User:Doug Coldwell/Sandboxes/Sandbox 26

From Wikipedia, the free encyclopedia

Street light interference, or SLI, is an alleged anomalous phenomenon where a person seems to turn off (or sometimes on) street lights, or outside building security lights, when passing near them. A person believed to have this effect is called a "SLIder" by those who believe in this phenomenon. SLI is described in detail in a free PDF download below called The SLI Effect by one of its believers, Hilary Evans, whom coined the word "SLIder".^[1]

Although street lights sometimes turn off and on by chance (especially when at the end of their life cycle), most believers of SLI claim that it happens to them on a regular basis, more frequently than chance happenings. SLIders propose various explanations ranging from the scientific to the paranormal. Some propose that the radio wave impulses of the brain somehow interfere with street lights. SLI has never been demonstrated to occur in a scientific experiment, and claimed SLIders have been found to be unable to reproduce the effect on demand; they give the explanation that the effect is not within their mental and physical control.^[2] Anecdotes about people's experiences of SLI, however, have been reported in news sources.^[3]

A possible scientific explanation proposed is that SLI is an example of observer bias, encouraged by the pattern of a failing street light. Modern street lights and outside building lighs use high-intensity discharge lamps. These lamps can be started at a relatively low voltage but as they heat up during operation, the internal gas pressure rises and more and more voltage is required to maintain the arc discharge. As a lamp gets older, the maintaining voltage for the arc eventually rises to exceed the voltage provided by the electrical ballast. As the lamp heats to this point, the arc fails and the lamp goes out. Eventually, with the arc extinguished, the lamp cools down again, the gas pressure is reduced, and the ballast can once again cause the arc to strike; this phenomenon is known as cycling. The effect of this is that the lamp glows for a while and then goes out, repeatedly.

Those who actually believe they cause street light interference may then be misled to think the lamp is going out specifically because they are there, but in reality the lamp is turning on and going out repeatedly whether anyone is there or not. The SLIders claim then that it should be scientifically shown that these lights actually are going on and off in regular intervals without their presence. This is where further scientific investigations are needed to determine for sure if it is "just a coincidence" or an actual event caused by the SLIders. Perhaps video recording the SLI event would give the final answer.
The fact that so many witnesses are making claims which seem to involve a SLI effect, that they are doing so in apparent good faith, and doing so independently of one another and without awareness (until they heard of our Project), that the effect may constitute a phenomenon in its own right - these circumstances encourage us to proceed on the basis that SLI, whatever its nature, does indeed occur. We must be prepared to find that the effect is spurious rather than real, and that the SLIders' experiences can be explained without our needing to create a special category for the purpose. History demonstrates that there can be widespread belief in a phenomenon which is nonetheless nothing more than an artifact derived from an erroneous interpretation of witness testimony. However, SLI has a basis in physical reality which is amenable to investigation: SLs are physical objects and the SLI effect, if it exists, must be ultimately a physical process. By its nature, SLI lends itself to methodical observation and controlled testing. At present, no such observation and testing has been carried out, and SLI remains no more than a collection of anecdotal testimony. It is not alone in this: there are many categories of experience whose status is no more strongly based, which is why the claims of ghosts, lake monsters, out-of-body experiences and many more, to be taken seriously as phenomena, continue to be doubted by the skeptical. In such a situation, the creation of a special category - SLI - to house this particular cluster of witness reports is at best a provisional measure.

Neon

Tungsten

Fluorescent

Incandescent

It seems from most reports that there are just certain types of street lights or outside building security lights that are effected. These are mostly of the nature of the mercury vapor and sodium vapor lighting. There are basically no reports on tungsten, incandescent, fluorescent nor neon lighting that is effected by these people. The great majority of these people that have this claimed SLI ability to effect street lights and outside building lights of the mercury vapor and sodium vapor types cause lights to go out, however there are some exceptions to this. Sometimes when the light is out, by walking near these light fixtures these people cause the light to "fire" and flicker ultimately causing the light to come full on. It gives the appearance of an outside "signal" the light fixture received to ignite the inner gases again once the light was off. Rather the ballast then fired the light in a normal manner or the SLIder person ignited the gases is not scientifically known yet in labatory conditions. It could even be that the SLIder affected the ballast itself, but it seems very unlikely since fluorescent lighting is not affected.

• How often have you observed the effect?
• What was the exact date and time of each observation?
• Was the observed effect a lamp or lamps coming on? Going off? Some other effect?
• Did the observed effect occur to just one particular lamp? A string of lamps? Or lamps in several different locations?
• What was the exact location of the lamp or lamps?
• What type of lamp was involved?
  • Sodium (bright yellow).
  • Filament (normal light).
  • Mercury vapour (bright blue/green white light).
  • Fluorescent (diffused white light).
  • Some other type?
  • Not sure / do not know.
• How was the lamp mounted: On a steel lamppost? On a wooden post? Wall mounted? Suspended by wire? Other?
• How did you approach the lamp? On foot? In a vehicle? On a bicycle?

The electrical term called "cycling", that some associate with this phenomonon, is the electrical engineering term more correctly referred to as hertz. One cycle is one hertz. The SLI phenomonon is not a wave function as inferred by "cycling". It also does not have a frequency or oscillation. These are functions that are associated with events consistently happening within certain periods of time (i.e. 1 hz, 60 hz, 870khz, 2.5 Ghz, ultra violet light, infra-red light, microwaves, gamma rays, x-rays). This square wave diagram below demonstrates an "on / off" cycle (a.k.a. hertz). Notice it is consistent with time, meaning it occurs at regular intervals; therefore the term "cycling". The definition of cycle is recurring series. That means it has to accrue on a reqular basis (not random). In the Wikipedia mercury vapor lamp article they speak of End of Life of the lamp mechanism, which explains the function of the Arc Lamp diagram:

At the end of life, mercury-vapor lamps commonly exhibit a phenomenon known as cycling. These lamps can be started at a relatively low voltage but as they heat up during operation, the internal gas pressure within the arc tube rises and more and more voltage is required to maintain the arc discharge. As a lamp gets older, the maintaining voltage for the arc eventually rises to exceed the voltage provided by the electrical ballast. As the lamp heats to this point, the arc fails and the lamp goes out. Eventually, with the arc extinguished, the lamp cools down again, the gas pressure in the arc tube is reduced, and the ballast can once again cause the arc to strike. The effect of this is that the lamp glows for a while and then goes out, repeatedly. More-sophisticated ballast designs detect cycling and give up attempting to start the lamp after a few cycles. If power is removed and reapplied, the ballast will make a new series of startup attempts.

