Why the Universe Matters!

from Wikipedia:

The Ambassadors is a 1533 painting by Hans Holbein the Younger. Also known as *Jean de Dinteville and Georges de Selve,[1] after the two people it portrays, it was created in the Tudor period, in the same year Elizabeth I was born. Franny Moyle speculates that Elizabeth's mother, Anne Boleyn, then Queen of England, might have commissioned it as a gift for Jean de Dinteville, the French ambassador, portrayed on the left.[2] De Selve was a Catholic Bishop.

As well as being a double portrait, the painting contains a still life of meticulously rendered objects, the meaning of which is the cause of much debate. An array of expensive scientific objects, related to knowing the time and the cosmos are prominently displayed. Several refer to Rome, the seat of the Pope. A second shelf of objects shows a lute with a broken string, a symbol of discord, next to a hymnal composed by Martin Luther.

It incorporates one of the best-known examples of anamorphosis in painting. While most scholars have taken the view that the painting should be viewed side on to see the skull, others believe a glass tube was used to see the skull head on. Either way, death is both prominent and obscured until discovered. Less easily spotted is a carving of Jesus on a crucifix, half hidden behind a curtain at the top left.

The Ambassadors has been part of London's National Gallery collection since its purchase in 1890. It was extensively restored in 1997, leading to criticism, in particular that the skull's dimensions had been changed.

*Dinteville's motto was Memento mori, meaning "Remember thou shalt die."

...and if Time ran backwards in the anti-matter Universe?

from the Jowett summary of Plato's "Statesman"

No, not that; but another part of the story, which tells how the sun and stars once arose in the west and set in the east, and that the god reversed their motion, as a witness to the right of Atreus. 'There is such a story.' And no doubt you have heard of the empire of Cronos, and of the earthborn men? The origin of these and the like stories is to be found in the tale which I am about to narrate.

There was a time when God directed the revolutions of the world, but at the completion of a certain cycle he let go; and the world, by a necessity of its nature, turned back, and went round the other way. For divine things alone are unchangeable; but the earth and heavens, although endowed with many glories, have a body, and are therefore liable to perturbation. In the case of the world, the perturbation is very slight, and amounts only to a reversal of motion. For the lord of moving things is alone self-moved; neither can piety allow that he goes at one time in one direction and at another time in another; or that God has given the universe opposite motions; or that there are two gods, one turning it in one direction, another in another. But the truth is, that there are two cycles of the world, and in one of them it is governed by an immediate Providence, and receives life and immortality, and in the other is let go again, and has a reverse action during infinite ages. This new action is spontaneous, and is due to exquisite perfection of balance, to the vast size of the universe, and to the smallness of the pivot upon which it turns. All changes in the heaven affect the animal world, and this being the greatest of them, is most destructive to men and animals. At the beginning of the cycle before our own very few of them had survived; and on these a mighty change passed. For their life was reversed like the motion of the world, and first of all coming to a stand then quickly returned to youth and beauty. The white locks of the aged became black; the cheeks of the bearded man were restored to their youth and fineness; the young men grew softer and smaller, and, being reduced to the condition of children in mind as well as body, began to vanish away; and the bodies of those who had died by violence, in a few moments underwent a parallel change and disappeared. In that cycle of existence there was no such thing as the procreation of animals from one another, but they were born of the earth, and of this our ancestors, who came into being immediately after the end of the last cycle and at the beginning of this, have preserved the recollection. Such traditions are often now unduly discredited, and yet they may be proved by internal evidence. For observe how consistent the narrative is; as the old returned to youth, so the dead returned to life; the wheel of their existence having been reversed, they rose again from the earth: a few only were reserved by God for another destiny. Such was the origin of the earthborn men.

