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Is it helpful in formulating theories to assume the opposite of what we see?

  1. Oct 2, 2007 #1
    Maybe this can lead to some absurd things that make no sense, but sometimes it may be enlightening.

    For instance, we think that gravity is an attractive force. Maybe we can ask "What if it's really repulsive instead"? What would it take to make gravity be repulsive and still see the results we see from experiment? Do the manipulations required to get it to work also seem to correspond with reality? This might not be a good example but in general can or has this method be used with other phenomena to better understand them or perhaps discover new things?

    Why not throw bizarre things like this against the wall and see if anything sticks?

    What if light is really not moving at all and everything else is?
    What if mass really decreases as you accelerate?
    What if objects don't spin but instead the universe spins around them?
    What if galaxies are not flying apart but instead are actually getting closer?
  2. jcsd
  3. Oct 2, 2007 #2
    What if light is really not moving at all and everything else is? Isnt everything in constant motion?

    What if mass really decreases as you accelerate? Why would speed of an object traveling through space affect its mass? It would however affect its time, supposedly the faster you travel through space the slower you age, if you could break the speed of light you would enter the 4th dimention(but at the same time you couldnt exist in this consciencness. I forgot were i read this interesting concept but it made sence to me.

    What if objects don't spin but instead the universe spins around them? How can the universe spin if there are no bounderies to it?

    As far as the "gravity actually is a force that repels opjects", how can it repel itself when it draws to atoms together to make up objects?

    Well just my input.
  4. Oct 2, 2007 #3
    Maybe objects in space dont spin, but also the universe doesnt. What if it's just you who spins.
  5. Oct 2, 2007 #4
    Only after a 12-pack, brother.
  6. Oct 2, 2007 #5
    O now reading the main question " Is it helpful in formulating theories to assume the opposite of what we see?" I would say yes, it helps put realistic idea's into more plain sight.
  7. Oct 4, 2007 #6
    Well as one example, objects which reflect light; We see frequencies that the object cannot absorb reflecting. We call the object that color, but really the object could be described based on the frequencies it can absorb. Things aren't always what they seem. We dont even see the object, we just see how it rflects light. Our sense are limited in that way and sometimes things aren't as they seem.
  8. Oct 4, 2007 #7
    Also if light is a wave and not a particle, then it is not really travelling very far, it is just vibrations. For example if you take a garden hose and suddenly give it a wip you can watch the wave move along the hose. The wave moves, and we can calculate how long it takes for the wave to reach the end of the hose, but it is the speed of the energy that we measure and not the speed of the hose itself.

    The only thing is that if light is a wave and not a particle, then it must propigate through something ie. it must have a "hose", and as far as anyone has been able to prove, it doesn't.
  9. Oct 4, 2007 #8


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    This discussion seems rather strange, and I have no idea why it's in the cosmology forum! Your idea seems to be "why don't we take all the observational evidence we can find, disregard it and build a theory that says the complete opposite?" It just doesn't make sense. Take, for example, your comment What if galaxies are not flying apart but instead are actually getting closer?"-- observational evidence for the last 70 years has agreed with the underlying theory that the universe is expanding, and thus galaxies are moving away from one another. So, why on earth would we try and build a theory that says the opposite? The fundamental point of having a theory or model of anything is that it agrees with observation!
  10. Oct 8, 2007 #9
    I'm not saying that we disregard it at all. All I'm saying is that it might be helpful in understanding the current theory to form an opposite theory. It might lend insights we didn't think of. Is there a way for an opposite theory to agree with observations? If so, what would it take? If you find there is no way to make it happen then you've reinforced your original theory and better understood the underpinnings of it. But what if you DO find something interesting and new? This is above all a method for developing new insights.
    Last edited: Oct 8, 2007
  11. Oct 8, 2007 #10


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    But by definition, an opposite theory would disagree with all observations; it would require the observations be opposite to what we actually do observe! I just don't understand your reasoning. It's one thing saying "we have a theory that predicts some of the observations; lets change some of the structure of it to predict other observations," but a completely different thing to say "we have a theory, lets make the opposite and see if it still works"-- of course it wouldn't!
  12. Oct 8, 2007 #11
    This discussion probably should be moved to the philosophy area :)
  13. Oct 8, 2007 #12
    Well, maybe I worded the question improperly. I just meant that you would try to formulate a potential solution which also agrees with experiment but which is very different from the generally accepted one. My point is that you might find something interesting if you challenged "accepted" ideas, even if that interesting thing just confirms what you already thought. What if mass actually lacks or shields gravity and vacuum exhibits repulsive gravity, so that mass becomes a "hole" for other mass to be "pushed" into rather than pulled? I'm not a scientist (obviously, right?) so you'd probably immediately see what's wrong with that example, but maybe you could come up with some better ones. Maybe even in it's obvious wrongness there is something to be gained from the thought experiment.
    Last edited: Oct 8, 2007
  14. Oct 11, 2007 #13
    This is an interesting idea because both models, although completely conceptually opposite, would both be matematically proveable. Also it would be very hard to test which theory 'is correct' as their detectable effects would be analogous.

    It is more a choice of what do you think is more appealing. You could conceptualize gravity as a pulling force, caused by all matter, or conceptualize it as a pushing force from surrounding space plasma, where the net force of attraction between masses occur as the shielding effect of matter.

    The difference is only the concept, all observed and measureable results would be entirely the same, and would describe the same law of gravity.
  15. Oct 12, 2007 #14


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    What is not seen is at least as important to science as is what is seen. Neither solution works well without the other. So the answer is a resounding YES. Sometimes our theories encompass a great deal of what is observed, but is contraindicated by a few observations. We tend to go with the majority, assuming the theory is mostly correct, but may need tweaked. It seems like a reasonable approach to me. No cosmological theory I am aware of is 'tweak' proof. The problem with ATM theories is the extreme lengths they require to accomodate the occasional freak observation. They invariably fail to accomodate more observations than they invalidate. Pointing out the failures is not the problem, promoting an even more flawed explanation is a problem.
    Last edited: Oct 12, 2007
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