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The eyes inhibit science

  1. Sep 10, 2006 #1
    I'm getting tired of reading about how some people think other physical dimensions would have to be seen with the eyes in order to exist.

    The way other dimensions are being conceptualized is inhibiting understanding of the subject. To use a popular phrase, those working in the field need to think outside Euclid’s box. We are conditioned to believe that not only are the Euclidean dimensions the only ones, but they are the only type of characteristics, with the possible exception of time, that can be physical dimensions. We are also conditioned to believe that physical dimensions only exist if we can see them with our eyes.

    The idea that the eyes see three dimensions is itself a result of conditioning. Each eye actually sends a flat 2-dimensional (width and height) image to the brain. The brain uses differences between the images received from the two eyes as well as visual clues like shadows to add a dimension indicating the length of the distance from the eyes to “see” in 3 dimensions. We’ve all seen babies try to reach out and touch things they are looking out. One reason for this is the developing brain is trying to learn how to judge distance. A baby’s brain may not know anything about inches or centimeters, but it can recognize if something is within an arm’s reach or not.

    Relying on the eyes to study physical reality has inhibited a scientific understanding before. Copernicus and Galileo had trouble because their theory didn’t conform to what the eyes seemed to be telling the brain. Opposition to Copernicus and Galileo might have been couched in religious terms, but the real problem was differences in perception. The intellectual leaders of the day rejected the new theories because their eyes told them the earth must be flat. They believed that if the earth were round they would be able to see the curvature of the earth with their eyes. People could not feel the earth revolving on its axis and the sun seemed to go around the earth just like the moon so the new theories seemed to contradict reality.

    People of that day couldn’t go into space to see the earth from space so determining that the earth was round and orbited the sun required ignoring the eyes and relying on math in the form of making calculations based on various observations over time.

    Recognizing that other dimensions exist will require relying on a strict mathematical examination of reality rather than just what the eyes seem to see. In the strict mathematical sense a dimension is a characteristic or variable. The only information the three Euclidean dimensions provide is length, width and height.

    If reality consisted only of these three dimensions, we would see a world in black and white only. Our eyes could only determine that something was in a location or not. They could not determine other characteristics of objects because characteristics like color require additional information provided by other variables. The eyes can determine if an object is reflecting or emitting light or if light is merely passing through it, but this characteristic of objects doesn’t depend on length, width or height. One object could not be a different temperature than another in a 3 dimensional reality, because temperature differences require an additional characteristic or variable.

    Our eyes cannot see gravity or a magnetic field. Yet, we know both exist because we can see or feel the effects of them. When we see something fall off the edge of a table we only see it fall. We do not see the invisible force that draws it to the floor.

    Gravity and magnetic attraction are not defined by simple length, width and height. The sun occupies a greater 3-dimensional area than earth and has higher gravitational attraction, but a black hole the size of a ping pong ball could have higher gravitational attraction than the sun. The density of matter might determine gravity, but density is a different dimension from length, width and height.

    Other dimensions would not necessarily have to be “higher” dimensions. There is no mathematical reason that would preclude the existence of various different “spaces” with different numbers of dimensions. For example, there could be an energy space and a matter space. One or more of the dimensions of these different spaces could be unique to that specific space. Other dimensions could be the same with the different spaces intersecting in the shared dimensions. We may perceive reality as 3-dimensional because the various spaces that make up reality intersect in the dimensions of length, width and height.

    If other dimensions are actually higher dimensions than the space in which we exist, then it would be impossible for the eyes to see them. They could only be perceived indirectly through the projection of their influence on our space. A projection from a higher dimensional space into a lower dimensional space can only possess the dimensions of the lower space.
  2. jcsd
  3. Sep 11, 2006 #2


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    I've never seen anyone claim that one had to see anything in order for it to exist. Where in the world did you see such a thing?
  4. Sep 11, 2006 #3
    Who says this? Armchair physicists armed with brian greene's book?

    Historical innaccuracy. By the time of the time of Columbus, most all educated people knew the earth was round. The greeks had settled the matter almost 2000 years before that.

    On the contrary, ever watch a large ship sail into the horizon? Pretty clear the earth isn't flat.

    You're confusing the notion of parameter space with spatial space.

    Except that in modern theories (QFT, GR) there are no such fields. Electromagnetic interactions are strictly particle to particle interactions, and gravity is a warping of space and time.

    Again, confusing parameter space with spatial space.

  5. Sep 11, 2006 #4
    Why can't we explain heat as particles in 3 different dimensions?
    Why can't we explain color in the same way?

    As far as I know heat is just rapid moving/vibrating atoms and molecules, all of which can be explained in 3 dimensions.

    The arisal of more dimensions is usually in string theory, not on the levels of atoms and molecules..
  6. Sep 11, 2006 #5
    You apparently are not following discussions of string theory. A common criticism of string theory is that the strings involving other dimension cannot be seen and thus cannot exist. The idea that the eyes need to be able to see other dimensions was recently mentioned in a Discover magazine interview of Professor Lisa Randall who has published a book on the subject.

