Electron Beam Quotes

Centuries of navel-gazing. Millennia of masturbation. Plato to Descartes to Dawkins to Rhanda. Souls and zombie agents and qualia. Kolmogorov complexity. Consciousness as Divine Spark. Consciousness as electromagnetic field. Consciousness as functional cluster. I explored it all. Wegner thought it was an executive summary. Penrose heard it in the singing of caged electrons. Nirretranders said it was a fraud; Kazim called it leakage from a parallel universe. Metzinger wouldn't even admit it existed. The AIs claimed to have worked it out, then announced they couldn't explain it to us. Gödel was right after all: no system can fully understand itself. Not even the synthesists had been able to rotate it down. The load-bearing beams just couldn't take the strain. All of them, I began to realize, had missed the point. All those theories, all those drugdreams and experiments and models trying to prove what consciousness was: none to explain what it was good for. None needed: obviously, consciousness makes us what we are. It lets us see the beauty and the ugliness. It elevates us into the exalted realm of the spiritual. Oh, a few outsiders—Dawkins, Keogh, the occasional writer of hackwork fiction who barely achieved obscurity—wondered briefly at the why of it: why not soft computers, and no more? Why should nonsentient systems be inherently inferior? But they never really raised their voices above the crowd. The value of what we are was too trivially self-evident to ever call into serious question. Yet the questions persisted, in the minds of the laureates, in the angst of every horny fifteen-year-old on the planet. Am I nothing but sparking chemistry? Am I a magnet in the ether? I am more than my eyes, my ears, my tongue; I am the little thing behind those things, the thing looking out from inside. But who looks out from its eyes? What does it reduce to? Who am I? Who am I? Who am I? What a stupid fucking question. I could have answered it in a second, if Sarasti hadn't forced me to understand it first.

Every set of phenomena, whether cultural totality or sequence of events, has to be fragmented, disjointed, so that it can be sent down the circuits; every kind of language has to be resolved into a binary formulation so that it can circulate not, any longer, in our memories, but in the luminous, electronic memory of the computers. No human language can withstand the speed of light. No event can withstand being beamed across the whole planet. No meaning can withstand acceleration. No history can withstand the centrifugation of facts or their being short-circuited in real time (to pursue the same train of thought: no sexuality can withstand being liberated, no culture can withstand being hyped, no truth can withstand being verified, etc.).

It is also possible to carve atomic devices using electron beams. For example, scientists at Cornell University have made the world’s smallest guitar, one that is twenty times smaller than a human hair, carved out of crystalline silicon. It has six strings, each one hundred atoms thick, and the strings can be plucked using an atomic force microscope. (This guitar will actually play music, but the frequencies it produces are well above the range of the human ear.)

electron-beam lithography,

Each day, the moon’s gravitational field tugs at the earth as it rotates underneath. At CERN, this tiny stress caused the total length of the LEP tunnel to stretch and contract by about a millimeter (one-twenty-fifth of an inch) every day. Not such a big deal in a seventeen-mile-long beam pipe, but enough to cause a tiny fluctuation in the energy of the electrons and positrons—one that was easily detectable by the high-precision instruments. After some initial puzzlement at the daily energy variations, the CERN physicists quickly figured out what was going on.

The next big particle accelerator currently in the planning stage is the International Linear Collider (ILC), consisting of a straight tube approximately thirty miles long in which beams of electrons and anti-electrons will collide.

There was a school here now, in Concourse C. Like educated children everywhere, the children in the airport school memorized abstractions: the airplanes outside once flew through the air. You could use an airplane to travel to the other side of the world, but—the schoolteacher was a man who’d had frequent-flyer status on two airlines—when you were on an airplane you had to turn off your electronic devices before takeoff and landing, devices such as the tiny flat machines that played music and the larger machines that opened up like books and had screens that hadn’t always been dark, the insides brimming with circuitry, and these machines were the portals into a worldwide network. Satellites beamed information down to Earth. Goods traveled in ships and airplanes across the world. There was no place on earth that was too far away to get to. They were told about the Internet, how it was everywhere and connected everything, how it was us. They were shown maps and globes, the lines of the borders that the Internet had transcended. This is the yellow mass of land in the shape of a mitten; this pin here on the wall is Severn City. That was Chicago. That was Detroit. The children understood dots on maps—here—but even the teenagers were confused by the lines. There had been countries, and borders. It was hard to explain.

