U.S. embassy in Havana
Phil Pilgrim (PhiPi)
Posts: 23,514
I know this isn't a physics forum, but there are a lot of smart physics-savvy people here, so here goes...
For months now, there's been a mystery brewing about why U.S. diplomats have been getting sick from weird sensations experienced at the U.S. Embassy in Cuba. The State Department has all but ruled out deliberate sabotage, after a thorough investigation. Today's New York Times ran a story about the symptoms suffered by our diplomats and the similarities of those symptoms to those resulting from concussions. You can read about it here:
https://www.nytimes.com/2018/02/15/health/cuba-diplomats-attack-concussions.html
What struck me was this photo accompanying the article:
What's with the array of poles in the foreground? I wonder if, when the wind blows, they are able to set up an infrasonic standing wave that could lead to the symptoms reported. Anyway, I've already emailed the State Department to see if this possibility has been investigated.
Please read the entire NYTimes story before commenting, and confine your comments here to physics matters. No politics!!! Otherwise, I'll ask the mods to kill this thread.
Thanks,
-Phil
For months now, there's been a mystery brewing about why U.S. diplomats have been getting sick from weird sensations experienced at the U.S. Embassy in Cuba. The State Department has all but ruled out deliberate sabotage, after a thorough investigation. Today's New York Times ran a story about the symptoms suffered by our diplomats and the similarities of those symptoms to those resulting from concussions. You can read about it here:
https://www.nytimes.com/2018/02/15/health/cuba-diplomats-attack-concussions.html
What struck me was this photo accompanying the article:
What's with the array of poles in the foreground? I wonder if, when the wind blows, they are able to set up an infrasonic standing wave that could lead to the symptoms reported. Anyway, I've already emailed the State Department to see if this possibility has been investigated.
Please read the entire NYTimes story before commenting, and confine your comments here to physics matters. No politics!!! Otherwise, I'll ask the mods to kill this thread.
Thanks,
-Phil
2048 x 1365 - 499K
Comments
Regardless, the main thrust of my question is: could the poles have set up an infrasonic standing wave, given the right wind conditions? That's a pure physics question. If that can be established, then the next question is whether those standing waves might have affected embassy personnel.
-Phil
Remember the Disney Concert Hall in downtown LA? It was built in 2003 the shiny surface reflected far too much light and the curvilinear shapes formed condensing parabolas.
Among the side-effects were blinded drivers and neighboring buildings complained about an abundance of reflected heat.
They ended up scuffing the entire surface to a matte finish and even installed a few new panels to change the shapes where needed.
This reduces the gas flow to less that 10%. It's entirely possible that a lock and pop effect could be experienced there in those poles. This would result in a pressure wave at some frequency that is a fraction or a harmonic of the wind speed.
My 2 cents, hope it sparks something for you.
The article shows a picture of the flagpoles with the caption
"One unproved theory holds that an array of poles and metal awnings in a park adjacent to the U.S. embassy in Havana serves as a system of antennas that are part of a sonic or microwave weapon. Called El Monte de las Banderas (the Mount of Flags), the poles were erected by Cuban authorities to obscure a message board on the embassy that was purportedly conveying objectionable content."
Naturally I wondered what would happen if the power were increased... and of course the answer was that tissue destruction around the eye and in the brain would occur. Although a transducer was used in this case, conversations with American experts later seemed to confirm that such fields could be transmitted by extremely low frequency rf.
When I look at those poles, I wonder if they could induce a standing dipole... which could be used to modify a transmitted signal.
It's obvious what the next step should be.
Let me give you a taste of how these conversations go...
Early on one of our experts conducted an experiment on half dead chicken brains... to which one of their experts conducted the same kind of experiment with more precision using mouse testicles... absolutely hysterical.
Military humor can be even funnier...
-Phil
As far as infrasonics go... you have to get it into the building... how would that work?
Using standard scientific sound measurement tools it should be quite simple to determine if those poles are producing any form of sonic interference. Placing the equipment at various locations over a period of a few months should clear up any mystery.
Being an avid reader since my early days, I always had a trend to fill each and every free moment of my life, reading.
The solely filter I ever use, when selecting what I read, is that the subject must attract my attention, and also add some useful piece of information to my knowledge base.
Please, forgive me for any (or many) inconsistencies you'll find in such ancient samples of my brain's grey mass contents.
The preamble...
Many years after my uncle's father in law suddenly died, his widow sent to him (to my uncle), her husband's full collection of Reader's Digest brazilian editions, since they began to publish them, in portuguese (1942, january), till the last ones she has received.
About thirty years++, twelve editions per year, assembled inside beautifull and eye-attracting hard covers.
To me, they seemed to be a full lot of delicious hamburgers. I simply ate them all.
There was a specific article, whose contents could shade some light about the thread subject.
The history...
When Norad has built its first Colorado underground site, they installed a lot of air circulator fans, to help in the distribution of fresh air inside the complex.
At the time, the fans were constructed using soft metal bushings, not bearings and press-formed metal blades.
Minute imbalances at the fans's blades, a whole lot of fans, in fact, that were placed at the stairways, up and down, did create some kind of low frequency noise or oscillations(stationary wave?), almost inaudible. Almost.
The noise's net effect, apparently, was a series of physical disturbs (diseases?, head aches?), and illness feelings too (perhaps), among many people that worked at the bunker complex (IIRC, women were more affected than men).
After (months) of research, the cause was identified and addressed (new blades?... bushings replaced by bearings??? .. I'm not sure... too old a reference!)
I'm yet to find the originaly referenced article. Googled it, under many querie constructs. No success, yet!
Henrique
Vortex shedding
Kármán vortex street
As applied to 1 pole, it seems to be fairly well understood. A forest of poles though? Amplify? Stimulated emission of vortices?
The principle has been used (but not at all commonly) in anemometry, the vortices being detected via ultrasonics.
Frequency in Hz = (Stroudhal number) * (average air velocity) / (diameter of the strut normal to flow)
-- directly proportional to wind speed.
-- The Stroudhal number applied to the instruments came out at ~0.207 (dimensionless).
-- said to be fairly independent of temperature, pressure and humidity, but that is a bit hard to believe except over an relatively narrow range.
-- threshold of vortex formation is inversely proportional to strut diameter, as is the frequency.
-- The small instrument described generated 2000Hz at a windspeed of 45mph (20mps)
My info is old, "Instrumentation for Physical Environmental Measurement", but the company described, J-Tec, still makes vortex anemometers.
link to report: https://spqr.eecs.umich.edu/papers/YanFuXu-Cuba-CSE-TR-001-18.pdf