I'm surprised no one has mentioned it yet, but there's a simple reason to cheer for success in this lawsuit: it allows people to reject junk channels by opting not to pay for them. The ultimate power of consumers is totally denied to us under the cable providers' current bundling arrangements. As others have said, cable companies are regional monopolies, so it's not like we can go to a different provider in order to express our preferences. Consumers are left with not much of a voice.
Every month I mourn that a big fraction of my bill goes toward perpetuating schlock TV channels that I despise--channels where the content ranges from inane to downright offensive. Why not let me spurn the drivel properly? I want to reward the channels who are sending me the good stuff, as I already do for PBS. It would be nice to be able to support other, non-local cable channels that I admire... and as a bonus, not only would I personally erode the profits of the schlock purveyors, I wouldn't have to worry about my kids rotting their brains on it, because I could keep it out of my house entirely.
But I'm not sure it's such a good idea to take the a la carte idea one step further and do away with channels entirely. Probably we've all had the experience of watching a good show serendipitously, just because it happened to be on. Programming is a service, too. Must we add this to the ever-growing list of things we have to do for ourselves? Sometimes I don't want to program the evening's entertainment; I'd rather let someone else choose it for me (with an option to time-shift it if I like).
During ICF, each fusion reaction has a duration short enough that it isn't necessary to hold the plasma back against the forces of gravity. Er, not quite. A fusion plasma must be confined against its own internal pressure, which for ICF is driven sky-high by compression, shock heating, etc., as well as the energy released by fusion reactions. The idea of ICF is simply to get a decent fraction of the target to fuse before the whole thing blows itself apart. In other words, the plasma can be in effect held together—temporarily—by its own inertia.
Earth's gravity matters not one whit. There is, however, an effective local gravity that is created across the surface of the pellet by the inward acceleration. This makes "out" look like "down", and it can drive Rayleigh-Taylor (buoyancy-type) instabilities. So in that sense, there is a race against "gravity", because the target compression rate must beat the rate of growth of the instability. But that's a whole 'nother story.
While I'm happy to see a/. posting on space weather, the linked article at space.com is more of an exercise in the perils of science writing than anything else. So don't stop the presses, don't phone your mom...
What makes science writing tough is that normal-sounding words have precise meanings to those who are familiar with a field. These precise meanings aren't conveyed by normal-sounding synonyms. The first clue that this article has more enthusiasm than technical accuracy is the phrase "magnetic charge". Ain't no such thing. "Magnetic polarity" is better. "Magnetic fields that are aligned or anti-aligned with the Earth's dipole field" is better still, for the purposes of the article.
Similarly, the article talks about the "merging" of magnetic fields, which is fine. But "reconnection" is the term routinely used by space-science types. It conveys the extra meaning that terrestrial magnetic field lines change topology when they interact with the solar wind: from dipole-like (both ends connected to Earth) to solar-wind-like ("open", or closed at very large distances). Such field lines reconnect again in the magnetotail, on the far side from the Sun.
And what's all this about "the solar wind's electric field?" The solar wind's conductivity is far too high to support any appreciable electric field (in a co-moving frame). Rather, the observed near-Earth currents are generated via a dynamo process, which occurs as the solar wind plasma moves across and through the Earth's dipole-like magnetic field.
The article makes it sound as though the Earth's dipole field changes as much as the solar wind. This is just plain wrong. The only variations of the Earth's field that matter much are the daily spin of the dipole around the Earth's rotational axis, and its yearly trip around the Sun. In intrinsic strength, Earth's magnetic field changes slowly over centuries. By contrast, the solar wind plasma can jump in speed, density, and and magnetic field intensity by an order of magnitude or more, over a time scale measured in minutes. Gusts in the solar wind can and do displace the boundary between Earth-dominated space and solar-wind-dominated space, sometimes by a large margin, but such movement is not caused by anything the Earth is doing.
Finally, the article commits the cardinal sin of omitting any reference or link to a publication to get the full story. My guess is that if one were able to look up such a reference, it would turn out that the authors have simply cooked up some new empirical formula to guesstimate the reconnection rate from various input parameters. If so, this would be a useful advance to space physics, but it wouldn't represent a revolution in our understanding, as suggested by the sensational headline. This shows another peril of science writing: if a writer isn't a quick study, or lacks sufficient background, it's hard for that person to make a proper assessment of the importance of the work being covered.
