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What is the problem with GR and quantum

  1. Dec 22, 2004 #1
    can anyone well versed in both GR and quantum explain to me the very underlying problems with these to theories, and if time was not a factor ie.... time was not as GR explains, would that solve any problems. To my knowledge time is the result of the geometry of the universe, as in theory, what if time is the fabric of the universe the sheet that all rests on, and mass lies on this sheet and allows space to exist and motion. Motion and the time sheet is the only thing that allows time intervals to be seen, no motion no time, sounds crazy but using a thought experiment totally shows the legitimacy, imagine a 3 dimensitional block no imagine two things lying in the same point in time, at A. now if two masses take off from that point one traveling faster one slower. the faster takes a more angled down approach in time, and as the limit of motion approaches that of C , theta of the angle down would reach 180 degrees meaning no times interval can be seen, whereas a slow objects would move near a straight line on the time sheet. all the effects or consequences of GR that i know of i can explain with this aspect, many of you may voice that this is same thing as norman but i don't think it is. its not anymore that we look at the change in motion with respect of tiime its the opposite we watch for the change in time with respect to motion. I think motion is the only way we can see what time is or shalli say a time interval. this isn't theory development or anything just want some clarifications so please don't warn me or anything. but taking time out of the equation would this help out with quantum problems.
  2. jcsd
  3. Dec 23, 2004 #2
    no idea? Sorry to bug yall?
  4. Dec 24, 2004 #3
    no more bothering yall but i will refine the question to just this, "what is the difficulty on squaring quantum with GR" thats it.
  5. Dec 25, 2004 #4


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    The problem is a mathematical one. When both theories have to be used together (e.g. inside a black hole), the solutions are mathematically nonsensical.
  6. Dec 25, 2004 #5
    Quantum mechanics describes things in flat space-time with a wave function that lives in Hilbert space. General relativity describes things in space-time with a stress-energy tensor that determines the curvature of space-time. Because of the dispersion ("uncertainty") relations, quantum particles do not have smooth or even continuous trajectories. General relativity assumes smooth trajectories. To get a theory of quantum gravity that approximates both general relativity and quantum mechanics, will take a subtle blend of the continuous and discontinuous.
  7. Dec 25, 2004 #6


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    Theory of Relativity gives times the same role that coordinates used to have for the last 350 years.That is to say,the introduction of space-time continuum made things fair.Time has had this role and apparently any of the existing theories and most probably none of the next will change it.

    I'm notmaking head or tail of what you're saying here.Time is merely a coordinate.Mass lies on the mass shell which is nothing but a 3D hypersurface in Minkowski space.The part with "allows space to exist" looks weird,and i mean "weird"... :rolleyes:
    Those are purely fantasmagorical thoughts/ideas.I suggest you temper your imagination and feed her with some math and physics.

  8. Dec 26, 2004 #7
    sorry daniel, the whole gives chance to exist part, moreless higgs boson stuff right.

    and rob, so the discontinuities in trajectories can't pan out with GR, correct???

    how would quantum gravity help, would the gravitron supposedly be able to make sense of these discontinuties.
  9. Dec 26, 2004 #8
    Yes and No
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