_______ __ _______
| | |.---.-..----.| |--..-----..----. | | |.-----..--.--.--..-----.
| || _ || __|| < | -__|| _| | || -__|| | | ||__ --|
|___|___||___._||____||__|__||_____||__| |__|____||_____||________||_____|
on Gopher (inofficial)
URI Visit Hacker News on the Web
COMMENT PAGE FOR:
URI Invisible Electrostatic Wall at 3M plant (1996)
pontifier wrote 10 hours 2 min ago:
I always felt that this "wall" must have been composed of charged gas
ions in a potential well. This would make it sort of a capacitor, and
would explain why no large sparks or discharge were happening, even
when the voltages involved must have been extremely high.
Kevin-Xi wrote 10 hours 22 min ago:
The part about "throwing bolts" reminds me of the plot in Roadside
Picnic.
stuff4ben wrote 10 hours 59 min ago:
Dang, where's MythBusters when you need them (RIP Grant Imahara)
UncleSlacky wrote 17 hours 16 min ago:
Falcon Space have been attempting to replicate it recently:
URI [1]: https://www.youtube.com/watch?v=KSsX74X_BmA
raydiak wrote 20 hours 33 min ago:
Silly physicists spent generations trying to confine plasma with
magnets and lasers when all along we could have just used plastic wrap.
KennyBlanken wrote 1 day ago:
Yet another request that HN reject any URL that isn't https.
Anyone clicking on a link like this is open to traffic injection. With
several free automated cert services available, there's no excuse for
this other than gross incompetence or laziness.
QuadmasterXLII wrote 1 day ago:
Electric fields really like to be linear, but the described anomalous
effects are highly nonlinear
The non-anomalous effects, like high electric field readings, could
linear
The wall only effects living things- birds, bugs and people
My guess is that the wall is mediated by the nervous system and muscle
contractions, which unlike electrostatic forces, are free to have
thresholds, nonlinearities, and psychological effects. Basically,
everyone involved was getting zapped all to heck and any subjective
experience is plausible downstream of taking a megavolt to the spine
rep_lodsb wrote 1 day ago:
If that were the case, wouldn't people just fall down, and possibly
die from their heart stopping? Instead of feeling an invisible wall
that they can walk away from.
1-6 wrote 1 day ago:
Time for a YouTube video to be made
sans_souse wrote 1 day ago:
There's a lot of interesting ideas in the experiments section, here:
URI [1]: http://amasci.com/freenrg/iontest.html
st-keller wrote 1 day ago:
Wow - nice to know that this old story has survived for so long! I
remember reading it a long time ago. Has this phemomenon been repicated
by someone or has someone invented something because of that?
ericye16 wrote 1 day ago:
It's been a while since I took electrostatics, but I don't understand
the theory behind this. If the rolls become charged and you are
presumably neutral, wouldn't they attract you rather than repel you?
That's what makes me think this story is apocryphal.
hinkley wrote 1 day ago:
All that static discharge is coming at the expense of the mechanical
energy in the system is it not? Iâm surprised they let it zap like
that video and donât try to recuperate it somewhere.
One of the weirdest power scavenging solutions I ever saw used a spark
gap and a bespoke transformer to make a reverse Tesla coil - taking the
very high, very brief voltage spike of a static discharge and stepping
it down to create low voltage over a a longer interval. They attached
it to their shoe.
littlestymaar wrote 1 day ago:
> All that static discharge is coming at the expense of the
mechanical energy in the system is it not? Iâm surprised they let
it zap like that video and donât try to recuperate it somewhere.
Yes, but while the voltage is very high, the energy stored is very
low so I don't think it makes any sense to try recover it (there's
probably much more energy being wasted by poor insulation of the
heated offices or stuff like this).
hinkley wrote 1 day ago:
I was thinking less of energy efficiency and more of containment.
Possibly damage reduction.
littlestymaar wrote 18 hours 8 min ago:
Should the damage become a problem, they'd likely do it, but not
until the damage proves more costly than the cost of preventing
it.
anotherevan wrote 1 day ago:
âSo thatâs what an invisible barrier looks like.â
swayvil wrote 1 day ago:
We can turn beans into peas.
cmpalmer52 wrote 1 day ago:
Reminds me of the time I turned myself into a Van de Graff generator at
work.
I was a theater projectionist, back when you had 20 minute reels you
had to constantly change, while babysitting two high-voltage,
water-cooled, carbon arc projectors. Sometimes the film would break and
youâd have to splice it. So when the theater got a print in, you had
to count and log the number of splices for each reel, then the next
theater would do the same and retire the print when it got too spliced
up (plus, sometimes if it was the last night of a run, some lazy
projectionists would splice it in place with masking tape and then
youâd have to fix it). Sometimes you had to splice in new trailers or
remove inappropriate ones as well.
Anyway, you counted splices by rapidly winding through the reel with a
benchtop motor with a speed control belted to a takeup reel while the
source spun freely. Then, while letting the film slide between your
fingers, counting each âbumpâ you felt as it wound through. I was
told to ground myself by touching the metal switch plate of the speed
control knob with my other hand. One night I forgot and let go until my
hair started rising. Iâd gone through most of the reel at a very high
speed and acquired its charge.
I reached for the switch plate and shot an 8-10â arcing discharge
between the plate and my fingers.
Lesson learned, I held the switch plate from then on.
sandworm101 wrote 13 hours 38 min ago:
I lived in an area with extremely dry winters (dew points below -40).
My bedroom was carpeted. Some mornings I would reach for the light
switch and see a 2" bolt of white pain jump off my finger. It was
like a strobe light. I learned to touch light switches with my elbow.
Same bolt but less painful to take it on the elbow.
ponty_rick wrote 9 hours 26 min ago:
I learned to touch things with a metal object like a key, so the
charge spreads out across the part of skin holding the object and
the pain is less.
dghughes wrote 17 hours 6 min ago:
I worked in a casino that had a wool carpet. When the carpet was new
it was ridiculous the amount of static that it generated on you. I
was wearing steel toe non slip and anti shock shoes too!
I quickly learned to hold my machine keys ring (3 inch wide ring) and
tap it to the slot machine frame. Often a three inch violet spark
would jump and I could even feel my clothes move. One time I even
causing one of the slot machine player tracking system to reboot, it
was that or me better it got the hit.
A manager said at a casino they used to work at they would spray
fabric softener on the rugs to alleviate static. I don't know if it
worked or not.
zombot wrote 19 hours 54 min ago:
Van de Graaff
URI [1]: https://en.wikipedia.org/wiki/Van_de_Graaff_generator
julian_t wrote 12 hours 17 min ago:
The Daresbury Laboratory in the UK had a giant Van de Graaff
generator housed in a high concrete tower. I remember staying on
site and waking up in the middle of the night with a really creepy
feeling that turned out to be caused by that thing operating.
rjsw wrote 9 hours 0 min ago:
The tower is empty now, there is a good view from the top floor
though.
wumms wrote 1 day ago:
Did you finish your shift that night? (Some 2cm arc from an electric
fence brought me to my knees one time.)
madaxe_again wrote 22 hours 0 min ago:
It also matters where the arc lands. I leant over an electric fence
(whim I thought was off) wearing wet swimming shorts to fetch a
ball, once.
Never, ever again.
HappMacDonald wrote 1 day ago:
@idiotsecant is correct. Length of arc correlates to voltage, while
most of the potential pain or damage from an arc will correlate
more to amperage and/or to duration.
HPsquared wrote 17 hours 21 min ago:
So it's not the Amps that get you, but the Coulombs? Or is it the
Joules?
tuetuopay wrote 15 hours 5 min ago:
neither. even a shortcut saying like "total energy delivered"
is not accurate, because it depends on how it is delivered and
how it dissipates.
styropyro made a fascinating (if terrifying) video about it
HPsquared wrote 9 hours 58 min ago:
Sounds a bit like fuse wire (except the frequency
dependence)... There's both a current and a time component.