What this means in layman's terms is that the lamp is "weak" because it is older. The actual physical properties of the lamp have changed over time; making it "weak". The electrical ballast can no longer supply the voltage necessary to maintain the arc discharge within the gas bulb itself when it is hot (technically: it is too much resistance). When the lamp cools the resistance decreases and the electrical ballast supplies enough voltage to maintain an arc then. However in this "weak" state (old age) the lamp gets too hot and then cools on a consistent time (i.e. 100 seconds). It can then be seen as "cycling" constantly within this time frame (i.e. 100 seconds +/- 10 seconds). This is entirely different than the Street Light Interference phenomenon, which is quite random (not a consistent cycle). A Lamp that is cycling will present that display (rather someone is there or not) on a regular timed basis.

The videos show this was not the case as is explained further on page 4 of The SLI Effect.

'Street Lamp Interference' (SLI) is an apparent phenomenon, based on claims by many people that they involuntarily, and usually spontaneously, cause street lamps to go out. Generally the effect is intermittent, infrequent and without an immediately discernible sequence of cause and effect.

The lamps stayed off until a SLIder came within range (i.e. 10 feet) to effect the function of the lamp (i.e. either turn it off or turn it on). The lamps in the videos on their own stayed in the one state (either stayed on or stayed off) when the SLIder (one that effects these type lamps) was not present. The lamp fixtures did not display a cycling function on their own going on and off.

All electrical / electronic items follow the basic rules of Ohms Law. If the gas properties internally decrease the resistance, then the lamp turns on (since the ballast then has enought voltage to sustain an arc). If the gas properties internally increase the resistance, then the lamp turns off (since the ballast then does not have enought voltage to sustain an arc).

In mathematical terms, this is written as: :, where I is the current, V is the potential difference, and R is a constant called the resistance.

Using illustrative numbers to show this: 2 amps = 100 Volts / 50 ohms. These number are just illustrative examples to show how Ohm's Law works.

Assuming that the lamp is designed to have the capability of an electric arc if at least 2 amps of current is passing through the gas (mercury vapor), that means then that the resistance can go up to 50 ohms before the lamp extinquishes. At 51 ohms the current is then below the minimum designed to have an electric arc. The resistance increases when the lamp get hot. When it exceeds this threshhold then out goes the lamp. Of course, when the lamp is out, it cools. When the internal gas resistance then decreases (due to cooling) the lamp will arc again at a certain resistance (i.e. 49 ohms). The lamp then is turned on and the resistance starts to increase as the temperature increases. When the resistance gets to 51 ohms (because of the change in the molecular structure of the internal gas) then out goes the lamp. This heating up and cooling is more or less constant. The lamp then can be seen as going on and off in certain time frames (i.e. 100 seconds +/- 10 seconds). This then will occur rather someone is near it or not. In the case of the SLIders the lamp turns off only when that person approaches near the area, as evidenced by the video, and reported in the book The SLI Effect as a general theme. The research book by Hilary Evans (The SLI Effect) explains that the lamp otherwise stays in the one state of either full "on" or stays full "off" with no intervention otherwise by a person switching power or a night sensor detecting the evening.

Any attempt to pinpoint a cause for SLI at this point would be mere speculation without a thorough scientific investigation. The problem with such investigations, as with many forms of psychic phenomena, is that they are very difficult to reproduce in a laboratory. They seem to happen spontaneously without the deliberate intention of the SLIder. In fact, the SLIder, according to some informal tests, are usually unable to create the effect on demand.

A proposed speculation for the effect, if it is a real one, might have something to do with the electronic impulses of the brain. All of our thoughts and movements are the result of electrical impulses that the brain generates. At present it is known that these measurable impulses only have an effect within an individual's body, but supporters of this phenomenon claim it is possible that they could have an effect outside the body, causing interference to electrical equipment.

Ongoing research at the Princeton Engineering Anomalies Research (PEAR) lab is suggesting that the subconscious can indeed affect electronic devices. Subjects are able to influence the random generations of a computer far more than would occur merely by chance. This research - and research being conducted at other laboratories around the world - are beginning to reveal, in scientific terms, the reality of such psychic phenomena as ESP, telekinesis and soon, perhaps, SLI.
'Street Lamp Interference' (SLI) is an apparent phenomenon, based on claims by many people that they involuntarily, and usually spontaneously, cause street lamps to go out. Generally the effect is intermittent, infrequent and without an immediately discernible sequence of cause and effect. SLI deserves study because it gives the appearance of being an anomalous phenomenon in its own right. That is to say, it appears to be an effect which is not consistent with our current knowledge of how people interact with the physical world, and which occurs in specific circumstances. SLI raises many questions, but two fundamental ones are: Does SLI occur? And if so, does it constitute a phenomenon in its own right?

However, if it would be wrong to assume, prematurely, that SLI occurs as claimed, it would be equally wrong to dismiss the claims unless we had good reason to prefer an alternative explanation. If the SLI witnesses are honestly reporting factual events, then SLI constitutes a potentially very revealing process, for it seems to imply interaction between the human mind and external reality. Telekinesis The term psychokinesis was 'introduced by J B Rhine to refer to the direct influence of mind on a physical system without the mediation of any known physical energy' (Thalbourne). It replaced the earlier word telekinesis, which however seems more appropriate in the case of SLI:

• first, because the prefix tele- implies action at a distance, which is a fundamental characteristic of SLI ;
• second, because the prefix psycho- carries connotations of 'psychism' which we should avoid unless it becomes clear that some kind of 'psychic' force is involved in SLI, something which is far from evident. Leaving such hair-splitting aside, it is clear that SLI could have much in common with other phenomena which seem to display an anomalous kinetic effect. That some kind of such interaction occurs in other contexts has long been suspected by open-minded researchers. The 'poltergeist' phenomenon, laboratory PK, and a number of unexplained effects occurring in spontaneous contexts, such as certain UFO observations, also point to something of the sort. (The more obviously relevant are discussed later in this report, see 5.5.) Consequently, study of SLI is important not only in its own right, but because it could help to throw light on these long - but inconclusively - studied phenomena. For SLI has certain characteristics which would make it particularly significant if it occurs:
• it has been reported by people who have no pre-existent model on which to base their testimony. The overwhelming majority of those who have reported their experiences to SLIDE had previously supposed that they had had a one-of-a-kind experience, and have been both relieved and delighted to learn that others have shared similar experiences.
• it involves objects which are too large to be susceptible to the kind of tampering - deliberate cheating or unconscious manipulation - which must be considered a possibility in such paranormal incidents as spoon-bending, apports &c. SLs are large, public objects; and though in theory it would be possible for each of our witnesses to have familiarised themselves with the mechanics of SL operation and tampered with the mechanism prior to experiencing (often in the presence of others) the effect, in practice the probability can be dismissed.
• SLI involves little or no emotional involvement on the part of the witness; consequently, the witness rarely, if ever, has any strong motivation to believe that the SLI effect is real, apart from not wishing to seem a fool for making the claim in the first place. Since SLI provides no evidence for an afterlife or any such motivating theme, and since the ability to perform SLI does not in itself make the witness 'special', the phenomenon is not liable, in anything like the same degree, to the kind of bias which may contaminate testimony in other fields of anomaly research where some kind of 'gift' is supposed to have been conferred on the individual who derives prestige from it in consequence. If SLI can be shown to occur, it would constitute the best evidence hitherto available that the human mind can, under certain circumstances, cause physical events to occur at a distance. It is to be hoped that publication of this preliminary study will be a first step toward implementing research directed to this end.

