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Now it is generally true that the very greatest scientists in each discipline are unifiers. This is especially true in physics. Newton and Einstein were supreme as unifiers. The great triumphs of physics have been triumphs of unification. We almost take it for granted that the road of progress in physics will be a…
The discoveries of recent decades in particle physics have led us to place great emphasis on the concept of broken symmetry. The development of the universe from its earliest beginnings is regarded as a succession of symmetry-breakings. As it emerges from the moment of creation in the Big Bang, the universe is…
It happened three times in the past that theoretical astronomers invented a new planet on the basis of indirect and circumstantial evidence. The first time was in 1845 when Adams and Leverrier independently deduced the existence of the planet Neptune from the perturbations which it had produced in the motion of…
awking has written down an equation which looks rather like Planck's equation. Hawking's equation is S = kA, where S is the entropy of a black hole, A is the area of its surface, and k is a constant which I call Hawking's constant. Entropy means roughly the same thing as the heat capacity of an object. It is measured…
In the year 1900 Max Planck wrote down an equation, E = hv, where E is the energy of a light wave, v is its frequency, and h is a constant which we now call Planck's constant. Planck's equation was the beginning of quantum theory. It said that energy and {22} frequency are the same thing measured in different units…
He talked to us about the new theory of black holes which he had then just worked out. The idea of a black hole was one of the most dramatic consequences of Einstein's theory of gravity. According to Einstein's equations, a massive star at the end of its life, when it has exhausted its nuclear fuel, continues to…
It is time now to try to describe what a superstring really is. Here I run into the same difficulty which the geometer Euclid encountered 2,200 years ago. Euclid was trying to convey to his readers his idea of a geometrical point. For this purpose he gave his famous definition of a point: "A point is that which has no…
People who take pride in the same object can form a knightly order but not a brotherhood of loving sons. However, as soon as pride in the exploits of the fathers is replaced by grief over their death, we will begin to perceive the Earth as a graveyard and nature as a death-bearing force. Then politics will yield to…
This is our world now... the world of the electron and the switch, the beauty of the baud. We make use of a service already existing without paying for what could be dirt-cheap if it wasn't run by profiteering gluttons, and you call us criminals. We explore... and you call us criminals. We seek after knowledge... and…
TYPE I Characteristics: Planetary Society. Developed Technology. * understanding the laws of physics. * space technology. * nuclear technology. * electromagnetic communications. Initiation of spaceflight, interplanetary travel, settlement of space. Early attempts at interstellar communication. Starting to push…
"Take all the planets in a star system and dismantle them," she explains. "Turn them into dust – structured nanocomp, powered by heat exchangers, spread in concentric orbits around the central star. The inner orbitals run close to the melting point of iron, the outer ones are cold as liquid nitrogen, and each layer…
Matrioshka Brains (MB)1 are megascale computers constructed out of microelectronic and/or nanoscale components. MB may be constructed as shells around a star (internally powered Matrioshka Brains: IPMB) or may be constructed independently of a star if large amounts of power are harvested from stars in other locations…
Sometimes in an upper-level class I’ll assign a problem I don’t expect students to solve. It either involves some subtle trick, or requires theoretical techniques they haven’t yet learned. I assign them because I want students to struggle a bit with problems for which the solutions aren’t clear. “Wander into the…
Astronomy affords the most extensive example of the connection of physical sciences. In it are combined the sciences of number and quantity, or rest and motion. In it we perceive the operation of a force which is mixed up with everything that exists in the heavens or on earth; which pervades every atom, rules the…
"Most of you are too young to remember the term future shock. Back in the seventies, some people felt that technological progress was so rapid that people, normal people, couldn't cope with it; that they wouldn't have time to get used to the present before the future was upon them. A man named Toffler coined the term…
Our Sun is significantly enriched, having formed when the Universe was more than 9 billion years old in the plane of a spiral galaxy, one of the most enriched places in the Universe. Yet, when our Sun formed, it was still made out of — by mass — 71% hydrogen, 27% helium, and about 2% “other” stuff. If we convert that…
Milk production at a dairy farm was low, so the farmer wrote to the local university, asking for help from academia. A multidisciplinary team of professors was assembled, headed by a theoretical physicist, and two weeks of intensive on-site investigation took place. The scholars then returned to the university…
What you eventually discover as you continue to play is that Portal is a game about escaping from rooms that operate according to rules you are unaware of. You learn that each room is a puzzle, increasingly booby-trapped, and the game requires you to understand more and more complex physics in order to get out. If you…
Neutrinos, they are very small. They have no charge and have no mass And do not interact at all. The earth is just a silly ball To them, through which they simply pass. Like dustmaids down a drafty hall Or photons through a sheet of glass. They snub the most exquisite gas, Ignore the most substantial wall, Cold…
Faith is a fine invention For gentlemen who see; But microscopes are prudent In an emergency.