High overloads can be tolerated for a very short time without
blowing the fuse, while low overloads can be sustained for
longer before the fuse reaches its maximum temperature and
breaks.
myrmidon wrote 15 hours 17 min ago:
Lethality of electricity is multi-dimensional, trying to reduce
it to a single quantity does not really work (exposure time and
electrical frequency are very important).
kadoban wrote 20 hours 24 min ago:
You're correct, but just for fun's sake:
The amperage of static elecricity discharges like this can be
quite high, tens of amps is common.
So walking across a carpet and getting a shock can easily be tens
of amps at thousands of volts, and we're just totally fine
(because it's for a tiny fraction of a second).
idiotsecant wrote 1 day ago:
You had less voltage, but whole lots more current than parent post.
flerchin wrote 1 day ago:
Van de graaff generators discharge with painful shocks. I would expect
something like described in the article to kill someone.
VikingCoder wrote 1 day ago:
[1] "The article says that because of the insulating nature of the
floor and and footwear, no discharges occurred."
URI [1]: https://skeptics.stackexchange.com/questions/53985/was-an-in...
BenjiWiebe wrote 1 day ago:
In that case, the person would've been very quickly equalized to
the same charge, and the wall would be gone (for you at least) more
quickly than you could even feel it.
more_corn wrote 1 day ago:
Reminder to everyone to divest of your 3M stock. They lied about the
dangers of PFAs for decades. Suppressing science to create the biggest
mass poisoning in human history needs some pushback from reasonable
people.
rich_sasha wrote 1 day ago:
Why would an electrostatic force repel humans? We are neutrally
charged.
And if anything, in metals I think (???) you can get attraction as free
electrons in the neutral body are attracted/repelled towards the charge
and the neutral body becomes a dipol (so eg. if the charged body is
positively charged then the negatively charged electrons are attracted
towards it, and vice versa). But that's weak and acts the wrong way.
danparsonson wrote 1 day ago:
It's possible to induce charge in things - this principle is used for
holding silicon wafers inside lithography machines but works for
other materials too ( [1] )
URI [1]: https://youtu.be/pgV8l5yLadQ
dcminter wrote 18 hours 26 min ago:
Or on the other side you remind me of a literal party trick - a
rubber balloon filled with helium that's starting to deflate and
thus has neutral buoyancy can be moved around without touching it.
The charges on the surface of the balloon and on your hands repel.
dcminter wrote 1 day ago:
I suppose you could take advantage of diamagnetism if a moving charge
was involved... it works for frogs :)
hammock wrote 1 day ago:
Can this be used in a bank vault?
danparsonson wrote 1 day ago:
A large steel door is a much easier and more reliable barrier
Workaccount2 wrote 1 day ago:
I actually work with high voltage for a living, and I have high
skepticism about this story. While it is technically possible if you
work out the math and somehow get an extremely dense e-field flux, from
a practical standpoint it might well be impossible. HV like they
describe, especially in high humidity, really likes to equalize itself
in a big flash.
I strongly suspect instead is that there was a spot where you could
really feel the e-field, and people just through rumor and story
telling morphed it into "the wall".
umvi wrote 1 day ago:
Maybe someone here knows a science youtuber (Veritasium/Smarter Every
Day etc) with enough clout to try to get an in with 3M or similar and
try to reproduce
fakedang wrote 8 hours 32 min ago:
ElectroBOOM!
tuetuopay wrote 15 hours 3 min ago:
I'd say styropyro. He'd be up for it. The issue is, 3M or similar
would never let him approach one of their plants :D
petee wrote 1 day ago:
What do you make of the statement that it pulled in a fly,
potentially a bird, yet repels humans?
QuadmasterXLII wrote 1 day ago:
Maybe itâs working by shocking muscles- itâs mostly acting on
creatures not objects
hinkley wrote 1 day ago:
I accept that a reel to reel could generate a high static charge
field but I would expect anything creating this level of physical
phenomenon would be dangerous to humans.
Wouldnât it be much more likely for someone walking into such a
space to become a lightning rod rather than a fly in a spider web?
EncomLab wrote 1 day ago:
This pops up at least once a month and has been thoroughly debunked.
ghusbands wrote 8 hours 20 min ago:
Got a link to one of those debunkings? (If it's so thoroughly
debunked, it should be easy.)
mmcgaha wrote 1 day ago:
I used to work for a company that bought off cuts from this plant
and the static that comes off of these rolls is scary. I heard this
story years ago and no one in our plant had a doubt about it being
true because 3M ran enormous rolls.
devnullbrain wrote 1 day ago:
See, I can believe that there are enormous EM fields in play. But
I can't believe that the employees working there would react to
them without code brown-ing.
zelon88 wrote 1 day ago:
When I was young I started my career working in manufacturing.
Specifically machine shops with presses, CNC machines, EDM
machines, ect...
You would be amazed at the level of hazard people are willing
to accept. For example, I recall running one machine, a 300 ton
press with an 84"x54" bed and 24" of stroke. It was 25 feet
tall and we nicknamed this one Optimus Prime. When Optimus was
warmed up he would spit warm hydraulic oil all over the place.
A nice fine mist along with a slurry of hydraulic rain drops
would cover the area. The solution was to wear Weimao hats made
out of disposable cardboard.
Another machine was a 50+ year old roll form machine. How I did
not lose my life on this machine is beyond me. Modern machines
feed the material automatically and have clutches and brakes
with optical sensors so they can stop on a dime. This one
literally used inertia and a massive flywheel to function. You
got the rollers spinning and fed the material into the first
roller, then as it came out you had to guide the material into
the next roller. Manually. In between spinning rollers. With
your hands. And the machine had a 1,000lb flywheel that gave
the whole thing intertia. You only needed to give it throttle
once, and the whole machine would spin for 30+ seconds whether
it was forming material, or your arm, or whatever. Chances are
it would have sucked an entire human into the rollers on one
blip of the throttle. And the coup de grâce was the throttle
was a 50lb lever on a swing pivot. If you drop this lever to
turn the machine OFF, it would bounce with gravity and bounce
itself back on. This is not a third world country. These
machines are located in Newburyport Massachusetts.
I was a lot younger back then, but to this day that is how
helicopter engine are made. Those antiquated tools are more
important to the major aerospace companies than any operator
they've ever had.
jcgrillo wrote 15 hours 56 min ago:
I had the pleasure of operating some machines like that too.
One was a hydraulic shear roughly the size of a school bus,
and once you stomp the pedal there is absolutely no taking it
back--it'll do a cycle and nothing can stop it. We also had a
Buffalo Iron Worker which I managed to misalign a punch in
once. A hefty chunk of HSS flew ~100ft across the shop and
embedded itself in the steel siding. I don't know how it
didn't hit me, because I was at the time occupying much of
the solid angle. However the machine that scared me most was
a giant drill press from the late 1800s that had a ~4' cast
iron gear on top of the drill shaft which held enough inertia
to keep the drill spinning for about a minute after the power
was shut off.
margalabargala wrote 1 day ago:
Considering that it's possible to levitate a live frog with a
(very strong) magnet without killing it, I'm able to believe
that a sufficiently strong magnetic field can be detectable by
a human without killing or immediately, obviously harming them.
AlotOfReading wrote 1 day ago:
This is an electrostatic field, which has no magnetic
component in the classical model.
HelloNurse wrote 18 hours 20 min ago:
And more practically is likely to be detected, when
approaching it casually, by discharging it through the
closest body part.
1propionyl wrote 1 day ago:
I tend to agree with you. But on the other hand, if true, this is the
kind of crazy situation that could also lead to new mathematics where
regimes considered unstable are revealed to have surprising stable
nodes.
The big problem here is that it's described as a wall and not a
progressively (quadratically) increasing field.
But what if there actually are network effects propagated by charge
carrying particles in a suitably humid environment that turn the
power of 2 into something else? Even a power of 3 could be perceived
reasonably as a wall at human scale.
It's not "I want to believe" so much as "it feels like the maths
might allow this under odd but reproducible circumstances" (my
relevant background here is in math-physics and specifically analytic
solutions to the relevant PDEs, which do have some very odd
solutions). Would be nice to see people try.
There are differences between effects we can observe between ideal
point charges and ones that only emerge as network effects when
propagated across a network of less than ideal point charges that at
least merit some investigation.
petesergeant wrote 23 hours 37 min ago:
> But on the other hand, if true, this is the kind of crazy
situation that could also lead to new mathematics where regimes
considered unstable are revealed to have surprising stable nodes.