Contents 1 TESTIMONY: WHAT PEOPLE ARE REPORTING 2 Internal Gases 3 ANALYSING THE TESTIMONY 3.1 When? 3.2 Where? 3.3 Who was present? 4 Meteorological conditions 5 Frequency and Recurrence 6 Technical Aspects 7 Related Anomalous Phenomena 8 Other types of appliance 9 PROVISIONAL CONCLUSIONS 10 Some questions 11 External Links 12 Media 13 References 14 See also 15 External links

[edit] TESTIMONY: WHAT PEOPLE ARE REPORTING

Here are two typical SLI reports:

'Your article has been a huge relief off my mind. I couldn't believe this was a phenomenon that others shared with me. I just thought I was nuts and so did those I told. I had never experienced this problem until about 2 years ago. I first noticed street lights going off when I began taking college classes at nite. Several times when I would turn into my street to come home the street light outside our home went out. I didn't say anything thinking something was wrong with it. Then it began going off when I would step out onto the porch. For a while I thought it was coincidence, then I began noticing lights turning off in other places. I finally said something to my husband one nite when we were driving home and a light went off. He said it was probably the headlights of our car, which made sense to me, and the other times when I was on the porch was coincidental. It continued, and I continued to complain and tell people, just to be made fun of. Then one nite a friend and myself went for a walk by her home, as we walked 4 lights went off as I passed and came back on once I got by. At that point I knew it was me. It continues to happen to me and I continue to try to make others believe me. '(American housewife)

'From 1976 to 1979 I lived in a rented apartment not far from the physics research lab where I worked. Usually I walked home quite late in the evening, and kept on thinking on my computational problems in fluid mechanics. During these evening walks I had to walk along a number of mercury lamps which were switched on at this time. I noticed that about twenty times the lamps went out when I walked under them. The lamps stayed off for the whole night, but next day they operated perfectly again. The lamps were not always the same, and these events were repeated with different lamps on other streets as well. The conditions under which these events took place were always the same: I was concentrating with maximum efforts on my problem, ignoring the outside world completely. At this time I had a mild, sometimes sharp pain at the back of my head, and I was in a very good physical condition. This has never happened when I was even a little bit sick, or I did not concentrate, or did not feel the pain at the back of my head. '(4: Hungarian engineer) This kind of experience has been reported to SLIDE by more than 75 individuals. Considering that the number of people who know of SLIDE's existence must be an infinitesimal percentage of the human race, not to mention other factors such as reluctance to tell others about their experience, or even acknowledge it to themselves, it is reasonable to suppose that those 75+ must be representative of a very substantial population.

This kind of experience has been reported to SLIDE by more than 75 individuals. Considering that the number of people who now of SLIDE's existence must be an infinitesimal percentage of the human race, not to mention other factors such as reluctance to tell others about their experience, or even acknowledge it to themselves, it is reasonable to suppose that those 75+ must be representative of a very substantial population.

The individuals who form that population appear, on the surface, to have very little in common beyond their SLI experience. They come from different walks of life in different countries; they are male or female, young or old. If they are mostly articulate and intelligent, that is probably due simply to the fact that such people are the most likely to read the journals or attend the lectures where SLI is mentioned, and thus learn of SLIDE's existence, and more likely, too, to make the effort to contact it. However diverse SLIders may be, it is reasonable to suppose that there are significant underlying patterns awaiting discovery; it is likely, too, that the quest will take us beyond the SLI experience per se. The SLIDE Project is primarily concerned with a single phenomenon: apparent interference with SLs. However, as we shall see, not only is it appropriate to study SLI in the context of other kinds of reported experience, but SLIders themselves often see their experiences in a wider context. Sometimes this context is an abstract one, in that the individual relates it to his/her mind-set or belief pattern;

but more generally it involves physical experiences of other kinds, most notably interference with other types of ppliance. These are generally - but not invariably - electrical.

Consequently, the scope of research confronting SLIDE comprises:

1. Evaluation of reported instances of SLI: evaluation of their physical circumstances and other factual data related to the technical feats involved: also evaluation of those aspects of SLI experiences which suggest non-physical forces at work: for example, the frequent mention of apparent synchronicity.
2. Study of the SLIders themselves - social and psychological parameters
3. Comparative study of SLI with other relevant anomalous experiences, whether reported by SLIders or by others.

The Project began because I was contacted by individuals who told me of their SLI experiences; this led to my following up occasional letters in the American anomaly periodical INFO Journal, and this in turn led to my setting up a data exchange, to provide some kind of central information point for those interested in the subject. Letters were sent to a handful of publications which would be likely to find the subject interesting. Considerable interest was aroused by a short piece by the respected Texas journalist Dennis Stacy, published in the American popular scientific magazine Omni, in September 1990: this brought in a substantial response, and accounts for the high proportion of American cases in the SLIDE files. Project Slide was created simply as a first step towards defining and assessing the apparent phenomenon. As its name implies, it sets out to be little more than an exchange of information between those who are interested.

Everyone who responded to these announcements received a reply from SLIDE, but not everyone replied to that reply. So we have some 40+ letters from people who were sufficiently interested to write for information in the first instance, but not sufficiently interested to write more fully after learning more. The majority of these said they had experienced SLI, but provided no details; consequently we may regard them as probable SLIders, without however including them in this report. To date, we have received 77 letters containing sufficient detail for them to qualify as a 'case'. In most instances, the information was provided in the initial letter; only a very few responded to a request for additional detail, although a questionnaire was sent to every inquirer. These cases, numbered 1 to 77 in order of receipt, provide the basis for the testimony sections of this report.

