Hello again! Things have been busy, but this scientist hopes to blog more often. Check out my guest post at Quantum Diaries Survivor. The output of science is definitely not constant.
Another interesting item is in the October 13 issue of NEW SCIENTIST, Supernova Shift May Distort Dark Energy Readings.
"EFFORTS to discover the nature of the mysterious force known as dark energy have been thrown into disarray by the discovery that supernovae are not as predictable as had been assumed.
"Because the average brightness of the stellar explosions known as type Ia supernovae was thought to stay the same over the universe's history, astronomers have treated them as "standard candles". In other words, they have used their apparent brightness as seen from Earth as a yardstick for measuring how far away they are, and from this they have estimated the rate of expansion of the universe.
"Now an investigation of supernovae by Andrew Howell of the University of Toronto, Canada, and colleagues has thrown the basis for such measurements into doubt."
Howell's research shows that the average Type Ia supernova was 12% brighter billions of years ago. Even if DE exists, a "Dark Energy Mission" would not return a single particle or even a track in a bubble chamber to prove it exists. All we would have is an "equation of state" that physicists could puzzle over and write papers about. The equation of state could be explained by changing parameters, like the speed of light. The high precision required for an equation of state requires that supernovae be constant. The Howell paper is in Astrophysical Journal v. 667, p. 37 Do taxpayers really want to spend 1 billion+ US for this?
As someone writes in Quantum Diaries:
"Inferences of cosmic acceleration depend on many other values being constant, including luminosity of supernovae. Many values have changed in the billions of years since distant stars exploded. The metal content of ancient stars is known to have been much less than today. Since we cannot time-travel into the past, it is difficult to determine if fundamental values are constant."
Many quantities that were once thought constant have been found to change. Even the output of science is not constant--it proceeds in fits and starts. Advances are slowed by dogma and accelerated by revolution. We may find that the only constant is change. It is best to give science its opportunity to advance.
This week Space for Commerce hosts the Carnival of Space!