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Do We Know Nothing?

  1. Aug 9, 2008 #1
    I think the simplist answer is we know NOTHING about gravity.

    there is only theory on what gravity actually is... all we know are its effects.

    for example the mayans knew with amlost perfect accuracy about the suns behavior to such a degree that they could predict the earths presession. Buut they had absolutly no knowledge of anything ABOUT the sun, like nuclear fusion and photons.

    That is pretty much where we are at the moment. We understand gravity's behavior with an extraordinary degree of accuracy, however we know absolutly nothing about gravity.
     
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  3. Aug 9, 2008 #2

    russ_watters

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    Re: What do we know about gravity?

    Those two statements contradict each other. Being able to make accurate predictions is all that we ask of science.
     
  4. Aug 9, 2008 #3
    Re: What do we know about gravity?

    If that is all you want to know then I am envious.
     
  5. Aug 9, 2008 #4

    ZapperZ

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    Re: What do we know about gravity?

    This is misleading. If you look carefully at everything that you think you know, you will see that all you know is actually just your ability to describe something. The knowledge of a set of properties and behavior of something is what constitutes your ability to say that you know what it is. Now it doesn't mean that you know EVERYTHING about it, but it certainly does not allow you to say you know NOTHING about it.

    Physics is just that - our ability to describe the behavior of a system. There's no greater evidence to show that we know quite a bit about something when we can make quantitative prediction of what that something is going to do. Look at your modern electronics. I will even say that we know more about gravity than you know more about the behavior of your closest relatives.

    Zz.
     
  6. Aug 9, 2008 #5

    Defennder

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    Re: What do we know about gravity?

    The problem is, you can always keep asking "Why?" for any explanation offered. Unless you believe that the fundamental facts of our universe are somehow reducible to axioms of logic.
     
  7. Aug 9, 2008 #6
    Re: What do we know about gravity?

    lol... that wouldn't suprise me. I don't claim to be able to predict the behavior of my closest relatives.... AT ALL

    I don't want to start an argument. I am just trying to put across that saying all you want to know is the behavior of a "thing" is like saying all you want to know is how to drive a car but not caring how a car operates.

    Of course "why" will be the eternal question to every answer and I hope we will never stop asking.
     
  8. Aug 9, 2008 #7

    ZapperZ

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    Re: What do we know about gravity?

    Then don't claim that we know nothing about it. The pedestrian definition of "knowing nothing" simply does not apply here. Would you depend your life on something that we know nothing about? Honestly?

    You haven't shown an example where it fits into your criteria of knowing "something". If that doesn't exist, then your categorization that we know nothing about gravity is moot.

    Zz.
     
  9. Aug 9, 2008 #8
    Re: What do we know about gravity?

    To know something we would know the cause of gravity. We would also have a model that would work universally from macro to plank space. Perhaps a theory exists that I don't know of, but even then it will just be a theory.
     
  10. Aug 9, 2008 #9

    ZapperZ

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    Re: What do we know about gravity?

    But see, when you find the "cause" of something, that "explanation" really is a description at that lower level.

    You haven't managed to find an example in physics where you can say that there is this "cause". What about E&M? Or the strong force, etc... etc.? By your criteria, do you also claim that we know nothing about physics, and thus, we know nothing about everything in our universe?

    Zz.
     
  11. Aug 9, 2008 #10
    Re: What do we know about gravity?

    Your not far off :biggrin:

    I'm bound to get shot for saying this on a physics forum but to quote socrates "True knowledge exists in knowing that you know nothing."

    See what you made me do! This is a thread about gravity and you have reduced me to a level where philosophy has had to enter discussion!

    I warned you I didn't want to start an argument. :blushing:
     
  12. Aug 9, 2008 #11

    ZapperZ

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    Re: What do we know about gravity?

    Then you have a strange of not wanting to start an "argument" by knowingly starting something that you KNOW will get a reaction. And since when do you go by your understanding our your world based on some "quotation"?

    So you still haven't been able to show me an example of something that you know. Then I will resort to having ask you this: What is an apple?

    Or are you also claiming that you know nothing about an apple?

    Zz.
     
  13. Aug 9, 2008 #12
    Re: What do we know about gravity?

    ok... I am going to have to stop this now.

    Yes I can tell you what an apple is. and, like gravity, I can tell you how it behaves. If you want to know then pm me because you are taking this thread way off topic.
     
  14. Aug 9, 2008 #13

    ZapperZ

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    Re: Do We Know Anything?

    This is no longer off-topic. So tell me, what is an apple that you think you know?

    Zz.
     
  15. Aug 9, 2008 #14
    The thread title is contradictory. I'll give you a hint, it's within the part that says "know nothing."
     
  16. Aug 9, 2008 #15

    ZapperZ

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    It's a title that I came up on the fly since these posts were split from another thread. It is consistent with the first post.

    Zz.
     
  17. Aug 9, 2008 #16
    If I can assume what Seph83 may be saying, is that, he would like to know a little more of what's going on in the way gravity works---more of the 'reasons' how/why gravity works.

    Two hundred years ago to now, more knowledge has been gained as to the make up and the nature of things, but still there is no explanation written in any books as to the fundamental and foundational aspects of gravity. We know more about an apple in a lot of ways for 'what' an apple is, as to the same thinking as what is common knowledge/written about gravity (and a few more of those type of things).
     
  18. Aug 9, 2008 #17
  19. Aug 10, 2008 #18
    There was a PF member that said this...forgot the name, but to put it simply: science tells the how rather than the why.
     
  20. Aug 10, 2008 #19
    yep---there's a cop-out way physicists/scientists answer a lot of these 'questions' especially if someone asks something like, "why does gravity work the way it does?"

    The aloof answer physicists/scientists give is: " 'Why...?' is a question for philosophers not for scientists-----scientists blah, blah, blah....."--especially if its something they don't know the 'real' answer to.
     
    Last edited: Aug 10, 2008
  21. Aug 10, 2008 #20
    The problem with asking "What is gravity?" is that this is a loaded question; it assumes that 'gravity' is the name of something. General Relativity shows us that this is a bad assumption. This is the same problem that comes from a question like 'What is time?', this assumes that 'time' is the name of something. A better question would be "Under what circumstances do we use the word 'time'?", since this explores the meaning of the concept without starting with a loaded question.
     
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