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Recipe for Making Symetrical Holes in Water
scottZed writes "Danish researchers found a simple way to make curiously shaped air holes in a bucket of water. Simply rig the bucket to have a spinning plate at the bottom, and depending on the speed, you can get an ellipse, three-sided star, square, pentagon, or hexagon. The effect may help explain such shapes seen in atmospheric disturbances on Earth and other planets. One practical use: really trippy washing machines."
This from a publication with the byline "the best in science journalism"
Bah!
Aliens obviously use the plate to transmit geometrical patterns in an effort to contact us. This proves it beyond all doubt.
But... how will this increase computing speed? Surely some scientist can make something up. Think of the children growing up right now with 3.2ghz dual cores!
I'm curious about the researcher's name, Tomas Bohr, any relation to Niels?
It looks like the end result of system resonance set up between the harmonics and the properties of water. It would be cool to artificially vary the viscosity of the water with polymers, or add salts to increase specific gravity to note the affect on the pattern properties. OK, some of you are thinking, this guy is a nut but it just proves how never ending the learning process is as it relates to even the simplest things observed in nature. I like it.
I say "Triangle"
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
One practical use: really trippy washing machines
practical
adj 1: concerned with actual use or practice; 2: guided by practical experience and observation rather than theory; 3: being actually such in almost every respect; 4: having or put to a practical purpose or use;
This is real advance in physics!
Maybe Computers will never be as intelligent as Humans.
For sure they won't ever become so stupid. [VR-1988]
pedantic
adj 1: Like a pedant, overly concerned with formal rules and trivial points of learning; 2: Being showy of one's knowledge, often in a boring manner; 3: Often used to describe a person who emphasizes their knowledge through the use of vocabulary; 4: Being finicky or picky with language.
A cake with a geometric-shaped bubble in the middle with cream filling. Either Rachael Ray will be all over this, or it will be quick fire challenge on next season's Top Chef. The possibilities are endless.
seriously, what if in the ocean the waterflow is spinning very hard itself under certain conditions, wouldn't that be a possible explanation for the disappearances in the Bermuda Triangle?
Yes, that's right. A suitably airplane-shaped hole would indeed allow an airplane to fall to the bottom of the ocean without getting wet, nicely and logically accounting for its sudden and complete disappearance. Similarly, holes isomorphic to boats and drowning people would account for those inexplicable losses.
Oh, wait, Bermuda triangle---you probably meant a triangular hole. No, sorry, that's just stupid.
But seriously, what if in the ocean the waterflow is spinning very hard itself under certain conditions, wouldn't that be a possible explanation for the disappearances in the Bermuda Triangle?
You don't need an explanation for the disappearances in the Bermuda Triangle, at least no special explanation. The disappearances there occur at no greater frequency per unit of shipping or flight than anywhere else in the world.
SymMetrical.
Anyway, this isn't exactly a groundbreaking discovery.
Not really, no - whirlpools and the like are a whole other kettle of fish than the result presented here. Surface deformations of rotating water and the like have been known about for a long time (and I'm sure have been postulated as an explanation in the past), this is just an interesting little anomoly which turns up under certain particular conditions. Given this is highly dependant on things like the container shape, water depth and so forth, I don't think a direct analog would be observable in the real world.
One practical use: really trippy washing machine
Yes, but only if you run it without any clothes. Very practical indeed!
"You mortals are so obtuse." -Q
This is a simulation, not a competition.
These are scientists at work, they've been doing science stuff for years.
Yes they are, they have rotational and reflective symmetries, they just aren't axially symmetric, which is the odd part, as the system is. Anyone here with a decent knowledge of dynamics?
The article says "At high enough rotation speeds, he says, a fluid will always experience some flow instability that creates a symmetrical structure."
But doesn't the resulting symmetry show that what is achieved is a degree of stability? I've always thought it odd that in so called "chaos" theory, "chaos" is said to result in patterns (fractals) -- but doesn't the fact of a pattern belie "chaos"?
