Eppur si Espande

• Autorzy: Abramowicz M. A. , Bajtlik S. , Lasota J.-P. , Moudens A.
• Języki publikacji: EN

Abstrakty

EN

The rather wide-spread belief that cosmological expansion of a flat 3D-space (with spatial curvature k=0) cannot be observationally distinguished from a kinematics of galaxies moving in a flat and non-expanding space is erroneous. We suggest that the error may have its source in a non relativistic intuition that imagines the Universe not as a space-time but separates space from time and pictures the cosmological expansion as space evolving in time. The physical reality, however, is fundamentally different - the expanding Universe is necessarily a curved space-time. We show here that the fact that the space-time is curved implies that the interpretation of the observed cosmological redshift as being due to the expansion of the cosmological 3D-space is observationally verifiable. Thus it is impossible to mimic the true cosmological redshift by a Doppler effect caused by motion of galaxies in a non-expanding 3D-space, flat or curved. We summarize our points in simple space-time diagrams that illustrate a gedanken experiment distinguishing between expansion of space and pure kinematics. We also provide all relevant mathematics. None of the previously published discussions of the issue, including a recent popular Scientific American article by Lineveaver and Davis, offered a similarly clear way out of the confusion.

Słowa kluczowe

EN

Cosmology: theory; Cosmology: miscellaneous

• Wydawca: Copernicus Foundation for Polish Astronomy
• Czasopismo: Acta Astronomica
• Rocznik: 2007
• Tom: Vol. 57, No. 2
• Strony: 139--148
• Opis fizyczny: Bibliogr. 3 poz., rys.

Twórcy

autor

Abramowicz M. A.

• Physics Department, Göteborg University, SE-412-96 Göteborg, Sweden
• Nicolaus Copernicus Astronomical Center, Bartycka 18, 00-716 Warszawa, Poland

autor

Bajtlik S.

• Nicolaus Copernicus Astronomical Center, Bartycka 18, 00-716 Warszawa, Poland

autor

Lasota J.-P.

• Institut d'Astrophysique de Paris, UMR 7095 CNRS, Université P. et M. Curie, 98bis Bd Arago, 75014 Paris, France
• Astronomical Observatory, Jagiellonian University, ul. Orla 171, 30-244 Kraków, Poland

autor

Moudens A.

• Master 2, Université de Paris-Sud 11, 91405 Orsay, France

Bibliografia

• Lineveaver, C.H., and Davis, T.M. 2005, Sci. Amer., 292, 36.
• Synge, J.L., and Schild, A. 1952, “Tensor Calculus”, University of Toronto Press, Toronto.
• Chodorowski, M. 2005, Pub. Astr. Soc. Australia, 22, 287.