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107-463: The word 'Photonics' is derived from the Greek word "phos" meaning light (which has genitive case "photos" and in compound words the root "photo-" is used); it appeared in the late 1960s to describe a research field whose goal was to use light to perform functions that traditionally fell within the typical domain of electronics, such as telecommunications, information processing, etc. An early instance of

214-521: A 1 ) , P ( a 2 ) , . . . , P ( a n ) {\displaystyle P(a_{1}),P(a_{2}),...,P(a_{n})} , associated with events a 1 , . . . , a n {\displaystyle a_{1},...,a_{n}} , is defined as: H r ( A ) = 1 1 − r log 2 ⁡ ∑ i = 1 n P r (

321-692: A i ) {\displaystyle H_{r}(A)={1 \over 1-r}\log _{2}\sum _{i=1}^{n}P^{r}(a_{i})} for 0 < r < ∞ {\displaystyle 0<r<\infty } and r ≠ 1 {\displaystyle r\neq 1} . We arrive at the definition of Shannon entropy from Rényi when r → 1 {\displaystyle r\rightarrow 1} , of Hartley entropy (or max-entropy) when r → 0 {\displaystyle r\rightarrow 0} , and min-entropy when r → ∞ {\displaystyle r\rightarrow \infty } . Quantum information theory

428-739: A backlight of either cold cathode fluorescent lamps or, more often today, LEDs. Characteristic for research on semiconductor light sources is the frequent use of III-V semiconductors instead of the classical semiconductors like silicon and germanium . This is due to the special properties of III-V semiconductors that allow for the implementation of light emitting devices . Examples for material systems used are gallium arsenide (GaAs) and aluminium gallium arsenide (AlGaAs) or other compound semiconductors . They are also used in conjunction with silicon to produce hybrid silicon lasers . Light can be transmitted through any transparent medium. Glass fiber or plastic optical fiber can be used to guide

535-459: A harmonic oscillator , quantum information theory is concerned with both continuous-variable systems and finite-dimensional systems. Entropy measures the uncertainty in the state of a physical system. Entropy can be studied from the point of view of both the classical and quantum information theories. Classical information is based on the concepts of information laid out by Claude Shannon . Classical information, in principle, can be stored in

642-461: A Campbell editorial and keep my temper). Damon Knight described Campbell as a "portly, bristled-haired blond man with a challenging stare". "Six-foot-one, with hawklike features, he presented a formidable appearance," said Sam Moskowitz . "He was a tall, large man with light hair, a beaky nose, a wide face with thin lips, and with a cigarette in a holder forever clamped between his teeth", wrote Asimov. Algis Budrys wrote that "John W. Campbell

749-416: A bit of binary strings. Any system having two states is a capable bit. Shannon entropy is the quantification of the information gained by measuring the value of a random variable. Another way of thinking about it is by looking at the uncertainty of a system prior to measurement. As a result, entropy, as pictured by Shannon, can be seen either as a measure of the uncertainty prior to making a measurement or as

856-519: A button hook. You've never stopped hating her for it." Bester commented: "It reinforced my private opinion that a majority of the science-fiction crowd, despite their brilliance, were missing their marbles." Asimov remained grateful for Campbell's early friendship and support. He dedicated The Early Asimov (1972) to him, and concluded it by stating that "There is no way at all to express how much he meant to me and how much he did for me except, perhaps, to write this book evoking, once more, those days of

963-537: A century sooner, with vastly less human misery, and with almost no bloodshed ... The only way slavery has ever been ended, anywhere, is by introducing industry ... If a man is a skilled and competent machinist – if the lathes work well under his hands – the industrial management will be forced, to remain in business, to accept that fact, whether the man be black, white, purple, or polka-dotted. According to Michael Moorcock , Campbell suggested that some people preferred slavery. He also, when faced with

1070-509: A classical computer hence showing that quantum computers should be more powerful than Turing machines. Around the time computer science was making a revolution, so was information theory and communication, through Claude Shannon . Shannon developed two fundamental theorems of information theory: noiseless channel coding theorem and noisy channel coding theorem . He also showed that error correcting codes could be used to protect information being sent. Quantum information theory also followed

1177-412: A different tone using the pseudonym Don A. Stuart, which was derived from his wife's maiden name. He published several stories under this pseudonym, including Twilight ( Astounding , November 1934), Night ( Astounding , October 1935), and Who Goes There? ( Astounding , August 1938). Who Goes There? , about a group of Antarctic researchers who discover a crashed alien vessel, formerly inhabited by

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1284-486: A fascist, the publishers of Analog magazine announced that the John W. Campbell Award for Best New Writer would immediately be renamed to "The Astounding Award for Best New Writer ". The Science Fiction and Fantasy Hall of Fame inducted Campbell in 1996, in its inaugural class of two deceased and two living persons. Campbell and Astounding shared one of the inaugural Hugo Awards with H. L. Gold and Galaxy at