DAILY ROTATION
Frequency of disappearances is not enough to say that a special explanation is not needed. The question was not "Are there more disappearances in the Bermuda Triangle?" but, "Are the circumstances of disappearances in the Bermuda Triangle unusual?" Also, while people keep saying there are statistics, I haven't seen them, nor are sources for the statistics cited. The Wikipedia article doesn't link to any, and a Google search for '"Bermuda Triangle" statistics' turns up no statistics in the first few hits.
When the dutch scientists spun the bucket ever faster, the shapes became even more interesting. It's a pity they were left out of the article. View them here:
http://www.craigslist.org/sby/tls/163096693.html
~those crazy dutch scientists! what will the think of next!
Hey, I know these guys! Way to go!
/.) OTOH, having an advisor from the Bohr family probably doesn't hurt.
This just confirms my suspicion that the chance of a Nature publication is directly proportional to alcohol consumption. (Wonder what it takes to get on
The academic lowdown:
ArXiv preprint
The full B. Sc. project
Now, if only we could make 60gons...
Any sufficiently advanced libertarian utopia is indistinguishable from government.
"We report a novel and spectacular instability of a fluid surface in a rotating system. In a flow driven by rotating the bottom plate of a partially filled, stationary cylindrical container, the shape of the free surface can spontaneously break the axial symmetry and assume the form of a polygon rotating rigidly with a speed different from that of the plate. With water, we have observed polygons with up to 6 corners. It has been known for many years that such flows are prone to symmetry breaking, but apparently the polygonal surface shapes have never been observed. The creation of rotating internal waves in a similar setup was observed for much lower rotation rates, where the free surface remains essentially flat [J. M. Lopez et al., J. Fluid Mech. 502, 99 (2004).]. We speculate that the instability is caused by the strong azimuthal shear due to the stationary walls and that it is triggered by minute wobbling of the rotating plate."
What do you mean, "any more" ?
Forget magic. Any technology distinguishable from divine power is insufficiently advanced.
mmm ... tasty eigenmodes abounding. Congratulations. We study this kind of crap all the time in the Applied Mathematics program at Univ. of Washington. Can't imagine it's so different for other programs.
That being said, I like the nice pictures. I've seen some interesting pictures where a thin layer of fluid is trapped between two cyliders. The inside cylinder is rotated and you can see through the outer one. At certain Reynolds http://en.wikipedia.org/wiki/Reynolds_number numbers you get different forms, such as a stream going helicaly around the cylinders, much like a barbers pole. I think this picture might be in Garrett's "Atmospheric Boundary Layers" book (no, I will not help you find it. That would be cheating and I don't get any of the royalties, so I don't care.).
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887321 = 337*2633
Spelling Nazis 1, Headlines 0.
Q: What did the comedian say to the crowd?
A: If I knew, this joke would be funny.
"Harry Swinney, a specialist in pattern-forming fluid flows at the University of Texas at Austin, says the new observation is roughly in line with what one might expect."
...yeah... the technical term.
Wahhh~? Specialist in pattern-forming fluid flows at University of Texas at Austin? Heck I hope Mr. Swinney's parents didn't flush their saving down the toilet on his college education... oops, I mean, symetrically pattern-forming spiral downward flowing.
"Don't let fools fool you. They are the clever ones."
Ex-NASA genius/nutball (you decide) Richard C. Hoagland has a page full of great pictures illustrating the above:
Hyperdimensional Hurricanes?
Frequency of disappearances is not enough to say that a special explanation is not needed. The question was not "Are there more disappearances in the Bermuda Triangle?" but, "Are the circumstances of disappearances in the Bermuda Triangle unusual?"
It is the same question. If there are no more disapearances there, there is no need for any consideration of unusual circumstances. Unusual circumstances are only needed to explain unusual numbers of disapearances, and there aren't any. Looking for extraordinary explanations of ordinary statistics is unscientific and pointless.
