) 
which are affecting the crises we talk about. we need to be practical. if 
discussing an area of subject that is well-described, and this theory can be 
empirically tested again and again without failure, then don't we need to 
use it?

going back to the speed of light issue:

Finally, we come to the conclusion that the speed of light is not only 
observed to be constant; in the light of well tested theories of physics, it 
does not even make any sense to say that it varies.

http://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/speed_of_light.html

easy to find something on the internet which contradicts the argument.

but read further:
http://www.newscientist.com/article/dn6092.html

The speed of light, one of the most sacrosanct of the universal physical 
constants, may have been lower as recently as two billion years ago - and 
not in some far corner of the universe, but right here on Earth.

so yes, astronomers have started a debate on long term temporal stability of 
the speed of light, with the term alpha, depending on c, changing by several 
  parts in 10*15. no change found in the last 2 billion years. however, 
talking about the speed of light's constancy is a tricky business. you need 
to consider medium (and changes within that medium over time), the frame of 
reference (is it an accelerating frame), and is it absolute constancy, or 
relative constancy? everytime you put light through glass or water or 
anything with a different refractive index, you are changing its speed.

and so the debate goes on. theories are often challenged. sometimes they are 
changed as a result, sometime they are not, the asserstions of the 
challenger are debunked. but the rest of the empirical physics still occurs, 
we can see and test that. it is a subject that is about creating best-fit 
theories to allow us to understand and predict the world around us to the 
best of our abilities. challenging einstein's theory of relativity will not 
change our understanding at a practical level of the the physics of thermal 
transfer, convection currents and solar energy transfer and greenhouse 
effect modelling. and this is my point. we have tools that work currently, 
some better than others. but these are what we need to be concentrating on.  
the most urgently needed ones.

physics, philosophically is often in crisis. and probably will continue to 
be, as it is a subject that tries to understand the fundementals of a 
universe. but it will be contested by other physicists.

so this is a crisis-forum, but i thought we would be discussing clear and 
present dangers, crises that impact upon all facets of our lives. whether c 
is constant or not does not change our lives presently, just our 
understanding. water shortages, overpopulation, climate change, peakoil, 
wars, plagues, extreme weather, energy shortages - these are the crises that 
are affecting us now, or will be soon. should be we discussing these and in 
more detail?

best,

Jonathan