1391-496: A field began with the invention of the maser and laser in 1958 to 1960. Other developments followed: the laser diode in the 1970s, optical fibers for transmitting information, and the erbium-doped fiber amplifier . These inventions formed the basis for the telecommunications revolution of the late 20th century and provided the infrastructure for the Internet . Though coined earlier, the term photonics came into common use in

1498-753: A galactic federation) in January 1940, which was published later that year in the September edition of Astounding Science Fiction . Similarly, Arthur C. Clarke 's " Rescue Party " and Fredric Brown 's " Arena " (basis of the Star Trek episode of the same name ) and " Letter to a Phoenix " (all first appeared in Astounding ) also depicts humans favorably above aliens. Campbell was a critic of government regulation of health and safety, excoriating numerous public health initiatives and regulations. Campbell

1605-465: A group of new writers for the in the July 1939 issue of Astounding . The July issue contained A. E. van Vogt 's first story, "Black Destroyer", and Asimov's early story, "Trends"; August brought Robert A. Heinlein 's first story, " Life-Line ", and the next month Theodore Sturgeon 's first story appeared. Also in 1939, Campbell started the fantasy magazine Unknown (later Unknown Worlds ). Unknown

1712-450: A large collection of atoms as in a superconducting quantum computer . Regardless of the physical implementation, the limits and features of qubits implied by quantum information theory hold as all these systems are mathematically described by the same apparatus of density matrices over the complex numbers . Another important difference with quantum mechanics is that while quantum mechanics often studies infinite-dimensional systems such as

1819-456: A large number of quantum systems. The development of viable single-state manipulation techniques led to increased interest in the field of quantum information and computation. In the 1980s, interest arose in whether it might be possible to use quantum effects to disprove Einstein's theory of relativity . If it were possible to clone an unknown quantum state, it would be possible to use entangled quantum states to transmit information faster than

1926-408: A light source is used to encode information on a light source. Modulation can be achieved by the light source directly. One of the simplest examples is to use a flashlight to send Morse code . Another method is to take the light from a light source and modulate it in an external optical modulator . An additional topic covered by modulation research is the modulation format. On-off keying has been

2033-405: A malevolent shape-changing occupant, was published in Astounding almost a year after Campbell became its editor and it was his last significant piece of fiction, at age 28. It was filmed as The Thing from Another World (1951), The Thing (1982), and again as The Thing (2011). Tremaine hired Campbell to succeed him as the editor of Astounding from its October 1937 issue. Campbell

2140-488: A man, but not like a man") and sometimes asked for stories to match cover paintings he had already bought. Campbell had a strong formative influence on Asimov and eventually became a friend. Asimov credited Campbell with encouraging developments within the field of science fiction field by forgoing conventional plot points and requiring its writers to "understand science and understand people." He also called Campbell "the most powerful force in science fiction ever" and said

2247-500: A measure of information gained after making said measurement. Shannon entropy, written as a functional of a discrete probability distribution, P ( x 1 ) , P ( x 2 ) , . . . , P ( x n ) {\displaystyle P(x_{1}),P(x_{2}),...,P(x_{n})} associated with events x 1 , . . . , x n {\displaystyle x_{1},...,x_{n}} , can be seen as

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2354-542: A novel due to the black main character, and Joe Haldeman in the dedication of Forever Peace , for rejecting a novel due to a female soldier protagonist. British science-fiction novelist Michael Moorcock , as part of his "Starship Stormtroopers" editorial, said Campbell's Astounding and its writers were "wild-eyed paternalists to a man, fierce anti-socialists " with "[stories] full of crew-cut wisecracking, cigar-chewing, competent guys (like Campbell's image of himself)"; they sold magazines because their "work reflected

2461-487: A programmable computer, or Turing machine , he showed that any real-world computation can be translated into an equivalent computation involving a Turing machine. This is known as the Church–Turing thesis . Soon enough, the first computers were made, and computer hardware grew at such a fast pace that the growth, through experience in production, was codified into an empirical relationship called Moore's law . This 'law'

2568-453: A project existed and was aimed at developing nuclear weapons" and the demand was dropped. Campbell was also responsible for the grim and controversial ending of Tom Godwin 's short story " The Cold Equations ". Writer Joe Green recounted that Campbell had rejected Godwin's 'Cold Equations' on three different occasions due to disagreements over the fate of the female protagonist. Between December 11, 1957, and June 13, 1958, Campbell hosted

2675-454: A quarter century ago". His final word on Campbell was that "in the last twenty years of his life, he was only a diminishing shadow of what he had once been." Even Heinlein, perhaps Campbell's most important discovery and a "fast friend", tired of him. Poul Anderson wrote that Campbell "had saved and regenerated science fiction", which had become "the product of hack pulpsters " when he took over Astounding . "By his editorial policies and