Silence. Then, “What does. This. Sound like?” “What does what sound like?” “Io is a sulfur-rich, iron-cored moon in a circular orbit around Jupiter. What does this. Sound like? Tidal forces from Jupiter and Ganymede pull and squeeze Io sufficiently to melt Tartarus, its sub-surface sulfur ocean. Tartarus vents its excess energy with sulfur and sulfur dioxide volcanoes. What does. This sound like? Io’s metallic core generates a magnetic field that punches a hole in Jupiter’s magnetosphere, and also creates a high-energy ion flux tube connecting its own poles with the north and south poles of Jupiter. What. Does this sound like? Io sweeps up and absorbs all the electrons in the million-volt range. Its volcanoes pump out sulfur dioxide; its magnetic field breaks down a percentage of that into sulfur and oxygen ions; and these ions are pumped into the hole punched in the magnetosphere, creating a rotating field commonly called the Io torus. What does this sound like? Torus. Flux tube. Magnetosphere. Volcanoes. Sulfur ions. Molten ocean. Tidal heating. Circular orbit. What does this sound like?” Against her will, Martha had found herself first listening, then intrigued, and finally involved. It was like a riddle or a word-puzzle. There was a right answer to the question. Burton or Hols would have gotten it immediately. Martha had to think it through. There was the faint hum of the radio’s carrier beam. A patient, waiting noise. At last, she cautiously said, “It sounds like a machine.

Hey, Hiro," the black-and-white guy says, "you want to try some Snow Crash?" A lot of people hang around in front of The Black Sun saying weird things. You ignore them. But this gets Hiro's attention. Oddity the first: The guy knows Hiro's name. But people have ways of getting that information. It's probably nothing. The second: This sounds like an offer from a drug pusher. Which would be normal in front of a Reality bar. But this is the Metaverse. And you can't sell drugs in the Metaverse, because you can't get high by looking at something. The third: The name of the drug. Hiro's never heard of a drug called Snow Crash before. That's not unusual -- a thousand new drugs get invented each year, and each of them sells under half a dozen brand names. But a "snow crash" is computer lingo. It means a system crash -- a bug -- at such a fundamental level that it frags the part of the computer that controls the electron beam in the monitor, making it spray wildly across the screen, turning the perfect gridwork of pixels into a gyrating blizzard. Hiro has seen it happen a million times. But it's a very peculiar name for a drug. The thing that really gets Hiro's attention is his confidence. He has an utterly calm, stolid presence. It's like talking to an asteroid. Which would be okay if he were doing something that made the tiniest little bit of sense. Hiro's trying to read some clues in the guy's face, but the closer he looks, the more his shifty black-and-white avatar seems to break up into jittering, hardedged pixels. It's like putting his nose against the glass of a busted TV. It makes his teeth hurt. "Excuse me," Hiro says. "What did you say?

Single photons are not usually evident, but in the laboratory we can produce a beam of light so faint that it consists of a stream of single photons, which we can detect as individuals just as we can detect individual electrons or buckyballs. And we can repeat Young’s experiment employing a beam sufficiently sparse that the photons reach the barrier one at a time, with a few seconds between each arrival. If we do that, and then add up all the individual impacts recorded by the screen on the far side of the barrier, we find that together they build up the same interference pattern that would be built up if we performed the Davisson-Germer experiment but fired the electrons (or buckyballs) at the screen one at a time. To physicists, that was a startling revelation: If individual particles interfere with themselves, then the wave nature of light is the property not just of a beam or of a large collection of photons but of the individual particles.

