B Gravity: Attractive or Repellent? Unanswered Questions

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Am I missing something? For if Gravity is an attractive force is there not a repellant force? Or is gravity the only force?
 
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Gravity isn't a force in general relativity. But there isn't a form of repulsive gravity, no.
 
Your question is very unclear. Please be more precise and give proper reference to where your ideas are taken from.

It is also very clear that your question is not A-level. An A tag indicates that you have an understanding of the subject equivalent to that of a graduate student in physics working with GR. I am changing the thread tag to B-level.
 
Ibix said:
there isn't a form of repulsive gravity

Careful. The effects of dark energy (or other things with a similar stress-energy tensor, such as a scalar field) can be viewed as "repulsive gravity"--for example, making the universe's expansion accelerate instead of decelerate. A better way of saying what I think you're trying to say here is that there are not two "gravities"; there is just spacetime curvature, which is related to stress-energy by the Einstein Field Equation. Different kinds of spacetime curvature can have different effects, not all of which look like ordinary "gravity"; but they all come from one fundamental equation, not two.
 
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In addition GR allows for negative pressure which would create 'repulsive gravity'.
 
MeJennifer said:
In addition GR allows for negative pressure which would create 'repulsive gravity'.

Negative pressure--more precisely, negative pressure with a magnitude greater than 1/3 of energy density--is what makes dark energy, a scalar field, etc. create "repulsive gravity" (make the universe's expansion accelerate).
 
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