2782-474: A qubit contains all of its information. This state is frequently expressed as a vector on the Bloch sphere. This state can be changed by applying linear transformations or quantum gates to them. These unitary transformations are described as rotations on the Bloch sphere. While classical gates correspond to the familiar operations of Boolean logic , quantum gates are physical unitary operators . The study of

2889-445: A similar trajectory, Ben Schumacher in 1995 made an analogue to Shannon's noiseless coding theorem using the qubit . A theory of error-correction also developed, which allows quantum computers to make efficient computations regardless of noise and make reliable communication over noisy quantum channels. Quantum information differs strongly from classical information, epitomized by the bit , in many striking and unfamiliar ways. While

2996-580: A sophisticated Manhattanite , recounted at some length his "one demented meeting" with Campbell, a man he imagined from afar to be "a combination of Bertrand Russell and Ernest Rutherford ". The first thing Campbell said to him was that Freud was dead, destroyed by the new discovery of Dianetics , which, he predicted, would win L. Ron Hubbard the Nobel Peace Prize . Campbell ordered the bemused Bester to "think back. Clear yourself. Remember! You can remember when your mother tried to abort you with

3103-434: A third party to another for use in one-time pad encryption. E91 was made by Artur Ekert in 1991. His scheme uses entangled pairs of photons. These two photons can be created by Alice, Bob, or by a third party including eavesdropper Eve. One of the photons is distributed to Alice and the other to Bob so that each one ends up with one photon from the pair. This scheme relies on two properties of quantum entanglement: B92

3210-496: A way of communicating secretly at long distances using the BB84 quantum cryptographic protocol. The key idea was the use of the fundamental principle of quantum mechanics that observation disturbs the observed, and the introduction of an eavesdropper in a secure communication line will immediately let the two parties trying to communicate know of the presence of the eavesdropper. With the advent of Alan Turing 's revolutionary ideas of

3317-605: A way that it described measurement as well as dynamics. These studies emphasized the philosophical aspects of measurement rather than a quantitative approach to extracting information via measurements. See: Dynamical Pictures In the 1960s, Ruslan Stratonovich , Carl Helstrom and Gordon proposed a formulation of optical communications using quantum mechanics. This was the first historical appearance of quantum information theory. They mainly studied error probabilities and channel capacities for communication. Later, Alexander Holevo obtained an upper bound of communication speed in

Photonics - Misplaced Pages Continue

3424-476: A weekly science fiction radio program called Exploring Tomorrow . Green wrote that Campbell "enjoyed taking the 'devil's advocate' position in almost any area, willing to defend even viewpoints with which he disagreed if that led to a livelier debate". As an example, he wrote: [Campbell] pointed out that the much-maligned 'peculiar institution' of slavery in the American South had in fact provided

3531-599: A writer of space adventure. When in 1934 he began to write stories with a different tone, he wrote as Don A. Stuart. From 1930 until 1937, Campbell was prolific and successful under both names; he stopped writing fiction shortly after he became editor of Astounding in 1937. In his capacity as an editor, Campbell published some of the very earliest work, and helped shape the careers of virtually every important science-fiction author to debut between 1938 and 1946, including Isaac Asimov , Robert A. Heinlein , Theodore Sturgeon , and Arthur C. Clarke . Shortly after his death in 1971,

3638-555: Is a projective trend that states that the number of transistors in an integrated circuit doubles every two years. As transistors began to become smaller and smaller in order to pack more power per surface area, quantum effects started to show up in the electronics resulting in inadvertent interference. This led to the advent of quantum computing, which uses quantum mechanics to design algorithms. At this point, quantum computers showed promise of being much faster than classical computers for certain specific problems. One such example problem

3745-588: Is a simpler version of BB84. The main difference between B92 and BB84: Like the BB84, Alice transmits to Bob a string of photons encoded with randomly chosen bits but this time the bits Alice chooses the bases she must use. Bob still randomly chooses a basis by which to measure but if he chooses the wrong basis, he will not measure anything which is guaranteed by quantum mechanics theories. Bob can simply tell Alice after each bit she sends whether he measured it correctly. The most widely used model in quantum computation

3852-1019: Is largely an extension of classical information theory to quantum systems. Classical information is produced when measurements of quantum systems are made. One interpretation of Shannon entropy was the uncertainty associated with a probability distribution. When we want to describe the information or the uncertainty of a quantum state, the probability distributions are simply replaced by density operators ρ {\displaystyle \rho } : S ( ρ ) ≡ − t r ( ρ   log 2 ⁡   ρ ) = − ∑ i λ i   log 2 ⁡   λ i , {\displaystyle S(\rho )\equiv -\mathrm {tr} (\rho \ \log _{2}\ \rho )=-\sum _{i}\lambda _{i}\ \log _{2}\ \lambda _{i},} where λ i {\displaystyle \lambda _{i}} are