I feel like if it was real, 3M would have immediately diverted a
bunch of money into working out how to commercialize it, and we'd
have evidence of that.
gambiting wrote 18 hours 29 min ago:
Tbf an "impassable invisible forcefield" sounds really useful for
various applications. If it was possible at all, someone would
have done some research into it, surely?
petesergeant wrote 17 hours 37 min ago:
I think we're saying the thing
gambiting wrote 15 hours 1 min ago:
Oh yeah we are, I think I'm just adding to your comment that
even if 3M ignored it then someone would have researched it.
RajT88 wrote 1 day ago:
Scotch tape produces X-Rays, so something like this feels similarly
plausible: [1] (Even if that feeling is misplaced and uninformed)
URI [1]: https://www.technologyreview.com/2008/10/23/217918/x-rays-...
maushu wrote 1 day ago:
I believe the description as a "wall" is not completely correct.
Yes, it's a wall as a unpassable obstacle, but the description they
gave when walking into it seems more like a field "can't turn
around just walk backwards".
The field was just dense enough to stop people from continuing
moving forward similar to molasses.
Workaccount2 wrote 1 day ago:
The gripe I have though is that it is incredibly hard (if not
impossible) to create a dense powerful e-field without it arcing
over.
To be powerful you need an incredibly high voltage, to be dense
you need the positive (holes, as they say) and negative charges
to be close to each other.
If you could get 5MV between two plates that are a foot apart,
that e-field would be insane an probably could do all manner of
sci-fi. But it would flash over and equalize in a picosecond.
Even if you had some kind of god tier power supply supply that
could support a constant 5MV, you would just end up with a dense
wad of plasma vaporizing everything.
DeepSeaTortoise wrote 18 hours 24 min ago:
Dunno. The breakdown voltage of vacuum is enormous. There might
be several unknown parameters at play here which would increase
the breakdown voltage of the air.
It might be but an urban legend, but the phenomenon sounds way
too fun to not look into it (or to stop spreading it should it
turn out as false, kinda like Santa)
Workaccount2 wrote 13 hours 27 min ago:
There are floating electrostatic experiments that are pretty
cool:
URI [1]: https://www.youtube.com/watch?v=U6bKDaZiy_k
TeMPOraL wrote 1 day ago:
This is the same impression I got, precisely because of this
description. If it's the effect of a field, it would seem that by
the point you notice it blocking your forward progress, you're
already rather deep in it.
Perhaps humans feel resistance/repulsive forces non-linearly?
Makes me think of magnets, too - when you have two strong magnets
oriented so they repel each other, and try to get them closer,
the effect is very strongly non-linear and, unless you're
intentionally pushing the magnets together with significant
force, can feel like it turns on almost instantly.
TimTheTinker wrote 1 day ago:
> Perhaps humans feel resistance/repulsive forces non-linearly?
That's got to be the key here. Human perception is known to be
logarithmic in so many other ways.
PicassoCTs wrote 1 day ago:
But if its a wall and you touch it - you should become part of it
and thus be unable to leave it ?
silisili wrote 1 day ago:
> He said it was actually known to the technicians for awhile before he
experienced it and they just were kinda like "meh".
I think this was my favorite part of the article. These workers
apparently hit this force field prior and just figured that was a
normal part of the job, who cares.
airstrike wrote 1 day ago:
The Board comprehensive analysis of this .
swayvil wrote 1 day ago:
A sheet of plastic. With a heavy static charge. Moving at 10mph.
Assumedly in the vicinity of a big ground.
Is that the whole experiment?
TacticalCoder wrote 1 day ago:
What's wrong on my end? I get this from both Firefox and Chromium:
Firefox: Firefox detected a potential security threat and did not
continue to amasci.com.
Chromium: https://amasci.com/weird/unusual/e-wall.html
Now "isdownorjustme" tells me amasci is down:
https://downforeveryoneorjustme.com/amasci.com?proto=https
I'm not too sure what's going on.
jeroenhd wrote 14 hours 27 min ago:
You likely have HTTPS-only mode enabled in your browser(s).
amasci.com doesn't have HTTPS configured and serves a certificate for
(.*)eskimo.com. If your browser automatically rewrites all HTTP links
to HTTPS, it'll throw these errors.
Try manually replacing https with http. Disabling HTTPS-only mode (or
HTTPS Everywhere, or whatever is causing the rewrites) might also
work.
ibizaman wrote 1 day ago:
This reads like a good SCP.
jcarrano wrote 1 day ago:
We are talking about a sci-fi style force-field here! I'd be surprised
if the military didn't secretly experiment with this.
bluGill wrote 1 day ago:
Unless engineers looked at it and said not reliable (only works with
low humidly), prone to breakdowns, and might randomly kill people.
And then some general stood up and said what is wrong with your
standard reinforced door?
TeMPOraL wrote 1 day ago:
> not reliable (only works with low humidly)
That's merely an engineering issue. Keep spraying it with water or
something. You do it right, and you might even get the familiar
buzzing and shimmering of Star Trek force fields!
> prone to breakdowns
Ah yes, that's very much like Star Trek force fields.
> and might randomly kill people
That might be an issue for Starfleet. A real-world military today
will definitely see this as a feature.
Ultimately, you're not wrong, but I would hope some military or
other entity with deep budget would try building it anyway, simply
because science isn't about "why?", it's about "why not?". I would
also imagine, should this design work and became widely-known, some
hacker would build and operate it just because.
andrewflnr wrote 1 day ago:
> A real-world military today will definitely see this as a
feature.
Real world militaries are still pretty picky about who they kill.
In particular they don't like killing their own soldiers, who are
most likely to be in the discharge path for a shield around their
own stuff.
bluGill wrote 1 day ago:
water would be high humidity not low.
TeMPOraL wrote 1 day ago:
Second paragraph of the article starts with:
> This occurred in late summer in South Carolina, August 1980,
in extremely high humidity.
But I may have misunderstood this as high humidity being key to
it happening, rather than an impediment.
bluGill wrote 14 hours 54 min ago:
Or perhaps I misunderstood, my reading was low humidity
matters, but it is quite possible that I know in general for
static high humidity shorts everything to ground and so you
don't get much static - and thus probably skimmed that part
more than I should have.
swayvil wrote 1 day ago:
You can count on that.
IAmGraydon wrote 1 day ago:
The phenomenon in question has been discussed before, and its
underlying mechanism can be attributed to electrostatics. A simple
thought experiment illustrates this concept: imagine a person with a
net electric charge approaching a similarly charged object. As they
draw closer, a force of repulsion builds up, increasing exponentially
with the inverse square of the distance.
However, a crucial aspect of this phenomenon remains unclear: how does
the charge maintain its containment? What prevents the opposing charge
from breaking through the insulating barrier and neutralizing the
charge? A fascinating analogy from the Boston Science museum offers
some insight. Picture yourself inside a gigantic, electrified sphere
â akin to a Van De Graff generator. If your charge polarity matches
that of the sphere, you'll experience a repulsive force, pushing you
toward the center. The harder you try to reach the sphere's edge, the
stronger the repulsion becomes.
This phenomenon becomes even more intriguing when considering the
context in which it allegedly occurred. A company renowned for its
innovative prowess, 3M has consistently demonstrated its ability to
harness unexpected effects and transform them into groundbreaking
products. The Post-it note's origin story is a testament to this
innovative spirit. Given this track record, it's puzzling that 3M
seemingly failed to capitalize on this electrostatic phenomenon. One
would expect the company to rigorously investigate and replicate the
effect, with the potential for a multi-billion dollar industry hanging
in the balance. Instead, the story suggests that 3M dismissed the
phenomenon as a mere curiosity.
schmidtleonard wrote 1 day ago:
Why do you think that? Negative results are boring. A failure to
publish them does not indicate a lack of investigative rigor.
Speaking of which, if you're going to complain about rigor, this is a
bad look:
> increasing exponentially with the inverse square
kragen wrote 1 day ago:
> Picture yourself inside a gigantic, electrified sphere â akin to
a Van De Graff generator. If your charge polarity matches that of the
sphere, you'll experience a repulsive force.