One of the most notable features of SLIders' letters is typified by this extract:

I can't tell you how much relief I've felt since hearing others have experienced this sort of "happening" in their lives also.

Another wrote:

I have this problem but had no idea it was widespread enough to be a phenomenon.

It is no exaggeration to say that similar remarks are made in 9 out of 10 of the letters we have received. If SLIders are deluding themselves that they are something special, we would not expect heartfelt expressions of relief that others have had similar experiences and if they are seeking to deceive others, we would not expect them to welcome the menace of scientific investigation of their claims.

It is noteworthy that these expressions of relief are not offered in a highly charged, emotional way. The witness is relieved because we can tell him he is not being ridiculous when he finds his experience puzzling, rather than because his belief-system is threatened or something of that sort. What is at stake is not something as profound as a religious faith or ideology, but simply the individual's own image of himself as a competent observer.

One SLIder speaks for many when he says he regards SLI as something beneficial, but not very important. This gives an additional dimension to the SLIDE project. While we are not in the therapy business, it is nevertheless good to know that SLIDE serves a useful purpose simply by making SLIders aware that they are not alone.

Theoretically, it is possible that every one of our witnesses is deliberately lying; but since each one of them approached us independently, involved him/herself in some effort and expense in making the contact, and has no ostensible motivation apart from a natural and commendable desire to resolve a mystery, deliberate deceit can probably be set aside as an overall explanation, even if it should be true of one or two mentally aberrant individuals. Possible explanations for witness claims of SLI can therefore be limited to three broad categories:

• elusion
• atural phenomenon or mechanical effect
• aranormal process

The effect is spontaneous (with the exception of a few 'control' incidents in which the witness has tested the phenomenon, and which this report will consider separately). The effect is apparently meaningless; it serves no practical purpose, nor does it seem to provide satisfaction for the individual or in any other way serve some kind of psychological purpose.

Theoretically, it is possible that every one of our witnesses is deliberately lying; but since each one of them approached us independently, involved him/herself in some effort and expense in making the contact, and has no ostensible motivation apart from a natural and commendable desire to resolve a mystery, deliberate deceit can probably be set aside as an overall explanation, even if it should be true of one or two mentally aberrant individuals. Possible explanations for witness claims of SLI can therefore be limited to three broad categories:

• delusion
• natural phenomenon or mechanical effect
• paranormal process

A primary question must be: does SLI occur at all, or are the alleged witnesses deluding themselves? Until the phenomenon is scientifically tested, it is not possible to give a decisive answer to this question. We know that widespread delusion has taken place in the past - as with the witchcraft mania of the 16/17th centuries - and continues to occur in our supposedly more enlightened era - as with the currently on-going alien abduction mania: so we must consider the possibility that SLI could be another such shared delusion.

Against this is the fact that SLI has not the 'appeal' of witchcraft or abductions: there is nothing like the same psychological pay-off. Individuals seeking to enhance their reputation for possessing special gifts will not find much to flatter themselves with in SLI, nor do our witnesses reveal any signs of this in their letters or personal contacts:

• if anything, the contrary. All their testimony points to a very matter-of-fact response to a not particularly exciting incident or series of incidents, and to a sincere relief at finding they are not as crazy as their friends have suggested.
• Moreover, the fact that SLI is not an established phenomenon does away with the 'glamour' which attaches to such things as witchcraft or abductions. Here, there is a parallel with the 'old hag' effect reported by Hufford (see bibliography): briefly,

Hufford found that when he gave a label to a category of one-of-a-kind experiences (night terrors) reported to him in the course of his folklore research, this attracted further testimony from persons who had not hitherto reported their experiences because they had no category in which to classify them. There is no evidence to suggest that Hufford's creation and announcement of the category caused people to respond by fabricating imaginary experiences on the lines of his model, as does seem to have been the case in witchcraft and abductions.

Simply, his account made them realise that their own puzzling experience could well have been the sort of thing that he was talking about. This seems to be how the majority of SLI reports are generated. A large proportion of SLI respondents told of their experiences in response to a very short item in a magazine article, where only brief and sketchy information was provided. While we cannot rule out the possibility that each of them was inspired by the item to fantasise a delusion that they themselves had had such an experience, this is not very plausible. In short, while we must keep the possibility before us, it seems highly unlikely that all SLI experiences are delusory.

Overwhelmingly, the initial response from non-experiencers is that SLI is a natural event of some kind. The fact that a mechanical device is involved logically suggests that a mechanical explanation should be looked for, and skeptics (most people new to the phenomenon are immediately and rightly skeptical) generally start by supposing that this process can be accounted for in one or another simple ways.

For example, American investigator Loyd Auerbach, in ESP, hauntings & poltergeists:

Almost certainly what was happening was that headlights of passing cars were being reflected into the photoelectric cells of the lamps (the electric eye that automatically turns streetlights on and off as the sun sets and rises).

Here is a case where an explanation was offered by the witness himself:

I want to describe an occurrence that has gone on for about 9-12 months and would like to see if anyone else has such an experience. For some reason, when I have driven under a specific street light at night, it will go out! Now, this does not happen when I am 50 metres ahead or behind it but when I am exactly underneath it. I have a sunroof in my car, so, when it goes out I can usually look up through the sunroof and see it going out. This has occurred about a dozen times in the last year. I never try to make it go out. About 50% of the time I am not thinking of anything specifically, and am somewhat upset the other 50% of the time.

A fellow correspondent on the bulletin board where it appeared replied:

My friend suggests that since street lights contain light sensors, when you go under them with a sunroof, or a certain angle on the windshield of your car, the reflection of the street light on that surface causes it to shut off because the light sensor thinks it is daylight.

It is then supposed that the misinterpretation on the part of the witness is due to coincidence which strikes the experiencer as significant whereas no such correlation actually occurs. Unquestionably, such explanations should be looked for. However, the effect must be broad enough to cover a very wide range of experiences. For example, the suggestion that headlights on the SLIder's car might have triggered the SL switch is inadequate, because many SLI events occur when the SLIder is not in a car, but walking or cycling. This report outlines the physical task which the SLIder would have to perform in order to achieve SLI:

clearly, the possibility that this is a process which can be expressed in purely physical terms is an option which must be fully explored.

But it is already clear that there is no simple solution.

We must also take into account a further possibility, that some of the cases can be attributed to one of these options, some to another. For example, those cases in which the SLIder is in a vehicle can be attributed to a mechanical effect, those where he is walking to delusion.