3959-413: Is that it is impossible to copy a quantum key because of the no-cloning theorem . If someone tries to read encoded data, the quantum state being transmitted will change. This could be used to detect eavesdropping. The first quantum key distribution scheme, BB84 , was developed by Charles Bennett and Gilles Brassard in 1984. It is usually explained as a method of securely communicating a private key from

4066-411: Is the quantum circuit , which are based on the quantum bit " qubit ". Qubit is somewhat analogous to the bit in classical computation. Qubits can be in a 1 or 0 quantum state , or they can be in a superposition of the 1 and 0 states. However, when qubits are measured, the result of the measurement is always either a 0 or a 1; the probabilities of these two outcomes depend on the quantum state that

4173-466: Is the research on quantum dot semiconductor optical amplifiers. Photodetectors detect light. Photodetectors range from very fast photodiodes for communications applications over medium speed charge coupled devices ( CCDs ) for digital cameras to very slow solar cells that are used for energy harvesting from sunlight . There are also many other photodetectors based on thermal, chemical , quantum, photoelectric and other effects. Modulation of

4280-423: Is used to connote applied research and development. The term photonics more specifically connotes: The term optoelectronics connotes devices or circuits that comprise both electrical and optical functions, i.e., a thin-film semiconductor device. The term electro-optics came into earlier use and specifically encompasses nonlinear electrical-optical interactions applied, e.g., as bulk crystal modulators such as

4387-651: The Hugo Award for Best Professional Magazine four times. Campbell and Analog won the Hugo Award for Best Professional Magazine yet another four times and Campbell's novella Who Goes There? also won a Hugo Award for Best Novella , bringing his total award count to seventeen. Shortly after Campbell's death, the University of Kansas science fiction program—now the Center for the Study of Science Fiction—established

Photonics - Misplaced Pages Continue

4494-629: The Massachusetts Institute of Technology (MIT), where he was befriended by the mathematician Norbert Wiener (who coined the term cybernetics ) – but he failed German. MIT dismissed him in his junior year in 1931. After two years at Duke University , he graduated with a Bachelor of Science in physics in 1934. Campbell began writing science fiction at age 18 while attending MIT and sold his first stories quickly. From January 1930 to June 1931, Amazing Stories published six of his short stories, one novel, and six letters. Campbell

4601-460: The Pockels cell , but also includes advanced imaging sensors. An important aspect in the modern definition of Photonics is that there is not necessarily a widespread agreement in the perception of the field boundaries. Following a source on optics.org, the response of a query from the publisher of Journal of Optics: A Pure and Applied Physics to the editorial board regarding streamlining the name of

4708-557: The Watts riots of the mid-sixties, seriously proposed and went on to proposing that there were 'natural' slaves who were unhappy if freed. I sat on a panel with him in 1965, as he pointed out that the worker bee when unable to work dies of misery, that the moujiks when freed went to their masters and begged to be enslaved again, that the ideals of the anti-slavers who fought in the Civil War were merely expressions of self-interest and that

4815-516: The emission , transmission, amplification , detection, and modulation of light. Photonics commonly uses semiconductor-based light sources, such as light-emitting diodes (LEDs), superluminescent diodes , and lasers. Other light sources include single photon sources , fluorescent lamps , cathode-ray tubes (CRTs), and plasma screens . Note that while CRTs, plasma screens, and organic light-emitting diode displays generate their own light, liquid crystal displays (LCDs) like TFT screens require

4922-570: The " Dean drive ", a device that supposedly produced thrust in violation of Newton's third law , and the " Hieronymus machine ", which could supposedly amplify psi powers. In 1949, Campbell worked closely with L. Ron Hubbard on the techniques that Hubbard later turned into Dianetics . When Hubbard's therapy failed to find support from the medical community, Campbell published the earliest forms of Dianetics in Astounding . He wrote of L. Ron Hubbard's initial article in Astounding that "[i]t is, I assure you in full and absolute sincerity, one of

5029-430: The "first ten years of his editorship he dominated the field completely." Campbell encouraged Cleve Cartmill to write " Deadline ", a short story by that appeared during the wartime year of 1944, a year before the detonation of the first atomic bomb . As Ben Bova , Campbell's successor as editor at Analog , wrote, it "described the basic facts of how to build an atomic bomb. Cartmill and Campbell worked together on

5136-697: The 1930s, Campbell became interested in Joseph Rhine's theories about ESP (Rhine had already founded the Parapsychology Laboratory at Duke University when Campbell was a student there), and over the following years his growing interest in parapsychology would be reflected in the stories he published when he encouraged the writers to include these topics in their tales, leading to the publication of numerous works about telepathy and other " psionic " abilities. This post-war "psi-boom" has been dated by science fiction scholars to roughly

