Gravity is a pull.
And a path.

Newton measures the attraction. Einstein changes the shape of the stage. Hold the experiment still and see both descriptions respond.

Shared experiment

Change one body.
Watch both lenses.

Every result comes from your inputs. The canvas uses a visual scale, while the readouts preserve the physical quantities and units.

Experiment controls

SIMULATION RUNNING
Force9.82 kN
Acceleration9.820 m/s²
Orbit speed7.910 km/s
Orbit period84.35 min
Schwarzschild radius8.870 mm
Earth, through both lenses. Newton predicts a 9.820 m/s² acceleration at this distance. Einstein describes the same free-fall path as motion through curved spacetime. At Earth's surface, the Newtonian result is an excellent approximation.
One phenomenon

Two ways to read the motion.

Neither panel changes the experiment. It changes the question you ask of it.

Newton asks:
How strong is the pull?

Masses attract. More mass strengthens the force; more distance weakens it by the square.

F = Gm₁m₂ / r²

Einstein asks:
What path is straight here?

Mass-energy shapes spacetime. Free-falling matter follows the straightest available path through that geometry.

Gμν = 8πG Tμν / c⁴

Falling

A dropped object and an orbiting one are both in free fall. The orbit keeps missing the ground.

Weak fields

For planets, satellites, and everyday speeds, Newton's calculation is accurate and efficient.

Strong fields

Near black holes or at precision scales, curvature, clocks, and light paths matter.

Follow the path

Gravity does not switch theories.

Newton gives us the reliable shortcut. Einstein gives us the larger map. The shortcut emerges from the map when fields are weak and speeds are ordinary.

An orbit is a fall that keeps missing the ground.
A useful Newtonian picture

Keep the experiment, not just the answer.

Your report captures the exact setup, computed results, and the boundary between the two explanations.

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