This is not correct. The field inside a charged conductor is zero.
You will experience no force. If there is a hole in the sphere you
will experience a repulsive force if you are close to the hole
(compared to its size).
Arnavion wrote 1 day ago:
Yes, just like with Newtonian gravity. Any inverse-square law force
will be zero inside a spherical shell. The higher force from parts
of the shell closer to you is exactly canceled out by the farther
parts exerting less force but there being more of those farther
parts.
URI [1]: https://en.m.wikipedia.org/wiki/Shell_theorem
kragen wrote 1 day ago:
For gravity, it's only true for spherical shells, but in the case
of charged electrical conductors, it's true no matter what the
shape of the shell is. The field inside a charged, conductive
small stellated dodecahedron is also zero everywhere inside.
That's because the charge in the conductor migrates as long as
there's an electrical field to make it migrate; it stops moving
once it neutralizes the field.
(If you made an actual small stellated dodecahedron with
infinitely sharp points, the charge would leak away from the
points via field emission. Or, in theory, you'd have an
infinitely strong electrical field there, and therefore all kinds
of singularities. But reasonable approximations of the setup are
possible in real life.)
1970-01-01 wrote 1 day ago:
Selling tickets on those non-humid days would have been more profitable
than fixing anything.
lxgr wrote 1 day ago:
Static discharge from machines like that has killed people in the
past, so Iâm not sure if thatâs the best idea.
viraptor wrote 10 hours 59 min ago:
Amusement parks have killed people in the past, yet they're still
queuing up to the machines able to do the most damage.
lxgr wrote 9 hours 22 min ago:
Amusement parks are slightly more systematic about trying their
best to not kill people than "let's see what happens if people
interact with this known-deadly machine when we remove the part
that makes it less deadly (i.e. the grounding)".
viraptor wrote 9 hours 11 min ago:
It's just a difference is scale of risk. For something closer:
base jumping is still popular, no-harness climbing of tall
buildings is still a thing on YouTube, crazy Russian groups
still do pull-ups on construction cranes.
dyauspitr wrote 1 day ago:
If this was reproducible I could think of so many real world uses.
Invisible force fields that can move hundreds of pounds is a holy grail
in several fields.
rUsHeYaFuBu wrote 1 day ago:
Ever see an electromagnet crane at a junk yard? [1] You can make one
yourself with a nail, some copper wire, and a battery.
URI [1]: https://youtube.com/watch?v=XBWy9gzGGd4&pp=ygUVZWxlY3Ryb21hZ...
dyauspitr wrote 1 day ago:
Can an electromagnetic move organic material?
jhgorrell wrote 1 day ago:
Extremely powerful fields can levitate a frog - so yes.
URI [1]: https://news.harvard.edu/gazette/story/2024/04/how-did-y...
kragen wrote 1 day ago:
Probably not in a useful way; the induced currents would produce
far too much heat.
rUsHeYaFuBu wrote 1 day ago:
If it's strong enough, probably. I mean, MRIs kind of work that
way.
SigmundA wrote 1 day ago:
Yes the 45 Tesla magnet in Tallahassee can levitate small non
ferrous things like a strawberry in a little tube and draws 56
megawatts about 7% of the cities power grid.
swayvil wrote 1 day ago:
That's pretty darn far from what we're talking about here. The
comparison is absurd.
rUsHeYaFuBu wrote 1 day ago:
How so? It's literally an invisible (to the eye) field that can
lift hundreds of pounds.
And magnetic fields are directly related to electric fields. It's
called electromagnetism for a reason.
function_seven wrote 1 day ago:
Of metal, yes. That's not what we're talking about here. We're
talking about force fields in the sci-fi sense. An invisible
wall that a person can't pass through.
rUsHeYaFuBu wrote 1 day ago:
The article is about an electrostatic field. That's far from
sci-fi.
URI [1]: https://en.wikipedia.org/wiki/Electric_field
function_seven wrote 1 day ago:
I was clarifying the sense I was using the term "force
field". Not a generic field of electromagnetic forces, but
the fantastical one that can contain arbitrary matter.
Like the one described in the article, that a person was
leaning against and could not pass through. If this were
something that we could reproduce, it would have awesome
real-world uses. Like a real hover board! Or the best
anti-theft protection for my parked car.
rUsHeYaFuBu wrote 1 day ago:
You could though. Given a sufficiently strong enough
positively (or negatively) charged electric field and
yourself equally positively (or negatively) charged
sufficiently you could have an 'invisible' wall that you
couldn't walk through. Assuming that neither yourself or
the field you're walking into has anywhere to discharge
to.
baggy_trough wrote 1 day ago:
Wouldn't a field strong enough to somehow produce this effect be more
likely to short out on anything, taking you out like a bug zapper?
VikingCoder wrote 1 day ago:
[1] "The article says that because of the insulating nature of the
floor and and footwear, no discharges occurred."
URI [1]: https://skeptics.stackexchange.com/questions/53985/was-an-in...
Noumenon72 wrote 1 day ago:
From my experience rolling up 1500-pound rolls of plastic, it will
start arcing out a few feet to the metal of the winder when it gets
strong enough.
Charge builds up over time, so there ought to be some discussion of
how the field changed between 0 charge and the invisible wall
state.
rUsHeYaFuBu wrote 1 day ago:
Yeah I'm not sure this story makes sense either. Shoes may act as an
insulator but wedding rings and belt buckles would presumably
conduct.
Additionally potential differences tend to attract rather than repel
unless these individuals were also charged with the same polarity as
the field as far as I know.
baggy_trough wrote 1 day ago:
Good point, a repulsive effect would have to be the same charge
sign so no bug zapper.
bongodongobob wrote 1 day ago:
Conduct... to where?
rUsHeYaFuBu wrote 14 hours 33 min ago:
To your body.
throw-qqqqq wrote 11 hours 44 min ago:
No :) There must be a difference in electrical potential for
current to flow between two points.
If the body is insulated from ground, the body is at the same
potential. No current flows. No material conducts anything :)
For the same reasons, high voltage repairs can be done live
from a helicopter: [1] Around 1:10 you can see the lineman
connect the mains to the helicopter, to neutralize any
potential difference.
After that, the lineman and the helicopter are at the same
potential as the cable, so no current flows.
If someone dropped a line from the heli to the ground however..
zap!
URI [1]: https://m.youtube.com/watch?v=9YmFHAFYwmY
gridspy wrote 1 day ago:
When someone is talking about insulating shoes their point is that
the body is electrically isolated from the floor. Without that
isolation charge can travel between the two. Concrete and skin are
fairly good conductors by comparison with air or insulators.
Wearing a conducting ring might make it easier for charge from the
air to move into your body through your skin - but it will not make
it easier for that charge to get to the floor (and then to ground)
from your body.
bluGill wrote 1 day ago:
Generally when people talk about shoes (or tires) they are
talking about voltages that can jump the distance from their foot
to the ground through air - around the shoe.
Most shoes are not great insulators - they insulate but how knows
who much. electricians sometimes buy special shows that do
insulate. Those shoes come with care instructions and dust on
the outside compromises their insulation.
gridspy wrote 9 hours 28 min ago:
While you raise some valid points, you need 10kV to jump a 1cm
gap. So in a domestic situation at the much lower voltage
involved (130V / 250V) I imagine you don't need to worry so
much about the air gap.
The care instructions and dust you mention sounds likely to be
super important when you're casually touching live stuff while
standing on a grounded floor.
In an electrostatic situation, the electrons can flow (almost)
freely without the shoes / tyres and so a large differential
between body / ground will not build up. With shoes, you'll
need a large difference to build up (10kV? 20kV? More?) before
it discharges.
Anyway, there is clearly a difference between these situations
- even if the shoes don't provide magical protection. But the
shoes are not magical, as you correctly describe.
rUsHeYaFuBu wrote 1 day ago:
> Wearing a conducting ring might make it easier for charge from
the air to move into your body through your skin.
Which would likely make you a pretty nice load or resistor!
gridspy wrote 9 hours 33 min ago:
The skin is very resistive, the body itself is not. There is a
soldier who "won the darwin award" by taking the probes of a
multi-meter and after measuring their skin resistance decided
to measure their internal resistance.