Could SLI be another such instance? The consistency of SLI reports, however varied the circumstantial details, argues against any attempt to explain away SLI by separating it into a variety of different misinterpretations, one which applies to otorists, another to pedestrians, and so on.

What seems to be happening in a typical SLI case is this: An individual (we have no cases that suggest multiple activation, though sometimes another individual in the witness's company also produces SLI) is engaged in some unrelated activity when he observes that one or more of the SLs in his vicinity have extinguished.

The effect is apparently meaningless; it serves no practical purpose, nor does it seem to provide satisfaction for the individual or in any other way serve some kind of psychological purpose.

Most SLIders approach their experience with intelligence as well as curiosity, not to speak of wonder and humour. Several of them have made interesting efforts to find a technical basis for what they do:

for example:

It occurred to me that the ones I zap are all on light-sensing switches, and perhaps my energy at certain times for who knows what or why, is the right kind and strength to trick the switch into thinking it is daytime.

In my opinion during such incidents some special, presently not known type of magnetic field is created around the body, which has an effect upon the structure of the materials. Consequently their fundamental roperties are changed temporarily: like their tensile stress, electric conductivity, magnetic momentum, optical properties, etc. The same effects are detected in the case of "metal bending", or similar features are observed sometimes around ball lightnings.

(From a Hungarian physicist. The author is an authority on ball lightning.)

Most commentators, confronted with the SLI phenomenon, look - and rightly - for a straightforward physical explanation. For example, when Robert McMorris of the Omaha World-Herald devoted two or three issues of his regular column to SLI reports in January 1990, he quoted Allen Klostermeyer, manufacturer's representative for Lighting Specialists Inc., who pointed out that when a sodium (amber) bulb nears the end of its useful life, it may go into an off-and-on sequence:

When one of them starts to "die", it requires more voltage. This will cause the lamp to go off temporarily; when it cools down, it will come on again for a while. Eventually it will die completely.

This, it was suggested, is sufficient to explain the SLI effect; what happens is that the witness just happens to be passing such a lamp during its death-throes, and is led by the synchronicity to imagine that he is somehow responsible.

But as the testimony shows, even if we allow the coincidence in place and time, this effect could account for only a small fraction of the reported cases. For one thing, other types of lamp are involved besides sodium lamps. Then again, only a small number of reports describe anything like an SL going off, then on, then off again. And what about when a witness extinguishes a whole batch of SLs: are we to conclude that the whole batch was purchased together, and so shared the same life-span, and such was the perfection of their manufacture, that they all reached their death-point simultaneously?

Yet even if we allow that, there is still the fact that some SLIders extinguish a row of SLs in sequence, each one going out as the witnesses nears it: it is asking too much to suppose that a series of lamps would have been arranged in order of their life-span. Naturally, SLIDE has given considerable thought to the technical aspects of the SLI phenomenon. We have consulted specialists in the field, and received some relevant material; but while we are grateful to these specialists for sharing their knowledge with us, we have to say that no one so far has been able to provide any convincing field explanation.

By far the most useful contribution on this aspect has been made by SLIder Ronald Brown, and what follows is largely a condensed version of his extremely helpful analysis.

Does SLI involve some kind of built-in response: i.e. are SLs designed to respond accidentally to certain environmental factors, and does SLI accidentally duplicate those factors and consequently trigger the response? This is unlikely; it would be ridiculous to design SLs which could be so easily affected. This would lead to inefficient function - i.e. the lamps would frequently be failing to perform their social task - and also be costly both in electricity and in wear-and-tear on the lamp. Does SLI involve interaction with the photo-electric cell which causes the activation of modern street lamps?

This is improbable for a number of reasons:

• The cells are generally mounted on top of the SLs, where they are most receptive to prevailing lighting conditions, but where they would often be out of sightline for SLIders.

• SLs are often controlled as a group; but we rarely if ever have reports of SLs being affected otherwise than individually - that is to say, when multiple effects occur, they occur as a series of individual extinctions, not a single multiple extinction.

• The cell is activated by visible light - its presence or absence. There are no reports of SLIders emitting visible light in any form. Does SLI involve an interruption of the electrical current supply to the lamps? This is improbable because:

• If this were the case, not only would more than one SL be extinguished at a time, but it would be liable to affect area supply, including electrical supply to nearby homes and/or such equipment as traffic lights.

• The supply circuit provides an alternating current of very high electrical potential, unlikely to be overcome by another force of vastly smaller potential.

• Supply circuits are insulated; also, being demand-orientated (i.e. responding to the power requirement at any given time) they possess built-in protection against undue surge or reduction, such as may be involved in SLI.

[edit] Internal Gases

Does SLI act on the internal gas vapour pressure or quality, or on the internal fluorescent materials? This seems improbable because such a process takes time, whereas the SLI effect appears to be spontaneous, or at any rate acts very rapidly.

SLs operate by passing a current through a liquid metal (e.g. mercury etc) which has first to be pre-heated by a starter circuit to form a gas vapour. Once the vapour is warmed to start-up temperature, the general lamp circuit takes over, and so long as it maintains adequate voltage the lamp will function. However, if the voltage should drop below a certain level, the lamp's internal resistance will overcome the circuit and the lamp will cease to function. It will stay off until (usually the following evening) it is re-set or re-activated, along with the regular complete street lamp circuit. Equally, there is an upper limit to the voltage; here again, if the critical level is reached, the circuit will kick-out so as to protect the lamp from the consequences of operating at too high a voltage. This, too, will last until the following evening's re-set or start-up. Normally, the circuit is designed to ensure a supply of current safely within the margin, despite such factors as outside temperature, humidity etc.

In view of the foregoing, the most likely hypothesis would be that SLI operates by affecting the voltage of the current; and it is more likely that it does so by causing a surge rather than a reduction, with the effect of automatically triggering the cut-out. To perform this feat, SLI would have to be an electro-dynamic force, somehow generated within or through the human biological system, and somehow externalised into the neighbouring environment, where it will act on any appliance which happens to be vulnerable. These appliances need not be SLs, of course: and the reports we have of persons affecting computers, supermarket check-outs etc can be seen as providing confirmatory testimony to this. However, there is good reason to think that SLs are particularly sensitive compared with other types of equipment:

this could be because they operate at close to the critical level, or because it is not normally considered necessary to provide them with substantial shielding.

