What’s ‘stoking’ cosmology controversies?
While my brain’s been buzzing over trying to choose a particular controversy in cosmology to concentrate on (e.g. dark matter debate, dark energy debate, dark flow debate, fine-tuning debate, debate over Lambda-CDM model fits…?), I thought it would be worth briefly mentioning something that appears to be fairly uniform among all of them, and indeed in astronomy-related controversies in general.
As with astronomy, cosmology is largely observationally based rather than experimentally based, contrary to most other sciences. Hence, observations can be open to interpretation, which can be based on assumptions made from experiments on Earth; for example, we generally have to assume that the laws of physics tested on Earth apply to the rest of the Universe. Without the ability to manipulate the subject to explore the case further—being able only to rely on further observations—controversies can arise over which interpretation is the correct one or over the validity of the interpretation.
So, controversies surround anomalous observations; observations that don’t quite fit with the current theory/paradigm. Say, missing matter (leading to the dark matter idea) or observed matter (dark or luminous) only adding to about a third of the ‘critical density’, the density required for the Universe to be spatially flat (leading to the dark energy idea). But controversies also surround the interpretation of observations (e.g. why does the Universe have to be at critical density? * Is dark energy the best interpretation of the expansion acceleration data?). This feature of cosmology as a science makes it particularly prone to controversy.
Readings helping this thinking along:
Leggett, A. J. (1987) The Problems of Physics. Oxford University Press Inc., New York.
Liddle, A. R. (2002) The Big Bang: status and prospects. European Review, Vol. 10, 221-236.
* WMAP (Wilkinson Microwave Anisotropy Probe) results now give the curvature of the Universe to be pretty dang flat, but I ask this question as it may have been asked in the early 90s.
Filed under: Anti-BB - observations, Cosmology as a science, Dark Energy, Dark Matter, Observation | Leave a Comment