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21 Grams

  1. Mar 27, 2006 #1
    It's sayd that when one dies, the body loses 21 grams of it's weight.

    Has this been proved???? i think it's just a false myth, very easy to verify.
     
  2. jcsd
  3. Mar 27, 2006 #2

    Math Is Hard

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    from snopes.com
    http://www.snopes.com/religion/soulweight.asp
     
  4. Mar 27, 2006 #3

    SGT

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    Dr Duncan MacDougall claims to have measured the weight of the soul in 1907. Believe it if you want.
    edited to add:
    Math is Hard beat me on that.
     
  5. Mar 27, 2006 #4

    Math Is Hard

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    Ah! A fellow snopes fan!!
     
  6. Mar 27, 2006 #5
    This experiment should be done again, but the bed must be over a scale, and in a perfectly sealed room, the room must be mesured also, so if the "21 grams soul" escapes from the body then the Room should weight the same and the sould would be trapped in the room, but if the room loss 21 grams then it's a even more interesting result.
     
  7. Mar 27, 2006 #6
    Seems to me if the body loses weight, the soul must have been on it's way down when it left the body. They should try this on some good people.
     
  8. Mar 27, 2006 #7
    http://www.google.com/search?q=21+grams*c^2+/+10^14+Hz

    21 grams * c^2 = 1.88738588 × 10^15 joules

    http://www.google.com/search?q=21+grams*c^2+/+(h+*+10^14+Hz)

    21 grams*c^2 / (h * 10^14 Hz) = 2.84842515 × 10^34

    So about 10^34 photons of infrared frequency would have to be emitted for there to be a mass decrease of 21 grams (or the equivalent amount of energy in other frequencies).

    For perspective, a nickel emits 1.82 x 10^19 photons per second (note that this is with an influx of energy).

    http://www.google.com/search?hl=en&lr=&q="photons+per+second"
     
    Last edited: Mar 27, 2006
  9. Mar 27, 2006 #8

    Ivan Seeking

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    Something else, IIRC the original test on this included an absurd number of significant figures - well beyond the hardware available at the time. This strongly suggests that he didn't know what he was doing.
     
  10. Mar 27, 2006 #9
    When he said that those 21 grames where the weight of the human sole he seemend to just way perosn body right after he died.He didn't seem like he never did any scientfic experment to find out way when someone dies they 21 grames he just asumend that those 21 grames where a persons sole.
     
  11. Mar 30, 2006 #10
    The mechanics of a soul's weight

    Is it 21 grams for everyone, or do heavier people have heavier souls?

    And I wonder, if I was a really, really good person - like I ate all my veggies and did all my homework before bed, and only watched wholesome television, if any - would my soul be heavier because it was better, or lighter because it was less burdened by the massive quantity of sins and indiscretions that I actually have. o:)
     
  12. Mar 30, 2006 #11

    Pengwuino

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    Doesn't your body lose weight though as gases are emitted and other bodily functions continue for a little while?

    And come on Ivan, we all know the weight of your average human is 60.18749137489072134163249871329812347632141431241 kg
     
  13. Mar 30, 2006 #12
    One of the most depressing movies ever
     
  14. Mar 30, 2006 #13

    PerennialII

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    ....... which made it an excellent piece of "entertainment" :biggrin: . Isn't the argument that the loss in weight is essentially a step function at the moment of death, making conservation related counter arguments bit difficult? Debunking the accuracy of the experimental setup for weight would be interesting, is this particular result(s) just an offshoot, outlier, flap of a butterfly or what....
     
  15. Mar 31, 2006 #14
    Maybe the 21 grams weight reduction is due to the stopping of inertia load when the heart stops beating. As the heart beats it creates a minute inertia load on the body, albeit small, but it is effectively constant creating a minute effective weight increase of the body. When the heart stops beating the delta weight increase due to heart beating stops thus reducing the weight of the body by 21 grams. Just a theory.
     
  16. Apr 2, 2006 #15

    Moonbear

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    :rofl: Good point!

    I would think the body would lose a bit more than 21 grams at death, considering there is usually a relaxation of the sphincter muscles that control excretory function. :rolleyes:

    I would also find it really hard to believe that in 1911 a balance (scale) existed that would permit accurate weight measurements on a range of a gram all the way up to over 100 kg. I'm not even sure such a balance exists today...that's a pretty wide range to remain accurate over.
     
  17. Apr 2, 2006 #16

    Ivan Seeking

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    I thought about that but it would probably still be on the table used for weighing, but...

    even worse, Pengwuino wasn't kidding. The guy did cite a number like 60.18749137489072134163249871329812347632141431241 kg. :rolleyes:
     
  18. Apr 2, 2006 #17

    Moonbear

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    I should read all the links before replying. The one SGT posted explains the methodology in more detail. It sounds like this guy just had a scale that drifted, plus he wasn't even measuring accurately...it was a beam balance no less! Those are notoriously subject to observer error (is the beam really in the same place every time?)

    This quote highlights the imprecision of the measurements:
    :rofl:

    I wonder if they checked for any mice scurrying around the bedside. A small, adult mouse could weigh about 20-25 grams. (By the way, he was recording his measurements in ounces, with a scale he claimed was accurate to 0.2 oz, according to the snopes article, which is about 5.6 g, but it included not only the weight of the person, but the bed as well, so while it may have had weights down to 0.2 oz on it, I HIGHLY doubt it was really calibrated for accuracy to that scale.)
     
  19. May 11, 2006 #18

    Art

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    Guess we need to repeat the experiment using modern technology. Now who here would like to volunteer to sacrifice themselves to further human knowledge. :biggrin:
     
  20. May 12, 2006 #19
    I think we can find some volunteer's here
     
  21. Jan 2, 2009 #20
    In My Opinion the soul cannot possibly be weighed . the reason for this is simple . are we all forgetting sir isaac Newton and what he taught us all about gravity (gravity determines weight) IE an object has to respond to gravity for it to be weighed therefor it needs Mass . ask yourself does a soul have Mass ? there you will find the answer
     
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