Nor can we conclusively discard the alternative hypothesis, i.e. that SLI operates by causing a reduction in the current. This would be a more complex operation, but is technically feasible. An additional element to be taken into account is the targeting of the individual SL; is this just the one that happens to be closest, or is there some other factor to be taken into account? It should be emphasised that the hypothetical explanation offered here is no more than a 'best bet' arrived at on the basis of what we know so far. It may well be that additional technical information would open up alternative technical explanations. Since at this stage of our inquiry we have no idea what information may be relevant, we have no right to exclude any possible data.

Here are some thought-provoking contributions taken from SLIders' accounts. What at first seems to be a simple case of a defective SL may nevertheless be an instance of SLI, if the SLIder was responsible for the defect:

I drove to a nearby town to attend a meeting. As I was early I parked on the street to wait. There were streetlights lining both sides of the street. I had been sitting in the car for about 10 minutes when the streetlamp on the opposite side of the street (and more than 50 metres away) suddenly went off. I watched in total fascination as it came on again, then popped off again. After about a dozen times I decided to time it. It was not random, but it wasn't cyclical either. The time between going off and coming on seemed to vary from 45 to 55 seconds. There seemed to be no relationship to passing cars, as it very often popped off when there was no car near it. Anyway I left to attend my meeting and when I got out, that streetlamp was still bonkers. Perhaps it was defective, but I suspect it just became defective because I was in the neighborhood.

I would agree that the synchronicity between her arrival and the onset of the defective operation supports her suggestion that something more than chance was operating. To summarise the technical task which is performed by SLI, we can accept that it is fundamentally a physical one - that the modus operandi of SLs lends itself to interference whose effect would be to extinguish the lamp until other factors reversed the process (usually, of course, the following day's switch-on: but in the case of SLs which come on again almost immediately, we have to look for a different process, such as some kind of built-in provision for automatic re-lighting.)

A Street Light, then, may be extinguished by a set of circumstances which should in principle be identifiable:

consequently, it would seem that what SLIders do is somehow to duplicate these circumstances, either by pure chance, or by some deliberate - albeit subconscious - motivation. The next step is to examine the testimony to see if it offers any clues as to what it is that witnesses are doing that somehow duplicates the switchoff process.

[edit] ANALYSING THE TESTIMONY

At this stage SLIDE both enjoys the benefits and suffers from the drawbacks of being a new and unexplored field of research. On the one hand the testimony is relatively uncontaminated, so that we may more readily accept it as an honest account of what happened; but on the other, because SLIders are reporting spontaneous phenomena which often take them by surprise, they ar e not often able to provide much circumstantial detail. If, seeking to understand their experience, they do some investigation, they may observe some additional findings, but this does not necessarily include the information we would like to have.

In order to obtain fuller information, it will be necessary to confront SLIders with a formal questionnaire such as is reproduced at the end of this report. At that stage, however, we shall have to allow for the danger that they may be steered by it into giving an account which conforms to the suggestions implicit in the questions, rather than to what actually happened. At a later stage, when we have a good model of the experience, this can be allowed for; but at this preliminary stage, it is quite an advantage to work from reports which are uncontaminated by any involvement on the part of an investigator, even though this means working from accounts which are sparse in detail.

In fact, the body of testimony we have received is sufficient to provide us with a good deal of useful information regarding the circumstances in which SLI occurs; the technical aspects of the experience; and the kind of person who has the experience. We can also recognise the occurrence of some puzzling effects in connection with SLI experiences, which we must suppose are part of the experience and must be included in any evaluation.

Almost the only constants in a SLI incident are (1) the SL and (2) the SLIder. In every other way, factors vary widely. SLIders may be driving a car, cycling or walking; they may be in a heavily built-up inner city environment or a lightly populated suburban district; the streets may be busy or nearly deserted; and so on.

[edit] When?

By definition, virtually every SLI event occurs after nightfall. However, given that many SLIders also affect other appliances in daytime contexts - eg lights in offices - it would appear that it is not the SLI force but the SL itself which is nocturnal in its habits. There is probably no significance in the fact that SLI events occur in darkness beyond the fact that that is when SL are switched on.

[edit] Where?

Urban streets are the most frequent locale, by definition; but within this heading there are variations,

for example: On busy streets and on side streets.

[edit] Who was present?

Almost every SLIder reports that they produce the effects whether alone or with others. Sometimes they draw attention to it, sometimes not; sometimes their companions notice it, with a variety of responses, usually of disbelief at first, sometimes mockery. Some individual comments:

It often happened when my boyfriend was with me, so at least he didn't think I was crazy. But it happens more often when I'm alone, driving; occasionally when I'm walking at night.

(A cab-driver): The majority of the time I was alone, but occasionally SLI was observed when I was transporting passengers.

:It took a while to convince my wife, but since then she has been with me to witness the lights going out.

Many SLIders are driving at the time, but SLI can occur when driving even if the SLIder is a passenger. Another reports:

It happened when I was walking, driving, or riding my bicycle.

[edit] Meteorological conditions

This is a factor which should be taken into account, in the light of current research into the interaction between psychological processes and the physical environment.

I can't remember ever popping a light in the rain, but then it hardly ever rains in Southern California.

Other SLIders report a possible correlation with cold, damp weather reports

cold and damp; 7 cases

cold and snow 25 case

narrated dates his experience from a thundery evening when meteorological effects were observed.

[edit] Frequency and Recurrence

This is a very variable factor. Few people do it in any way on anything like a regular basis, the SLI being confined to special types of occasion, or to brief periods, or other kinds of intermittence. The following are necessarily only rough categories, derived from those who give any meaningful estimate of frequency:

How often?

:a few dozen in my life

Over how long a period? one brief period only. over a period of years (34 cases)

How frequently?

Do SLI events occur either during a short period, or sporadically over a longer period?

once or twice a year

twice a year

every month or so

a few times a month

one or two per week

virtually every night

at least 140+ in the past year and a half

Many SLIders report a distinct lack of pattern: 'Sometimes it happens once a week, sometimes once a month, and sometimes even once a day' (31) Some specific statements: 'Typically, 3 lights will go off in an hour drive' (16) 'almost a nightly occurrence' (18) 'Sometimes many will go out in one evening' (28) 'I once blew out 7 lights in one weekend at a friend's house. His wife made me replace them!' (44) 'I would put out street lights along an Interstate Hiway exchange, there may have been as many as twenty lights involved at a time' (60)

[edit] Technical Aspects

What kinds of lamp are affected? Most SLIders do not specify what kind of SL they extinguish, either because they do not know, or they would not know one kind of lamp from another anyway. Of those who were able to specify their targets, we have the following indications:

mercury vapour (9 cases)

sodium vapour (yellow) (10 cases)

never with tungsten (4 cases)

never with incandescent bulbs or neon (25 cases)

Number affected in each episode:

• one only on each occasion (4 cases)
• several in succession (6 cases)
• several simultaneously (7 cases)
• Some nights I hit the jackpot - 5 lights and more

Two particularly dramatic cases:

First case (cab-driver): I had been feeling uneasy all day... At around 9pm I drove west along East 4th St: along this street were sodium vapour lamps spaced about 100 feet apart. As I passed, all of the lights on the south side of the street were going out, as I came up to a light, the next three would go out at the same time, then when I came to the fourth, the next three would go out.

