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This seems kind of stupid. Since BBC World is (mostly, I think) owned by the BBC, they could surely take the advertising revenue hit and let UK viewers access the pages ad-free. A lot of the content on BBC World appears to come from the main BBC anyway - for instance, this bamboo news I heard last week in the 'In Our Time' show on BBC Radio 4 (taxpayer-funded).
I don't know the answer to this, but looking at some LIGO charts (http://www.ligo.caltech.edu/advLIGO/images/refdes03.gif) they seem to be looking at 10-100Hz (roughly). Are there interesting or even expected sources in the frequency band investigated in this paper?
Gravitational waves are emitted at a wide spectrum of frequencies by different astronomical bodies. LIGO's frequency range is limited mostly by seismic activity at the low end and radiation pressure noise (essentially the momentum imparted by photons hitting mirrors) at the high end. It's about as well as we can do on Earth, currently. Indirect detections via astronomical techniques can avoid the issue of seismic activity disrupting measurements, and so it is possible to look at much lower frequencies. These frequencies, however, correspond to different sources to the ones LIGO can potentially see, so we can learn new information about different parts of our universe from both detection techniques.
Where does a gravity wave theoretically come from? All I can imagine is that they would come from a mass increasing or decreasing in magnitude, and I don't know of any way that happens.
The Guardian article refers to a detector which might have made an indirect detection of gravitational waves.
If two massive bodies such as neutron stars or black holes collide, the energy they lose in the form of gravitational energy is propagated away in waves. These waves are ripples in spacetime, and they are quadropolar in nature. This means that they stretch spacetime in one direction while squeezing it in the other.
Gravitational waves form part of the predictions of Einstein's Theory of General Relativity. They are the last piece of the theory yet to receive a direct detection. A notable indirect detection of gravitational waves is the measurements of the orbital decay of the PSR B1913+16 binary pulsar, for which Hulse and Taylor received the Nobel Prize in 1993.
For the purposes of direct detection of these waves, on Earth we've set up a network of laser interferometers (the major players are Advanced LIGO, Advanced Virgo, GEO-HF and KAGRA, though all but GEO are currently in the process of being commissioned). If we arrange our detectors on Earth at right angles, we become optimally sensitive to the majority of gravitational wave sources. If the masses of the bodies involved in the collision are big enough, the ripples in spacetime will be strong enough to change the time in which it takes light to travel along each arm of the interferometer - in one arm the light will take longer time to travel, and in the other it will take shorter time. If we recombine the light in each arm, we can sense via the interference pattern of the light whether a gravitational wave has passed through the detector. In practice there are loads of other signal sources present in the interferometer, and quantifying and eliminating these sources of noise are the major tasks facing these detectors. With these noise sources accounted for, the first direct detection of gravitational waves might be made in the next few years.
The LISA project referred to in the main article is dead since NASA pulled out funding. The project lives on in the form of the ELISA project, funded by European organisations. This has tentative approval for launch in the next 20 years. This mission is not intended to directly detect the 'first' gravitational wave, but rather to detect them in abundence. Indeed, the problem with this type of detector is dealing with the huge number of potential detections. ELISA is also designed to detect waves in a completely different spectrum from the ground detectors, and from different astronomical sources. By the time ELISA launches it is likely that the network of detectors as part of the LIGO Scientific Community will have made the first detection, here on Earth.
It's already a stupid idea to make YouTube negotiate royalties with every national body whether an artist is based there or not. Videos are being blocked from US and UK artists in Germany because the German record industry can't negotiate terms. That's silly.
I know I'm making a lot of suppositions here, but I really have very little sympathy for most record companies and their collective bodies.
Where other games are pretty and complex, OpenTTD is just about micromanaging a massive transport network. It's really consuming. I've lost evenings to the game for years. Sometimes I don't play it for up to a year, then go back to it and lose a month.
Loans for living expenses are also provided on a means-tested basis, and these are paid back by graduates only once they start to earn enough money. If they never earn enough money, they never have to pay their loan back. Also, if they haven't paid their loan back in full by the age of 50 (or something like that) then it is written off. These loans are provided by a semi-governmental organisation which has the power to collect the fees like any bank, so fleeing abroad will work only as well as it would for any kind of loan.
This probably sounds crazy to most Americans, but it works, and it receives overwhelming public support. It seems the only people complaining regularly are the universities who say they make a loss providing the education, but this argument is usually muted when you consider the huge amount of money the government spends on research in these universities (and lecturers are usually also researchers, so you can't really separate the two).