![There is no direct observational evidence for the curvature [of space], the only directly observed data being the mean density and the expansion, which latter proves that the actual universe corresponds to the non-statical case. It is therefore clear that from the direct data of observation we can derive neither the sign nor that value of the curvature, and the question arises whether it is possible to represent the observed facts without introducing the curvature at all. Historically the term containing the 'cosmological constant λ' was introduced into the field equations in order to enable us to account theoretically for the existence of a finite mean density in a static universe. It now appears that in the dynamical case this end can be reached without the introduction of λ. (Willem de Sitter)](https://cdn.quotesdtb.com/img/quotes_images_webp/41/willem-de-sitter-account-849941.webp)
There is no direct observational evidence for the curvature [of space], the only directly observed data being the mean density and the expansion, which latter proves that the actual universe corresponds to the non-statical case. It is therefore clear that from the direct data of observation we can derive neither the sign nor that value of the curvature, and the question arises whether it is possible to represent the observed facts without introducing the curvature at all. Historically the term containing the 'cosmological constant λ' was introduced into the field equations in order to enable us to account theoretically for the existence of a finite mean density in a static universe. It now appears that in the dynamical case this end can be reached without the introduction of λ.
Willem de SitterRelated topics
account actual case clear constant containing curvature datum density direct end evidence existence expansion field introduction latter mean nor now observation order possible question sign space static term universe value factsRelated quotes
For what advantage is it, that the world enjoys profound peace, if thou art at war with thyself? This then is the peace we should keep. If we have it, nothing from without will be able to harm us. And to this end the public peace contributes no little: whence it is said, ‘That we may lead a quiet and peaceable life.' But if any one is disturbed when there is quiet, he is a miserable creature. Seest thou that He speaks of this peace which I call the third (inner, ed.) kind? Therefore when he has said, ‘that we may lead a quiet and peaceable life,' he does not stop there, but adds ‘in all godliness and honesty.' But we cannot live in godliness and honesty, unless that peace be established. For when curious reasonings disturb our faith, what peace is there? or when spirits of uncleanness, what peace is there?
John Chrysostom
With regard to domestic policy, the current burning issue is the racial question. Also in this field we will adopt the necessary solutions. Those who believe that we have obediently imitated anyone, or worse, acted on suggestions, are poor fools toward whom we do not know if we should direct our contempt or our pity. The racial problem did not suddenly burst out of nowhere, as those who are accustomed to brusque awakenings think - since they are used to long armchair naps. It is in relation to imperial conquest; because history teaches us that empires are conquered by arms but are held by prestige. And for prestige it is necessary to have a clear, severe racial consciousness, that establishes not only the differences, but also very clear superiorities.
Benito Mussolini
Why don't you believe in God? I get that question all the time. I always try to give a sensitive, reasoned answer. This is usually awkward, time consuming and pointless. People who believe in God don't need proof of his existence, and they certainly don't want evidence to the contrary. They are happy with their belief. They even say things like "it's true to me” and "it's faith.” I still give my logical answer because I feel that not being honest would be patronizing and impolite. It is ironic therefore that "I don't believe in God because there is absolutely no scientific evidence for his existence and from what I've heard the very definition is a logical impossibility in this known universe” comes across as both patronizing and impolite.
Ricky Gervais
In conclusion, it appears to me that nothing can be more improving to a young naturalist, than a journey in distant countries. It both sharpens, and partly likewise allays that want and craving, which, as Sir J. Herschel remarks, a man experiences although every corporeal sense is fully satisfied. The excitement from the novelty of objects, and the chance of success, stimulate him to increased activity. Moreover as a number of isolated facts soon become uninteresting, the habit of comparison leads to generalization. On the other hand, as the traveller stays but a short space of time in each place, his descriptions must generally consist of mere sketches, instead of detailed observation. Hence arises, as I have found to my cost, a constant tendency to fill up the wide gaps of knowledge, by inaccurate and superficial hypotheses.
Charles Darwin
As a theorist I have great advantages. All I need is a pencil (now a ball pen) and an empty pad of paper. There are analysts who sit and look vacantly out the window, but after the age of 20 I was not one of them. I ought to envy the new generation who have grown up with the computer, but I don't. None of them known to me sits idly at the console, improvising and experimenting in the way that a composer does at the piano. That ought to become increasingly possible. But up to now, in my observation, the computer is largely a black box into which researchers feed raw input and out of from which they draw various summarizing measures and simulations. Not having access to look around in the box, the investigator has less intuitive familiarity with the data than used to be the case in the bad old days.
Paul Samuelson
