Forgot your password?
typodupeerror
Networking Wireless Networking Science

9th Grade Science Experiment: Garden Cress Won't Germinate Near Routers 327

Posted by Soulskill
from the are-the-routers-in-the-freezer dept.
New submitter SessionExpired writes "Five 9th graders from Denmark have shown that garden cress won't germinate when placed near a router (Google Translation of Danish original). Article text is in Danish, but the pictures illustrate their results. The exact mechanism is still unknown (Danish original), but experts have shown interest in reproducing the experiment."
This discussion has been archived. No new comments can be posted.

9th Grade Science Experiment: Garden Cress Won't Germinate Near Routers

Comments Filter:
  • by Gothmolly (148874) on Friday May 17, 2013 @04:23PM (#43756845)

    Thanks, Editor-dot, for not reviewing TFS. This was an experiment to test EM radition, its nothing to do with 'routers'. Believe it or not, there are things which are 'routers' that are not supplied by your ISP when you sign up for home broadband.

  • by pspahn (1175617) on Friday May 17, 2013 @04:32PM (#43756973)

    If I were them, I would find a way to measure the internal temperature of the cress.

    At least read TFS.

    ..garden cress won't germinate when placed near a router

    So, you see, there is actually no cress for them to measure. It never germinated.

  • Re:Bit misleading (Score:4, Informative)

    by Scutter (18425) on Friday May 17, 2013 @04:44PM (#43757113) Journal

    The point is that they are using confusing and inconsistent terminology to report on the parameters of a scientific study. Using imprecise language muddies the results and makes them hard to reproduce, or even to draw a conclusion of your own.

  • by Anonymous Coward on Friday May 17, 2013 @05:08PM (#43757471)

    They're using 2.4GHz wifi routers. 3G and LTE was not chosen because of data cost.
    The rooms are all locked, so only the teacher and the 5 pupils have access.
    They've done the tests twice with the same results.
    They've controlled temperature, water amount, sun radiation from windows and more factors, to control bias.

    The danish newspaper Ingeniøren (The Engineer) has the teacher Kim Horsevad explain in detail in the comments on their article on the subject: http://ing.dk/artikel/folkeskoleelever-vaekker-forsker-opsigt-mobilstraaling-forhindrer-karse-i-spire-158867#comment-529110

    His comment is REALLY long, so some other dane will have to translate if Google Translate doesn't cut it ;)

  • Re:No reproduction (Score:2, Informative)

    by Anonymous Coward on Friday May 17, 2013 @05:16PM (#43757567)

    For anyone who actually wants to reproduce the experiment, a teacher from Hjallerup posted a detailed description of the experiment setup [ing.dk] in the comments of the second FA. It's in Danish, but Google Translate should be able to make some sense of it.

    At the very least, it seems to have been done a lot more thoroughly that I had first suspected. I'm still sceptical that the results will be consistently replicated, but the experiment as described is of high enough standard to warrant an attempt.

  • Re:No reproduction (Score:5, Informative)

    by tlhIngan (30335) <slashdot AT worf DOT net> on Friday May 17, 2013 @06:05PM (#43758031)

    The radio, and associated amplifiers, will generate the majority of the heat. Just look how much longer a cell phone will operate if you disable wireless. One must also take into consideration that wireless routers operate at higher power levels.

    Actually, cellphones are higher powered - I believe they top out at between 0.5-1W max transmit power. Your wireless router is typically anywhere from under 50mW to 100mW, though it's possible to get "long range" ones that do 250mW.

    Of course, a cellphone dynamically adjusts its power - in urban areas, it typically is close enough to a cell tower that it can crank the transmit power way down. This, of course, is to save battery (RF level amplifiers aren't efficient at all - they waste a lot of power). If you live in a poorly covered area, you'll note your battery life is a lot lower as a result of having to crank up the power to maintain the link.

    CDMA phones are interesting - the amount of power they use is proportional to usage as the more phones using it, the lower the SNR. You've hit the limit when everyone's transmitting at max power and the SNR is too low for successful correlation.

  • by SessionExpired (642030) on Friday May 17, 2013 @06:40PM (#43758297)

    Since I submitted the story, the full report has been made public [scribd.com], and the biology teacher involved in the experiment has commented on various details [ing.dk].

    Based on information from these two links, I'll try to answer your questions (my translations).

    -Wifi and GSM are on different bands so why speculate cell phones could also have the same effect?

    The report doesn't explain this. It goes from "We want to study the effects of radiation from cell phones" in one paragraph to "we'll be doing this by [...] cress seeds placed near Wifi hotspots or not" a bit later. The teacher notes "For newer 3G or LTE connections, the difference [compared to AP frequencies] is minimal".

    -Did they repeat the experiment using the same plant seed type more than once?

    They used seeds from several bags, mixed together and then divided in 12 lots.

    -Did they note the temperature, humidity and sunlight available in each room at regular intervals or used any data logging equipment?

    Not according to the report. From the teacher: "windows of similar size and both facing south" and "computer controlled temperature (18 deg. Celsius)".

    -What kind of rooms, and were they in the same home? Were they the students bedrooms or what?

    The report doesn't say. From the teacher: "Access control: only a select group of people can access the 'depotrum' used for the experiment". 'Depotrum' could mean a room used by janitors, to keep books etc.

    -Were both testbeds receiving the same amount of sunlight for the same amount of time?

    The report says "both windowsills [?, the lowest part of the window frame, facing into the room] were facing south, so we could ensure that all plates were receiving the same amount of sunlight". See note from teacher above.

    -Did they try other plant seeds? Or buy the same plant seeds but from different vendors to compare?

    No other plant seeds were tested. It is not clear from report or teacher if the bags mentioned above were from the same vendor.

    -Did they try to repeat the experiment with the router off to isolate the possibility the rooms environments played a role?

    The report doesn't mention this. According to the teacher, they did run the experiment twice, not to test differences between the rooms, but to test if network traffic played any role. The first run was made with the AP only announcing ESSID, the second run had the laptops pinging each other [constantly, I assume].

    They used roline wireless routers [bn-elektronik.dk] for the experiment.

  • Re:Need a control. (Score:4, Informative)

    by Khyber (864651) <techkitsune@gmail.com> on Friday May 17, 2013 @07:40PM (#43758729) Homepage Journal

    No, heat is NOT EVEN CLOSE to being a viable cause. Room is controlled and regulated. Cress has quite a nice wide range of germination temperatures.

Make sure your code does nothing gracefully.

Working...