Second Case: I was once stopped in a major city by police officers, who wanted to know what I was doing to the city street lights. They had observed that as I turned onto a lighted street, each and every lamp went out as my car reached within 3 metres of it. I looked back and nearly 6 lights or 1½ city blocks of street lamps were darkened. The police searched my entire car and me before allowing me to leave. As I drove away and on down the street, the oncoming street lamps extinguished just before my car reached each pole. I turned off the street and around the block and looked; the streetlamps were still dark, and the police stopped me again and asked me not to drive down that street again until they had the lights checked out. I drove again on that street the opposite direction and once again the far side street lamps went dark as I approached all the way through the city approximately 8 miles. These were electro-vapour type modern street lamps.

The same lamp, or different ones? Some SLIders seem to have individual lamps which they zap more often than others. This is generally due to their location - for example, it may be one they have to pass frequently - so this may not be significant. On the other hand, it could be that some individual lamps are more vulnerable than the average on purely technical grounds. That this last is sometimes the case is suggested by the following account:

At the time I was single, in an unhappy relationship with a woman who lived about an hour away,and without transportation, my car parked dead at the curb and requiring expensive repairs. I worked long hours out of compulsiveness and frustration. It was not a high point in my life. My walk to work took about 35 minutes, and in the darkness on the way home I was almost always thinking intensely. One night I was walking past an apartment building and the yard light turned off. After I had walked past it a few metres, it sputtered back on. I didn't think much of it until the next night, when the same thing happened. Now I began to wonder if perhaps I was doing this somehow. I made a game of it - actually concentrating on turning off the light - and found much to my surprise that I could do it consistently. I found that I couldn't turn off just any light, but that one was a snap. I discounted oncoming car headlights and even observed the light from a distance for a few minutes one night to make sure it wasn't just going on and off at random.

However, before we are tempted to hypothesise that the effect was entirely due to some characteristic of that particular light, consider the sequel:

Then one February night I was walking through the bitter cold and snow through downtown Colorado Springs, feeling quite sorry for myself and actually getting angry. As my frustration with my situation roiled to the surface, the street lights began to go out. Not just one at a time, but five or six at a time. As I walked down the street, more lights went out. I felt filled with excitement, as I looked back at the two city blocks of dim street lights.

What is done to the lights On or off? The great majority of SLIders cause lights to go out, but there are some exceptions:

Sometimes lights that were out, in a row that was mostly lit, would go on. There are at least five other 'on' cases. Just one SLIder has reported that SL will either extinguish completely or dim to the point of practically no light. How rapid are the effects? Few SLIders have commented on this aspect, and the impression given is that the effect is instantaneous, insofar, that is, that we acknowledge there is anything for it to be instantaneous with. So when we have a statement like this: It is a matter of seconds before the street light goes on or off we must suppose there is some definite moment from which the witness is measuring the time lapse.

What makes this factor particularly intriguing is that the emotional state is not always the same. One SLIder says

it seemed to be tied to strong emotions (positive or negative).

Among specific emotions identified by SLIders are:

feeling agitated, aggravated, upset

When I get aggravated, fluorescent lights go out over my head, or over the heads of those with whom I am upset.

feeling angry

repressing anger

feeling anxious, uneasy

concentrating

feeling depressed

feeling elated

SLI mostly happens when I am elated, but being upset causes it as well.

feeling emotionally shut-down

feeling excited

feeling fed-up

feeling happy

high energy level

intensity of feeling

This seems related to intensity of feeling that is for some reason not being expressed, or expressed fully.

feeling irritated but note:

I do notice that I usually have to be feeling some irritation for household lights and appliances to malfunction, but streetlights go off around me without me being really annoyed.

nothing on my mind

feeling relaxed

feeling serene

sexual activity

feeling stressed

[edit] Related Anomalous Phenomena

Study of SLI must include not only study of the SLI experience per se, and of the SLIders who experience it, but also other kinds of experience reported by SLIders, and other phenomena, occurring independently from SLI, but which appear to offer sufficiently similar characteristics for the question to be raised, whether the same or similar forces may be involved.

Other electrical appliances affected by SLIders. A very high percentage of SLIders report similar effects with other types of lamp:

I notice when I get aggravated, fluorescent lights go out over my head, or over the heads of those with whom I am upset.

very frequently, lights in my home or friends homes.

Here are two SLIders' experiences with domestic lights:

I first noticed this phenomenon when I moved to New York City. I lived there for five years, in 3 different apartments, and my roommates always referred to me as "the fuse blower". When I would come home from work, usually irritated by a crowded subway ride, the first light I would put on would "pop" and be burned out. Also other appliances wouldn't turn "on" when I touched them, and someone else would have to turn them on.

I worked in an office then, and one day the woman in the office next to mine called me over and really made me angry. Suddenly all the lights in her office went off, and the switchplate was too hot to touch. The maintenance man was baffled because she was on the same circuit as the rest of the offices, and only hers went out. I told her that I did it and she never bothered me again!

Once or twice a year, year after year, light bulbs - some virtually brand-new - have come on briefly and then burned out as soon as I flipped on the controlling wallswitch. In virtually all of these instances such anomalies as power surges or mechanical malfunctions could easily be eliminated. Moreover, in the majority of instances I knew, unmistakably, an instant before I touched the switch, that the bulb would burn out. Before my fingers touched the switch I knew, clearly, what was about to happen. At no time was my anticipation wrong.

Other SLIders do domestic lights, while others specifically observe that they do not affect anything but streetlamps: I do not affect normal household bulbs or anything other than streetlamps.

[edit] Other types of appliance

Computers are another favourite target:

There have been several times when I knew my computer was going to die and need repairs - just before it died and showed no outward symptoms: did I sense it or cause it?