Also, while people keep saying there are statistics, I haven't seen them, nor are sources for the statistics cited.
A good source of statistics is insurance payments for missing vessels: Lloyds of London claim no evidence of any special effect associated with the Bermuda Triangle area (if there were, ships would have to pay extra insurance to enter the area).
Some better photos can be found here, along with a video. Unfortunately the video seems to show the vortex from its side rather than the top. Pretty cool though!
http://dcwww.camp.dtu.dk/~tbohr/RotatingPolygon/
Maybe they check for spelling errors in some <smartass>paralell</smartass> universe...
Program Intellivision!
I have one of those new powerful toilets and been studying this effect closely.
How about Unca Cece? The Straight Dope covered this awhile ago. Cecil references a book called The Bermuda Triangle Mystery--Solved by Lawrence David Kusche.
--JoeProgram Intellivision!
Venturing a guess that the speed that the false bottom is rotating at is related to the velocity that a vibration propagates through water, and the shapes are the result of resonance with the 'corners' nodes, and the edges antinodes.
Thoughts?
I wouldn't consider the mad hatter mad. Just reality impaired. He sure can make a mean cup of tea.
Does this remind anyone of Riven?
Have you tried searching past page three?
sent from my slashdot browser.
So why the different shapes? As the bucket speeds up, three things happen. There's a different speed differential between the bucket and the water, the water depth decreases and the extra g forces increase (effectively increasing local gravity). This changes the wavelength of the wave. So, since the bucket has a finite circumference and is circular, standing waves will form that go back to their own starting point which will make shapes of integer numbers of sides. (non integer numbers of sides will not form a standing wave).
Engineering is the art of compromise.
who moderated this post Funny. Dumb guy doesnt even read the article and shoots off his mouth. Look at the effing pictures and you would know its not a triangle.
OMG I just realized the moderator might be laughing at his stupidity and thats why he/she moderated it Funny. Well its not kind to laugh at rednecks. its not their faults their Moms really loved their Brothers.
**Life is too short to be serious**
This reminds me of the work of the Swiss doctor Hans Jenny in the 60s. Dr. Jenny sent audible simple sine waves through various media and photographed the patterns that would emerge.
The results were often strikingly beautiful and symmetrical. His two books on the subject, full of high-quality imagery, were recently reprinted as one volume. He called his study of wave properties "cymatics."
The photographs illustrate the multi-sensory aspect of all phenomena. Frequency and wavelength show their existence in many forms and media, all representing the same phenomena. You can string a violin bow over sand on glass and see some incredible webs of patterns emerge in the sand. It's amazing to think that both aural and visual feedback from the same source can be produced so simply. And, importantly to myself at least, have both be aesthetically pleasing.
http://www.cymaticsource.com/ has the reprints of the books. I think they also relate it to a lot of more sketchy spiritual stuff that the good Dr. never mentioned AFAIK.
In this case in TFA, the researchers have seen the amazingly symmetrical and simple visual representation of the interaction between fluid, vessel, and frequency (rotation). It does make sense that such a simple phenomenon (rotating fluid) would have a simple, fundamental visual pattern. I bet it looks a lot more interesting than it sounds though.
"The researchers found that once the plate was spinning so fast that the water span out to the sides, creating a hole of air in the middle, the dry patch wasn't circular as might be expected."
If only English were so symmetrical. It's "spun".
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make install -not war
This reminds me of the unexpected patterns of Taylor-Couette instability that develop in the fluid between two rotating co-axial cylinders. Such patterns are similar to the bands on Jupiter.
Now someone go milk the beetles and give me a kortee'nea, I need to write some Ages badly :-) Oh, well, back to Povray it is then... :-P
However, in actuality those people going missing at the second station are actually kidnapped. Of course since five people disappearing is not unusual, you would not care to investigate this at all? Even if many suggested that there may be some foul play involved?