There are only two types of waves that can travel across the universe bringing us information about things far away: electromagnetic waves (which include light, X-rays, gamma rays, microwaves, radio waves…); and gravitational waves. Electromagnetic waves consist of oscillating electric and magnetic forces that travel at light speed. When they impinge on charged particles, such as the electrons in a radio or TV antenna, they shake the particles back and forth, depositing in the particles the information the waves carry. That information can then be amplified and fed into a loudspeaker or on to a TV screen for humans to comprehend. Gravitational waves, according to Einstein, consist of an oscillatory space warp: an oscillating stretch and squeeze of space. In 1972 Rainer (Rai) Weiss at the Massachusetts Institute of Technology had invented a gravitational-wave detector, in which mirrors hanging inside the corner and ends of an L-shaped vacuum pipe are pushed apart along one leg of the L by the stretch of space, and pushed together along the other leg by the squeeze of space. Rai proposed using laser beams to measure the oscillating pattern of this stretch and squeeze. The laser light could extract a gravitational wave’s information, and the signal could then be amplified and fed into a computer for human comprehension. The study of the universe with electromagnetic telescopes (electromagnetic astronomy) was initiated by Galileo, when he built a small optical telescope, pointed it at Jupiter and discovered Jupiter’s four largest moons. During the 400 years since then, electromagnetic astronomy has completely revolutionised our understanding of the universe.

We think of color as an attribute, but really it’s a happening: a constantly occurring dance between light and matter. When a beam of light strikes an object—let’s say a multicolor glass vase—it is effectively pelting the surface with tiny energetic particles known as photons. The energy of some of those photons is absorbed, heating the glass imperceptibly. But other photons are repelled, sent ricocheting back out into the atmosphere. It’s these photons, landing on our retinas, that create the sensation of color. The specific hue we see has to do with the energy of the photons: the high-energy short wavelengths look blue to us, while the low-energy long ones appear red. The brightest pigments, those found in flower petals and leaves as well as many commercial pigments, tend to have a more “excitable” molecular structure. Their electrons can be disturbed with very little light, making the colors appear intense to our eyes.

The top surface of the computer is smooth except for a fisheye lens, a polished glass dome with a purplish optical coating. Whenever Hiro is using the machine, this lens emerges and clicks into place, its base flush with the surface of the computer. The neighborhood loglo is curved and foreshortened on its surface. Hiro finds it erotic. This is partly because he hasn't been properly laid in several weeks. But there's more to it. Hiro's father, who was stationed in Japan for many years, was obsessed with cameras. He kept bringing them back from his stints in the Far East, encased in many protective layers, so that when he took them out to show Hiro, it was like watching an exquisite striptease as they emerged from all that black leather and nylon, zippers and straps. And once the lens was finally exposed, pure geometric equation made real, so powerful and vulnerable at once, Hiro could only think it was like nuzzling through skirts and lingerie and outer labia and inner labia. . . . It made him feel naked and weak and brave. The lens can see half of the universe -- the half that is above the computer, which includes most of Hiro. In this way, it can generally keep track of where Hiro is and what direction he's looking in. Down inside the computer are three lasers -- a red one, a green one, and a blue one. They are powerful enough to make a bright light but not powerful enough to burn through the back of your eyeball and broil your brain, fry your frontals, lase your lobes. As everyone learned in elementary school, these three colors of light can be combined, with different intensities, to produce any color that Hiro's eye is capable of seeing. In this way, a narrow beam of any color can be shot out of the innards of the computer, up through that fisheye lens, in any direction. Through the use of electronic mirrors inside the computer, this beam is made to sweep back and forth across the lenses of Hiro's goggles, in much the same way as the electron beam in a television paints the inner surface of the eponymous Tube. The resulting image hangs in space in front of Hiro's view of Reality. By drawing a slightly different image in front of each eye, the image can be made three-dimensional. By changing the image seventy-two times a second, it can be made to move. By drawing the moving three-dimensional image at a resolution of 2K pixels on a side, it can be as sharp as the eye can perceive, and by pumping stereo digital sound through the little earphones, the moving 3-D pictures can have a perfectly realistic soundtrack. So Hiro's not actually here at all. He's in a computer-generated universe that his computer is drawing onto his goggles and pumping into his earphones. In the lingo, this imaginary place is known as the Metaverse. Hiro spends a lot of time in the Metaverse. It beats the shit out of the U-Stor-It.