After piercing the skin, the test current from the multimeter
(9v) was sufficient to electrocute this person. Sadly it
(apparently) was a fatal injury. I couldn't find a reference,
but the logic makes sense (50V sufficient to kill normally,
skin is most of the protection).
When dealing with electricity, having items which reduce the
protection your skin offers (metal rings, moisturizer, etc) is
a substantial risk.
throw-qqqqq wrote 1 day ago:
No, you need a path to ground for any current to flow. You need
a difference in electrical potential more specifically.
When insulated, there is no difference. Your potential is
âfloatingâ.
gridspy wrote 6 hours 3 min ago:
Well, more correctly the difference needs to exceed the
breakdown voltage of the insulation barrier. Or (depending on
the insulator) some current might flow the entire time, but a
limited amount.
boxed wrote 1 day ago:
I wish Mythbusters still existed to test stuff like this.
viraptor wrote 11 hours 2 min ago:
When they still did, they had an idea submission forum. I did post it
there and the moderator responded with something close to "it's been
submitted, not interesting, just try it yourself". I'm still annoyed
at them for that stupid response.
sonofhans wrote 1 day ago:
Can you imagine the expense? âWe need 1 mile of poly film, 20-feet
wide â¦â
qingcharles wrote 1 day ago:
I worked briefly in a factory where they had these giant rolls
arriving daily... they were put onto a machine that would spool
them off onto smaller rolls (say 100ft) and chop them. It's
definitely something commonplace.
harrall wrote 1 day ago:
Rolls like those were common in the warehouse at the place I
worked.
SequoiaHope wrote 1 day ago:
A 5000 foot long roll of plastic is common. Here is a 50 inch wide
roll that is over a mile long which costs $400: [1] Or here is a 20
foot wide roll 1/10th of a mile long: [2] Based on the cost of the
roll from McMaster, a wider roll with the same cost basis would be
$2000.
URI [1]: https://www.mcmaster.com/19575T43
URI [2]: https://www.uline.com/Product/Detail/S-20063/Plastic-Sheet...
observationist wrote 1 day ago:
An experimental setup, including the land and a new used steel
construction could cost less than $500k. Someone could throw a
couple million at it to control for humidity, temperature,
airflow, etc, with all sorts of variety, and it could be a lot of
fun.
If something like this could be made safe, I imagine there are
applications in security and process safety in places like
nuclear power, water treatment, any facility where you want to
restrict access in an extreme way. I'd imagine that it would
never be safe, any discharge is going to fry whatever completes
the circuit.
littlestymaar wrote 1 day ago:
> Someone could throw a couple million at it to control for
humidity, temperature, airflow, etc, with all sorts of variety,
and it could be a lot of fun.
That's the kind of projects I'd fund if I were a billionaire,
not trying to buy the biggest yacht â¦
danparsonson wrote 1 day ago:
And once you'd worked it out, you could buy a yacht with a
force field!
tmjdev wrote 1 day ago:
I've read this many times over the years, sort of enamored by how such
a strange phenomenon popped out of a factory setting.
In the most 2016 update the relative says it's common to see weird
effects from the spools. If it's so common it should be reproducible I
would think, yet I've never seen it done.
dekhn wrote 1 day ago:
I've seen this happen in a wide range of production environments
(both industrial and computing). Not this effect specifically, but
"odd emergent behavior that occurs only at scale that is non-obvious
and state-dependent". For example I work at a company that grows a
lot of cells is massive reactors, and some folks who run the largest
reactors commented that they saw slow changes in overall production
that were not explainable by any observed variable (we speculated
that slow genetic drift occurred in populations, but it may also have
been seasonal, or due to unobserved variables). And when I worked at
Google, there were definitely cluster-wide things that you'd only
notice if you were very knowledgeable and attuned to their ongoing
processes.
My guess is that this happens in nearly all large-scale production
systems but goes mostly unobserved.
TeMPOraL wrote 1 day ago:
In case of this "invisible electrostatic wall", there were likely
significant amount of people in that company who were at least
somewhat into Star Trek[0], so I'd expect more than mere "meh, this
happens" from people who had just seem to have accidentally
invented a force field. It's not merely a weird emergent behavior,
it's a behavior closely resembling a sci-fi technology, and
therefore likely to have similar applications - so quite obviously
a potential money and fame printer.
--
[0] - Which was well-known around the time of that event, and at
its peak of popularity when the report in the article was filed!
dekhn wrote 1 day ago:
When you work in production and have quotas to meet, you often
ignore interesting side-effects. When I worked at google I
worked at global cluster scale and frequently saw any number of
events that in themselves would have been
graduate-student-for-two-years projects that I had to force
myself to ignore so I could get my main work (large scale protein
design using 1-3 million cores in prod) to finish.
As a side note, always test any global-scale torrent system for
package distribution carefully, as sometimes the code can have
"accidentally n**2" network usage that only shows up when you
have a worldwide grid of clusters.
gopher_space wrote 1 day ago:
> My guess is that this happens in nearly all large-scale
production systems but goes mostly unobserved.
Not unobserved. Unremarked maybe? It's expected behavior that
leads us into personification of systems e.g. calling ships 'she'
or talking about temperament between similar machines on a line.
empathy_m wrote 1 day ago:
I think the disappearing polymorph stories are also pretty spooky.
These have real-life impacts, like with ritonavir.
MarkusQ wrote 1 day ago:
Every time I look into those I come away thinking that Occam's
Razor would suggest a different explanation: the original
characterization was, knowingly or not, incorrect. Patents so
frequently fail to contain sufficient information to allow a
practitioner skilled to in the appropriate arts to reproduce the
claims that it seems more plausible that the disappearing
polymorph stories should be reclassified as "someone was caught
fibbing" stories. In the replication crisis, we don't assume
that the problem is that something about the world has changed,
we assume that the original was flawed, and we should do the same
here.
It would be much more convincing if there were more cases that
weren't economically significant. A strange property of
chemistry that only comes up when money and lawyers are involved
seems inherently suspicious.
empathy_m wrote 1 day ago:
I skimmed the literature on this and the ritonavir story seems
legit.
There really is a peer-reviewed paper saying that there are
five crystalline forms of the stuff. ("Elucidation of crystal
form diversity of the HIV protease inhibitor ritonavir by
high-throughput crystallization", Applied Physical Sciences,
Feb 2003).
It really does seem that in 1998 the more stable Form II
suddenly started coming out of the factory, with lower
solubility and such bad oral bioavailability that the oral
capsules were withdrawn from the market until Abbott figured
out a new way to make the drug. (I think they were already
moving from a capsule to a gelcap and the gelcap didn't have
the same issue? Just reading ⦠this is not such a good source
perhaps but lovely bare HTML: [1] )
URI [1]: https://www.natap.org/1998/norvirupdate.html
toast0 wrote 1 day ago:
From experience with large scale clusters, yeah. Weird stuff
happens. But it's very hard to setup a test cluster that is
actually representative, and you can only do so much on a live
cluster. Occasionally, I have been able to find explanations for
some of the weird behavior, but usually it's like here's a bug in
Linux packet forwarding that was fixed in Linus's tree 15 years
ago, but apparently has never been deployed to some router, so it's
just going to keep aggregating input packets because large receive
offload, and then drop them with needs frag because the aggregated
packet is too big to forward. sigh (that's not exactly a cluster
scale issue, but it's the most relatable example of an
investigation that comes to mind)
You're pretty unlikely to get academic papers when the required
setup involves having 100M+ clients geographically dispersed. And
it's going to be very hard for peers to reproduce your findings.
swayvil wrote 1 day ago:
It reminds me of that experiment where they had an audience of 1000
focus their attention upon a chair on a stage.
krackers wrote 1 day ago:
What happened?
swayvil wrote 1 day ago:
The chair got chairier.