You could easily come up with many more similar scenarios to illustrate my point. Not investigating mysteries, even if just to dispel the myth surrounding them, is what is unscientific.
No, you have it the wrong way around. You are coming up with the myth that they are kidnapped based on no evidence at all, and for no reason.
It would indeed be unscientific to investigate if these people were kidnapped, but it is very disorted logic to come up with the idea from nowhere that kidnapping has happened. You can't start with the principle that there is a mystery!
The problem with your approach is that because it is unlikely that we will be able to find the exact cause of all disappearances, there is always room for myth and mystery. The point of looking at these things rationally is to decide whether such myth and mystery has any place.
So sure, there may be absolutely nothing extraordinary about the Bermuda Triangle and there may be no more disappearances there than anywhere else. If there are unusual circumstances surrounding all or nearly all of those that do take place there though, does that not suggest that there may be something interesting to look at?
It would do if there were any evidence of unusual circumstances. There isn't. There are no more disappearances there than anywhere else, so you could in principle pick anywhere at all and suggest mystery.
They're stoners. whoaaaa....
It's some kinda floating point rounding error, maybe god should switch to doubles.
[i]I hope that this is not the highpoint of his professional career because that would just prove that even science is riddled with nepotism[/i]
er... why, did his grandfather hire him and give him a research grant?
Just then the floating disembodied head of Colonel Sanders started yelling Everything You Know Is Wrong!-Weird Al
Just one drawn on the hyperbolic plane. ;)
No, you first have to kill lots of people, before you can win the Nobel peace prize.
Oh well, what the hell...
I've observed this effect using a "Zero Blaster" fog ring gun. The package indicated that "technique" was required for optimal performance, so I practiced and was eventually able to make super rings that were star-shaped and would travel faster, straighter (for a time), and further than an ordinary circular ring could. They also had other interesting properties...
I watched these super rings transition from their star-shape (usually 4 to 6 points) to an ordinary circular ring once enough energy had been lost to air friction. Upon "decaying" like this, the whole ring experiences severe turbulence - strong enough to eject parts of the ring from the body before it suddenly re-stabilizes as an ordinary circular smoke ring. It also abruptly changes direction (slightly) and continues to travel at a slightly reduced speed. The bucket experiment is quite different because it's externally powered and thus won't decay.
The ring decay phenomenon was very interesting to me and, combined with the star shapes, gave me the first clues about what's going on and I'm now sure of the solution and that it applies to the bucket experiment too. The theory I came up with was that two vortices are working together to create this effect. The primary vortex is, obviously, the toroidal flow of the smoke ring and the axial flow in the bucket. The secondary in both cases wraps around the primary like a candy cane and makes some number of complete turns around it so it meets-up with itself to form a stable closed-loop vortex.
The fact that regular geometry pops out of this should be no mystery then. Consider that the secondary vortex, however initiated, is likely powered & controlled by the primary and is thus bound to it. As it wraps around the primary, it must make a whole and complete number of turns around it or one of its up-flows will meet a down-flow and it negates its own energy, hence the turbulence and ejected fog during the decay process, which is simply when the secondary fails. Thus, you see what is stable and lasts and not those which don't - a conclusion of profound simplicity.
I noted other observational evidence supports the secondary vortex. In my experiments, this fog was heavier than air and because of that, ordinary circular rings begin to sag and eventually "drip" fog after a time. The fog contents of these star-shaped rings is clearly and visibly rotating axially (perpendicular to the primary) while traveling, however without rotating the ring itself (if you can imagine that - just the fog rotates within a non-rotating star-shaped ring) and keeps the ring from sagging - at least until the ring decays to an ordinary circle in the end anyway.
This theory could be perhaps be verified with a bucket experiment, which I will not attempt, by adding colored dye high-up or low-down and in a corner formed by the air gap opened up by the vortex. If there is a secondary vortex present, the dye should move from top to bottom and/or vice-versa quickly - before it reaches the next corner in fact, as each corner of the shape should represent a complete turn of the secondary vortex around the primary. These results would be interesting to know, but not so useful to me hehe.
