Testing Einstein in a Harvard Elevator Shaft
Between nineteen fifty-nine and nineteen sixty, two Harvard researchers measured gravitational time dilation across a twenty-two point five meter tower inside Jefferson Physical Laboratory. Using gamma rays and an ultra-precise resonance technique, their desktop-scale apparatus confirmed Albert Einstein's equivalence principle in a terrestrial environment.
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Harvard physicists measured gravitational frequency shifts across a seventy-four foot elevator shaft.
A British team raced Harvard to prove Einstein's gravity prediction in a laboratory setting.
A helium-filled tube prevented air molecules from scattering delicate iron-fifty-seven gamma rays.
A temperature difference of just one degree could completely erase the predicted gravitational signal.
Flipping the apparatus upside down cancelled out hardware flaws to isolate the gravitational effect.
The nineteen sixty results confirmed general relativity within ten percent using ground-based instruments.
- 01Intro1 min
- 02The Tower and the Transatlantic Race2 min
- 03Taming the Gamma Ray2 min
- 04The Thermal Trap and the Inversion Trick3 min
- 05Precision Physics Takes Over Gravity2 min
- 06Outro1 min
- Pound–Rebka experiment - Wikipedia
- 1.6: The Equivalence Principle (Part 2)
- aps.org
- youtube.com
- aldebaran.cz
- mindat.org
- aps.org
- gsjournal.net
- aps.org
- Pound-Rebka experiment Definition & Example | nuclear-power.com
- nasa.gov
- aps.org
- Pound–Rebka experiment Facts for Kids
- semanticscholar.org
- annualreviews.org
- aps.org
- aip.org
- Book spotlight: Testing Einstein
- What were the findings of the pound rebka experiment
- relativity.li
- home
- Why We Believe in General Relativity
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