Several others affect computers and word-processors. Intriguingly, the effects are not always destructive. One SLIder, an engineer with a pacemaker manufacturer, reports:

I have the experience of turning off street lamps frequently. I also have a kind of "healing" effect on computers in our research department. I am frequently involved in helping colleagues with high-performance computer installations. When they have trouble and ask me to come by and help, the problem almost always disappears when I handle the machine - I've acquired a somewhat humorous reputation over it !

Other specified items include:

aircraft electrics

alarms

business pager

camera

car electrics

car alternator (I am now on the eighth)

cash registers

clocks

compass

copy machines

dice

dowsing rods

floodlights

gambling machines

iron

lift (elevator)

lottery machines

machinery

microphone system

radio

railway crossing

store safe

telephone

television

typewriter

video games

watches (I also kill watches)

[edit] PROVISIONAL CONCLUSIONS

Insofar as a meaningful model can be constructed on the basis of anecdotal testimony, the body of case histories so far accumulated does seem to constitute a case for regarding SLI as a phenomenon in its own right. Like so many other anomalous phenomena, its existence must remain in question until some conclusive evidence is forthcoming; but the apparent evidence is persuasive. Moreover, since this report is based on reports supplied only by the tiny section of the population who are aware of SLIDE's existence, we must presume that for every case cited here there are hundreds if not thousands more unknown to us.

It therefore seems in order to construct a provisional model for the phenomenon, to be used as a working hypothesis which we can test, as a way of establishing, first, the existence of the phenomenon, and then its nature.

A skeptic could reasonably argue that it is somewhat premature to put forward conjectures as to what the SLI effect may be when we are not yet sure of its existence:

it may appear as academic as to debate the mode of propulsion of extraterrestrial flying saucers when it is by no means certain that flying saucers exist. But such speculation, by requiring us to confront the minutiae of the matter, even when we do not know the nature of the matter, can help us to think scientifically about the problems it raises.

More importantly, as with flying saucers, there is one very good reason why we should proceed as though the phenomenon exists: and that is the fact that a good many people are reporting the experience as though an actual phenomenon is involved. Certainly, people can be mistaken or deluded, and we must keep this possibility in mind. But that, too, is something which would have to be proved before we would accept it: and until such time as it is proved, it is right to respect the testimony of people who claim these experiences at first hand.

Consequently, it is justifiable to proceed to construct a hypothesis on the basis of their testimony, with the implicit caveat that our speculations are contingent on the good faith and accurate reporting of those who supplied the testimony.

[edit] Some questions

Are SLIders a special kind of person, or ordinary people who are in a special state?

In a sense, both. To perform SLI, it seems that a person must be in a particular state: but some people go more easily into that state than others,
so it can be said that there are SLI-prone people.

Are street lamps chosen as targets, or is this chance?

A case could be made on psychological grounds for seeing SL as somehow symbolic, and therefore a fit choice of target. For example, a person passing through a black emotional phase might want to cause SLI as a public declaration that to him the lights of his life have gone out. Or extinguishing street light could be an expression of exuberance just as young men who have had too much to drink are liable to smash windows, etc.

Plausible as such explanations might be in some cases, I personally have always the uneasy feeling with regard to symbols that with a little manipulation almost anything can be used to symbolise anything else. So I personally do not feel very enthusiastic about this kind of explanation.

Additionally, there is the fact that our SLIders seem to be in a wide variety of emotional states; it would be strange if they all concurred in thinking that SL somehow symbolised their varying states. Nevertheless, this approach should not be dismissed out of hand until we are more sure of our way. The fact that so many SLIders affect other types of appliance seems to suggest that the force which extinguishes SLs can also be deployed in other directions. Should we conclude that those who affect only SL have the power only feebly, those who affect other appliances have it more strongly? Possibly; but it is also possible that they have the force in a different way. The explanation may be simpler than any of this; it may be that SL are, by their physical nature, more sensitive to the force than any other kind of appliance.

People in an appropriate mental state are able to affect the operation of street lamps, at a distance, generally spontaneously rather than deliberately, as a consequence of their unconscious mental activity.

In addition, we can offer the following findings as supported by the testimony:

• While there is no known limit to the range of the SLI effect, it seems generally to occur in fairly close proximity to the individual - say under 10 metres (though we must recognise isolated examples of SLIders who claim to deploy the force over greater distances). The SLIder seems always to be in sight of the SL - we have no instances of SL being affected out of sight, but of course this would be difficult to establish.

• There is no evidence to show whether the force which affects the street light is a force field or a directed beam. But whatever its nature, it seems sensible to conclude that it emanates from the SLIder to the street light in a straightforward physical manner; there is no evidence, for example, to suggest that the force detaches itself from the SLIder and travels autonomously to the target.

[edit] External Links

So many witnesses are making claims to the Street Light Interference phenomenon and doing so in good faith with no particular ulterior motive that it inspires ongoing studies and research by many entities. Here are some websites and blogs addressing SLI that have been ongoing since year 2000.

• EEL's Street Lamp Interference Information Site
• Do Highway Lights Turn Off Around You Too
• Port Stephens Paranormal Investigations
• SLIders & the Streetlight Phenomenon
• About:Paranormal Phenomena

• The Electric People Project
• SLIders Phenomenon
• O.K. I'm a SLIder

• Its Electrifying
• 32 Degrees
• Cool

[edit] Media

These videos illustrate situations in which Street Llght Interference occur:

[edit] References

• Waymouth, John (1971). Electric Discharge Lamps. Cambridge MA: The MIT Public Press. ISBN 0-262-23048-8. 

• Street Light Interference article published in scientific magazine Omni, September 1990 journalist Dennis Stacy,
• Street Light Interference articles reported by Robert McMorris Omaha World-Herald several issues January 1990.
• The Paranormal Investigator's Handbook by Valerie Hope. Publisher by Sterling Co. 1999. ISBN-10:1855857030.

1. ^ The SLI Effect, by Hilary Evans. ISBN 0-9521311-0-2.
2. ^ SLIders & the Streetlight Phenomenon, in About.com's "Paranormal Phenomena", by Stephen Wagner.
3. ^ CNN reports on the effects of a claimed SLIder with interview in a video clip of this person making such a claim.

[edit] See also

• Arc lamp
• Energy level
• Sodium vapor lamp
• Mercury-vapor lamp
• Gas-discharge lamp
• High-intensity discharge lamp
• Timeline of lighting technology
• History of street lighting in the United States

[edit] External links

• The Mystery of Blinking Street Lights Washington Post (Nov 17, 2002)
• SLI in the James Randi Educational Foundation's commentary archives
• ASSAP (a paranormal organization)'s view on how SLI should be investigated