    Some individuals in the field have tried to get around the criticism by suggesting that the strings are just "too thin" to be seen instead of treating such criticism as irrelevant. The point of my discussion is that our physical senses, including the eyes, may not be able to discover scientific truths by relying on simply seeing, feeling, etc. Many aspects of physical reality can only be discovered only indirectly with our physical senses.
  7. Sep 11, 2006 #6
    For heat to be three dimensional atoms must hold a constant position in 3-space. If they are moving a additional variable is needed to describe the change in location. When NASA gives the location of a space probe it provides a location with respect to some planet, for example, at a specific time and moving at a specific velocity. The velocity itself consists of two components, variables, a speed and a direction of travel. Thus 6 different pieces of information must be provided to locate such a probe.
  8. Sep 11, 2006 #7
    I think you're confusing cannot be seen, with cannot be observed. There is a significant difference. No actuall physicist is concerned with whether something can be visually seen, only whether it can be observed.

  9. Sep 11, 2006 #8

    Thats because you're getting the position in phase space. 3 space coordinates, 3 momentum coordinates. This is nothing novel, or surprising. Its still just 3 spatial dimensions though--not the same thing.
  10. Sep 11, 2006 #9


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    As a matter of fact, I have followed the discussion. While I haven't, in fact, taken a side, I do at any rate, understand the difference between "seeing" and "observing". Is it your position that a blind person is not capable of "observing" anything?
    Last edited by a moderator: Sep 12, 2006
  11. Sep 12, 2006 #10

    matt grime

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    I'm sorry, but I can't let the obvious contradiciton go by. You appear to be using the layman's appreciation of physics with the physicists knowledge of physics. Since the layman isn't the physicist they are entitled to whatever misunderstanding of science they wish to have. Physicists who actually do the work have none of the misapprehensions you seem to wish to ascribe to them.

    From what you've written one might think that you are the only person who knows anything about string theory and that the establishment is trying to suppress you because of its Euclidean thinking.
  12. Sep 12, 2006 #11
    See also the thread on "Measurement & Existence" at https://www.physicsforums.com/showthread.php?t=129299

    If you literally mean "seeing" in the sense of detecting with our eyes, then I do not agree that "what cannot be seen does not exist".

    But if by "seeing" you actually mean "detecting" (ie not necessarily with eyes & electromgantic radiation, but simply detecting by some means or another), then in a strictly scientific sense what cannot be detected does not exist.

    As far as we know, electromagnetic radiation "exists" in just 3 dimensions of space (in the sense that its properties are sensitive to only those 3 dimensions). Since we use electromagnetic radiation in order to "see" with our eyes, it follows that we are visually sensitive only to the 3 dimensions of space. There is absolutely no reason why we should necessarily be able to "see" other dimensions (even if they exist), any more than we can directly "see" dark matter (we cannot, because dark matter is hypothesised to not interact at all with EM radiation, except via the gravitational force - this latter allows us to indirectly see and detect dark matter).

    The notion that any N>4 dimensional hypothesis (such as string "theory") is unacceptable or incorrect simply because we cannot visually see the extra dimensions is therefore ridiculous. But the notion that an hypothesis is unscientific because we cannot in any way detect the entities which it assumes exist is quite correct.

    (I use scientific here in the Popperian sense that any scientific hypothesis needs to make testable predictions in order to be called scientific).

    Best Regards
    Last edited: Sep 12, 2006
  13. Sep 14, 2006 #12
    Following from the discussion on dimensional properties being observable, is anyone aware of any observed property of an N>4 dimension? I would be interested to know if it is even theoretically possible that their might be a physical effect present in the universe directly or indirectly caused by the existence of a dimension higher than that of space-time.

    I will attempt to further explain my question. The three dimensions of space being commonly labelled x,y,z can be ignored in this example as the fourth being time will be of most importance. Time is not labelled as a dimension of space as it causes a very different effect on our universe. The effect is change and it’s dimension is as we all know time. Using this view of the four dimensions we would say that spatial dimensions have the effect of position (a degree of movement) and a dimension being an axis x,y,z. So from here my question would be stated as follows. Do we know of any obvious effect (such as movement or change etc) on our universe that is due to dimensions other than those of space-time? I would prefer experimental evidence over mathematical models as I can think of numerous theories which explain phenomenon using extra dimensions but cannot find anything I would consider experimental evidence. My intension is to please my curiosity, I am not trying to say that higher dimension do or don’t exist outside our mathematical interpretations. After reading this thread my thoughts were lead to the question of the possible effect extra dimensions may have and I have not been able to satisfactorily answer the question myself. Therefore, all opinions would be appreciated.
  14. Sep 14, 2006 #13
    The fundamental problem is one of interpretation. The notion that I live in a 4D world (3 space and 1 time) is simply an interpretation that I place upon the perceptual information processed by (what I think is) my brain. But I might be a brain in a vat (or even worse, I might have no brain at all), and all of my perceptual information might be synthesised (how could I tell?). Thus my interpretation of sense-data in terms of existing within a 4D world may be false.