'And is this cycle, of which you are speaking, the reign of Cronos, or our present state of existence?' No, Socrates, that blessed and spontaneous life belongs not to this, but to the previous state, in which God was the governor of the whole world, and other gods subject to him ruled over parts of the world, as is still the case in certain places. They were shepherds of men and animals, each of them sufficing for those of whom he had the care. And there was no violence among them, or war, or devouring of one another. Their life was spontaneous, because in those days God ruled over man; and he was to man what man is now to the animals. Under his government there were no estates, or private possessions, or families; but the earth produced a sufficiency of all things, and men were born out of the earth, having no traditions of the past; and as the temperature of the seasons was mild, they took no thought for raiment, and had no beds, but lived and dwelt in the open air.

Such was the age of Cronos, and the age of Zeus is our own. Tell me, which is the happier of the two? Or rather, shall I tell you that the happiness of these children of Cronos must have depended on how they used their time? If having boundless leisure, and the power of discoursing not only with one another but with the animals, they had employed these advantages with a view to philosophy, gathering from every nature some addition to their store of knowledge;—or again, if they had merely eaten and drunk, and told stories to one another, and to the beasts;—in either case, I say, there would be no difficulty in answering the question. But as nobody knows which they did, the question must remain unanswered. And here is the point of my tale. In the fulness of time, when the earthborn men had all passed away, the ruler of the universe let go the helm, and became a spectator; and destiny and natural impulse swayed the world. At the same instant all the inferior deities gave up their hold; the whole universe rebounded, and there was a great earthquake, and utter ruin of all manner of animals. After a while the tumult ceased, and the universal creature settled down in his accustomed course, having authority over all other creatures, and following the instructions of his God and Father, at first more precisely, afterwards with less exactness. The reason of the falling off was the disengagement of a former chaos; 'a muddy vesture of decay' was a part of his original nature, out of which he was brought by his Creator, under whose immediate guidance, while he remained in that former cycle, the evil was minimized and the good increased to the utmost. And in the beginning of the new cycle all was well enough, but as time went on, discord entered in; at length the good was minimized and the evil everywhere diffused, and there was a danger of universal ruin. Then the Creator, seeing the world in great straits, and fearing that chaos and infinity would come again, in his tender care again placed himself at the helm and restored order, and made the world immortal and imperishable. Once more the cycle of life and generation was reversed; the infants grew into young men, and the young men became greyheaded; no longer did the animals spring out of the earth; as the whole world was now lord of its own progress, so the parts were to be self-created and self-nourished. At first the case of men was very helpless and pitiable; for they were alone among the wild beasts, and had to carry on the struggle for existence without arts or knowledge, and had no food, and did not know how to get any. That was the time when Prometheus brought them fire, Hephaestus and Athene taught them arts, and other gods gave them seeds and plants. Out of these human life was framed; for mankind were left to themselves, and ordered their own ways, living, like the universe, in one cycle after one manner, and in another cycle after another manner.

Enough of the myth, which may show us two errors of which we were guilty in our account of the king. The first and grand error was in choosing for our king a god, who belongs to the other cycle, instead of a man from our own; there was a lesser error also in our failure to define the nature of the royal functions. The myth gave us only the image of a divine shepherd, whereas the statesmen and kings of our own day very much resemble their subjects in education and breeding. On retracing our steps we find that we gave too narrow a designation to the art which was concerned with command-for-self over living creatures, when we called it the 'feeding' of animals in flocks. This would apply to all shepherds, with the exception of the Statesman; but if we say 'managing' or 'tending' animals, the term would include him as well. Having remodelled the name, we may subdivide as before, first separating the human from the divine shepherd or manager. Then we may subdivide the human art of governing into the government of willing and unwilling subjects—royalty and tyranny—which are the extreme opposites of one another, although we in our simplicity have hitherto confounded them.

Noether's Theorum

Noether's theorem states that every continuous symmetry of the action of a physical system with conservative forces has a corresponding conservation law. This is the first of two theorems (see Noether's second theorem) published by the mathematician Emmy Noether in 1918.[1] The action of a physical system is the integral over time of a Lagrangian function, from which the system's behavior can be determined by the principle of least action. This theorem applies to continuous and smooth symmetries of physical space. Noether's formulation is quite general and has been applied across classical mechanics, high energy physics, and recently statistical mechanics.[2]