Could the tri-star shape possibly in atmospheric conditions divide and therefore help explain multiple tornadoes spawning off from each other?
Like a city whose walls are broken down is a man who lacks self-control.
Neat this might give a way to measure viscosity of an atmostphere of a distant planet. On the other hand, might interfere with trying to identify ET constructions. Every regular polygon we find we are going to now start looking at whether there is some rotating fluid involved.
There are some great videos of a similar behavior in a drop of mercury undergoing a cyclic surface reaction. It's a classic, called the "mercury beating heart." The drop will pulse in trianguloid and hexagonoid patterns. "Activity 5" is particularly good.
"But seriously, what if in the ocean the waterflow is spinning very hard itself under certain conditions, wouldn't that be a possible explanation for the disappearances in the Bermuda Triangle?"
Yeah, that would explain it. If I was piloting a DC-9 full of people and saw a huge triangle-shaped hole in the ocean below I'd surely fly down the friggin' hole to see what's at the bottom.
"We have an A-Bomb...what more do you want, mermaids?" --I.I. Rabi, speaking in defense of Robert Oppenheimer
If only English were so symmetrical. It's either "span" or "spun" for the past tense (note, not for the past participle). Span is used less in American English.
=w=
If only the Atlantic were so symmetrical. "Span" is described only as archaic when it's the past tense of spun, and not mentioned anywhere else, not even when listing conjugations of "to spin". Any citation of span as "past spin", so I don't sound archaic even elsewhere than America?
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make install -not war
I think you were wrong. Should I think you wrung?
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make install -not war
pedantic: adj 1: Like a pedant, overly concerned with formal rules and trivial points of learning; 2: Being showy of one's knowledge, often in a boring manner; 3: Often used to describe a person who emphasizes their knowledge through the use of vocabulary; 4: Being finicky or picky with language.
joke: n. 1. Something said or done to evoke laughter or amusement, especially an amusing story with a punch line. 2. A mischievous trick; a prank. 3. An amusing or ludicrous incident or situation.
recursion: n. Mathematics. 1. An expression, such as a polynomial, each term of which is determined by application of a formula to preceding terms. 2. A formula that generates the successive terms of a recursion.
recursion: n. Mathematics. 1. An expression, such as a polynomial, each term of which is determined by application of a formula to preceding terms. 2. A formula that generates the successive terms of a recursion.
This is not my sig.
If you spun the bucket and the rest of the universe around the false bottom instead, would you get the same results? ;-)
-Forrest Cameranesi, Geek of all Trades
"I am Sam. Sam I am. I do not like trolls, flames, or spam."
Well, when I said it was used less in American English I should perhaps have mentioned where it is used strongly: not so much in Britain as in the remnants of the old empire.
Wiktionary lists it as Australian English, and archaic elsewhere. Being a New Zealander I can say it's quite backed by usage here, as well as over the Tasman. Keeping with the less authorative sources, there's a mention in this article of "Australian speakers who use 'span' as the past tense of 'spin'", and this article (from a Malaysian English newspaper) mentions its use.
As far as more prescriptive sources are concerned, I've only got the concise version of the Oxford Dictionary of New Zealand handy which doesn't list most conjugations anyway. I guess I can say pretty confidently, though, that, amongst the 25 million-odd English speakers in Australasia, nobody would bat an eye upon hearing 'span'.
=w=
Comparing buckets of water to the formation and orbit of spacial objects gives new meaning to the phrase, "I live in a giant bucket."
In Soviet Russia, dot slashes YOU!
"When Adam delved and Eve span, who then was a gentleman?" Fr. John Ball, leader in the Peasant's Revolt of 1381
"Is life so dear, or peace so sweet, as to be purchased at the price of chains and slavery?" - Patrick Henry