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Does a human thought have mass?

  1. May 10, 2012 #1

    From what I understand, a thought is a series of electrical impulses. Does this mean that a thought has mass equivalent to the mass of an electron?

  2. jcsd
  3. May 10, 2012 #2
    No. A Human Thought is not an electron. The information in it is carried by the motion of electrons, but the electrons already existed. Conservation of Charge wouldn't allow a thought to be an electron, and neither would a few other principles.

    And also, what you're saying is that when someone thinks, their mass temporarily increases? Not really.
  4. May 10, 2012 #3


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    To simplify the case let me talk about a computer, and not about the human brain. The reason: a computer can be powered down, the human brain is always active.

    Relativistic physics describes that all forms of energy have a corresponding inertial mass. This relativistic effect is tiny, it's far smaller than our most sensitive instruments can measure, but we can talk about it as a exploration of the logical implications of our theories.

    If you have a loop of conducting wire then the state of current running in that loop is a higher state of energy than when no current is running. (Analogy in mechanics: a spinning object has rotational kinetic energy that a non-spinning object hasn't.)

    So if you have, say, a laptop computer then when it is in operation current is circulating, from the battery to the mainboard, most current flows through the processor, and back to the battery, and so on.

    That state of a current running in that loop, that energy, has a corresponding inertial mass.

    To process information we have created processors/computers, and when in operation there is a corresponding inertial mass. Of course, this inertial mass is far, far smaller than our most sensitive instruments can ever register. As I said, I'm just exploring the logical implications of our physics theories here.

    I assume that the human brain can be regarded as an information processing structure.
    So, pushing this reasoning to it's logical implications: the process of thinking has a corresponding energy state, which has a corresponding inertial mass

    To my knowledge the human brain is never inactive. During sleep the activity is different, but not less. An inactive brain is a dead brain. (That's why I shifted to discussing processors/computers. A computer can be switched off.)
    Last edited: May 10, 2012
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