My summary. New class of theories with lots of tunable parameters can explain existing observation through choosing the right parameters to tune.
The idea is worth exploring, but don't expect it to overturn the existing orthodoxy overnight. Particularly given that we don't actually have a physical model for how parameters can be tuned, and previous attempts to find evidence of variation in fundamental physical parameters over time have so far failed to find such variation. (See http://thefutureofthings.com/news/1254/proton-electron-mass-... for an example.)
The class of theories is hardly even new. Dirac suggested the possibility of variation in universal constants in the 30s. In the 80s and 90s, at least three different instantiations of VSL popped up and have been getting varying amounts of press ever since.
From John Barrow:
"[An] important lesson we learn from the way that pure numbers like α define the world is what it really means for worlds to be different. The pure number we call the fine structure constant and denote by α is a combination of the electron charge, e, the speed of light, c, and Planck's constant, h. At first we might be tempted to think that a world in which the speed of light was slower would be a different world. But this would be a mistake. If c, h, and e were all changed so that the values they have in metric (or any other) units were different when we looked them up in our tables of physical constants, but the value of α remained the same, this new world would be observationally indistinguishable from our world. The only thing that counts in the definition of worlds are the values of the dimensionless constants of Nature. If all masses were doubled in value [including the Planck mass mP] you cannot tell because all the pure numbers defined by the ratios of any pair of masses are unchanged."
Quick plug: Probably the most public proponent of VSL is João Magueijo who wrote a really interesting book on the process of challenging the scientific orthodoxy, called "Faster Than the Speed of Light." It's an interesting (and often scathing) view of the process of academic science.
Comments
My summary. New class of theories with lots of tunable parameters can explain existing observation through choosing the right parameters to tune.
The idea is worth exploring, but don't expect it to overturn the existing orthodoxy overnight. Particularly given that we don't actually have a physical model for how parameters can be tuned, and previous attempts to find evidence of variation in fundamental physical parameters over time have so far failed to find such variation. (See http://thefutureofthings.com/news/1254/proton-electron-mass-... for an example.)
The class of theories is hardly even new. Dirac suggested the possibility of variation in universal constants in the 30s. In the 80s and 90s, at least three different instantiations of VSL popped up and have been getting varying amounts of press ever since.
From John Barrow:
"[An] important lesson we learn from the way that pure numbers like α define the world is what it really means for worlds to be different. The pure number we call the fine structure constant and denote by α is a combination of the electron charge, e, the speed of light, c, and Planck's constant, h. At first we might be tempted to think that a world in which the speed of light was slower would be a different world. But this would be a mistake. If c, h, and e were all changed so that the values they have in metric (or any other) units were different when we looked them up in our tables of physical constants, but the value of α remained the same, this new world would be observationally indistinguishable from our world. The only thing that counts in the definition of worlds are the values of the dimensionless constants of Nature. If all masses were doubled in value [including the Planck mass mP] you cannot tell because all the pure numbers defined by the ratios of any pair of masses are unchanged."
Quick plug: Probably the most public proponent of VSL is João Magueijo who wrote a really interesting book on the process of challenging the scientific orthodoxy, called "Faster Than the Speed of Light." It's an interesting (and often scathing) view of the process of academic science.