30 August 2006

Dim view of Dark Matter

colliding clusters

This article on recent Dark Matter reports takes a somewhat, well, dimmer view of the situation than was first published:

“Direct” means “having no intervening conditions or agencies” — implying that dark matter has been observed. But it hasn’t. The pretty image above gives the impression that dark matter radiates blue light. It doesn’t. The mass of dark matter that astronomers “find” is fabricated from assumptions and calculations. The telescope images have had an artefact superimposed — a blue “lensing map” that paints in what NASA scientists believe should be there. They’ve done this before: They painted hot lava fountains onto images of Io where the camera pixels were inexplicably overexposed by intense light. Digitally superimposing some imagined thing or mathematical virtual reality over an image is an artistic activity. It isn’t science. Positing unobserved matter to account for physical phenomena is tantamount to a belief in fairies. If a theorist is unable to discover real objects, which cause the observed effects, it is unscientific — indeed, it is fraudulent science — to invent unreal objects and present them as a “factual” discovery of the cause of those effects.

The article has much interesting discussion of Halton Arp’s studies of redshifts, in which he shows many observations that contradict a simple Doppler interpretation of them quite thoroughly, including in this (the Bullet Cluster) formation.

In fact, quite a handful of Australian scientists are mentioned in & around the article.

Here’s a concluding chunk of commentary text:

Even the “hot gas” is not required: The x-rays are synchrotron (non-thermal) radiation, produced by fast electrons spiraling in the strong magnetic field of the jet.
Instead of colliding, the cluster is forming, exhibiting expected features of such clusters: x-ray jets, arcs, and filaments; a profusion of irregular and disturbed small galaxies; discrepant redshifts.
The Bullet Cluster is therefore much closer than astronomers calculate from the erroneous redshift/distance equation. That means the X-ray energy emitted is far less than calculated and it is not unusual. The cluster is not “the most energetic event known in the universe” but a minor ejection event in nearby galactic space.

So... it seems that some people got a tad too excited about exotica which weren’t — but on the other hand, observations which contradict the exotica would also plough up a lot of other accepted understanding, so they’re ignored for social and political reasons, not scientific ones.

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