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Scientist

Rainer Sachs

1932–2024 · astrophysics, cosmology, general relativity
American astrophysicist of German origin, one of the authors of the Sachs–Wolfe effect, which explains large-scale temperature fluctuations in the cosmic microwave background by gravitational perturbations in the expanding Universe. He also contributed to the theory of gravitational lensing, deriving equations that describe the distortion of light in the Universe. His work has become key in modern cosmology.

Biography

Rainer K. Sachs was born on 13 June 1932 in Frankfurt am Main, Germany. He emigrated to the USA, where he earned his doctorate at Syracuse University. He worked at the University of California, Berkeley, and at other research institutions. Together with Arthur M. Wolfe in 1967, he predicted the effect linking the anisotropy of the cosmic microwave background to gravitational potentials. His research covered general relativity, cosmology, and mathematical physics. He passed away on 16 January 2024.

Key discoveries

💡 Sachs began his scientific career in theoretical biology before switching to cosmology, where he achieved outstanding results.
Concepts
cosmic microwave backgroundgravityspacetime curvatureexpansion of the universe
Laws
Sachs–Wolfe effect
Scientists
Robert HookeJacob BekensteinRalph AlpherKarl SchwarzschildJoseph WeberAdam RiessEmmy NoetherChristian Doppler

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