# General theory of relativity&Planet orbits

## Main Question or Discussion Point

Hi all,
Only one is true at a time "general theory of relativity or Planetary orbits are elliptical...plz clarify me I will thank full to you..

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Assuming that I am correctly comprehending and/or inferring what you are asking,

The statements:
"[The] general theory of relativity [is generally accurate and applicable]"
AND
"Planetary orbits are elliptical."

are both generally true and accurate (in standard usage and understanding) and are in no way mutually exclusive or contradictory.

.... or perhaps I misunderstood what is being asked.

diogenesNY

• Klystron
the force of gravity in fact arises from the curvature of space and time. Einstein proposed that objects such as the sun and the Earth change this geometry.
planet orbits are depends on curvature of space And distance from that planet to sun
So planet orbits must be cerculer instead of elliptical.

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PeroK
Homework Helper
Gold Member
the force of gravity in fact arises from the curvature of space and time. Einstein proposed that objects such as the sun and the Earth change this geometry.
planet orbits are depends on curvature of space And distance from that planet to sun
So planet orbits must be cerculer instead of elliptical.
Both Newton and Einstein did extensive calculations to show that their theories led to elliptical orbits for the planets. In both cases you need to use the mathematical description of the theory to calculate this. Both theories generate essentially the same energy equation, although in GR there is an extra term, which is negligible for planetary orbits, but not in other cases.

You can't just guess the shape of planetary orbits without using mathematics.

Finally, planetary orbits depend on the geometry of spacetime, not just space.

• davenn
Further to the point, regardless of Newtonian or otherwise... the orbit of a planet is a matter of (fairly complex) kinematics, with factors such as collisions with other celestial bodies (meteors, comets, etc) having effects, as well as complex effects of other gravity wells (such as other planets) in the system. There are also complex variables associated with how any given planet formed (or was captured), adding yet more potential eccentricities.

A planet orbiting around a star is not defined by a simple, clean perfectly abstract 2 body equation.

There is a complex dance of both ongoing and intermittent forces at play. The solar system is a very busy place. Lots going on.

diogenesNY

Last edited:
• davenn
mathman
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