Still... I'd rather see spotty coverage than no coverage. Just wanted to set the record straight on things that I found misleading in the article.
Slashdot Mirror
This is an off-the-wall solution. (By definition.)
No... ex post facto Law shall be passed.
I'm surprised no one has mentioned it yet, but there's a simple reason to cheer for success in this lawsuit: it allows people to reject junk channels by opting not to pay for them. The ultimate power of consumers is totally denied to us under the cable providers' current bundling arrangements. As others have said, cable companies are regional monopolies, so it's not like we can go to a different provider in order to express our preferences. Consumers are left with not much of a voice.
Every month I mourn that a big fraction of my bill goes toward perpetuating schlock TV channels that I despise--channels where the content ranges from inane to downright offensive. Why not let me spurn the drivel properly? I want to reward the channels who are sending me the good stuff, as I already do for PBS. It would be nice to be able to support other, non-local cable channels that I admire... and as a bonus, not only would I personally erode the profits of the schlock purveyors, I wouldn't have to worry about my kids rotting their brains on it, because I could keep it out of my house entirely.
But I'm not sure it's such a good idea to take the a la carte idea one step further and do away with channels entirely. Probably we've all had the experience of watching a good show serendipitously, just because it happened to be on. Programming is a service, too. Must we add this to the ever-growing list of things we have to do for ourselves? Sometimes I don't want to program the evening's entertainment; I'd rather let someone else choose it for me (with an option to time-shift it if I like).
Earth's gravity matters not one whit. There is, however, an effective local gravity that is created across the surface of the pellet by the inward acceleration. This makes "out" look like "down", and it can drive Rayleigh-Taylor (buoyancy-type) instabilities. So in that sense, there is a race against "gravity", because the target compression rate must beat the rate of growth of the instability. But that's a whole 'nother story.
While I'm happy to see a /. posting on space weather, the linked article at space.com is more of an exercise in the perils of science writing than anything else. So don't stop the presses, don't phone your mom...
What makes science writing tough is that normal-sounding words have precise meanings to those who are familiar with a field. These precise meanings aren't conveyed by normal-sounding synonyms. The first clue that this article has more enthusiasm than technical accuracy is the phrase "magnetic charge". Ain't no such thing. "Magnetic polarity" is better. "Magnetic fields that are aligned or anti-aligned with the Earth's dipole field" is better still, for the purposes of the article.
Similarly, the article talks about the "merging" of magnetic fields, which is fine. But "reconnection" is the term routinely used by space-science types. It conveys the extra meaning that terrestrial magnetic field lines change topology when they interact with the solar wind: from dipole-like (both ends connected to Earth) to solar-wind-like ("open", or closed at very large distances). Such field lines reconnect again in the magnetotail, on the far side from the Sun.
And what's all this about "the solar wind's electric field?" The solar wind's conductivity is far too high to support any appreciable electric field (in a co-moving frame). Rather, the observed near-Earth currents are generated via a dynamo process, which occurs as the solar wind plasma moves across and through the Earth's dipole-like magnetic field.
The article makes it sound as though the Earth's dipole field changes as much as the solar wind. This is just plain wrong. The only variations of the Earth's field that matter much are the daily spin of the dipole around the Earth's rotational axis, and its yearly trip around the Sun. In intrinsic strength, Earth's magnetic field changes slowly over centuries. By contrast, the solar wind plasma can jump in speed, density, and and magnetic field intensity by an order of magnitude or more, over a time scale measured in minutes. Gusts in the solar wind can and do displace the boundary between Earth-dominated space and solar-wind-dominated space, sometimes by a large margin, but such movement is not caused by anything the Earth is doing.
Finally, the article commits the cardinal sin of omitting any reference or link to a publication to get the full story. My guess is that if one were able to look up such a reference, it would turn out that the authors have simply cooked up some new empirical formula to guesstimate the reconnection rate from various input parameters. If so, this would be a useful advance to space physics, but it wouldn't represent a revolution in our understanding, as suggested by the sensational headline. This shows another peril of science writing: if a writer isn't a quick study, or lacks sufficient background, it's hard for that person to make a proper assessment of the importance of the work being covered.
Still... I'd rather see spotty coverage than no coverage. Just wanted to set the record straight on things that I found misleading in the article.