Gravitational Physics

Gravitational Physics

They were deep in the arcane of gravitational physics – twisters, renormalization of ghost propagators, time-like Killing vectors, non-Abelian gauge invariance, geodesic refocusing, eleven-dimensional Kaluza-Klein treatments of supergravity, and, of course, superunification.

The walls of the tunnel were undulating, closing in on the dodecahedron, squeezing it forward. A nice rhythm was being established. Every time the dodec would slow almost to a halt, it was given another squeeze by the walls. In some places it was tough going, the walls working hard, waves of contraction and expansion rippling down the tunnel. Elsewhere, especially on the straightways, they would fairly skip along.

A great distance away, Elie made out a dim point of light, slowly growing in intensity. A blue-white radiance began flooding the inside of the dodecahedron. She could see it glint off the black erbium cylinders, now almost stationary. The swelling brilliance ahead was striking and they were rushing toward it, shooting up the tunnel, and then erupting into what seemed to be ordinary space.

Something about gravitational physics is bothering me: If you are limited by the speed of light, it is difficult to hold a galactic empire together. Image : © Megan Jorgensen (Elena)

Before them was a huge blue-white sun, disconcertingly close. Elie knew in an instant it was Vega.

As she peered through the lens more closely, she thought she could see faint erratic flashes of light from its very center. Hawking radiation? No, its wavelength would be much too long. Or light from the planet Earth still rushing down the tube?

Planets. Where were the planets? She scanned the ring plane with the long-focal length lens, searching for embedded planets – or at least for the home of the beings who had broadcast the Message. In each break in the rings she looked for a shepherding world whose gravitational influence had cleared the lanes of dust. But she could find nothing.

Great Designer vs Natural Selection?

Great Designer vs Natural Selection?

T. H. Huxley, the most effective nineteenth-century defender and popularizer of evolution, wrote that the publications of Darwin and Wallace were a flash of light, which to a man who has lost himself in a dark night, suddenly reveals a road which, whether it takes him straight home or not, certainly goes his way…

Carl Sagan’s reflection, when he first made himself master of the central idea of the Origin of Species, was “How extremely stupid not to have thought of that!” (we suppose that Columbus’ companions said much the same)… The facts of variability, of the struggle for existence, of adaptation to conditions, were notorious enough; but none of us had suspected that the road to the heart of the species problem lay through them, until Darwin and Wallace dispelled the darkness.

Many people were scandalized – some still are – at both ideas, evolution and natural selection. Our ancestors looked at the elegance of life on Earth, at how appropriate the structures of organisms are to their functions, and saw evidence for a Great Designer. The simplest one-celled organism is a far more complex machine than the finest pocket watch. And yet pocket watches do not spontaneously, self-assemble, or evolve, in slow stages, on their own, from, say, grandfather clocks.

Something about the physics is bothering me. Image: © Megan Jorgensen (Elena)

A watch implies a watch-maker. There seemed to be no way in which atoms and molecules could somehow spontaneously fall together to create organisms of such awesome complexity and subtle functioning as grace ever region of the Earth. That each living thing was specially designed, that one species did not become another, were notions perfectly consistent with what our ancestors with their limited historical records knew about life.

The idea that every organism was meticulously constructed by a Great Designer provided a significance and order to nature and an importance to human beings that we crave still. A designer is a natural, appealing and altogether human explanation of the biological world. But, as Darwin and Wallace showed, there is another way, equally appealing, equally human, and far more compelling: natural selection, which makes the music of life more beautiful as the aeons pass.

In fact, the fossil evidence could be consistent with the idea of a Great Designer; perhaps some species are destroyed when the Designer becomes dissatisfied with them, and new experiments are attempted on an improved design. But this notion is a little disconcerting. Each plant and animal is exquisitely made; should not a supremely competent Designer have been able to make the intended variety from the start? The fossil record implies trial an error, an inability to anticipate the future, features inconsistent with an efficient Great Designer (although not with a Designer of a more remote and indirect temperament).

Einstein-Rosen Bridges

Einstein-Rosen Bridges

General Relativity admits a class of solutions, called wormholes, similar to black holes, but with no evolutionary connection – they cannot be generated, as black holes can, by the gravitational collapse of a star. But the usual sort of wormhole, once made, expands and contracts before anything can cross through; it exerts disastrous tidal forces, and it also requires – at least as seen by an observer left behind – an infinite amount of time to get through.

The key problem is holding the wormhole open. Such a wormhole would pose none of the other problems of black holes. It would have much smaller tidal stresses, two-way access, quick transit times as measured by an exterior observer, and no devastating interior radiation field. A macroscopic field is a kind of tension that could be used to prevent a wormhole from contracting fully. If the wormholes can be Einstein-Rosen bridges, we can give some answer.

Einstein-Rosen Bridge. In fact, the universe seems to have been determined and ordered in accordance with number, by the forethought and the mind of the creator of all things; for the pattern was fixed, like a preliminary sketch, by the domination of number pre-existent in the mind of the world-creating God (Nicomachus of Gerasa), Arithmetic I, 6 (ca. a.d. 100). Illustration by Elena

Wormholes can distribute at convenient intervals around innumerable stars in this and others galaxies. They resembled black holes, but they had different properties and different origins. They are not exactly massless, because she had seen the leave gravitational wakes in the orbiting debris of any star system. And through them beings and ships of many kinds traversed and bound up the Galaxy.

Wormholes. In the revealing jargon of theoretical physics, the universe is their apple and someone has tunneled through, riddling the interior with passegeways that crisscross the core. For a bacillus who lived on the surface, it was a miracle. But a being standing outside the apple might be less impressed.