I don't recall what that means.
egypturnash wrote 1 day ago:
Do you recall anything that would make it possible to find
any descriptions of this experiment? When I try to search for
"a thousand people focus attention on a chair" I just get
stuff about meditation and an "ADHD chair". Which is
apparently a thing.
xobs wrote 15 hours 2 min ago:
It sounds vaguely like the Invisible Gorilla Experiment:
URI [1]: https://en.m.wikipedia.org/wiki/The_Invisible_Gori...
swayvil wrote 1 day ago:
I'll see what I can find
avidiax wrote 1 day ago:
Ever notice how UFO and Bigfoot sightings mostly went away once
everyone had a 4K60 video camera in their pockets?
One thread about this in 1995, and then the phenomenon is never seen
nor heard about again . . .
stackghost wrote 11 hours 10 min ago:
Not sure about Bigfoot but isn't it pretty well-established that most
UFO sightings were the SR71?
wombatpm wrote 22 hours 0 min ago:
We had plenty of UFO sightings over the last couple of years.
Remember the navy pilots? The drones a few months back?
Big Foot, sadly, has been displaced by climate change and was forced
to relocate to Canada
t-3 wrote 20 hours 1 min ago:
I just assumed those were made up in an attempt to get more budget
for the military.
shepherdjerred wrote 1 day ago:
URI [1]: https://www.xkcd.com/2572/
tedunangst wrote 1 day ago:
They even went home and came back the next day. Why not bring a
camcorder along?
hammock wrote 1 day ago:
What does this comment have to do with OP?
mrandish wrote 1 day ago:
> One thread about this in 1995, and then the phenomenon is never
seen nor heard about again . . .
A default mode of skepticism is best, however the story of this
incident didn't trigger my "Yeah, probably not" reflex. It is based
on known physical principles and the extremely unusual context seems
in the ballpark of sufficient to potentially cause something like
this. So my assumption was this was an extremely unlikely edge case
that happened "that one time."
It's also not something which strikes me as being a thing people who
work in a large 3M factory would lie about.
dist-epoch wrote 1 day ago:
> It is based on known physical principles
What exactly does it repel against a human? And why would it repel
instead of discharge?
tshaddox wrote 1 day ago:
I'd say UFO mania is more intense and more mainstream than ever.
Still no remotely compelling physical evidence, of course.
aftbit wrote 1 day ago:
I'd say anyone who doesn't believe in UFOs is just not observant
enough. That doesn't mean aliens among us or secret government spy
planes, but if you watch the sky long enough, you'll see some odd,
hard to explain things.
lxgr wrote 1 day ago:
On the other hand, we just witnessed a nationwide drone panic, and
not for a lack of video evidenceâ¦
An odd phenomenon being rare and hard to document is neither proof
nor evidence of absence for it existing.
EA-3167 wrote 1 day ago:
I think it's telling that said panic was short-lived, and to anyone
watching the video, laughably silly. Unless you're a psychologist
studying the dynamics of digital crowds, it probably isn't very
interesting at all.
By contrast that same "panic" would probably have been framed as
UFO's and an alien invasion pre-smartphone era.
lxgr wrote 1 day ago:
I personally really wouldn't bet on there being less UFO
believers these days than before the ubiquitous availability of
cameras.
EA-3167 wrote 1 day ago:
I wouldn't bet on that either, but they're less mainstream,
less respected, and most of us no longer feel a particular urge
to humor them. Every passing year makes them less relevant, and
more like the sort of people who believe in any other
conspiracy theory or magical belief system.
Which is frankly where they always belonged.
pjc50 wrote 15 hours 13 min ago:
> the sort of people who believe in any other conspiracy
theory or magical belief system
Bad news: this has gone completely mainstream. We're deep
into government by conspiracy theorists.
jsight wrote 1 day ago:
At the other end of the spectrum, the belief that the moon
landing was faked seems to be steadily increasing in
popularity. I don't get it at all.
EA-3167 wrote 1 day ago:
We made some fundamental mistakes when it comes to the
subject of why people believe what they believe. The polite
and intellectual answer to that has a lot to say about
evidence and reason, replication, publication, review...
but that simply doesn't move most people. That isn't how
most people live their lives. MOST people operate on
networks of trust, because they lack the interest or the
capacity to make informed decisions about many things. They
don't know how a nuclear power plant works, they don't know
anything about monoclonal antibodies, but they know people
and places they trust. Their "smart" and "informed" social
networks, their doctor, their priest, etc.
Unfortunately those networks of trust are easy to corrupt,
not for everyone, but for a large number of people.
mrandish wrote 1 day ago:
> magical belief system.
To be fair, if one includes religions this is significantly
more than half the population. Add in astrology, psychics,
ghosts, crystals, auras and other common 'woo' and it gets
higher still. Sadly, HN is not a representative population
sample. Skeptical non-believers are still a minority in the
modern world.
jacoblambda wrote 1 day ago:
Not just one thread.
ANTEC '97 Conference Proceedings, CRC Press, pages 1310-1313. [1] The
thread is based on a conference talk and journal publication that
preceded it.
The reason this particular case hasn't been reproduced is just
because it has no practical application, requires a lot of equipment,
requires the equipment to be intentionally improperly operated
risking damage or injury, and it's extremely expensive to test.
Nobody is going to willingly tool up an environment capable of
running a mile of 20 foot wide PP film at a thousand feet per minute,
then purposely ungrounding the equipment, and run it at 100+ F and
95+ % humidity for hours, days, or weeks. Just setting it up would
cost millions of dollars and running it may cost millions more.
URI [1]: https://www.google.com/books/edition/SPE_ANTEC_1997_Proceedi...
actionfromafar wrote 7 hours 48 min ago:
URI [1]: https://web.archive.org/web/20160308070438/http://centxesd...
Animats wrote 1 day ago:
Ah. Nice to have a solid reference.
It's not an unusual problem. Anything which moves thin sheets of
insulating material at high speed can cause this. And so, there are
standard devices for dealing with it.
The simplest is copper tinsel. That's even available at WalMart.[1]
There are fancier systems. [2] The static eliminator doesn't have
to touch the product. Close is good enough. Maybe 1 inch for
tinsel, much greater for the active devices. [1]
URI [1]: https://www.walmart.com/search?q=anti-static+tinsel
URI [2]: https://www.takk.com/wp-content/uploads/2024/01/2023-TAKK-...
hinkley wrote 1 day ago:
I miss MythBusters.
KennyBlanken wrote 1 day ago:
I don't. It was shitty experiments presented to the clueless
public as an example of how science works. The experiments
usually did a terrible job of actually testing things, were so
badly designed they malfunctioned more than anything else, and
half the time they'd get results that were at best inconclusive
or seems one way and they'd just declare it to be the other.
I think those two clowns did more to harm scientific literacy
than almost anyone else except maybe the Texas Board of
Education. Not to mention, Adam is pretty well known for being a
tool.
Daneel_ wrote 15 hours 7 min ago:
That's certainly not the take away I have from the show. It
inspired many to think for themselves and made science
approachable and fun. They made a genuine effort to be
scientific within the bounds of the show. I think they've done
a great service to the field, personally. Can you cite any
sources for Adam being a 'tool'? He seems like a high-energy
kind of guy, but this is the first I've heard of him being
disliked by crew. Usually I've heard the opposite; that he
gets on well with other crew members.
Aurornis wrote 1 day ago:
> Just setting it up would cost millions of dollars and running it
may cost millions more.
You're a couple orders of magnitude too high.
Polypropylene film isn't that expensive. A thousand feet per minute
is only 10 miles per hour, which is not that fast at all. Humidity
and heat aren't hard to generate in a closed space.
This is the kind of thing that's within the budget of some
ambitious YouTubers, not millions of dollars.
It's a fun urban legend. The red flag for anyone who has studied
anything related to electromagnetism is the way it's described as a
wall, not a force that gradually grows stronger as you get closer.
Forces don't work at distance like that.
You also have to suspend disbelief and imagine this force field
didn't impact the equipment itself. We're supposed to believe that
a grown man can't push up against the field at a distance away from
the source, but the plastic film and machinery inside of the field
are continuing to operate as usual?
It's a fun urban legend. Leave it be, but don't take it seriously.
comex wrote 1 day ago:
> The red flag for anyone who has studied anything related to
electromagnetism is the way it's described as a wall, not a force
that gradually grows stronger as you get closer. Forces don't
work at distance like that.
