Relativity versus Newtonian gravity

In summary, the conversation discusses the role of relativity in explaining gravity and the impact of relative velocity on the total energy of an object. It is mentioned that according to general relativity, the source of gravity is the stress-energy-tensor, which takes into account velocity. This differs from the Newtonian idea of mass and special "relativistic mass." The question of why an object's velocity does not affect its gravitational attraction to Earth is also raised.
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James Nelson
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I asked recently on another thread about relativity and its affect on gravitation. I have been informed that gravity is due to how energy bends spacetime, not the Newtonian idea of mass or even the special "relativistic mass."

However this leaves me wondering why general relativity does not involve velocity in its equations. According to E=(mc^2)/sqrt(1-v^2/c^2), relative velocity does have an impact on the total energy of an object. If so, why is it that an object traveling relative to Earth doesn't produce a larger gravitational attraction to Earth than an object of equal rest mass that is stationary?
 
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James Nelson said:
However this leaves me wondering why general relativity does not involve velocity in its equations.

It does. In GR the source of gravity is the stress-energy-tensor which depends on velocity.
 
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James Nelson said:
I have been informed that gravity is due to how energy bends spacetime, not the Newtonian idea of mass or even the special "relativistic mass."
It is the stress energy tensor which includes the density of energy, momentum, and stress.
 
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Related to Relativity versus Newtonian gravity

What is the difference between relativity and Newtonian gravity?

Relativity is a more comprehensive theory of gravity developed by Albert Einstein, while Newtonian gravity is a simpler approximation that is still accurate for most everyday applications. Relativity takes into account the curvature of space-time and the effects of high speeds and large masses, while Newtonian gravity assumes a flat space and only considers the influence of mass on objects.

Which theory is more accurate, relativity or Newtonian gravity?

Relativity is considered to be more accurate because it takes into account more factors and has been tested and confirmed by numerous experiments. However, for everyday situations with low masses and speeds, Newtonian gravity is still a reliable approximation.

Why do we still use Newtonian gravity if relativity is more accurate?

Newtonian gravity is simpler and easier to use for most everyday applications. It is also more intuitive and easier to understand than the complex concepts of relativity. Additionally, the differences between the predictions of Newtonian gravity and relativity are typically very small and only become significant in extreme situations.

Can relativity and Newtonian gravity be reconciled?

Many attempts have been made to reconcile relativity and Newtonian gravity, but so far no definitive theory has been accepted. Some scientists believe that a unified theory of gravity, which combines the principles of both relativity and Newtonian gravity, may be possible in the future.

How has the understanding of gravity evolved from Newton's time to today?

Newton's theory of gravity was groundbreaking and accurate for its time, but as technology and understanding of the universe advanced, it became clear that there were limitations and inaccuracies in his theory. Relativity was developed to better explain the complexities of gravity, and it has since been confirmed by numerous experiments and observations. The study of gravity continues to evolve as scientists strive to better understand this fundamental force.

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