The Weird Science of Tossing Stones Into a Lake

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.

Comments

On The West Coast...

[__aaclcg7560]

The only way to appreciate the science of tossing stones into a lake is to be stoned yourself.

Jumped the shark

[Anonymous Coward]

Slashdot has officially jumped the shark with this splashing story. Really, who gives a toss?

Make you a deal...

[djupedal]

If you promise not to mess with the nature of my nozzle's highly dynamic collapsing nozzle-structure, I won't mess with yours - unless you want me to, of course, in which case I would expect to be able to count on reciprocity.

I think that's only fair, I mean, especially given that we just met and all. Let's just hope your nozzle hasn't been anywhere unseemly lately. I hate unseemly nozzles and I have no use for any with a rather static collapsing nozzle-structure, as I'm sure most people do. yuck....

Looks like we elected the wrong guy

[Trepidity]

Imagine what the U.S.'s technology leadership could've been like if we had put a President in the White House who truly understood this kind of cutting-edge science.

Re:Looks like we elected the wrong guy

[phantomfive]

Wow, you posted the link to a youtube video and now slashdotters are starting to post over there. Check out this comment for example, made about an hour ago:

Wait, what? Some "people" will spend $15 to $20 for the tickets to sit through 'Butterfly Effect,' 'The Hitchhiker's Guide to the Galaxy' and 'Shrek' but still make themselves known to Big Brother as unclear on such a plain and simple concept as we have in this video? OK, put the cell phone down and step away from the 'candy.'

Notice these signs:

* The implication that all other people are stupider than the poster.
* Talking about geeky movies
* Vastly over-estimating the value of a movie ticket, showing this person never actually goes to the theater, because he has no friends and just downloads all the movies he or she watches.
* Totally out of place comment
* Exaggerated, unexplainable paranoia about big brother.
* Referring to 'drugs' in terms that no one who actually is on drugs uses.

Strangely, somehow even the slashdotters on youtube get more stupid.

Verrry Interesting

[denmarkw00t]

Neat! I want to see what that cone looks like as it develops, in super-slow motion.

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?

Re:Verrry Interesting

[shams42]

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...

How ARXIV and PRL work together

[imsabbel]

Just some pieces of info for people who might not know:

Nowadays, all the major publishers dont have an issue if you post a prepring on arxiv, prl included.
If you want to get a preprint out, the procedure is as follows:

1) You put something on arxiv and submit it to PRL.
2) After a few weeks/months, you get your referee reports.
3) Then you revise it, and update your arxiv version.
4) Paper gets accepted. Paper is entering the editorial process, and you get proofs.
  -> at this point, APS has contributed to the paper. The specific version proofed by PRL can no longer be uploaded to ARXIV /etc.
5) Final corrections, ready to print.

Nowadays, the proof and setting part is relatively minor. Most likely you will have written it in RevTex, and have PDF figures, so its an no issue.
But they still allow you to send them the text in word and the figures in phyical form (ink drawing, whatever), if you are really interested in it not getting published quickly.

So for most issues, a paper on Arxiv might be 99.9% identical to the final published paper, and only diiffer by the editorial issues. But you cannot know it. It might also represent a state from before the peer review.

Re:How ARXIV and PRL work together

[skine]

My impression of the system is:

1) Hey, respectable journal! Here's my paper. You own it now. Please publish it?

2) Journal either publishes it, or doesn't. Either way, they own your paper and pay you nothing.

3) You want to spread the information, so you post it for free on the internet. This is a breach of copyright, but the Journal doesn't really care because the same number of people will buy the magazines regardless.

Re:How ARXIV and PRL work together

[Krahar]

In my experience you only hand over copyright AFTER the paper has been accepted for publication, and you ARE allowed to post preprints on the internet. What you are not allowed to do is to take the final PDF that the paper prints and distribute it, even if it is word-for-word identical other than editorial changes.

Re:How ARXIV and PRL work together

[jschen]

Nowadays, all the major publishers dont have an issue if you post a prepring on arxiv, prl included.

True in some fields, but not all. The two biggest chemistry journals, Angewandte Chemie and Journal of the American Chemical Society, both do not allow submission of communications for which preprints have been released. One also can't submit it elsewhere at the same time. (One can, though, submit a paper to either journal after another journal has already declined to publish it.) As for the major multidisplinary journals, Nature allows publication of preprints. Science does not.

Re:How ARXIV and PRL work together

[Interoperable]

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:How ARXIV and PRL work together

[Interoperable]

I think that's correct. You can generate a pdf of the exact article that the journal has and distribute it freely because you retain the rights to the content. The exact formatting, however, is copyrighted exclusively by the journal so you can't distribute the pdf you get from their website.

PT Barnum

[v1]

It's funny that the APS wants to charge non-subscribers $25 to download what is available for free on the arXiv.

If there's somebody stupid enough to pay for it, there's always somebody smart enough to charge for it.

Economic Darwinism hard at work, parting fools from their money since before 5,000 BC.

Testing Process

[KneelBeforeZod]

I'd love to see the testing process for this.

Tries 1 - 100

1. Plop
2. Plunk
3. Plunk
4. Bloop
5. Plunk ....

Give me a grant!

Viscosity Changes the Sound Too

[Tisha_AH]

My younger brother discovered a key principle of the viscosity of fluids when he was 12 years old. He and his friend decided to drop a gigantic boulder down the center hole of an outhouse, they were standing over the "opening" to see the effect.

I imagine the sound was much "deeper" but their screams were really high.

It was a 2 mile walk to the nearest running water for them, our camping trips were never the same after that.

Re:Viscosity Changes the Sound Too

[mikael]

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.

Re:Who would have thought...

[Garble Snarky]

Full understanding of the phenomenon would allow simulation and rendering of it in computer graphics. That's definitely tech related, and its reason enough for me to take a look at the paper.

You forgot the name of the scientist!

[Hurricane78]

For anyone who cares: Her name was: Amélie Poulain.

___
*Waiting for the about 3 french female geeks who get it* ;)

Re:The two papers aren't identical

[oldhack]

Yep, one costs you 25, the other diddly squat.

See APS Physics viewpoint on the subject for more.

[itdock]

Designed for mere mortals to read, should really have been included by the OP. http://physics.aps.org/viewpoint-for/10.1103/PhysRevLett.104.024501

Re:The two papers aren't identical

[tenco]

One costs you 25$ and was reviewed by peers, the other not.