I’ve Moved!
November 20, 2008
So I’m sure that most people have noticed that the site has been offline for a few days. There’s a reason for that, which I will get to shortly. But first, let me just say this:
In fact, I am blogging at a new site I have just finished setting up: kennethhynek.net. A full explanation for the reasons behind the move can be found here
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That said, this is not the end of Time Immortal. My wife Grace has expressed interest in taking over blogging at this domain, and I am working to make sure that she gets set up here as soon as possible.
Also, my profound apologies for the modification to the site face; the move was not as seamless as I would have hoped, and many of the image files for this theme, and in the gallery, were corrupted during the course of their evacuation from my previous web host’s servers. Until such time as I have repaired them, I’ve put a clean-looking template in place of the previous one.
Update: for the purposes of further traffic shaping, new posts from kennethhynek.net will be excerpted below. Full articles can be read at the new blog.
Overturning Copernicus
September 29, 2008
Turns out Earth may just be in a special location after all.
…a paper set to be published in an upcoming edition of Physical Review Letters…by a trio of Oxford astrophysicists suggests a different explanation for the accelerating expansion. In their proposal, dark energy does not exist at all and the supernovae data that led to scientists to propose it was improperly interpreted. In coming to this conclusion, however, the three researchers have to throw out a philosophical principle that has guided astronomy for over 450 years.
…In 1543, Nicholas Copernicus‘ revolutionary tome De revolutionibus orbium coelestium (On the Revolutions of the Celestial Spheres) was first printed. In the book, Copernicus put forth a heliocentric theory that eventually overthrew the Ptolemaic idea that the Earth stood at the center of the universe.
This single book produced modern astronomy and is credited with kick-starting the scientific revolution. In it, Copernicus (among other things) put forth the concept that the Earth is not unique and does not occupy any sort of special position within the solar system. A generalization of this principle — the [E]arth does not occupy a favored position within the universe — has, along with Einstein’s equations, become the founding assumption of modern cosmology.
In the upcoming PRL paper, the authors postulate that we are indeed in a special location within the universe, specifically, “near the centre of a void where the local matter density is low.” This isn’t exactly a small void — it would need to be on the order of the size of the visible universe to get the new model to work. Still, the earth would be near its center, which is a vaguely pre-Copernican notion and, as a side effect, the model does away with dark energy. Unfortunately, it also does away with the notion that we can infer universal properties from local observations.
Now I ask the Reader: what’s so bad about that last bit? Is it not, in a certain sense, arrogant to assume that we can infer all that much about the properties of most of the Universe based on our limited observations of a fraction of a percent of a percent of a percent of a percent of it, and then only that tiny bit that is essentially within the local area of our planet?
This is a most interesting proposal that is being put forth here, and one to watch.