You might be taking âwallâ too literally. I have no trouble
believing that someone would call it a wall even if the force did
gradually grow stronger over a significant distance.
joemi wrote 1 day ago:
The article mentions "50K ft. rolls 20ft wide". While you might
not need the full 50K ft length (if you can even buy such a roll
with less length), the 20 ft wide spec is probably fairly
important. I wonder how much that'd cost, including
transportation? Also, I have no idea how much it'd cost to buy or
make machinery and supports to sufficiently handle such a sized
roll. What are you estimating these costs would be?
jacoblambda wrote 1 day ago:
> it's described as a wall, not a force that gradually grows
stronger as you get closer. Forces don't work at distance like
that.
It's described as a wall because it's not just running a straight
line. The PP line creates an archway where the "wall" is located.
That's where the field is most intense. It's noticeable elsewhere
but that's the point where as indicated in the paper they can no
longer push through it.
> You also have to suspend disbelief and imagine this force field
didn't impact the equipment itself. We're supposed to believe
that a grown man can't push up against the field at a distance
away from the source, but the plastic film and machinery inside
of the field are continuing to operate as usual?
This is also addressed in the paper. The lines can run 50-100%
faster than it normally does but the faster they run it the more
problematic the interference is. So during normal operation they
limited it to 750-1000fpm.
dist-epoch wrote 1 day ago:
> The reason this particular case hasn't been reproduced is just
because it has no practical application
It can be a tourist attraction you sell tickets to.
bluGill wrote 1 day ago:
Can it? Or are their safety aspects that make it dangerous in
enough situations that you shouldn't let the public there. I
wouldn't be surprised if it was mostly safe but once in a while
there was a deadly spark. For sure I wouldn't let someone with a
pacemaker or similar device near this. I also wouldn't allow
phones, wallets, key - anything with electronics - near.
dotancohen wrote 1 day ago:
In the fine article it is mentioned that the plant manager
debated whether to fix it or sell tickets.
Workaccount2 wrote 1 day ago:
There are much easier and cheaper ways of generating megavolts of
electricity, I think the biggest barrier would be getting someone
who knows enough about this to build it despite their skepticism
about the validity of it.
J0nL wrote 8 hours 24 min ago:
I remember hearing about this in the mid 2000s, someone at
Brookhaven (US DOE/Army) jumped on filing a patent for it and
dubbed it a plasma window.
They found a use for it in particle accelerators to partition off
sections that are under vacuum
jacoblambda wrote 1 day ago:
Sure but for creating fairly uniform/gradual fields of static
electricity over a large space?
Electrostatic precipitators exist but they aren't large.
Everything else I'm aware of that works on larger scales fails to
satisfy the uniform/gradual aspect.
dotancohen wrote 1 day ago:
That is what grants are for. And DARPA when something more
specific, like this, is to be investigated.
giantg2 wrote 1 day ago:
"And DARPA"
That was my first thought - the military would be all over this
if there's even a remote chance you could build energy shields
or something.
sunshinesnacks wrote 1 day ago:
According to [1] , 100 deg F with 95% RH is a heat index of 185 F.
The linked paper says "temperature often approached 100 F with
relative humidity above 95%," and later references specific
conditions of 92 F and 95% RH (137 F heat index).
Are these sorts of heat index values feasible for a plant
environment? The line about 100/95 seems almost hyperbolic, which
doesn't help with credibility in my opinion. Maybe I'm missing
something.
URI [1]: https://www.weather.gov/arx/heat_index
pixl97 wrote 1 day ago:
There are a lot of places in plants that can end up being deadly
for any extended amount of times in particular weather
conditions.
There was a grain processing plant up in the midwest were my dad
worked that had an area enclosed in between building they'd close
off access to on the hottest summer days. Light would be
excessively focused in that area from other buildings, and
moisture from other processes and lack of air circulation lead to
deadly wet bulb temperatures.
jacoblambda wrote 1 day ago:
That's basically normal for unconditioned factory spaces in the
US south during the summer. Ungodly hot, ungodly humid, and
generally just shit to exist inside.
This is in large part why historically industrialized factories
tended to be concentrated in colder, higher latitude regions
until the 20th century. Without refrigeration the work was far
harder and more exhausting for the workers and that limited
efficient use of labor.
sunshinesnacks wrote 1 day ago:
I've spent a little bit of time in those types of spaces. I
absolutely believe the temperatures referenced, but approaching
100 F with humidity above 95% is likely deadly in a short
amount of time. And to then seemingly make jokes about selling
tickets to walk into an area where you get physically stuck for
mysterious reasons adds to my opinion that some of the report
seems hyperbolic.
Check out the heat index page I linked above, or this similar
one from OSHA: [1] .
URI [1]: https://www.ohsa.com.au/services/heat-stress-monitorin...
jacoblambda wrote 1 day ago:
Yeah it can be deadly but it is unfortunately quite common.
People adapt to it and can tolerate longer spans in it but
it's still super taxing and requires regular breaks if you
are doing any amount of serious activity. And of course lots
of fans and anything else that can raise the evaporation rate
and heat dissipation help.
The jokes ngl sound like the exact type of humor you'd expect
from people who work out on the floor. Basically "oh well
that's fucking horrifying, I bet we could make some money
selling tickets".
lazide wrote 22 hours 37 min ago:
Iâm sorry, but you have no idea what you are talking
about. 95% relative humidity means sweat wonât evaporate,
and there is no evaporative cooling. 100F external temps
are above cooling temps and near dangerous baseline body
temperatures.
100+F + 95% relative humidity will literally kill people,
regardless of adaptations. Fans wonât help.
Fatal core temperature ranges are so close, even baseline
metabolic heat can kill someone from hyperthermia in those
conditions.
[ [1] .]
In a general environmental sense, current estimates have
95F outside temps and 95% relative humidity being the point
where mass die offs of mammals start to occur. Itâs a
major concern with global temperature changes [ [2] ].
Skin temperatures > 95F (which will occur if air temp is
95F or higher and there is no evaporative cooling ability)
inevitably lead to hyperthermia even in fit and acclimated
individuals - even at rest
Most of the time, people just donât realize what the
actual relative humidity is. âTerribly humidâ is
usually more like 60% RH.
95% is saturated, often foggy/misty.
âAt least itâs a dry heatâ in Deserts, which allows
people to survive high temps, are often 5-10% relative
humidity or even lower. There, the biggest challenge is
staying hydrated enough to sustain the rapid loss of water.
In some situations itâs possible to lose a gallon an
hour. But itâs possible.
In 95% RH, that gallon makes no difference and youâll
flat out die instead.
URI [1]: https://pmc.ncbi.nlm.nih.gov/articles/PMC10010916/...
URI [2]: https://www.pnas.org/doi/10.1073/pnas.0913352107
Taek wrote 13 hours 15 min ago:
The amount of arrogance in this thread about what
temperatures become fatal is baffling. Hyperthermia is
not something that kills you on the timeline of minutes
or even hours at wet bulb temperatures of 100F+, or even
105F+.
Remember, when people get sick it's not typically fatal
for them to hold a body temperature of 104 degrees, even
if sustained for more than 24 hours. Being in a work
environment at 95+% relative humidity and 100F is going
to be unpleasant, but as long as you are well adapted to
it and you get to somewhere cooler within a few hours you
are going to be fine.
People push well beyond a wet bulb of 105F in saunas all
the time, often sustained for 30+ minutes. I think if you
had yourself ever been in a room that's 110F and 100%
humidity (meaning it's literally raining continuously
from condensation) you'd realize that it's really not
that extreme of a temperature, and that it takes hours
for your core to heat up to a place where you will be at
risk of dying.
lazide wrote 13 hours 3 min ago:
I know of at least one instance where several well
acclimatized individuals died in less than 15 minutes
in open air in the Grand Canyon above the Colorado
River due to solar heating and 95% wet bulb humidity.
Iâd argue you just havenât actually been in those
types of situations either. In that case I think they
estimated 110ish air temps.
But maybe Iâm misremembering - I heard it from the
investigating safety officer though.
I have yet to see anyone actually able to work or
function in actual 100% humidity and 100+ degrees temps
for more than a few minutes before having serious
problems.