5243-502: The 1953 World Science Fiction Convention . Subsequently, he won the Hugo Award for Best Professional Magazine seven times to 1965. In 2018, he won a retrospective Hugo Award for Best Editor, Short Form (1943). Quantum information Quantum information is the information of the state of a quantum system . It is the basic entity of study in quantum information theory , and can be manipulated using quantum information processing techniques. Quantum information refers to both

5350-459: The 1980s as fiber-optic data transmission was adopted by telecommunications network operators. At that time, the term was used widely at Bell Laboratories . Its use was confirmed when the IEEE Lasers and Electro-Optics Society established an archival journal named Photonics Technology Letters at the end of the 1980s. During the period leading up to the dot-com crash circa 2001, photonics

5457-400: The 1980s. However, around the same time another avenue started dabbling into quantum information and computation: Cryptography . In a general sense, cryptography is the problem of doing communication or computation involving two or more parties who may not trust one another. Bennett and Brassard developed a communication channel on which it is impossible to eavesdrop without being detected,

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5564-682: The Negro 'Civil Rights' groups". On February 10, 1967, Campbell rejected Samuel R. Delany 's Nova a month before it was ultimately published, with a note and phone call to his agent explaining that he did not feel his readership "would be able to relate to a black main character". All these views were reflected in the depiction of aliens in Astounding / Analog . Throughout his editorship, Campbell demanded that depiction of contact between aliens and humans must favor humans. For example, Campbell accepted Isaac Asimov 's proposal for what would become " Homo Sol " (where humans rejected an invitation to join

5671-685: The Spring 1931 Quarterly . During 1934–35 a serial novel, The Mightiest Machine , ran in Astounding Stories , edited by F. Orlin Tremaine , and several stories featuring lead characters Penton and Blake appeared from late 1936 in Thrilling Wonder Stories , edited by Mort Weisinger . The early work for Amazing established Campbell's reputation as a writer of space adventure. In 1934, he began to publish stories with

5778-574: The USA to endure it a few more years than suffer the truly horrendous costs of the Civil War." In a June 1961 editorial called "Civil War Centennial", Campbell argued that slavery had been a dominant form of human relationships for most of history and that the present was unusual in that anti-slavery cultures dominated the planet. He wrote It's my bet that the South would have been integrated by 1910. The job would have been done – and done right – half

5885-575: The University of Kansas science fiction program established the annual John W. Campbell Memorial Award for Best Science Fiction Novel and also renamed its annual Campbell Conference after him. The World Science Fiction Society established the annual John W. Campbell Award for Best New Writer, since renamed the Astounding Award for Best New Writer . The Science Fiction and Fantasy Hall of Fame inducted Campbell in 1996, in its inaugural class of two deceased and two living persons. John Campbell

5992-552: The ability to work in-situ . John W. Campbell John Wood Campbell Jr. (June 8, 1910 – July 11, 1971) was an American science fiction writer and editor. He was editor of Astounding Science Fiction (later called Analog Science Fiction and Fact ) from late 1937 until his death and was part of the Golden Age of Science Fiction . Campbell wrote super-science space opera under his own name and stories under his primary pseudonym, Don A. Stuart. Campbell also used

6099-447: The above topics and differences comprises quantum information theory. Quantum mechanics is the study of how microscopic physical systems change dynamically in nature. In the field of quantum information theory, the quantum systems studied are abstracted away from any real world counterpart. A qubit might for instance physically be a photon in a linear optical quantum computer , an ion in a trapped ion quantum computer , or it might be

6206-459: The annual John W. Campbell Memorial Award for Best Science Fiction Novel and also renamed after him its annual Campbell Conference. The World Science Fiction Society established the annual John W. Campbell Award for Best New Writer. All three memorials became effective in 1973. However, following Jeannette Ng 's August 2019 acceptance speech of the award for Best New Writer at Worldcon 77 , in which she criticized Campbell's politics and called him

6313-572: The antitobacco alarmists were completely right..." In 1963, Campbell published an angry editorial about Frances Oldham Kelsey who, while at the FDA, refused to permit thalidomide to be sold in the United States. In other essays, Campbell supported crank medicine, arguing that government regulation was more harmful than beneficial and that regulating quackery prevented the use of many possible beneficial medicines ( e.g. , krebiozen ). In

6420-439: The assumption that Alice and Bob have a pre-shared Bell state , dense coding transfers two classical bits from Alice to Bob by using one qubit, again under the same assumption, that Alice and Bob have a pre-shared Bell state. One of the best known applications of quantum cryptography is quantum key distribution which provide a theoretical solution to the security issue of a classical key. The advantage of quantum key distribution