Marvin stood there. ‘Out of my way little robot,’ growled the tank. ‘I’m afraid,’ said Marvin, ‘that I’ve been left here to stop you.’ The probe extended again for a quick recheck. It withdrew again. ‘You? Stop me?’ roared the tank, ‘Go on!’ ‘No, really I have,’ said Marvin simply. ‘What are you armed with?’ roared the tank in disbelief. ‘Guess,’ said Marvin. The tank’s engines rumbled, its gears ground. Molecule-sized electronic relays deep in its micro-brain flipped backwards and forwards in consternation. ‘Guess?’ said the tank. ‘Yes, go on,’ said Marvin to the huge battle machine, ‘you’ll never guess.’ ‘Errrmmm …’ said the machine, vibrating with unaccustomed thought, ‘laser beams?’ Marvin shook his head solemnly. ‘No,’ muttered the machine in its deep gutteral rumble, ‘Too obvious. Anti-matter ray?’ it hazarded. ‘Far too obvious,’ admonished Marvin. ‘Yes,’ grumbled the machine, somewhat abashed, ‘Er … how about an electron ram?’ This was new to Marvin. ‘What’s that?’ he said. ‘One of these,’ said the machine with enthusiasm. From its turret emerged a sharp prong which spat a single lethal blaze of light. Behind Marvin a wall roared and collapsed as a heap of dust. The dust billowed briefly, then settled. ‘No,’ said Marvin, ‘not one of those.’ ‘Good though, isn’t it?’ ‘Very good,’ agreed Marvin. ‘I know,’ said the Frogstar battle machine, after another moment’s consideration, ‘you must have one of those new Xanthic Re-Structron Destabilized Zenon Emitters!’ 'Nice, aren’t they?’ agreed Marvin. ‘That’s what you’ve got?’ said the machine in condiderable awe. ‘No,’ said Marvin. ‘Oh,’ said the machine, disappointed, ‘then it must be …’ ‘You’re thinking along the wrong lines,’ said Marvin, ‘You’re failing to take into account something fairly basic in the relationship between men and robots.’ ‘Er, I know,’ said the battle machine, 'is it … ’ it tailed off into thought again. ‘Just think,’ urged Marvin, ‘they left me, an ordinary, menial robot, to stop you, a gigantic heavy-duty battle machine, whilst they ran off to save themselves. What do you think they would leave me with?’ ‘Oooh er,’ muttered the machine in alarm, ‘something pretty damn devastating I should expect.’ ‘Expect!’ said Marvin. ‘Oh yes, expect. I’ll tell you what they gave me to protect myself with shall I?’ ‘Yes, alright,’ said the battle machine, bracing itself. ‘Nothing,’ said Marvin. There was a dangerous pause. 'Nothing?’ roared the battle machine. ‘Nothing at all,’ intoned Marvin dismally, ‘not an electronic sausage.’ The machine heaved about with fury. ‘Well doesn’t that just take the biscuit!’ it roared, ‘Nothing, eh?’ Just don’t think, do they?’ ‘And me,’ said Marvin in a soft low voice, ‘with this terrible pain in all the diodes down my left side.’ ‘Makes you spit, doesn’t it?’ ‘Yes,’ agreed Marvin with feeling. ‘Hell that makes me angry,’ bellowed the machine, ‘think I’ll smash that wall down!’ The electron ram stabbed out another searing blaze of light and took out the wall next to the machine. ‘How do you think I feel?’ said Marvin bitterly. ‘Just ran off and left you did they?’ the Machine thundered. ‘Yes,’ said Marvin. ‘I think I’ll shoot down their bloody ceiling as well!’ raged the tank. It took out the ceiling of the bridge. ‘That’s very impressive,’ murmured Marvin. ‘You ain’t seen nothing yet,’ promised the machine, ‘I can take out this floor too, no trouble!’ It took out the floor too. ‘Hells bells!’ the machine roared as it plummeted fifteen storeys and smashed itself to bits on the ground below. ‘What a depressingly stupid machine,’ said Marvin and trudged away.

