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Thinking about gravity and ineria

  1. Mar 27, 2003 #1
    Thinking about gravity and ineria I had the following thought. Please, give me your thought about it and feel free to blow holes in it.
    When any object with mass moves, even in what we may perceive as a straight line with constant velocity on a curved surface or within a curved spacetime, whether closed or not , it must move in an orbital path. Obviously we may not recognize or be able to define the path but it would have to be orbital within a curved spacetime if no other force were acting upon it. In any accelerated motion we would be able to detect and define that accelerated motion and see it as curved or speeding up or slowing down.
    The object would be at a minimum kinetic energy state for the orbit that it occupies even if it was sitting on my kitchen table and appeared motionless to me. In order to move it in relation to us, the table or it's local spacetime energy would have to be applied to it to get it to change it's orbit. We would have to add energy for it to reach a "higher" orbit and thus slow it velocity or subtract energy from it for it to reach a "lower" orbit increasing its relative velocity. No matter how we attempt to move any object of mass we have to apply energy to change its orbit in curved spacetime. It's energy state, whether seen as kinetic or potential, would be changed. Actually in such a reference there is no real difference between kinetic and potential energy. Even sitting on a "higher shelf" in my kitchen increasing it's potential energy actually increases it's kinetic energy in its orbit in spacetime though not in reference to me or my kitchen.
    Last edited by a moderator: Feb 4, 2013
  2. jcsd
  3. Mar 28, 2003 #2
    Space-Time continuum is a curved surface. not curved space. there is no 'higher orbit' or 'lower orbit' on such a surface.
  4. Mar 28, 2003 #3
    I think that your wrong. As I understand relativity and everything that I've read about it. Spacetime itself is curved by the presence of mass. It is still being speculated whether there is enough mass in the universe for space time to be a closed or open curve. From what I'm reading now we are not sure space time itself is a continum or made up of quantums. It is also speculated that it is foamy which is how tunneling happens and the galexies are in clusters with great voids in between. I know nothing. This is just what I've been reading and what I think that I understand from what is written. Please do not take offense. I do appreciate your resonding. I am only dicussing specutations I barely understand if at all.
  5. Mar 28, 2003 #4


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    Re: Inertia

    Greetings Royce !

    Calm down dude/gal !
    It is perfectly alright(on PF) to ask about
    stuff you do not know or understand. That
    is the prime purpose of this forum.

    Now, your original message is not entirely
    clear. It is unclear what you want to ask
    and your description is somewhat "foggy".
    Please, clarify a bit what you want to say and
    aspecialy what you want to ask and I'm sure
    we'll all be happy(if able, of course) to help you.

    "The important thing is not to stop questioning.
    Curiosity has its own reason for existing."
    Albert Einstein

    Live long and prosper.
  6. Mar 28, 2003 #5
    Re: Inertia

    got myself burnt by a hot steam thro' the hole i made inadvertantly..!

    just joking.. no offence taken / intended..
  7. Mar 28, 2003 #6
    I don't really have a question. I was pondering gravity and inertia and the thought that all constant motion in curved spacetime must be orbital in nature i.e. in freefall. Inertia then becomes the energy or force required for the object to change orbit or energy state.
    It seemed to me that Newton's law that all objects tend to remain in their present state of motion and the the law(?)that all objects tend to go to their lowest state of energy, were both true yet contradictory unless their lowest energy state was their present state of motion and I could only see that being possible if their motion was in the form of a stable orbit.
    I wanted some one else's input or thoughts about my speculations. Is my thinking all wrong? Einstein said the inertia and gravity would appear the same to someone in a closed room in free space. Yet no one knows what gravity is nor what inertia is.
    Perhaps I would be better had I posted this piece under theory developement instead. I find it very difficult to express this nebulous idea cleary in writing as it is not yet really clear in my mind.
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