The Glory and a Dim Memory

The Glory and a Dim Memory

The glory of the Alexandrian Library is a dim memory. Its last remnants were destroyed soon after Hypatia’s death. It was as if the entire civilization had undergone some self-inflicted brain surgery, and most of its memories, discoveries, ideas and passions were extinguished irrevocably. The loss was incalculable. In some cases, we know only the tantalizing titles of the works that were destroyed. In most cases, we know neither the titles nor the authors. We do know that of the 123 plays of Sophocles in the Library, only seven survived. One of those seven is Oedipus Rex. Similar numbers apply to the works of Aeschylus and Euripides. It is a little as if the only surviving works of a man named William Shakespeare were Corolanus and A Winter’s Tale, but we had heard that he had written certain other plays, unknown to us but apparently prize in his time, works entitled Hamlet, Macbeth, Julius Caesar, King Lear, Romeo and Juliet.

On the physical contents of the glorious Library not a single scroll remains. In modern Alexandria few people have a keen appreciation, much less a detailed knowledge, of the Alexandrian Library or of the great Egyptian civilization that preceded if for thousands of years. More recent events, other cultural imperatives have taken precedence. The same is true all over the world. We have only the most tenuous contact with our past. And yet just a stone’s throw from the remains of the Serapaeum are reminders of many civilizations: enigmatic sphinxes from pharaonic Egypt; a great column erected to the Roman Emperor Diocletian by a provincial flunky for not altogether permitting the citizens of Alexandria to starve to death; a Christian Church; many minarets; and the hallmarks of modern industrial civilization – apartment houses, automobiles, streetcars, urban slums, a microwave relay tower. There are a million threads from the past interwined to make the ropes and cables of the modern world.

A Gothic Bird. Photo by Elena

Men of Honor

We have devoted attention to some of our ancestors whose names have not been lost: Eratosthenes, Democritus, Aristarchus, Hypatia, Leonardo, Kepler, Newton, Huygens, Champollion, Humason, Goddard, Einstein – all from Western culture because the emerging scientific civilization on our planet is mainly a Western civilization; but every culture – China, India, West Africa, Mesoamerica – has made its major contributions to our global society and had its seminal thinkers. Through technological advances in communication our planet is in the final stages of being bound up at a breakneck pace into a single global society. If we can accomplish the integration of the Earth without obliterating cultural differences or destroying ourselves, we will have accomplished a great thing.

In addition to Eratosthenes there was Dionysius of Thrace, the man who defined the parts of speech and did for the study of language what Euclid did for geometry; Herophilus, the physiologist who firmly established the brain rather than the heart is the seat of intelligence; Apollonius of Perga, the mathematician who demonstrated the forms of the conic sections (so called because the can be produced by slicing through a cone at various angles.

Eighteen centuries later, the writings of Apollonius on conic sections would be employed by Johannes Kepler in understanding for the first time the movement of the planets) – ellipse, parabola and hyperbola – the curves, as we now know, followed in their orbits by the planets, the comets and the stars; Archimedes, the greatest mechanical genius until Leonardo da Vinci; and the astronomer and geographer Ptolemy, who compiled much of what is today the pseudoscience of astrology: his Earth-centered universe held sway for 1,500 years, a reminder that intellectual capacity in no guarantee against being dead wrong.

And among those great men was a great woman, Hypatia, mathematician and astronomer, the last light of the library, whose martyrdom was bound up with the destruction of the library seven centuries after its founding…

The high peak of knowledge is perfect self-knowledge (Richard Of Saint-Victor, a prominent ancient thinker). Image: © Megan Jorgensen (ElenaB).

Human Science

Human Science

There is no other species on Earth that does science. It is, so far, entirely a human invention, evolved by natural selection in the cerebral cortex for one simple reason: it works. It is not perfect. It can be misused. It is only a tool. But it is by far the best tool we have, self-correcting, ongoing, applicable to everything. It has two rules. First: there are no sacred truths; all assumptions must be critically examined; arguments from authority are worthless.

Second: whatever is inconsistent with the facts must be discarded or revised. We must understand the Cosmos as it is and not confuse how it is with how we wish it to be. The obvious is sometimes false; the unexpected is sometimes true. Humans everywhere share the same goals when the context is large enough. And the Study of the Cosmos provides the largest possible context. Present global culture is a kind of arrogant newcomer. It arrives on the planetary stage following four and a half billion years of other acts, and after looking about for a few thousand years declares itself in possession of eternal truths. But in a world that is changing as fast as ours, this is a prescription for disaster. No nation, no religion, no economic system, no body of knowledge, is likely to have all the answers for our survival. There must be many social systems that would work far better than any now in existence. In the scientific tradition, our task is to find them.

A Proud Human Being. Photo by Elena

Only once before in our history was there the promise of a brilliant scientific civilization. Beneficiary of the Ionian Awakening, it had its citadel at the Library of Alexandria, where 2,000 years ago the best minds of antiquity established the foundations for the systematic study of mathematics, physics, biology, astronomy, literature, geography and medicine. We build on those foundations still. The Library was constructed and supported by the Ptolemys, the Grees kings who inherited the Egyptian portion of the empire of Alexander the Great. From the time of its creation in the third century B.C. until its destruction seven centuries later, it was the brain and heart of the ancient world.

Alexandria was the publishing capital of the planet. Of course, there were no printing presses then. Books were expensive; every one of them was copied by hand. The Library was the repository of the most accurate copies in the world. The art of critical editing was invented there. The Old Testament comes down to us mainly from the Greek translations made in the Alexandrian Library.