Cosmology‎

419 quotes found

"The universe is globe-shaped, either because that is the most perfect shape of all, needing no joint, an integral whole; or because that is the most capacious of shapes, which is most fitting because it is to contain and preserve all...The first and highest of all is the sphere of the fixed stars, which contains itself and all things, and is therefore motionless. It is the location of the universe, to which the motion and position of all the remaining stars is referred. For though some consider that it also changes in some respect, we shall assign another cause for its appearing to do so in our deduction of the Earth's motion. There follows Saturn, the first of the wandering stars, which completes its circuit in thirty years. After it comes Jupiter which moves in a twelve-year long revolution. Next is Mars, which goes round biennially. An annual revolution holds the fourth place, in which as we have said is contained the Earth along with the lunar sphere which is like an epicycle. In fifth place Venus returns every nine months. Lastly, Mercury holds the sixth place, making a circuit in the space of eighty days. In the middle of all is the seat of the Sun. For who in this most beautiful of temples would put this lamp in any other or better place than the one from which it can illuminate everything at the same time? Aptly indeed is he named by some the lantern of the universe, by others the mind, by others the ruler. Trismegistus called him the visible God, Sophocles' Electra, the watcher over all things. Thus indeed the Sun as if seated on a royal throne governs his household of Stars as they circle around him. Earth also is by no means cheated of the Moon's attendance, but as Aristotle says in his book On Animals the Moon has the closest affinity with the Earth. Meanwhile the Earth conceives from the Sun, and is made pregnant with annual offspring. We find, then, in this arrangement the marvellous symmetry of the universe, and a sure linking together in harmony of the motion and size of the spheres, such as could be perceived in no other way. For here one may understand, by attentive observation, why Jupiter appears to have a larger progression and retrogression than Saturn, and smaller than Mars, and again why Venus has larger ones than Mercury; why such a doubling back appears more frequently in Saturn than in Jupiter, and still more rarely in Mars and Venus than in Mercury; and furthermore why Saturn, Jupiter and Mars are nearer to the Earth when in opposition than in the region of their occultation by the Sun and re-appearance. Indeed Mars in particular at the time when it is visible throughout the night seems to equal Jupiter in size, though marked out by its reddish colour; yet it is scarcely distinguishable among stars of the second magnitude, though recognized by those who track it with careful attention."

- Universe

0 likesCosmology‎Nature
"In the beginning God created the heaven and the earth.And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters.And God said, Let there be light: and there was light.And God saw the light, that it was good: and God divided the light from the darkness.And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day.And God said, Let there be a firmament in the midst of the waters, and let it divide the waters from the waters.And God made the firmament, and divided the waters which were under the firmament from the waters which were above the firmament: and it was so.And God called the firmament Heaven. And the evening and the morning were the second day.And God said, Let the waters under the heaven be gathered together unto one place, and let the dry land appear: and it was so.And God called the dry land Earth; and the gathering together of the waters called he Seas: and God saw that it was good.And God said, Let the earth bring forth grass, the herb yielding seed, and the fruit tree yielding fruit after his kind, whose seed is in itself, upon the earth: and it was so.And the earth brought forth grass, and herb yielding seed after his kind, and the tree yielding fruit, whose seed was in itself, after his kind: and God saw that it was good.And the evening and the morning were the third day.And God said, Let there be lights in the firmament of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and years:And let them be for lights in the firmament of the heaven to give light upon the earth: and it was so.And God made two great lights; the greater light to rule the day, and the lesser light to rule the night: he made the stars also.And God set them in the firmament of the heaven to give light upon the earth,And to rule over the day and over the night, and to divide the light from the darkness: and God saw that it was good.And the evening and the morning were the fourth day.And God said, Let the waters bring forth abundantly the moving creature that hath life, and fowl that may fly above the earth in the open firmament of heaven.And God created great whales, and every living creature that moveth, which the waters brought forth abundantly, after their kind, and every winged fowl after his kind: and God saw that it was good.And God blessed them, saying, Be fruitful, and multiply, and fill the waters in the seas, and let fowl multiply in the earth.And the evening and the morning were the fifth day.And God said, Let the earth bring forth the living creature after his kind, cattle, and creeping thing, and beast of the earth after his kind: and it was so.And God made the beast of the earth after his kind, and cattle after their kind, and every thing that creepeth upon the earth after his kind: and God saw that it was good.And God said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth.So God created man in his own image, in the image of God created he him; male and female created he them."

- Universe

0 likesCosmology‎Nature
"In vain would one expect an answer from natural science, which indeed loyally declares that it is faced with an insoluble enigma. It is very true that one would demand too much from natural science as such; but it I salso certain that more deeply penetrates the problem the human spirit poured into philosophical meditation." The problem of the radical origin of the universe, then, is a philosophical problem, not a scientific one. The discourse now proceeds with a passage that is of close interest to us. The Pope argues that a personal subject, a mind enriched today by scientific knowledge, would judge compatible with the present view of the cosmos the idea of a creation of the universe from nothing, by a Creator God. The subject of this recognition - it is worth emphasizing - is not science or the scientific method, but man enriched by scientific knowledge, together with his philosophical and existential reflection. Here are the words of Pius XII: "A mind enlightened and enriched by modern scientific knowledge, which serenely evaluates this problem, is led to break the circle of an entirely independent and autochthonous matter, either because it is uncreated, or because it is self-created, and to trace it back to a Creator Spirit. With the same clear and critical gaze with which it examines and judges facts, it glimpses and recognizes therein the work of creative omnipotence, whose virtue, stirred by the powerful “fiat” uttered billions of years ago by the Creator Spirit, unfolded in the universe, calling into existence with a generous gesture of love matter exuberant with energy. It really seems that today's science, suddenly going back millions of centuries, has succeeded in witnessing that primordial “Fiat lux,” when out of nothingness burst with matter a sea of light and radiation, as the particles of the chemical elements split off and came together in millions of galaxies."

