Electrostatic Wall: David Swenson's 3M Anomaly

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    Electrostatic Wall
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Discussion Overview

The discussion centers around an anomaly described by David Swenson of 3M Corporation, where workers reported encountering an "invisible wall" created by a fast-moving sheet of electrically charged polypropylene film in a factory. The phenomenon raises questions about electrostatics, plasma dynamics, and potential technological applications.

Discussion Character

  • Exploratory, Debate/contested, Technical explanation

Main Points Raised

  • Some participants express skepticism about the credibility of the claims regarding the "invisible wall," with one participant labeling it as "total bogus."
  • Others mention a telecommunications company, Telstra, advertising technology that suggests the ability to create a similar effect, raising questions about the feasibility and scientific basis of such claims.
  • One participant proposes that the phenomenon may be related to plasma dynamics rather than electrodynamics and raises concerns about the health effects of long-term exposure to ionized air.
  • A participant introduces the concept of a plasma window, drawing parallels between its function and the fictional force fields in Star Trek, suggesting a historical context for the discussion.
  • Another participant suggests that the "invisible wall" effect could be explained by electrostatic repulsion, where individuals become similarly charged and are thus repelled from the charged sheet.
  • One participant provides details about the static charge developed when the plastic sheet is unrolled, noting high voltage readings and proposing a theory involving induced charges in the air beneath the sheet.
  • A later reply mentions that the phenomenon was observed to be affected by humidity, which could cancel the electrostatic effects.

Areas of Agreement / Disagreement

Participants generally express skepticism about the claims and the feasibility of the technology described, with multiple competing views on the underlying physics and implications of the phenomenon. The discussion remains unresolved regarding the validity of the claims and the potential for similar technologies.

Contextual Notes

There are limitations in understanding the phenomenon due to missing assumptions about the conditions under which the "invisible wall" was observed, as well as the dependence on definitions of electrostatic and plasma dynamics. The discussion also highlights unresolved mathematical and physical principles related to the observed effects.

wolram
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I came across this by accident.

http://amasci.com/weird/unusual/e-wall.html.

David Swenson of 3M Corporation describes an anomaly where workers encountered a strange "invisible wall" in the area under a fast-moving sheet of electrically charged polypropelene film in a factory. This "invisible wall" was strong enough to prevent humans from passing through. A person near this "wall" was unable to turn, and so had to walk backwards to retreat from it.
 
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At a glance this Bill Beaty [the source] seems to be a bit fringe but okay... not sure yet. Still the claim itself sounds total bogus to me.
 
Nope, I come from Australia and our biggest telecommunications company Telstra (the old telecom) is running adds that suggest they have the tech to do such a thing and will be selling it within ten years. I know it sounds like complete garbage to suggest it's possible and I was equally surprised to see a credible company like Telstra advertising such a futuristic idea but they are and I don't know what they think they have but it shows a woman walking through a field that according to the add detects your person as you approach and allows you to pass through while stopping unwanted trespassers from entering. They also say that they will be providing this service in the future? Sounds like science fiction and as I said I was surprised they said or implied it would be possible but they did and I would like to here if anyone has got any info on the matter as I know a fair bit about QFT and this sounds like crap but surely Telstra aren't scientifically challenged. It scares me to think what tech really big business may own and don't release to the likes of us until it's commercially viable.
 
David Burke said:
Nope, I come from Australia and our biggest telecommunications company Telstra (the old telecom) is running adds that suggest they have the tech to do such a thing and will be selling it within ten years. I know it sounds like complete garbage to suggest it's possible and I was equally surprised to see a credible company like Telstra advertising such a futuristic idea but they are and I don't know what they think they have but it shows a woman walking through a field that according to the add detects your person as you approach and allows you to pass through while stopping unwanted trespassers from entering. They also say that they will be providing this service in the future? Sounds like science fiction and as I said I was surprised they said or implied it would be possible but they did and I would like to here if anyone has got any info on the matter as I know a fair bit about QFT and this sounds like crap but surely Telstra aren't scientifically challenged. It scares me to think what tech really big business may own and don't release to the likes of us until it's commercially viable.

It sure sounds (futuristic) i know nothing about Telstra, but i guess they have little to gain from crackpot claims.
 
Hmm...it would seem to me that this is more a problem of plasma dynamics than it is of electrodynamics. Of course, if Telstra really is marketing something of this nature, I would think that long-term exposure is unhealthy, simply because the production of ionized air will create a ton of ozone along with it.
 
That is interesting, Ivan. And I did chuckle at this:

"..Curiously, the plasma window functions in a way which very superficially resembles the force field in the Star Trek TV series. For example, there is an area on the Enterprise (the Shuttle Bay) from which shuttle crafts leave for flights into space. At the edge of that area there is a force field (with a bluish glow at its perimeter) which separates the atmosphere (air) on the Enterprise and the vacuum (space) outside. Similarly, in the plasma window, a plasma (which is an ionized gas confined by electric and magnetic fields) separates air from a vacuum by preventing the air from rushing into the vacuum. A variety of gases can be used to operate this window. When argon is used, the window color is blue, similar to that shown in Star Trek..."

I was rather surprised when I saw the date, 1998. I thought this was something brand new. The original post about "the wall" is quite old too, 1995. Interesting.
 
David Burke said:
Nope, I come from Australia and our biggest telecommunications company Telstra (the old telecom) is running adds that suggest they have the tech to do such a thing and will be selling it within ten years.

That Telstra ad is about network security.

This description is for those who haven't seen the ad: The ad basically shows a woman walking along the footpath in a city. She then turns and walks through a glass panel (as if it didn't exist) into a building. Then other people try to enter through the same panel, but alas, they hit the glass and are not granted passage.

It says something along the lines of "network security so advanced only you can pass through". Obviously the ad is meant metaphorically and not literally. I highly doubt a telecommunications company will ever even try to research a technology so abstract, let alone questionable in terms of the physics.
 
wolram said:
I came across this by accident.

http://amasci.com/weird/unusual/e-wall.html.

David Swenson of 3M Corporation describes an anomaly where workers encountered a strange "invisible wall" in the area under a fast-moving sheet of electrically charged polypropelene film in a factory. This "invisible wall" was strong enough to prevent humans from passing through. A person near this "wall" was unable to turn, and so had to walk backwards to retreat from it.

I think all that's probably happening here is that, as the person approaches the highly charged sheet of plastic they become similarly charged. Like charges repell and they are prevented from approaching closer by simple electrostatic repulsion.
 
  • #10
Isnt it possible though?
 
  • #11
There is a huge static charge developed when plastic sheet is unrolled. It is usually a hazard for these companies. While this "wall" was active a guys static meter pegged at 200 KV from 50 ft from the spools. He estimated the voltage to be in the megavolt range.

The wall was perpendicular to the moving sheet. There is a rough drawing of the arrangement somewhere on the net.

The final prevailing theory was that the moving charged sheet induced a rotating region of highly charged air between the sheet and the concrete. Humidity effectivly canceled the effect. Due to the action of static charge moving in this way it tends to center on the sheet, and in the air beneath the sheet. This was explained as the moving charges behaving like similar current flows in wires. The current flows are attracted together by their magnetic field.

Crazy but true. The plant owner said he didn't know wether to, "fix it or sell tickets."
They fixed it.