6527-583: The average information associated with this set of events, in units of bits: H ( X ) = H [ P ( x 1 ) , P ( x 2 ) , . . . , P ( x n ) ] = − ∑ i = 1 n P ( x i ) log 2 ⁡ P ( x i ) {\displaystyle H(X)=H[P(x_{1}),P(x_{2}),...,P(x_{n})]=-\sum _{i=1}^{n}P(x_{i})\log _{2}P(x_{i})} This definition of entropy can be used to quantify

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6634-437: The basic unit of classical information is the bit, quantum information deals with qubits . Quantum information can be measured using Von Neumann entropy. Recently, the field of quantum computing has become an active research area because of the possibility to disrupt modern computation, communication, and cryptography . The history of quantum information theory began at the turn of the 20th century when classical physics

6741-497: The blacks brought there with a higher standard of living than they had in Africa ;... I suspected, from comments by Asimov, among others – and some Analog editorials I had read – that John held some racist views, at least in regard to blacks. Finally, however, Green agreed with Campbell that "rapidly increasing mechanization after 1850 would have soon rendered slavery obsolete anyhow. It would have been better for

6848-622: The blacks were 'against' emancipation, which was fundamentally why they were indulging in 'leaderless' riots in the suburbs of Los Angeles. By the 1960s, Campbell began to publish controversial essays supporting segregation and other remarks and writings surrounding slavery and race, which distance him from many in the science fiction community. In 1963, Campbell published an essay supporting segregated schools and arguing that "the Negro race" had failed to "produce super-high-geniuses". In 1965, he continued his defense of segregation and related practices, critiquing "the arrogant defiance of law by many of

6955-457: The commonly used modulation format in optical communications. In the last years more advanced modulation formats like phase-shift keying or even orthogonal frequency-division multiplexing have been investigated to counteract effects like dispersion that degrade the quality of the transmitted signal. Photonics also includes research on photonic systems. This term is often used for optical communication systems. This area of research focuses on

7062-460: The connection to lung cancer was "esoteric" and referred to "a barely determinable possible correlation between cigarette smoking and cancer". He said that tobacco's calming effects led to more effective thinking. In a one-page piece about automobile safety in Analog dated May 1967, Campbell wrote of "people suddenly becoming conscious of the fact that cars kill more people than cigarettes do, even if

7169-473: The deep-seated conservatism of the majority of their readers, who saw a Bolshevik menace in every union meeting". He viewed Campbell as turning the magazine into a vessel for right-wing politics , "by the early 1950s ... a crypto-fascist deeply philistine magazine pretending to intellectualism and offering idealistic kids an 'alternative' that was, of course, no alternative at all". SF writer Alfred Bester , an editor of Holiday Magazine and

7276-399: The discovery that light is quantized, when Albert Einstein famously explained the photoelectric effect in 1905. Optics tools include the refracting lens , the reflecting mirror , and various optical components and instruments developed throughout the 15th to 19th centuries. Key tenets of classical optics, such as Huygens Principle , developed in the 17th century, Maxwell's Equations and

7383-678: The eigenvalues of ρ {\displaystyle \rho } . Von Neumann entropy plays a role in quantum information similar to the role Shannon entropy plays in classical information. Quantum communication is one of the applications of quantum physics and quantum information. There are some famous theorems such as the no-cloning theorem that illustrate some important properties in quantum communication. Dense coding and quantum teleportation are also applications of quantum communication. They are two opposite ways to communicate using qubits. While teleportation transfers one qubit from Alice and Bob by communicating two classical bits under

7490-723: The first transistor was invented in 1948, the unique applications of photonics continue to emerge. Economically important applications for semiconductor photonic devices include optical data recording, fiber optic telecommunications, laser printing (based on xerography), displays, and optical pumping of high-power lasers. The potential applications of photonics are virtually unlimited and include chemical synthesis, medical diagnostics, on-chip data communication, sensors, laser defense, and fusion energy , to name several interesting additional examples. Microphotonics and nanophotonics usually includes photonic crystals and solid state devices . The science of photonics includes investigation of

7597-532: The first to achieve commercial success; PICs based on silicon wafer substrates are now also a commercialized technology. Key Applications for Integrated Photonics include: Biophotonics employs tools from the field of photonics to the study of biology . Biophotonics mainly focuses on improving medical diagnostic abilities (for example for cancer or infectious diseases) but can also be used for environmental or other applications. The main advantages of this approach are speed of analysis, non-invasive diagnostics, and

7704-622: The fundamental unit of classical information is the bit , the most basic unit of quantum information is the qubit . Classical information is measured using Shannon entropy , while the quantum mechanical analogue is Von Neumann entropy . Given a statistical ensemble of quantum mechanical systems with the density matrix ρ {\displaystyle \rho } , it is given by S ( ρ ) = − Tr ⁡ ( ρ ln ⁡ ρ ) . {\displaystyle S(\rho )=-\operatorname {Tr} (\rho \ln \rho ).} Many of

