A holograph of itself All [physical properties of matter] derive from the different patterns of the interaction of electrons and photons within the fields of the positively charged atomic nuclei, stabilized in a particular morphology by the interaction of the levels themselves. Matter is a holograph of itself in its own internal radiation. Matter versus Materials: A Historical View physics
Reality just seems to go on crunching I once met a fellow who thought that if you used General Relativity to compute a low-velocity problem, like an artillery shell, General Relativity would give you the wrong answer—not just a slow answer, but an experimentally wrong answer—because at low velocities, artillery shells are governed by Newtonian mechanics, not General Relativity. This is exactly how physics does not work. Reality just seems to go on crunching through General Relativity, even when it only makes a difference at the fourteenth decimal place, which a human would regard as a huge waste of computing power. Physics does it with brute force. No one has ever caught physics simplifying its calculations—or if someone did catch it, the Matrix Lords erased the memory afterward. Eliezer Yudkowsky, Rationality: From AI to Zombies physics
Corpuscles of nothing and atoms of something The structure of matter devolved ultimately into the intimate coexistence of something like corpuscles of nothing and atoms of something, segregating through the accidents of history to yield regions differing in density intimately interwoven on different scales. The experience of the world as well as human perception and analysis of any part of it is a matter of the angular scale of resolution and of the time necessary for making comparison between the different parts. Without such variations and without time to compare remembrances of them, nothing can be experiences. Cyril Stanley Smith, The Tiling Patterns of Sebastien Truchet and the Topology of Structural Hierarchy physicsperception
I know all about entropy Adell: I know as much as you do. Lupov: Then you know everything's got to run down someday. Isaac Asimov, The Last Question timedeathphysics
The Iridium System Several Low-Earth-Orbit (LEO) networks were proposed, but only one got off the ground: the Iridium system. The original Iridium proposal called for a "constellation" of 77 satellites, which gave the plan its name: the element iridium has atomic number 77, meaning that an iridium atom has 77 orbiting electrons. Before the satellites were launched, the constellation was scaled back to 66 active satellites, but no one wanted to change the name to Dysprosium. Brian Hayes, Infrastructure: A Guide to the Industrial Landscape physicscommunicationaerospacecosmos
Fermi Estimates and Dyson Designs An Article by Venkatesh Rao www.ribbonfarm.com A Fermi estimate is a quick-and-dirty solution to an arbitrary scientific or engineering analysis problem. Fermi estimation uses widely known numbers, readily observable phenomenology, basic physics equations, and a bunch of approximation techniques to arrive at rough answers that tend to be correct within an order of magnitude or so. The term is named for Enrico Fermi, who was famously good at this sort of thing. …It struck me that there is counterpart to this kind of thinking on the synthesis side, where you use similar techniques to arrive at a very rough design for a complex engineered artifact. I call such a design approach Dyson design, after the physicist Freeman Dyson, who was one of the best practitioners of it (not to be confused with inventor James Dyson, whose designs, ironically, are not Dyson designs). designphysics
The Image of the City A Book by Kevin Lynch mitpress.mit.edu To become completely lostApparencyOn the edge of something elseNothing there, after allPaths, edges, districts, nodes, landmarks+6 More 125 Best Architecture BooksScenes of thoroughgoing samenessClues for software design in how we sketch maps of cities urbanismplacecities
To become completely lost To become completely lost is perhaps a rather rare experience for most people in the modern city. We are supported by the presence of others and by special way-finding devices: maps, street numbers, route signs, bus placards. But let the mishap of disorientation once occur, and the sense of anxiety and even terror that accompanies it reveals to us how closely it is linked to our sense of balance and well-being. The very word "lost" in our language means much more than simple geographical uncertainty; it carries overtones of utter disaster. Disorientation citiesplacegeographywayfinding
Apparency Half a century ago, Stern discussed this attribute of an artistic object and called it apparency. While art is not limited to this single end, he felt that one of its two basic functions was "to create images which by clarity and harmony of form fulfill the need for vividly comprehensible appearance." In his mind, this was an essential first step toward the expression of inner meaning. artmeaningimagesharmonyform
On the edge of something else The most common response to the question of symbolism was nothing in the city at all, but rather the sight of the New York City skyline across the river. Much of the characteristic feeling for Jersey City seemed to be that it was a place on the edge of something else. placeidentity
Nothing there, after all When asked to describe or symbolize the city as a whole, the subjects used certain standard words: "spread out", "spacious", "formless", "without centers". Los Angeles seemed to be hard to envision or conceptualize as a whole. Said one subject: It's as if you were going somewhere for a long time, and when you got there you discovered there was nothing there, after all.
Paths, edges, districts, nodes, landmarks The contents of the city's images which are referable to physical forms can conveniently be classified into five types of elements: paths, edges, districts, nodes, and landmarks. Paths are the channels along which the observer customarily, occasionally, or potentially moved. Edges are the linear elements not used or considered as paths by the observer. They are the boundaries. Districts are the medium-to-large sections of the city, conceived of as having two-dimensional extent. Nodes are points, the strategic spots in a city into which an observer can enter, and which are the intensive foci to and from which they are traveling. Landmarks are another type of point-reference, but in this case the observer does not enter within them, they are external. They are usually a rather simply defined physical object: building, sign, store, or mountain. City districtsAs a kind of gateway cities
A directional quality Paths may not only be identifiable and continuous, but have directional quality as well: one direction along the line can easily be distinguished from the reverse. This can be done by a gradient, a regular change in some quality which is cumulative in one direction. changewayfinding
Introverts and extroverts Some regions are introvert, turned in upon themselves with little reference to the city outside them, such as Boston's North End or Chinatown. Others may be extrovert, turned outward and connected to surrounding elements. The common visibly touches neighboring regions, despite its inner path confusions. place
Junctions The junction, or place of a break in transportation, has compelling importance for the city observer. Because decisions must be made at junctions, people heighten their attention at such place and perceive elements with more than normal clarity. This tendency was confirmed so repeatedly that elements located at junctions may automatically be assumed to derive special prominence from their location. citieswayfindingchoice
What we are accustomed to call beautiful Most objects which we are accustomed to call beautiful, such as a painting or a tree, are single-purpose things, in which, through long development or the impress of one will, there is an intimate, visible linkage from fine detail to total structure. beautyobjectsstructure
A certain plasticity There are dangers in a highly specialized visible form; there is a need for a certain plasticity in the perceptual environment. If there is only one dominant path to a destination, a few sacred focal points, or an ironclad set of rigidly separated regions, then there is only one way to image the city without considerable strain. This one may suit neither the needs of all people, nor even the needs of one person as they vary from time to time. An unusual trip becomes awkward or dangerous; interpersonal relations may tend to compartmentalize themselves; the scene becomes monotonous or restrictive. citiesform
As plain as day The personal experience of most of us will testify to this persistence of an illusory image long after its inadequacy is conceptually realized. We stare into the jungle and see only the sunlight on the green leaves, but a warning noise tells us that an animal is hidden there. The observer then learns to interpret the scene by singling out "give-away" clues and by reweighting previous signals. The camouflaged animal may now be picked up by the reflection of its eyes. Finally by repeated experience the entire pattern of perception is changed, and the observer need no longer consciously search for give-aways, or add new data to an old framework. They have achieved an image which will operate successfully in the new situation, seeming natural and right. Quite suddenly the hidden animal appears among the leaves, "as plain as day." natureperceptionimages