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Dead Weight/Live Weight

  1. Aug 15, 2011 #1
    My cat died recently and both my daughter and I were amazed at how much heavier he was dead than alive. I have read the posts on this website about live "dead weight" (The boy who found his sleeping sister to be much heavier to carry than when she was awake.) But the answer does not seem adequate. Does anyone know of anyone who has actually experimented with weighing a living body and then weighing the same body after death--whether human or animal? Thanks.
  2. jcsd
  3. Aug 15, 2011 #2


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    A dead body will not weigh more than a live one. Let's just get that out of the way.

    The difference will be in carrying a body that is
    a] willing, and
    b] has muscle tone to keep its shape
    versus a body that is neither.

    Try picking up a 30 kg box with handles. Tough it may be - until you try to pick up a 30kg bag of dry cement mix - which is virtually impossible.
  4. Aug 16, 2011 #3
    Thanks for the reply Mr. Smarty Pants. However, I am still not convinced by your arguments.
    a) my cat was extremely independent and hated being picked up and when I occasionally did he struggled in a most UNwilling manner. So presumeably according to your argument that would have made him heavier. Nevertheless, that was the weight I had to go by. 9 pounds on the scale at the vets.
    b) while alive he certainly did have muscle tone to keep his shape, however, shortly after death--the time which I am curious about--during which he felt so VERY much heavier--his body kept its shape even better--as rigor mortis had set in.
    So your analogy of his dead weight to a loose bag of dry cement is not a parallel.
    However, I am still willing to be convinced. And I return to my original question--do you, or anyone else, know of any actual scientific research in which a body--human or animal--was weighed just before death and again after death--and I will add the proviso that it should be when rigor mortis has set in. And what was the result.
    Etymologically the phrase can be traced as far back as 1650 (http://www.etymonline.com/index.php?search=dead+weight). So I would assume that since at least then people were noticing that dead bodies felt heavier than live ones. I I still need to be convinced by further arguments than the ones you have presented thus far that it is simply a matter of perception and not an actual weight change.
  5. Aug 16, 2011 #4


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    Well I need to be convinced that there is no teapot orbiting Jupiter.

    See, the best argument against a teapot orbiting Jupiter is that there is simply no conceivable way it could be true.

    Same with your case.

    You may believe it to be true, but until you put forth a hypothesis that's plausible, no rational person has any reason to spend any time on it.

    Simply put, by far the best explanation is one of subjective and very poor comparison of weights under very divergent circumstances and time intervals. It explains every aspect of the mystery very neatly, and is very well supported by a huge preponderance of evidence about human perception and estimation.

    What you linked to is simply a definition of the term. There is nothing in there about dead bodies weighing more than live ones.

    To sum, you have neither
    1] a hypothesis as to how it could be true
    2] a shred of evidence that it is true that's been tested under controlled conditions
    while what you do have is
    3] a hugely plausible and verified counter-theory.

    Welcome to the scientific method. :smile:
    Last edited: Aug 16, 2011
  6. Aug 16, 2011 #5
    I take exception to your argument that because you --or even most people-- cannot conceive of something as possibly being true--that that constitutes PROOF that it cannot be true! My conjecture is that a dead body might possibly weigh more than a live one. It may not--but your argument that it cannot be true is not rational.
    For example, most people's RESPONSE to the idea that a single object can actually be in two different places at the same time--would probably be the same as your response to me above: "there is simply no conceivable way it could be true." Yet quantum physicists have done EXACTLY that in the laboratory--produced an object being in two places at once.
    Just because people could not conceive of the world being anything other than flat, did not make that true either.
    So again--I AM willing to be convinced, but it will take better arguments than you have offered so far. Also, please read my words more carefully. I did not say I believed it was true that a dead body in a state of rigor mortis weighs more than a live one. I just said it SEEMS so. And I am requesting information about research on the subject.
    You asked for a hypothesis. So how about this one:
    A. Humankind does not have all the answers to everything yet.
    B. The spirit or consciousness which animates a person or animal during life and which exits the body at death has mass which exhibits the properties of a vortex. This consciousness has sufficient mass to respond to centrifugal force as well as gravitational force. The center of this vortex also, like all spinning bodies, has some degree of gravitational pull. The vortex stops spinning at "death" ( transformation through the center of the vortex and out into another dimension that has not been "discovered" by science yet). At the time of transformation the centrifugal force ends, but the gravitational pull of the Earth continues to act on the remaining physical mass of the body. Thus making the body "heavier" since there is no longer a centrifugal force at work.
    The vortex which our galaxy is both pulls everything towards the black hole at its center--and at the same time flings everything away--as does our expanding universe.
    So that's my hypothesis--have fun tearing it apart! :-D Good night.
  7. Aug 16, 2011 #6


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    Tearing it apart? Simple. Even if it were true (which it isn't), spinning objects don't weigh less than stationary ones.
  8. Aug 17, 2011 #7
    brendahnelson, as you noted, the idea of an object being in two places at the same time IS quite preposterous. The difference between quantum physics theory and the teapot around Jupiter theory is that quantum physics has an extraordinary amount of observation and evidence to back it up, where as the teapot theory does not (and neither does the weight of life theory).

    Were it not for this extraordinary evidence, you would indeed be called a crackpot if you claimed that an object can be in two places, and rightfully so. Even Einstein was agaisnt quantum theory before it became irrefutable.

    This is why DaveC's point remains: YOU need to put forth a plausible hypothesis and extraordinary evidence to back up an extraordinary claim, and you can't just pull it out of your @$$ or have it rest on further extraordinary claims (as you have done).

    As for your question, I'm 100% certain that there have indeed been done tests to see if a body's weight changes before and after it is alive, both for that purpose in itself, or as a part of some other tests. Without checking the results, I'm also 100% certain that there is no significant difference.
  9. Aug 17, 2011 #8


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    Dave's argument is based on very real knowledge of how the world works. When he says he cannot conceive of a reason that a dead body would weigh more than a live body so soon after death it is NOT because he cannot think of a situation, it is because the requirements for that to happen would go against the laws of nature.

    To the best of my knowledge they have not. Quantum Mechanics and related principles does not allow one object to be in two different places at once. You can transfer states of a system, but not the system itself.


    Unfortunately the rest of your post is complete nonsense.

    I'm not going to go step on my cat and then put him on a scale, so the only thing I can say is that ALL of science says that it is not possible. And since science merely describes nature, then ALL of nature that we have observed and cataloged and so forth has shown us that it is not possible.
  10. Aug 17, 2011 #9

    Doc Al

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    Sorry, but PF is not the place for wild speculation. Please review our rules, which are linked at the top of every page. In particular, see our policy regarding 'overly speculative posts'.

    Thread closed.
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