7811-483: The help and encouragement he gave his writers (always behind the scenes), he raised both the literary and the intellectual standard anew. Whatever progress has been made stems from that renaissance". Campbell and Astounding shared one of the inaugural Hugo Awards with H. L. Gold and Galaxy at the 1953 World Science Fiction Convention . Subsequently, Campbell and Astounding won the Hugo Award for Best Professional Editor seven additional times as well as winning

7918-450: The implementation of photonic systems like high speed photonic networks. This also includes research on optical regenerators , which improve optical signal quality. Photonic integrated circuits (PICs) are optically active integrated semiconductor photonic devices. The leading commercial application of PICs are optical transceivers for data center optical networks. PICs fabricated on III-V indium phosphide semiconductor wafer substrates were

8025-565: The journal reported significant differences in the way the terms "optics" and "photonics" describe the subject area, with some description proposing that "photonics embraces optics". In practice, as the field evolves, evidences that "modern optics" and Photonics are often used interchangeably are very diffused and absorbed in the scientific jargon. Photonics also relates to the emerging science of quantum information and quantum optics. Other emerging fields include: Applications of photonics are ubiquitous. Included are all areas from everyday life to

8132-760: The light along a desired path. In optical communications optical fibers allow for transmission distances of more than 100 km without amplification depending on the bit rate and modulation format used for transmission. A very advanced research topic within photonics is the investigation and fabrication of special structures and "materials" with engineered optical properties. These include photonic crystals , photonic crystal fibers and metamaterials . Optical amplifiers are used to amplify an optical signal. Optical amplifiers used in optical communications are erbium-doped fiber amplifiers , semiconductor optical amplifiers , Raman amplifiers and optical parametric amplifiers . A very advanced research topic on optical amplifiers

8239-474: The men he had trained (including me) in doing so, but felt it was his duty to stir up the minds of his readers and force curiosity right out to the border lines. He began a series of editorials ... in which he championed a social point of view that could sometimes be described as far right (he expressed sympathy for George Wallace in the 1968 national election, for instance). There was bitter opposition to this from many (including me – I could hardly ever read

8346-494: The microscopic level, quantum information science focuses on extracting information from those properties, and quantum computation manipulates and processes information – performs logical operations – using quantum information processing techniques. Quantum information, like classical information, can be processed using digital computers , transmitted from one location to another, manipulated with algorithms , and analyzed with computer science and mathematics . Just like

8453-409: The microscopic scale. Observation in science is one of the most important ways of acquiring information and measurement is required in order to quantify the observation, making this crucial to the scientific method . In quantum mechanics , due to the uncertainty principle , non-commuting observables cannot be precisely measured simultaneously, as an eigenstate in one basis is not an eigenstate in

8560-543: The mid-1950s to the early 1960s, and continues to influence many popular culture tropes and motifs. Campbell rejected the Shaver Mystery in which the author claimed to have had a personal experience with a sinister ancient civilization that harbored fantastic technology in caverns under the earth. His increasing beliefs in pseudoscience would eventually start to isolate and alienate him from some of his writers, including Asimov. He wrote favorably about such things as

8667-528: The most advanced science, e.g. light detection, telecommunications , information processing , photovoltaics , photonic computing , lighting , metrology , spectroscopy , holography , medicine (surgery, vision correction, endoscopy, health monitoring), biophotonics , military technology , laser material processing, art diagnostics (involving InfraRed Reflectography, Xrays , UltraViolet fluorescence, XRF ), agriculture , and robotics . Just as applications of electronics have expanded dramatically since

8774-497: The most important articles ever published." Campbell continued to promote Hubbard's theories until 1952, when the pair split acrimoniously over the direction of the movement. Asimov wrote: "A number of writers wrote pseudoscientific stuff to ensure sales to Campbell, but the best writers retreated, I among them. ..." Elsewhere Asimov went on to further explain Campbell championed far-out ideas ... He pained very many of

8881-506: The other basis. According to the eigenstate–eigenvalue link, an observable is well-defined (definite) when the state of the system is an eigenstate of the observable. Since any two non-commuting observables are not simultaneously well-defined, a quantum state can never contain definitive information about both non-commuting observables. Data can be encoded into the quantum state of a quantum system as quantum information . While quantum mechanics deals with examining properties of matter at

8988-448: The pen names Karl Van Kampen and Arthur McCann. His novella Who Goes There? was adapted as the films The Thing from Another World (1951), The Thing (1982), and The Thing (2011). Campbell began writing science fiction at age 18 while attending MIT . He published six short stories, one novel, and eight letters in the science fiction magazine Amazing Stories from 1930 to 1931. This work established Campbell's reputation as

9095-403: The physical resources required to store the output of an information source. The ways of interpreting Shannon entropy discussed above are usually only meaningful when the number of samples of an experiment is large. The Rényi entropy is a generalization of Shannon entropy defined above. The Rényi entropy of order r, written as a function of a discrete probability distribution, P (