Iâve seen plenty of people have problems in 60%
humidity which everyone agreed was terrible. Mostly
heat stroke.
Peopleâs core temp is already just a hair under 100F,
and even at rest are producing 100ish watts of thermal
energy. It really doesnât take much for it to start
spiking if cooling is literally impossible.
jacoblambda wrote 11 hours 39 min ago:
With 100% humidity you definitely can't survive or
function but with 95% at 100F exactly it's just
barely feasible. That gives you just enough margin
due to evaporative cooling that with sufficient air
flow you can maintain a temperature of 97-98F via
evaporative cooling. And importantly this only works
in the shade. Outdoors it's unlikely to be feasible
due to the rise in surface temperatures due to
thermal radiation from the sun.
That of course requires a strong fan blowing and
regular, heavy hydration to sustain but it's
feasible. So it's workable in an industrial
environment where you can adjust the environment
enough to get by but outdoors in large wild spaces
like the Grand Canyon (as per your example) it's
unlikely to be survivable for long.
And notably in an indoor environment there is a big
difference between an operator running a machine or
vehicle and an individual under heavy exertion. The
added thermal stress of heavy exertion makes it less
survivable as well.
So in the end it only really works in factory
settings because:
- There's no sun to add radiative heat.
- There's fans and ventilation to maintain
evaporative cooling.
- Workers can take regular or semi-regular breaks in
a cooler or lower humidity environment to recover
some from the thermal stress and to recover water and
electrolytes.
- Those workers can limit their activity to rates of
exertion/heat production that don't exceed the
limited evaporative cooling they have access to.
As soon as you remove one of those advantages or
increase the temperature much above 100F or increase
the RH above 95%, survivability becomes way less
likely.
sans_souse wrote 1 day ago:
Tell me about it. I worked for 3M owned Saint Gobain running
kevlar and fiberglass sheets thru 5-story oven feeds. it was
often 105°F on the floor, but if you were unlucky enough to
lose your line you'd be hiking up 5 stories of oven stacks
where temps would be soaring. Not to mention every Friday PM
shift would start with running junk lines super hot to "clean"
(burn-off) all the accumulated Teflon in the oven walls and
exhausts (which did not work efficiently enough) from the prior
week. So, at 3PM you would start your shift already drenched in
sweat watching as a Teflon smoke plume formed at the ceiling of
the 7-story plant, like a dark storm cloud, and slowly make its
way down to the floor. By 10PM we would all be coughing and
exhausted, scratchy throats, etc.
A lady on 3rd shift who ran my machine had a near death
incident and the company swept that under the rug along with
plenty of other seriously concerning practices.
AMA!
ambicapter wrote 1 day ago:
That job sounds like literal hell on earth.
sunshinesnacks wrote 1 day ago:
I don't doubt those temperatures at all. But do you know what
the relative humidity was? It's the combo that causes
problems fast. 100 F and 60% RH is miserable and dangerous,
but that's a wet bulb of about 90 F, so there's some marginal
potential for your body to cool itself. 100 F and 95% RH is a
WB of 98.6 F. Any heat generated in your body has no where to
go.
sans_souse wrote 1 day ago:
Oh, I didn't mean to imply I experienced any force field
effects. I dont recall the humidity, but I do recall
looking up OSHA rules regarding heat, and they only offer
"guidance", nothing is regulated or enforced solely based
on the temperature but they do reference relative humidity.
onlypassingthru wrote 1 day ago:
A funny thing happens to those who live or train in extreme
environments, their body adapts over time. You or I might
pass out if we were suddenly exposed to that sort of
factory environment, but an experienced worker might handle
limited exposure just fine. The human body is amazingly
adaptable.
lazide wrote 22 hours 39 min ago:
Nah, that will literally kill any human in potentially
minutes. No one can heat adapt to 100F + 95% relative
humidity. It literally will cook you dead.
onlypassingthru wrote 8 hours 0 min ago:
Nope. A human that is regularly exposed to such
environments has probably developed a strong cutaneous
vasodilation response and can tolerate limited exposure
just fine. Instead of a cold plunge in a frozen pond,
they're doing a sauna. Human bodies are amazingly
adaptable.
Taek wrote 13 hours 28 min ago:
Not at all. I've spent plenty of time (sessions
exceeding an hour) in saunas that were >105F and >95%
humidity (literally so much steam that it was
continuously raining from the condensation).
Remember that when you get a fever, your internal body
temp can jump to 103+ and stay there for days. Even at
a wet bulb temperature above 110, it's going to take
time for your internal temperature to heat up to that
level. There's nothing "potentially in minutes" about
it for humans that are used to the heat.
Sure, you do eventually have to get somewhere cooler.
But a wet bulb temperature of 105F is not going to be
fatal for a well adapted human even after a few hours.
anymouse123456 wrote 15 hours 41 min ago:
Nah. This doesn't pass the smell test.
Throughout much of the Southeastern United States, we
regularly see Summer temps above 100F (37C), and
humidity up to 90%.
One of the two Marine Corps training bases is in South
Carolina where temps and humidity are often near these
values and sometimes crest them.
Most of Florida frequently passes these values every
Summer.
While it is not comfortable, I can assure you, most
humans are able to exert themselves without being
killed in minutes from this kind of exposure.
myrmidon wrote 14 hours 48 min ago:
Those do NOT occur regularly in the US at the same
time (because the humidity peaks in the morning, but
the temperature in the afternoon). Maybe in a few
decades though.
35°C at 100% humidity is about the human
survivability limit (at 6h exposure). This makes a
lot of sense because humans generate ~100W of heat,
but require their core temperature to stay constant--
if the environment is too hot and evaporation
ineffective because of humidity, then your
thermoregulation just breaks down and you die, just
like from high fever.
dylan604 wrote 1 day ago:
> 100 deg F with 95% RH is a heat index of 185 F.
So just a typical summer day in Texas
swayvil wrote 1 day ago:
We could design the experiment. Then try to reduce the experiment
to a cheap, convenient form.
Surely somebody has done at least that.
Mistletoe wrote 1 day ago:
Bigfoot and ghosts yes, but the recent drone mania seems to have
increased. :) Maybe they would have been called UFOs before we had
video to look back on.
colechristensen wrote 1 day ago:
A lot of the recent drone mania is people taking videos of
airplanes and helicopters. At this point I don't know how many of
these videos are making fun or the paranoid people.
ceejayoz wrote 1 day ago:
Yeah, my local news had a clip that was clearly an American
Airlines tail logo.
giantrobot wrote 1 day ago:
That's the best way to disguise UFOs! Shape them like airliners
and carry passengers on regular daily routes! No one would ever
suspect a thing.
Oh no, I've said too much.
baxtr wrote 1 day ago:
I was amazed how suddenly it stopped being a thing. It was like
one day people were talking about it all the time, and then the
next day it went away completely.
mrguyorama wrote 1 day ago:
It started exactly when the public was getting angry at the
media about killing healthcare CEOs and expressing their joy,
and ended as soon as everyone stopped talking about that.
Which is just conspiratorial thinking. It also ended as soon as
people posted pictures of stars and planes as "evidence" and
insisted that the evidence was still valid because "the aliens
are just appearing as planes". It also ended the moment r/UFO
threads showed up on the front page of reddit and normal people
who thought this MIGHT be something got to see the insane
mental gymnastics of the people insisting we should pay
attention to it.
Mistletoe wrote 1 day ago:
My Mom was super into this just like all the things her TV
tells her to be super into. I asked her today what happened to
them and said she "guessed they fulfilled their purpose and
went back to China". :D
gambiting wrote 18 hours 16 min ago:
Ah, they migrated away for winter.
simpleintheory wrote 1 day ago:
Previously discussed:
- [1] (2018)
- [2] (2013)
- [3] (2011)
URI [1]: https://news.ycombinator.com/item?id=16299441
URI [2]: https://news.ycombinator.com/item?id=5387052
URI [3]: https://news.ycombinator.com/item?id=3274335
giantrobot wrote 1 day ago:
I remember reading about this many years ago but have never been able
to find the story again. So regardless of its veracity, I'm happy to
see it come up.
DIR <- back to front page