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Interferómetro atómico medición de la constante newtoniana de la gravedad
J B Fixler1, G T Foster, J M McGuirk
1Department of Physics, Stanford University, Stanford, CA 94305-4060, USA.
Science (New York, N.Y.)
|January 6, 2007
Resumen
Los investigadores midieron la constante newtoniana de la gravedad (G) utilizando interferometría atómica. Este método independiente arrojó G = 6.693 x 10^-11 m^3 kg^-1 s^-2, crucial para validar las mediciones gravitacionales existentes.
Área de la Ciencia:
- Física de los fundamentos de la física.
- Metrología de la metrología.
- Física gravitacional La física gravitacional es la física de las fuerzas gravitacionales.
Sus antecedentes:
- La constante newtoniana de la gravedad (G) es una constante fundamental en la física.
- La medición precisa de G es crucial para probar las teorías gravitacionales y comprender las interacciones basadas en la masa.
- Los métodos tradicionales para medir G son susceptibles a errores sistemáticos.
Objetivo del estudio:
- Para medir la constante newtoniana de la gravedad (G) utilizando una nueva técnica de interferometría atómica.
- Proporcionar una medición independiente de G para validar los valores existentes.
- Para abordar posibles errores sistemáticos en las mediciones convencionales de G.
Principales métodos:
- Utilizó un gradiómetro de gravedad basado en la interferometría atómica.
- Se midió la aceleración diferencial de los átomos de cesio (Cs) enfriados por láser.
- Se desplazó una masa de plomo (Pb) bien caracterizada para detectar cambios en el campo gravitatorio.
Principales resultados:
- Se informó de un valor medido de G = 6.693 x 10^-11 m^3 kg^-1 s^-2.
- Se obtuvo un error estándar de la media de +/-0.027 x 10^-11 m^3 kg^-1 s^-2.
- Se ha determinado un error sistemático de +/-0.021 x 10^-11 m^3 kg^-1 s^-2.
Conclusiones:
- El método de interferometría atómica proporciona una medición precisa e independiente de G.
- Este resultado contribuye al esfuerzo en curso para refinar el valor de la constante newtoniana de la gravedad.
- Las mediciones independientes son vitales para identificar y mitigar los errores sistemáticos en las determinaciones de constantes fundamentales.
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