“Another interesting feature of the Einstein universe is that in principle it could be circumnavigated by a ray of light.”

— Gerald James Whitrow

The Structure of the Universe: An Introduction to Cosmology (1949)
Context: Another interesting feature of the Einstein universe is that in principle it could be circumnavigated by a ray of light... it is unlikely that the rays would converge with sufficient accuracy. Nevertheless it is interesting to consider the possibility that some of the stars and nebulae which we see may after all be only optical ghosts.<!--p.79

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Gerald James Whitrow39

British mathematician 1912–2000

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“Another interesting feature of the Einstein universe is that in principle it could be circumnavigated by a ray of light… it is unlikely that the rays would converge with sufficient accuracy. Nevertheless it is interesting to consider the possibility that some of the stars and nebulae which we see may after all be only optical ghosts.”

Gerald James Whitrow (1912–2000) British mathematician

The Structure of the Universe: An Introduction to Cosmology (1949)

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“No dignity is higher in the eyes of God than royalty… Royalty is a light emanating from God, and a ray from the sun, the illuminator of the universe.”

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“The miracle of physics that I'm talking about here is something that was actually known since the time of Einstein's general relativity; that gravity is not always attractive. Gravity can act repulsively. Einstein introduced this in 1916… in the form of the cosmological constant, and the original motivation of modifying the equations of general relativity to allow this was because Einstein thought that the universe was static, and he realized that ordinary gravity would cause the universe to collapse if it was static. …The fact that general relativity can support this gravitational repulsion, still being consistent with all the principles that general relativity incorporates, is the important thing which Einstein himself did discover..”

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“This is our mission: to cast a ray of light and pass on.”

Maria Montessori (1870–1952) Italian pedagogue, philosopher and physician

Source: The Discovery of the Child (1948), Ch. 8 : The Exercises, p. 141
Variant translation:
This then is the first duty of an educator: to stir up life but leave it free to develop.
Context: This is our mission: to cast a ray of light and pass on. I compare the effects of these first lessons the impressions of a solitary wanderer who is walking serene and happy in a shady grove, meditating; that is leaving his inner thought free to wander. Suddenly a church bell pealing out nearby recalls to himself; then he feels more keenly that peaceful bliss which had already been born, though dormant, within him.
To stimulate life, leaving it free, however, to unfold itself, that is the first duty of the educator.
For such a delicate mission great art is required to suggest the right moment and to limit intervention, last one should disturb or lead astray rather than help the soul which is coming to life and which will live by virtue of it's own efforts.
This art must accompany the scientific method, because the simplicity of our lessons bears a great resemblance to experiments in experimental psychology.