There are several sorts of scans, but the one of interest here is the CT (Computed Tomography) or “cat” scan. The CT with the lowest exposure is called EBT (Electron Beam Tomography). The exposure is very moderate and will not likely be a problem. All these machine work by rapidly spinning an x-ray around you. The EBT accomplishes this by moving the x-ray beam electronically, which is inherently much faster than moving it mechanically, as is done in a normal “cat” scan.

Following the experiments of Davisson and Germer and Thomson, scientists showed that all subatomic particles behave like waves: beams of protons and neutrons will diffract off samples of atoms in exactly the same way that electrons do. In fact, neutron diffraction is now a standard tool for determining the structure of materials at the atomic level: scientists can deduce how atoms are arranged by looking at the interference patterns that result when a beam of neutrons bounces off their sample. Knowing the structure of materials at the atomic level allows materials scientists to design stronger and lighter materials for use in cars, planes, and space probes. Neutron diffraction can also be used to determine the structure of biological materials like proteins and enzymes, providing critical information for scientists searching for new drugs and medical treatments.

So, if all material objects are made up of particles with wave properties, why don’t we see dogs diffracting around trees? If a beam of electrons can diffract off two rows of atoms, why can’t a dog run around both sides of a tree to trap a bunny on the far side? The answer is the wavelength: as with the sound and light waves discussed earlier, the dramatically different behavior of dogs and electrons encountering obstacles is explained by the difference in their wavelengths. The wavelength is determined by the momentum, and a dog has a lot more momentum than an electron.

For quantum physics, in addition to predicting and explaining phenomena that range over fifteen orders of magnitude in energy, has done something else: it has triggered a radical upheaval in our understanding of the world. In place of the tidy cause-and-effect universe of classical physics, quantum physics describes a world of uncertainties, or indeterminism: of limits to our knowledge. It describes a world that often seems to have parted company with common sense, a world at odds with some of our strongest intuitive notions about how things work. In the quantum world, subatomic particles have no definite position until they are measured: the electron orbiting the nucleus of an atom is not the pointlike particle we usually imagine but instead a cloud swathing the nucleus. In the quantum world, a beam of light can behave as a wave or a barrage of particles, depending on how you observe it. Quantities such as the location, momentum, and other characteristics of particles can be described only by probabilities; nothing is certain. “It is often stated that of all the theories proposed in this century, the silliest is quantum theory,” the physicist Michio Kaku wrote in his 1995 book Hyperspace. “In fact, some say that the only thing that quantum theory has going for it is that it is unquestionably correct.

Here in Alpha City, we have a common saying: “What we call ‘sky’ is merely a figment of our narrative.” The most dreamy-eyed among us seem to adorn themselves and their aspirations in that proverb and you’ll see it everywhere: in advertisements on the sides of streetcars and auto-rickshaws, spelled out in studs and rhinestones on designer jackets, emblazoned in the intricate designs of facial tattoos—even painted on city walls by putrid vandals and inspiring street artists. There is something glorious about kneading out into the doughy firmament the depth and breadth of one’s own universe, in rendering the contours of a sky whose limits are predicated only upon the bounds of one’s own imagination. The fact of the matter is that we cannot see the natural sky at all here. It is something like a theoretical mathematical expression: like the square-root of ‘negative one’—certainly it could be said to have a purpose for existing, but to cast eyes upon it, in its natural quantity, would be something akin to casting one’s eyes upon the raw elements comprising our everyday sustenance. How many of us have even borne close witness to the minute chemical compounds that react to lend battery power to our portable electronics? The sky is indeed such a concealed fixture now. It is fair to say that we have purged our memories of its true face and so we can only approximate a canvas and project our desires upon it to our heart’s dearest fancy. The most cynical among us would ostensibly declare it an unavoidable tragedy, but perhaps even these hardened individuals could not remember the naked sky well enough to know if what they were missing was something worthwhile. Perhaps, it’s cynical of me to say so! In any case, we have our searchlights pointed upwards and crisscrossing that expanse of heavens as though to make some sensational and profane joke of ourselves to the surrounding universe. We beam already video images of beauty pageants and dancing contests with smiling mannequins who look like buffoons. And so, the face of space cloaks itself behind our light pollution—in this respect, our mirrored sidewalks and lustrous streets do little to help our cause—and that face remains hidden from us in its jeering ridicule, its mocking laughter at this inexorable farce of human existence.

