NYTimes, Sci. News, New Sci., Pop. Sci: Of cosmic gamma rays and the lumpiness of reality
A few outlets this week took a flyer into weird physics. Respectable theory has it that, way down near the Planck scale where virtual particles fizz in and out of the universe’s girdle, it may be that spacetime becomes quantized and where, like energy, distance and gravity are in discrete chunks. Electromagnetic waves might then find themselves subtly slowed by the ultimately tiny washboard road. If so, some wavelengths might go a teeny bit slower through the near-vacuum of space. The Tracker is a sucker for these tussles between the shades of Einstein and of the likes of Bohr and Schrödinger. I can’t do the math anymore, but I like the imagery.
In Nature this week a big team of astrophysicists reports that, judging by the essential tie between radiations of drastically different wavelengths from a gamma ray burst or GRB billions of light years away and detected by the Fermi space telescope, the scale of any such graininess to our four dimensional latticework is far smaller than previous upper limits had set. This makes it, as far as the data permit one to say, a null result. If it had come out otherwise a lot more reporters would have needed to brush up on their quantum mechanics metaphors.
Stories:
- Lede prize. At Science News, Ron Cowen reached for the palette of a pointillist for inspiration, starting off with “Georges, smaller dots, please.” As in Georges Seurat, whose paintings on close inspection break into dots rather than smooth brush strokes.
- NY Times – Dennis Overbye: 7.3 Billion Years Later, Einstein’s Theory Prevails ; Fine job of describing why this GRB provided a rigorous, natural experiment to test the theory.
- New Scientist – Rachel Courtland: Universe’s quantum ‘speed bumps’ no obstacle for light ; She expertly explains not only this result, but the reasons an earlier study, that reached a very different conclusion, may have been fooled by its data.
- Popular Science – Jeremy Hsu: Fermi Space Telescope Captures Glimpse of Space Time ; He ties the GRB test of quantized space to the Fermi team’s assembly of a new map of the sky in gamma rays, and also refers to another paper in Nature on the detection of the farthest GRB yet. Good stitching of several results. However, two questions from one sentence: He writes that one measured burst “created enough total energy to rival 9,000 supernova explosions.” The verb ought to be released, not created. The energy was there already, as mass. And the released energy’s total cannot be that high, can it? – but only look that way due to the beaming of the GRB’s blast by happenstance in our direction?
- Symmetry Magazine – David Harris : Gamma-ray burst restricts ways to beat Einstein’s relativity ; A trade pub from SLAC and Fermilab – could as easily go in Grist. It points out that this paper has been out (see Grist) for awhile at the arXiv physics prepublication site.
Grist for the Mill: Stanford U. Press Release ; prepub of paper at arXiv .
Pic: Credit to Aurore Simonnet, Sonoma State University.
Other Fermi Telescope News:
- Sky and Telescope – Ivan Semeniuk: Is Fermi Seeing Dark Matter? ; A prepublication paper at arXiv reports a strange haze near the galactic core – possibly the result of dark matter annihilation, some say.
- Charlie Petit
