Slashdot Mirror
Intergalactic Missing Mass Missing Again
Ponca City, We Love You writes "Researchers at the University Of Alabama In Huntsville have discovered that some x-rays thought to come from intergalactic clouds of 'warm' gas are instead probably caused by lightweight electrons — leaving the mass of the universe as much as ten to 20 percent lighter (in terms of its ordinary matter) than previously calculated. In 2002 the same team reported finding large amounts of extra 'soft' (relatively low-energy) x-rays coming from the vast spaces in the middle of galaxy clusters. Their cumulative mass was thought to account for as much as ten percent of the mass and gravity needed to hold together galaxies, galaxy clusters, and perhaps the universe itself. When the team looked at data from a galaxy cluster in the southern sky, however, they found that energy from those additional soft x-rays doesn't look like it should. 'The best, most logical explanation seems to be that a large fraction of the energy comes from electrons smashing into photons instead of from warm atoms and ions, which would have recognizable spectral emission lines,' said Dr. Max Bonamente. The work was published Oct. 20 in the Astrophysical Journal."
He might be a crackpot, but the idea isn't. Google on MOND.
What's easier to believe - that there's a ton of missing mass out there as "Dark Matter" - something that we have no direct evidence for - or that gravity works differently on large scales than a smoothe 1/r^2 at all distances - and works exactly in the way that we observe? Remember that every time that we've had a strong classical theory replaced by something else, it's been at the extremes of our observation - the very fast for special relativity (which reduces to newtonian motion at lower speeds) and the very small for quantum mechanics. We know we're not getting something right on the large scale, and we know that our picture of gravity is incomplete, as we don't have a good quantum gravitational model.
I don't know, honestly - but it's clear that there's something we don't understand and I think that our human-scale intuition is not well suited for figuring out what explanation is more likely, just as QM and SR aren't very intuitive. Right now, we've got competing models but neither is very satisfactory without more data.
"It is our blasphemy which has made us great, and will sustain us, and which the gods secretly admire in us." - Zelazny
...they are a bunch of sharks circling information, just waiting for that first bit of blood that suggests a hole in some established theory.Trying to poke holes in in established theories (also known as conducting experiments and analysing empirical data) is more properly called the scientific method. You make it sound like a bad thing, and that ivory tower guardians of cryptic scrolls are the true scientists. You have it all backwards. Theories shouldn't need propping up, they should stand on their own, and especially stand up to repeated scrutiny and analysis. If we failed to poke holes in established methodology there would be no Newton, no Einstein, no progress to speak of.