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Is speed of thought greater than light?

  1. Jan 17, 2015 #1
    Earlier it was considered difficult to measure speed of light and many few have thought of actually calculating it.
    But it was Maxwell who proposed speed of light and gave the numerical value with some notable members according to sources.
    One may consider it as a philosophical question, but is any research done on it?
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  3. Jan 17, 2015 #2


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    I don't think the question is meaningful because thought seems to be a multitude of processes in parallel. If you want to measure the speed of the impulse from a single neuron firing, then it is more like the speed of electricity than the speed of light and it wouldn't represent "the speed of thought"
  4. Jan 17, 2015 #3
    Thought would be a consequence of neural activity in the brain, and things like the speed of conduction of electrical impulses through neurons or the speed of neurotransmitters across a synapse have been measured and found to be far slower than light.

    According to this study (this is a news article, not a peer-reviewed paper, so I might be misunderstanding the research), it takes the brain 13 milliseconds to identify an image. The Libet experiment (which has been criticised) shows the brain's conscious activity may occur up to half a second later than conscious processing. Milliseconds, fractions of a second... we're talking short amounts of time by human standards, but enormous amounts of time for a photon. In that 13 milliseconds it apparently takes you to process an image (and your eyes are, what, less than 20cm in front of the occipital lobe in your brain which processes visual information?), a photon could travel 3897 kilometres - a little more than the distance from London to Jerusalem. Compared to light, all our neural processes are very, very slow indeed!

    The only sense in which "thought" could be said to be "faster than light" is that we could imagine travelling faster than light, I suppose.
  5. Jan 17, 2015 #4


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    Complex thoughts such as these are so much denser than light that they can't travel very fast. Hard thoughts (as opposed to soft ones) have this property of higher density that slows them down when traveling in vacuum.
  6. Jan 17, 2015 #5


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    No one can answer your question until you tell us what you mean by "the speed of thought" or, indeed, what you mean by thoughts "travelling". If you mean the obvious- electrical activity in the brain- that's easily measured. It is far less than the speed of light.
  7. Jan 17, 2015 #6
    Of which compound is brain made of? Is it a organic one? How it is conducting electricity. What is the initial force that is put on the brain to develop electrical signals. How are we able to control our brain in the first place by just thoughts?

    How are the brain atoms moving, generating signals? Dreams are said to made of electric impulse while sleeping. But they are random or creative thoughts.
  8. Jan 17, 2015 #7
    Yeah I mean electrical activity.
  9. Jan 17, 2015 #8
    What exactly is thought?
  10. Jan 17, 2015 #9
    Electrical activitities taking place in our brains by some force. Can you tell the origin of this force which I am asking in above posts?
    What are hard or soft thoughts?
  11. Jan 17, 2015 #10
    I am here referring thoughts as electrical activity.The sending of signals. But by this one interesting question arises and I guess it might be a flaw for my entire thread.
    We are developing signals in our brain and analyzing it in brain itself.

    So there is no distance to travel and time lapse is also zero for our brains .

    Speed = distance/time. Distance= 0, time=0 here we get a indeterminate form which might be solved by l hopital rule.

    This is a question involving maths , chemistry, physics as well as some philosophy, I guess?
  12. Jan 17, 2015 #11


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    Nonsense. If there is no "time lapse" then there is no activity. You seem to be just throwing out undigested thoughts. It is, as I said, easy to measure the speed of electrical signals in the brain and they are far, far slower than the speed of light. If you have to ask "Of which compound is brain made of? Is it a organic one? How it is conducting electricity.", how can you possibly assert "there is no distance to travel and time lapse is also zero"?
  13. Jan 17, 2015 #12
    I think origin of thought may go deeper to the Darwin's evolution theory.We in the survival struggle kept developing our brain from primitive to having nervous system to now up to pre frontal cortex onwards and latest in human to neo cortex and all previous parts included.In addition to spatial we can go beyond animals to imagine time involving scenarios and hence our brain becomes an anticipation machine.Desire is what might be giving rise to thought for better survival.
    Forces behind these processes are obviously electromagnetic only because they can't be other three for reactions in brain.
    This topic actually links to biology as well.
    Speeds are already discussed in above posts.
  14. Jan 17, 2015 #13
    Sorry but where are the signals generated in brain going to for measuring their speed?
  15. Jan 17, 2015 #14


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    Neural impulse transmission rate is directly proportional to diameter, or radius, of the neuron/nerve fiber carrying the impulse. For the normal wiring in humans (arms, legs, motor activity) ~ 20 m/s.
    How many compounds would you like? People haven't begun to assay, let alone understand brain chemistry.
    Last edited by a moderator: Jan 17, 2015
  16. Jan 17, 2015 #15


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    Raghav, it seems as though you are just throwing out questions at random. It would be much better if you would read up on the brain and then ask more targeted questions.
  17. Jan 17, 2015 #16


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    They are going to other parts of the brain. As others have said, the speed of propagation of an action potential is very well studied. The velocity is about 2 m/s for unmyleinated axons and 20-60 m/s for myelinated axons. Far far less than the speed of light.
  18. Jan 17, 2015 #17
    Read up on action potentials, synapses and neurotransmitters. The answers to your questions aren't really physics or philosophy, they're more neuroscience and biology.
  19. Jan 17, 2015 #18


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    Signals are travelling between neurons in different parts of the brain. This is a non-zero distance over a on-zero time.

    I think what you might be grappling with is the distinction between brain (a physical mass of chemistry and electrical signals) and mind, an emergent property of the fabulously complex interactions within the brain.
  20. Jan 18, 2015 #19
    Yeah I will first study the brain topic and then ask if any doubts.
    Sorry I am deviating from the topic but can you all @phinds ,@DaleSpam ,@Bystander ,@DaveC426913 ,@Amaterasu21 ,@gianeshwar ,@HallsofIvy ,@Q_Goest open Google and search
    Is speed of thought greater than light.
    You will see the topic referenced by physics forum, but there is some description written
    16 hours ago - Fixed. ;) Job half done. Now you have to delete threads 17 and 20. And 21.
    From where it is coming? I can't see it here.
    Hope somebody would help.
  21. Jan 18, 2015 #20


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    It's not clear what 'many few' means here.

    It's true Maxwell used the speed of light in his electromagnetic theory, but he was hardly the first to have proposed that light had a finite speed, and the speed of light had been experimentally measured, with continuing refinements in its accuracy of measurement, for decades before Maxwell was born.


    At the time Maxwell was developing his theory, the speed of light had been measured by Foucault to be 298,000 ± 500 km/s, which is close to the modern value for c.
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