There was a summer-long gap between me and all the stuff that was supposed to happen next; I now saw, nested within that gap, possibilities without number. Infinite futures. I am a musician on a stage somewhere, my instrument singing in tones so universal that the masses howl their accord in places near and far. Reseda, New York, Japan; or else I escape through a bedroom window three minutes from now and careen through the streets, crazed, lost, locked inside the person in whose image I have remade myself; or I am no one, driving a delivery van carrying boxes of electronics from nowhere to no place, the road empty before me by day, shared by headless headlights after dark, beams increasing briefly and then gone, beyond, somewhere off in the cross-traffic, catchable in the rearview if I dare. I thrive. I fail to thrive. I fall. I rise. Too many. Too late. Not that, not those, not these: this.

due to the precision of the optical electron oscillation frequency within strontium or aluminium. 30. Train of identical nearly single-cycle optical pulses. The spectrum of the pulse train looks like the teeth of a comb, hence it is called a frequency comb. ‘Optical clockwork’ of this kind allows the comparison of disparate frequencies with such remarkable precision that it provides a means to test the tenets of relativity, and thus to understand better the role of light in defining space and time. Frequency, and thus time, is the physical quantity that can be measured with the highest precision of any quantity, by far. Optical telecommunications Frequency combs are also important in telecommunications links based on light. In Chapter 3, I described how optical waves could be guided along a fibre or in a glass ‘chip’. This phenomenon underpins the long-distance telecommunications infrastructure that connects people across different continents and powers the Internet. The reason it is so effective is that light-based communications have much more capacity for carrying information than do electrical wires, or even microwave cellular networks. This makes possible massive data transmission, such as that needed to deliver video on demand over the Internet. Many telecommunications companies offer ‘fibre optic broadband’ deals. A key feature of these packages is the high speed—up to 100 megabytes per second (MBps)—at which data may be received and transmitted. A byte is a number of bits, each of which is a 1 or a 0. Information is sent over fibres as a sequence of ‘bits’, which are decoded by your computer or mobile phone into intelligible video, audio, or text messages. In optical communications, the bits are represented by the intensity of the light beam—typically low intensity is a 0 and higher intensity a 1. The more of these that arrive per second, the faster the communication rate. The MBps speed of the package specifies how rapidly we can transmit and receive information over that company’s link.

Long-Term Results The practical value of the solutions obtained is one way to determine if the subjective reports of accomplishments might be temporary euphoria. The nature of these solutions covered a broad spectrum, including: A new approach to the design of a vibratory microtome A commercial building design, accepted by the client Space-probe experiments devised to measure solar properties Design of a linear electron accelerator beam-steering device An engineering improvement to a magnetic tape recorder A chair design modeled and accepted by the manufacturer A letterhead design approved by the customer A mathematical theorem regarding NOR-gate circuits Completion of a furniture-line design A new conceptual model of a photon found to be useful A design of a private dwelling approved by the client Table 9.3

The CAD image was drawn by an electron beam onto a green phosphorus coating on the inside of the glass TV tube. The

What is Directed Energy Deposition in 3D Printing Directed Energy Deposition (DED) is a term that encompasses technologies involving semi-automated powder spraying and wire welding for manufacturing. When applied to 3D shapes, DED is considered an additive manufacturing process. It typically results in a rougher surface compared to Powder Bed Fusion, due to the larger bead sizes and coarser powder used, which often necessitates additional machining. DED systems generally fall into two categories: deposition systems and hybrid systems that combine a DED head with traditional machining equipment. The main advantages of DED include faster deposition compared to powder bed fusion 3D printing and the ability to create functionally graded material structures, especially when using powder. Additionally, since the feedstock and energy source move together, DED systems can manufacture very large structures, unrestricted by the size limitations of a build box. In some cases, DED can be more effective than traditional manufacturing methods or powder bed fusion. Most DED systems consist of a deposition head that uses either wire or powder and is mounted on a robot or CNC system. Common energy sources include Arc, Laser, or Electron Beam, with lasers being the most frequently used for powder feedstock. The process involves offline programming to generate a tool path from a sliced CAD file. The motion system then follows this path, depositing material in layers to build the desired shape. DED is compatible with a variety of weldable alloys, such as aluminum, steel, nickel, and titanium. Depending on the chosen alloy and process, shielding gas may be applied locally or within an enclosed environment.