    The point I am trying to get at is that, when you get right down to it, there really is no fundamental philosophical difference between "experimental evidence" and "mathematical models" - because the notion of experimental evidence assumes (rather than proves) that our interpretation (ie mathematical model) of the world in terms of physical existence in 4 dimensions is correct.

    Best Regards
  15. Sep 15, 2006 #14
    MF, quick question regarding the brain in a vat concept..

    I think you are talking about two different things when you say that perceptual information may be synthesized, and that this somehow concludes that our perception of the world as a 4D entity may be wrong.

    If the world was synthesized, this wouldn't disprove that our world was 4D, it would rather tell us that our world is indeed 4D, but compared to another world (of which our world can be compared to or exists within as a synthesized entity) is not "real" as it were.

    However if the world was NOT 4D and it WAS synthesized, then the fact that it was synthesized does not tell us anything about its "4Dness."

    The last option is that when the world is not 4D but it is not synthesized either.
    Once again the two have no relation as I can see it.

    A synthesized world somehow implies another intelligence forcing this world upon us, while a non 4D world implies to me that our brain is somehow deceiving us (not with the help of another intelligence but rather it is just a limitation of our senses and intelligence.)

    Am I seeing this correctly to you or?

  16. Sep 15, 2006 #15
    If I am a metaphorical "brain in vat" in some other world it does not follow that this is a 4D brain in a 4D vat. Granted that in (what we believe to be) our world we cannot envisage how a brain in a vat could exist in anything other than a 4D world, but that is because we are limited to visualising in 4D. In the "real" world (wherein the vat exists) there may exist beings which perceive more or fewer dimensions than 4.

    Best Regards
  17. Sep 17, 2006 #16
    What change in the value of length, width or height explains whether an atom's temperature is 2 C or 3 C? The size of the atom's nucleus doesn't change with a change in temperture. The distance of the electrons from the nucleus can change, but the change involves the energy state of the electrons, not temperature.
  18. Sep 17, 2006 #17
    I doubt that the establishment is attempting to suppress me, because I doubt that I show up on its radar. The establishment in any field (not just in physical sciences) typically only concerns itself with specialists within the field who typically have been indoctrinated with what John Kenenth Galbraith referred to as "the conventional wisdom" a series of concepts that are accepted as fact which requiring no further examination even without definitive proof that the concept is valid.

    I'm concerned about the response that is given to the question of "why cant we see other dimensions." The public response by experts in the field tends to involve something like -- "well they are very tiny dimensions" -- instead of dealing with the issue of what a dimension is. The concept of more than 3 dimensions seems to be accepted in many areas except in the area of the dimensions of physical reality.

    We are taught theortical Euclidian geometry early in our lives and tend to assume that it describes the real world which it cannot unless the real world is made up of points which are the smallest elements of Euclidian geometry. If reality conformed to Euclidian theory then gravity could not warp space as suggested by Einstein because a warped space cannot exist within the context of Euclidian theory. If reality does not conform to Euclidian theory then reality may contain more dimensions that may involved other types of characteristics.

    I'm not comfortable with the term "string" theory. The term hampers the theory in part because it implies something that could be visible. "Lines of force" would seem a more accurate term because it implies something that might not have to be detected through its effect. The concept of other dimensions is an area I would have pursued had I not made a mistake 40 years ago in thinking that the reason politicians had trouble solving social problems was that they didn't know how to discover solutions rather than that they really weren't interested in finding solutions.
    Last edited: Sep 17, 2006
  19. Sep 18, 2006 #18
    You should rethink the last statement. Whether or not something exists is not dependent upon whether scientists can detect it with existing technology. Electrons, protons and neutrons existed long before J.J. Thompson discovered that atoms actually contained smaller particles. Quarks existed before they were detectable. Whether or not neutrinos exists doesn't depend on the ability of science to find a way to detect them as is also the case with dark matter and dark energy.

    Electromagnetic radiation may be perceived to exist in 3 dimensions, but how do the dimensions of length, width and height produce the specific characteristics of the radiation, including its luminosity, its ability to transfer heat from a source to a target, and its specific wavelengths all of which are independent characteristics.
    Our perception of color depends on reception of wave complexes rather than necessarily specific frequencies of light waves. Our perception of light as "white" depends upon receiving a range of light frequencies. My first experience with microcomputers was working with Professor Bob Nunley at the University of Kansas attempting to use micros to drive a LIGHT graphics generator. The system adjusted five variables to produce specific colors: the relative amounts of red, green and blue were adjustable as were variables to determine intensity/brightness and the lightness or darkness of the color.

    Your description of dark matter would be consistent with existence of a gravity space with gravity affected by matter in other spaces ( possibly the alternate / parallel universes of quantum physics) as well as matter in our space / universe.
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