- Big Bang

0 likesCosmology‎TimeChronologically ordered theme pages to be converted to alphabetical ordering
"I say looking at the next 100 years that there are two trends in the world today. The first trend is toward what we call a type one civilization, a planetary civilization... The danger is the transition between type zero and type one and that’s where we are today. We are a type zero civilization. We get our energy from dead plants, oil and coal. But if you get a calculator you can calculate when we will attain type one status. The answer is: in about 100 years we will become planetary. We’ll be able to harness all the energy output of the planet earth. We’ll play with the weather, earthquakes, volcanoes. Anything planetary we will play with. The danger period is now, because we still have the savagery. We still have all the passions. We have all the sectarian, fundamentalist ideas circulating around, but we also have nuclear weapons. ...capable of wiping out life on earth. So I see two trends in the world today. The first trend is toward a multicultural, scientific, tolerant society and everywhere I go I see aspects of that birth. For example, what is the Internet? Many people have written about the Internet. Billions and billions of words written about the Internet, but to me as a physicist the Internet is the beginning of a type one telephone system, a planetary telephone system. So we’re privileged to be alive to witness the birth of type one technology... And what is the European Union? The European Union is the beginning of a type one economy. And how come these European countries, which have slaughtered each other ever since the ice melted 10,000 years ago, how come they have banded together, put aside their differences to create the European Union? ...so we’re beginning to see the beginning of a type one economy as well..."

- Planetary civilization

0 likesCivilizationsCosmology‎
"Both ancient and medieval observers had noted that in many respects nature appeared to be governed by the principle of simplicity, and they had recorded the substance of their observations to this effect in the form of proverbial s which had become currently accepted bits of man's conception of the world. That falling bodies moved perpendicularly towards the earth, that light travelled in straight lines, that projectiles did not vary from the direction in which they were impelled, and countless other familiar facts of experience, had given rise to such common proverbs as: 'Natura semper agit per vias brevissimas'; 'natura nihil facit frustra'; 'natura neque redundat in superfluis neque deficit in necessariis' [Nature always acts by the shortest path; nature does nothing in vain; nature never overflows into the unnecessary, nor is she deficient in what is necessary]. This notion, that nature performs her duties in the most commodious fashion, without extra labour, would have tended to decrease somewhat the repulsion which most minds must have felt at Copernicus; the cumbrous epicycles had been decreased in number, various irregularities in the Ptolemaic scheme were eliminated... That such a tremendous shift in the point of reference could be legitimate was a suggestion quite beyond the grasp of people trained for centuries to think in terms of a homocentric philosophy and a geocentric physics. ...Copernicus could take the step because... he had definitely placed himself in... [the] dissenting Platonic movement. ...It was no accident that he became familiar with the remains of the early Pythagoreans, who almost alone among the ancients had ventured to suggest a non-geocentric astronomy."

- Geocentric model

0 likesAstronomyCosmology‎History of science
"Let us... examine the point on which Newton, apparently with sound reasons, rests his distinction of absolute and relative motion. If the earth is affected with an absolute rotation about its axis, centrifugal forces are set up in the earth: it assumes an oblate form, the acceleration of gravity is diminished at the equator, the plane of Foucault's pendulum rotates, and so on. All these phenomena disappear if the earth is at rest and the other heavenly bodies are affected with absolute motion round it, such that the same relative rotation is produced. This is, indeed, the case, if we start ab initio from the idea of absolute space. But if we take our stand on the basis of facts, we shall find we have knowledge only of relative spaces and motions. Relatively, not considering the unknown and neglected medium of space, the motions of the universe are the same whether we adopt the Ptolemaic or the Copernican mode of view. Both views are, indeed, equally correct; only the latter is more simple and more practical. The universe is not twice given, with an earth at rest and an earth in motion; but only once, with its relative motions, alone determinable. It is, accordingly, not permitted us to say how things would be if the earth did not rotate. We may interpret the one case that is given us, in different ways. If, however, we so interpret it that we come into conflict with experience, our interpretation is simply wrong. The principles of mechanics can, indeed, be so conceived, that even for relative rotations centrifugal forces arise."

- Geocentric model

0 likesAstronomyCosmology‎History of science
"This model of the expanding universe I shall call the substratum. It achieves in the private Euclidean space of each fundamental observer the objects for which Einstein developed his closed spherical space. Although it is finite in volume, in the measures of any chosen observer, it has all the properties of an infinite space in that its boundary is forever inaccessible and its contents comprise an infinity of members. It is also homogeneous in the sense that each member stands in the same relation to the rest. This description of the substratum holds good in the scale of time in which the galaxies or fundamental particles are receding from one another with uniform velocities. This choice of the scale of time, together with the theory of equivalent time-keepers... makes possible the application of the Lorentz formulae to the private Euclidean spaces of the various observers. It thus brings the theory of the expanding universe into line with other branches of physics, which use the Lorentz formulæ and adopt Euclidean private spaces. ...[T]here is no more need to require a curvature for space itself in the field of cosmology than in any other department of physics. The observer at the origin is fully entitled to select a private Euclidean space in which to describe phenomena, and when he concedes a similar right to every other equivalent observer and imposes the condition of the same world-view of each observer, he is inevitably led to the model of the substratum which we have discussed."

- Expansion of the universe

0 likesAstronomyCosmology‎History of physicsSpectroscopyTheoretical physics