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Thread: Calculating frame-dragging effects

  1. #1 Calculating frame-dragging effects 
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    I originally posted this in the physics section but no one seems able to provide any help in making this calculation:
    I was reading about PSR J0737-3039 - a binary pair of stars thought to be neutron stars - and I came across this table in Wikipedia:

    Property..........................Pulsar A.............................Pulsar B

    Spin period...................23 milliseconds..................2.8 seconds

    Mass..........................1.337 solar masses..........1.250 solar masses

    Orbital period 2.4 hours

    (ref. http://en.wikipedia.org/wiki/PSR_J07...double_pulsars )

    I was wondering what effect frame dragging would have on this system. Do they appear to a distant observer (us) to be orbiting each other faster than their masses would otherwise indicate if they weren't rotating at such high rates?

    I ask this because both components are massive, compact, have high spin rates (especially pulsar A) and are very close to each other (about 880,000 km).
    I'm hoping that a mathematical person might be able to explain the terms used in formulating the Kerr metric and how I can use it to calculate the frame dragging around (particularly) pulsar A.

    Chris


    It is difficult to say what is impossible, for the dream of yesterday is the hope of today and the reality of tomorrow.
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  3. #2  
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    Separately I calculated that the frame-dragging effect of pulsar A at an orbital distance of 880,000 km is 5.7x10^-13 rad/s.

    Can anyone verify this?

    Chris


    It is difficult to say what is impossible, for the dream of yesterday is the hope of today and the reality of tomorrow.
    Robert H. Goddard - 1904
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  4. #3  
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    http://www.physicsforums.com/

    Try the above forum. They are much better for physics questions.
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