WHAT IS POWDER BED FUSION Powder Bed Fusion (PBF) stands as a notable Additive Manufacturing (AM) technique, characterized by its layer-by-layer approach to creating objects. With its potential applications across automotive, aerospace, energy sectors, and household appliances, PBF represents a pivotal future manufacturing method. Alongside PBF, other AM methods like Laminated Object Manufacturing, Direct Energy Deposition, Stereolithography (SLA), and Solid Ground Curing (SGC) contribute to the diverse landscape of additive manufacturing. This overview will focus on the mechanics of the PBF process, particularly highlighting Direct Metal Laser Deposition (DMLS), Selective Laser Sintering (SLS), Selective Laser Melting (SLM), Electron Beam Melting (EBM), and Selective Heat Sintering (SHS). In these techniques, a layer of powder is spread onto a platform, often referred to as the build platform. While SLS, SLM, and DMLS employ lasers as the primary heat source, EBM utilizes an electron beam. SHS, on the other hand, employs a heated thermal head for sintering plastic powders. Among these methods, SLS, DMLS, and SHS are powder-sintering processes, whereas SLM and EBM are powder-melting processes.

The cathode-ray tube (CRT) was a form of analog computer: varying the voltages to the deflection coils varied the path traced by the electron beam. The CRT, especially in its incarnation as an oscilloscope, could be used to add, subtract, multiply, and divide signals—the results being displayed directly as a function of the amplitude of the deflection and its frequency in time. From these analog beginnings, the digital universe took form.

Another calculated that Tesla made at least five outstanding scientific discoveries—cosmic rays, artificial radioactivity, disintegrating beam of electrified particles, electron microscope, and X-rays—that others “rediscovered” up to forty years later and for which they then won Nobel Prizes.

checked his gauge; it was twenty-five feet. His beam had still not reached the bottom. He went down, with the receiver around his neck beeping louder and louder. The ocean around him was noisy. It was something you noticed on a night dive—the sea was alive with night creatures, eating and clicking with a strange, almost mechanical sound, like a giant bank of electronic relays far off.

[W]hereas we might have been content enough to believe that electrons in a bright beam are wave-like and can be diffracted by the double slits, it is hard to understand how one-by-one passage of what seem to be particles (judging from the discrete bright spots that appear on the screen) can produce wave-like interference. We’re forced to conclude that ‘wave-like’ electrons can interfere with themselves.

Passing through every wall are electronic beams that create a shadow play of desire staged by the puppeteers of globalized commerce, who fund their advertising each year with more than a hundred dollars spent for this planet’s every man, woman, child.

It took quantum theory … to reconcile how both ideas could be true: photons and other subatomic particles—electrons, protons, and so forth—exhibit two complementary qualities; they are, as one physicist put it, “wavicles.” To explain the idea … physicists often used a thought experiment, in which Young’s double-slit demonstration is repeated with a beam of electrons instead of light. Obeying the laws of quantum mechanics, the stream of particles would split in two, and the smaller streams would interfere with each other, leaving the same kind of light- and dark-striped pattern as was cast by light. Particles would act like waves.311 In 1961, this idea was actually tested with electrons, and it worked as expected. Elementary particles, chunks of stuff like little billiard balls, behave like waves, provided that you aren’t looking. This can be demonstrated easily even if you shoot a single photon one at a time through a double-slit apparatus.312 However—and this is the frosting on the quantum measurement problem—those very same chunks of stuff behave like particles when you do look at them. Technically, the process of looking is called gaining “which-path” information, in which you learn which path a photon took as it traveled through the double-slit apparatus. To repeat: If you know that it goes through the left slit or the right slit, typically determined using a detector placed behind each slit, then the photon will behave like a particle. But if you don’t know, then it will behave like a wave. Assumptions The experiment we conducted took advantage of this intriguing effect. It was based on two assumptions: (A) If information is gained—by any means—about a photon’s path as it travels through two slits, then the quantum wavelike interference pattern, produced by photons traveling through the slits, will “collapse” in proportion to the certainty of the knowledge obtained. (B) If some aspect of consciousness is a primordial, self-aware feature of the fabric of reality, and that property is modulated by us through capacities we enjoy as attention and intention, then focusing human attention on a double-slit system may extract information about the photon’s path, and in turn that will affect the interference pattern.

