Astronomy & Space Science · AST-458
Spacetime & the Equivalence Principle: Physical Mechanisms
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Mechanism
Mechanism of Spacetime & the Equivalence Principle
In a small freely falling elevator, objects float together because they share the same gravitational acceleration; locally gravity can be transformed away. Over larger regions, tidal effects remain because gravitational acceleration varies from place to place, revealing curvature that no single accelerating frame can eliminate.
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- 01Black Holes and Curved Spacetime — SummaryOpen source ↗
OpenStax Astronomy 2e
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Gravitational redshift, light deflection, orbital precession, clock-rate differences, and gravitational waves all follow from curved-spacetime physics.
supported · checked Sep 22, 2026In a small freely falling elevator, objects float together because they share the same gravitational acceleration; locally gravity can be transformed away.
supported · checked Sep 22, 2026The equivalence principle links acceleration and gravity by stating that sufficiently local experiments in a freely falling laboratory cannot distinguish free fall in a gravitational field from inertial motion without gravity.
supported · checked Sep 22, 2026