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Robotic Telescope Unravels Cosmic Blast Mystery

An anonymous reader writes "The Register is reporting that scientists from Liverpool John Moores University have used their robotic telescope in the Canary Islands to measure the polarization of light from a Gamma Ray Burst just 203 seconds after its detection by NASA's Swift Gamma Ray Observatory Satellite. The result suggests that the emitting material flowing out from the explosion may not be highly magnetized in the way that some theories had predicted."

5 of 58 comments (clear)

  1. Re:Big Bang? by Anonymous Coward · · Score: 0, Informative

    No. You're an idiot.

  2. Re:Actually, I see a correlation with black-holes. by slew · · Score: 2, Informative

    "I also wondered what might happen to the matter trapped in the accretion disks of two black holes when they began to merge, especially if they had opposing rotation... matter travelling at virtually the speed of light, hitting yet more matter, travelling at virtually the speed of light in the opposite direction... meaning an effective speed of impact almost double the speed of light... and all that happening in an area of dilated time... you have to wonder what that would look like..."

    I haven't done the math, but I'm guessing it wouldn't be as interesting as you might hope.

    The "worst" case seems to me would be the accretion discs would be spinning the same rotation (because if they were spinning the opposite way, the relative velocity of the intersecting parts of the accretion discs would be nearly the same, no?). If they were spinning the same way, and because accretion disc are generally present because of increased viscosity (w/o viscosity, the matter would generally just fall directly into the black hole), the discs would likely just merge and the composite disc would have approximatly double the angular momentum. If some of the theories current are correct, and that the polar jets are ways of bleeding the energy instead of mass to limit angular momentum, then the polar jets would likely more intense, but over two black holes, so the net effect seems like it wouldn't be that different.

    If we when with the opposite, where the rotation was oppossing, the angular momentum seems like it would cancel each other so that there would be less of a reason to need polar jets to bleed energy and although I'm sure there would be lots of crunching, but this would be near the event horizon meaning most of it would just probably "fall-into" one of the black hole's event horizon.

    BTW, just to be nitpicky, when two flash lights are pointed at each other, the photons don't hit each other at twice the speed of light in an area of dilated time (or any other reference frame). In the reference frame of one of the photons (what you are calling dilated time), the other photon is just travelling the speed of light towards it. However, the speed isn't conserved, but of course momentum is conserved within a frame of reference, so that ignoring the relativistic effects for the moment, the resulting momentum of the collision is the momentum of the other object in first object's frame of reference (just like the other object hitting you at near the speed of light, the fact that you are also going near the speed of light isn't gonna make this much different, no?). Now when we put relativistics effects in there, because of conservation of momentu, other object is gonna seem much heavier to the other moving object than to the stationary observer. Did that make any sense?

    Going back, that means the "net" momentum after collision would be pretty much zero for your "worst" case. Big crunch, but now the relative angular momentum is low and all that matter is sitting right near a black hole, might be interesting to them, but would you see it?

  3. Re:Too long of a time delay? by Winter+Lightning · · Score: 2, Informative

    This isn't merely light detection, it's polarimety; 203 seconds is impressively
    fast, since previous attempts have taken several hours. Furthermore, the novel
    polarimeter they built allows instantaneous measurement of polarisation and position
    angle. These objects may be changing quickly so conventional optical polarimety
    won't work.

  4. Re:Actually, I see a correlation with black-holes. by slew · · Score: 2, Informative

    To an observer outside of a black hole, it takes an ever increasing amount of wall-clock time to see something near the event horizon move (things look very still). Of course to the stuff falling into the hole, things sort of happen at "real-time" locally.

    From your observer's perspective you might be thinking that all the collision will be in slo-mo which might be "interesting" or "the-matrix-movie-like", but in real-life you can only see photons, so everything will also be getting dimmer at the same time (red shifted until at the photons being emitted near the event horizon almost have zero frequency as their time gets stretched out and energy approaching zero and thus relatively invisible).

    Short answer is they are having a party, but on the outside we probably don't get to see too much.

  5. Evidence for the Big Bang by Anonymous Coward · · Score: 1, Informative

    "overwhelming nature of the disconfirming evidence for the Big Bang and stellar evolution"

    http://en.wikipedia.org/wiki/Image:Firas_spectrum. jpg