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U.S. embassy in Havana — Parallax Forums

U.S. embassy in Havana

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:

cuba_embassy.jpg

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

Comments

  • The article says "The incidents occurred in 2016, when 18 of the 21 affected diplomats reported they heard strange sounds in their homes or hotel rooms." That would imply that it did not occur at the Embassy where the poles are.
  • I did see that, but the article did not specify whether those persons were living in or near the embassy building. Even if not, it's possible that sensations experienced at the embassy might have been subconsciously extrapolated to more distant environs.

    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
  • It's happened before, dangerous art.
    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.
  • mikeologistmikeologist Posts: 337
    edited 2018-02-18 07:10
    Also from a physics standpoint it reminds me of the Tesla Valve which employs the friction of differential gas speeds and directions. fig 1
    1329559-1.gif
    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.
  • Phil, your theory appeared in a Scientific American article on February 16 -- https://www.scientificamerican.com/article/ldquo-sonic-weapon-attacks-rdquo-on-u-s-embassy-don-rsquo-t-add-up-mdash-for-anyone/ .

    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."
  • rjo__rjo__ Posts: 2,114
    About 18 years ago I was asked by our side to visit Dr. VV Lednev (RIP). He took me to the Helmholtz Eye Institute in Moscow, where they were using low powered, low frequency magnetic fields to treat traumatic iritis and uveitis... as opposed to using prednisone type medications.

    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.
  • The article says: "Low-frequency infrasound, high-frequency ultrasound and microwaves have all been shown to damage the brain, the researchers noted."
    It's obvious what the next step should be.
  • rjo__rjo__ Posts: 2,114
    I asked what Russia did about unauthorized uses. His answer was that they anyone stepping over that line was shot. They were pretty happy with this solution... it is still a problem in other jurisdictions.
  • rjo__rjo__ Posts: 2,114
    In my experience, it is best to view such incidents as part of a conversation. I wouldn't venture an opinion about this particular episode(although I definitely have one:)...

    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...

  • I'm thinking more in terms of the poles acting passively when the wind blows. I think the State department has ruled out anything more active than that. Purely from a physics standpoint, ignoring all else, could wind blowing through an array of poles like that set up a resonance pattern resulting in an infrasonic standing wave? If you've ever been in a sailboat marina during a windstorm, you might recognize the possibility...

    -Phil
  • rjo__rjo__ Posts: 2,114
    They are sticking up far enough to act as dipoles. The fields required are actually incredibly weak... a resonance pattern would be sufficient. I know what the State Department said... I just don't know why they said it.

    As far as infrasonics go... you have to get it into the building... how would that work?
  • The location of symptom onset isn't conclusive. Most hearing ailments occur after exposure, sometimes days, weeks, or even months after. As one example, tinnitus following exposure to very low frequencies, even at a low dB, is not uncommon. Dizziness and vertigo are typical side effects not of the sound, but of the disruption in the inner ear. Not everyone with tinnitus hears "ringing."

    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.
  • The following history is digged from references I have inside my memory, based on +- 48 year'old (maybe more, I'm not sure) readings I've done, when I was a teenager.

    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
  • Tracy AllenTracy Allen Posts: 6,656
    edited 2018-02-19 19:12
    See
    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.

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