I have remade myself; or I am no one, driving a delivery van carrying boxes of electronics from nowhere to no place, the road empty before me by day, shared by headless headlights after dark, beams increasing briefly and then gone, beyond, somewhere off in the cross-traffic, catchable in the rearview if I dare. I thrive. I fail to thrive. I fall. I rise. Too many. Too late. Not that, not those, not these: this.

Einstein described a beam of light as a stream of little particles, each with an energy equal to Planck’s constant multiplied by the frequency of the light wave (the same rule used for Planck’s “oscillators”). Each photon (the name now given to these particles of light) has a fixed amount of energy it can provide, depending on the frequency; and some minimum amount of energy is required to knock an electron loose. If the energy of a single photon is more than the minimum needed, the electron will be knocked loose, and carry the rest of the photon’s energy with it. The higher the frequency, the higher the single photon energy and the more energy the electrons have when they leave, exactly as the experiments show. If the energy of a single photon is lower than the minimum energy for knocking an electron out, nothing happens, explaining the lack of electrons at low frequencies.* Describing light as a particle was a hugely controversial idea in 1905, as it overturned a hundred years’ worth of physics and requires a very different view of light. Rather than a continuous wave, like water poured into a dog’s bowl, light has to be thought of as a stream of discrete particles, like a scoop of kibble poured into a bowl. And yet each of those particles still has a frequency associated with it, and somehow they add up to give an interference pattern, just like a wave.

Es una tecnología de soldadura creada en la NASA y ahora conocida en inglés como EBF3 (Electron Beam Free Form Fabrication). Fue desarrollada para poder imprimir en 3D con metales y aleaciones como titanio, tungsteno, aceros, níquel y otros.

WHAT ABOUT PLAQUE? Okay, so maybe statin drugs don’t cut the risk of dying, except possibly in middle-aged men with previous histories of heart disease (and even then the effect is modest). But what about plaque? Doesn’t aggressive lowering of LDL cholesterol at least reduce plaque? Well, no. A study published in the American Journal of Cardiology in 2003 used electron beam tomography to evaluate plaque in 182 patients after 1.2 years of treatment with either statins alone or statins in conjunction with niacin.32 And yes, just like in many other studies, cholesterol did indeed go down in those patients treated with cholesterol-lowering medication. But plaque? Sorry. The authors wrote, “Despite the greater improvement in [cholesterol numbers] … there were no differences in calcified plaque progression.” In fact, subjects in both groups had—on average—a 9.2 percent increase in plaque buildup. “[W]ith respect to LDL cholesterol lowering, ‘lower is better’ is not supported by changes in calcified plaque progression,” concluded the authors.

Physicist David Bohm (1983) frequently refers to the hologram as a metaphor for a new description of reality, suggesting that the universe is constructed on the same principles as the hologram. The world as perceived by our senses appears on the surface as composed of isolated, separate parts. He refers to this as the “explicate or unfolded order of things.” The basic order, wholeness, and unity of the universe, however, is enfolded into the “implicate order.” The undivided totality of the implicate order is an “energy sea” of electromagnetic waves, electron beams, sound waves, and other energies and resonances, including human consciousness. The brain “lifts” data or mathematically constructs “concrete” reality by interpreting frequencies from that energy sea, a realm beyond time and space.