The Weird Science of Tossing Stones Into a Lake 89
Interoperable writes "Researchers in Spain and the Netherlands add another piece to a centuries-old puzzle in physics: the dynamics of an object falling into water. This common occurrence has a complex anatomy that includes a thin 'crown splash' around the perimeter of the impact, a deep cavity of air following the impactor, and a high, narrow jet of water that results from the collapse of the cavity. The new research, recently published in Physical Review Letters, demonstrates that airflow through the neck of the collapsing cavity reaches supersonic speeds despite low relative pressures between the air in the cavity and ambient pressure. Such an effect has no analogue in aerospace engineering or other sciences because of the highly dynamic nature of the collapsing nozzle structure." It's funny that the APS wants to charge non-subscribers $25 to download what is available for free on the arXiv.
$25 (Score:1, Interesting)
It's funny that the APS wants to charge non-subscribers $25 to download what is available for free on the arXiv.
It's not that funny - the version subscribers can download from the APS has, amongst other things, a guarantee that it has had at least one cursory review. While it is true that the arxiv also filters out almost all spam and quite a few of the crackpot submissions, it is still chock-full of total bullshit. Say what you like about APS being the "accepts anyone" whore of the scientific community, the arxiv does not review submissions and probably never well.
Add to this the fact that the vast majority of people reading grabbing papers directly from the APS site will have either individual or institutional membership, thereby paying somewhere between $1 and $0.001 per paper, and you can hopefully see that the APS is not trying to rip people off or make everyone miserable. I imagine they're registered non-profit...
Re:Who would have thought... (Score:1, Interesting)
Re:Verrry Interesting (Score:3, Interesting)
Offtopic: I can't reply to the Racist Facial thread - all the Reply buttons are missing in both Camino and Firefox, and obviously I can post this thread. What gives?
You must not be of Slashdot's preferred race...
Re:How ARXIV and PRL work together (Score:3, Interesting)
No, copyright transfer is very odd for journals. The author retains the right to print the article for personal distribution (you can always find a pdf on the author's website) and distribution of pre-prints is fine. I believe that the journal does hold the copyright, but certain exceptions are included in the transfer paperwork so there's no breach of copyright. Furthermore, images can be usually copied with consent of the author, not the journal (except art supplied by the journal, such as covers).
You can't make a copy of the journal article, but the author can make one for you and send it to you. It's an odd system, but journals are very concerned about their "impact factor," the average number of times that an article in that journal gets cited by other articles. Free distribution of articles helps get citations, which increases the impact factor. Journals just don't want people to freely copy the entire contents of the journal. In any case, they make most of their money by selling site subscriptions to universities.
Re:Viscosity Changes the Sound Too (Score:5, Interesting)
A similar event happened during the construction of the London flood barrier. For some reason, a large amount of material had to be dumped into the river Thames. This might have been cement or just rubble for part of the underground foundations. It was anticipated that this process might generate some sort of pressure wave that would travel at high speed through the water. Thus a warning was given not to be in the river or close any storm drains at this time. Unfortunately, this warning was not received by a particular tenant of an old apartment block which had one end of their combined storm drain/sewer overflow submerged in the river. Minutes after the construction process had begun there was a complaint through the telephone lines that the tenant in question had just stood up in their bathroom, when the toilet had erupted in a geyser that went everywhere.
This was from the same construction company that attempted to fill in a deep hole in the River Thames with liquid cement, only to find that they had filled in someone's basement / underground car park.