"In the beginning of 1917, two solutions of the field equations for a homogeneous isotropic universe had been found, which I... call the solutions "A" and "B." ...at that time only static solutions were looked for. It was thought that the universe must be a stable structure...In one of these solutions (B) the average density was zero, it was empty; the other one (A) had a finite density. ...In B, to get the real universe, we should have to put in a few galactic systems, in A we should have to condense the evenly distributed matter into galactic systems. The universe A... has an average density, but no expansion. It is therefore called the static universe. B, on the other hand... expands, and it could only parade in the garb of a static universe because there is nothing in it to show the expansion. B is therefore called the empty universe. Thus we had two approximations : the static universe with matter and without expansion, and the empty one without matter and with expansion.The actual universe... has both matter and expansion... In 1917... the actual value of the density was still entirely unknown, and the expansion had not yet been discovered."
Quote Details
Added by wikiquote-import-bot
Unverified quote
0 likes
CosmologistsAstronomers from the NetherlandsPhysicists from the NetherlandsMathematicians from the Netherlands
Original Language: English
Available Languages (1)
Sources
Imported from EN Wikiquote
https://en.wikiquote.org/wiki/Willem_de_Sitter
Revision History
No revisions have been submitted for this quote.
Categories
Willem de Sitter
Willem de Sitter (6 May 1872 – 20 November 1934) was a Dutch mathematician, physicist, astronomer and cosmologist who applied the general theory of relativity to the early investigation of the structure of the universe.
61 quotes on TrueQuotesView all quotes by Willem de Sitter →
Related Quotes
"There is no direct observational evidence for the curvature [of space], the only directly observed data being the mea…"
"It was early 1932, when Einstein and I both were at the California Institute of Technology in Pasedena, and we just d…"
"[Einstein's cosmological constant] is a name without any meaning. ...We have, in fact, not the slightest inkling of w…"
"Our own galaxy system is only one of a great many, and observations made from any of the others would show exactly th…"
"Gradually... during the second half of the nineteenth century, the uncomfortable feeling of dislike of the action at …"
"In electromagnetism... the law of the inverse square had been supreme, but, as a consequence of the work of Faraday a…"
"The inconsistency of first explaining matter by atoms and then explaining atoms by matter was only slowly realised, a…"
"How does it come about that we have been able to find satisfactory hypotheses to explain electricity and magnetism, l…"
"Gravitation is not only similar to inertia in its generality, it is also measured by the same number... the mass. The…"
"Gravitation is entirely independent of everything that influences other natural phenomena. It is not subject to absor…"