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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."
It shouldn't surprise us that GRB's don't behave as we thought. Nearly everything we think we know about them is based upon assumptions and speculation that are only minimally supported by evidence. There is potential for error at every single step of this process. To continue to be surprised that our telescopes are returning anomalous data when that's what's been happening nearly every single day for years and years and years is silly. At some point, you have to go back to your assumptions and figure out where you went wrong.
"A man cannot begin to learn that which he thinks he already knows." --Epictetus, 1st Century A.D.
With explosions that size, wouldn't 203 seconds of lagtime before observation be a huge killer of the results?
Furthermore, is there any possibility of a dipole radiation distribution for the fraction of linear polarization? Perhaps for this particular sample, we caught the glimpse of a stellar pole? Wouldn't we need a larger sample size to make a more conclusive prediction if this was the case?
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When a black hole forms, the matter trapped within the event horizon has (for all intents and purposes) left our universe. Perhaps GRB's are merely the thermodynamic return on all that lost mass?
You know... I've wondered about that myself in the past...
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...
Maybe someone smarter than me could tell us!
GRBs are thought to emanate only from the poles of a supernova. So no, a GRB can indeed be 'aimed'.
I've often wondered if GRBs aren't simply the result of some technological civilization stumbling onto a new law of physics, and wiping themselves out in the process. It would certainly explain the absence of any voices in a galaxy that -- by now -- ought to be teeming with life.
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The intense bursts of radiation observed from the vicinity of black holes (especially those forming as a result of supernovae) are generally the result of some pretty extreme interactions just before the matter enters the black hole, as this matter is subject to extreme heating and compression and such - enough, even, to perform fusion on some pretty tough stuff and get metals as heavy as uranium.
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It shouldn't surprise us that GRB's don't behave as we thought. Nearly everything we think we know about them is based upon assumptions and speculation that are only minimally supported by evidence. There is potential for error at every single step of this process.
In fact the whole idea is to sometimes find out surprising things that find flaws in the old models and give information to drive the creation of more accurate models. (One definition of information transfer is how much the receiver is surprised. B-) )
That's what we're spending all this money for: To come up with physics that more closely matches the real universe. To do this we have to know what's NOT matching in the old models.
(For those - ideally few of the slashdot participants - who gripe that it's being spent at all: At some point the improved models will almost certainly produce some new and useful technologies and/or end squandering of resources on the pursuit of dead-ends. Of course you can't know up front WHAT technologies it will affect. That's part of what you're finding out.;)
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"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?
I just thought I'd remind you that the original story is about some actual science carried out by real researchers, not a proposed plot for an episode of Star Trek.
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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.