The relativistic relativistic energy–momentum relationship is:(adsbygoogle = window.adsbygoogle || []).push({});

[tex]E^2 = \left(pc\right)^2 + \left(m_0c^2\right)^2[/tex]

The relativistic energy (for a mass) is:

[tex]E = \gamma m_0c^2[/tex]

It has been said that the curvature of space is contributed to by photons, not just mass. However:

- The curvature of space produced by a photon field is virtually undetectable as photons are simply not packed dense enough.
- The ability for a photon to follow a curvs ed path is based primarily on the mass of the celestial objects. Doubling the energy of a photon only does not double this curvature and indeed no detectable diffraction has occurred as a result of curvature of space.

If it is still true that photons themselves produce some amount of curvature, then the invariant mass of system [itex]m_0[/itex] cannot account for this curvature. However, neither can the following:

- [itex]E^2 = \left(pc\right)^2 + \left(m_0c^2\right)^2[/itex] is relative to the observer because [itex]m_0[/itex] is fixed according to SR, not just [itex]c[/itex], while [itex]p[/itex] is relative to the observer, requiring [itex]E^2[/itex] to be relative to the observer.
- [itex]E = \gamma m_0c^2[/itex] is relative to the observer because [itex]\gamma[/itex] is defined relative to the observer, requiring [itex]E[/itex] to be relative to the observer.

B.T.W. In SR, [itex]m_0[/itex] is not a time-invariant mass, but a frame-invariant mass. Photons colliding head-on have been shown to produce additional [itex]m_0[/itex].

So I ask, "What energy term determines gravity in GR?" My basic premise of course is that this quantity should not be dependent on the observer.But, maybe velocity time dilationrelative to eachhas something to do with the apparent difference in curvature (more velocity time dilation would mean greater perceived acceleration of bodies in orbit around the mass). Does [itex]\sqrt{\left(pc\right)^2 + \left(m_0c^2\right)^2}[/itex] give us the amount of energy involved in this curvature?mass

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# What energy term determines gravity in GR?

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