9202-409: The pulp mire and start writing intelligently, for adults". After 1950, new magazines such as Galaxy Science Fiction and The Magazine of Fantasy & Science Fiction moved in different directions and developed talented new writers who were not directly influenced by him. Campbell often suggested story ideas to writers (including "Write me a creature that thinks as well as a man, or better than

9309-448: The qubit state being continuous-valued, it is impossible to measure the value precisely. Five famous theorems describe the limits on manipulation of quantum information. These theorems are proven from unitarity , which according to Leonard Susskind is the technical term for the statement that quantum information within the universe is conserved. The five theorems open possibilities in quantum information processing. The state of

9416-445: The qubits were in immediately prior to the measurement. Any quantum computation algorithm can be represented as a network of quantum logic gates . If a quantum system were perfectly isolated, it would maintain coherence perfectly, but it would be impossible to test the entire system. If it is not perfectly isolated, for example during a measurement, coherence is shared with the environment and appears to be lost with time; this process

9523-477: The same entropy measures in classical information theory can also be generalized to the quantum case, such as Holevo entropy and the conditional quantum entropy . Unlike classical digital states (which are discrete), a qubit is continuous-valued, describable by a direction on the Bloch sphere . Despite being continuously valued in this way, a qubit is the smallest possible unit of quantum information, and despite

9630-403: The speed of light, disproving Einstein's theory. However, the no-cloning theorem showed that such cloning is impossible. The theorem was one of the earliest results of quantum information theory. Despite all the excitement and interest over studying isolated quantum systems and trying to find a way to circumvent the theory of relativity, research in quantum information theory became stagnant in

9737-488: The story, drawing their scientific information from papers published in the technical journals before the war. To them, the mechanics of constructing a uranium-fission bomb seemed perfectly obvious." The FBI descended on Campbell's office after the story appeared in print and demanded that the issue be removed from the newsstands. Campbell convinced them that by removing the magazine "the FBI would be advertising to everyone that such

9844-428: The technical definition in terms of Von Neumann entropy and the general computational term. It is an interdisciplinary field that involves quantum mechanics , computer science , information theory , philosophy and cryptography among other fields. Its study is also relevant to disciplines such as cognitive science , psychology and neuroscience . Its main focus is in extracting information from matter at

9951-444: The transmission of a classical message via a quantum channel . In the 1970s, techniques for manipulating single-atom quantum states, such as the atom trap and the scanning tunneling microscope , began to be developed, making it possible to isolate single atoms and arrange them in arrays. Prior to these developments, precise control over single quantum systems was not possible, and experiments used coarser, simultaneous control over

10058-402: The wave equations, developed in the 19th, do not depend on quantum properties of light. Photonics is related to quantum optics , optomechanics , electro-optics , optoelectronics and quantum electronics . However, each area has slightly different connotations by scientific and government communities and in the marketplace. Quantum optics often connotes fundamental research, whereas photonics

10165-461: The word was in a December 1954 letter from John W. Campbell to Gotthard Gunther : Incidentally, I’ve decided to invent a new science — photonics. It bears the same relationship to Optics that electronics does to electrical engineering. Photonics, like electronics, will deal with the individual units; optics and EE deal with the group-phenomena! And note that you can do things with electronics that are impossible in electrical engineering! Photonics as

10272-452: Was a field focused largely on optical telecommunications. However, photonics covers a huge range of science and technology applications, including laser manufacturing, biological and chemical sensing, medical diagnostics and therapy, display technology, and optical computing . Further growth of photonics is likely if current silicon photonics developments are successful. Photonics is closely related to optics . Classical optics long preceded

10379-508: Was a heavy smoker throughout his life and was seldom seen without his customary cigarette holder. In the Analog of September 1964, nine months after the Surgeon General 's first major warning about the dangers of cigarette smoking had been issued (January 11, 1964) Campbell ran an editorial, "A Counterblaste to Tobacco" that took its title from the anti-smoking book of the same name by King James I of England . In it, he stated that

10486-522: Was an atheist. Editor T. O'Conor Sloane lost Campbell's first manuscript that he accepted for Amazing Stories , entitled "Invaders of the Infinite". "When the Atoms Failed" appeared in January 1930, followed by five more during 1930. Three were part of a space opera series featuring the characters Arcot, Morey, and Wade. A complete novel in the series, Islands of Space , was the cover story in

10593-631: Was born in Newark, New Jersey , in 1910. His father, John Wood Campbell Sr., was an electrical engineer. His mother, Dorothy (née Strahern) had an identical twin who visited them often. John was unable to tell them apart and said he was frequently rebuffed by the person he took to be his mother. Campbell attended the Blair Academy , a boarding school in rural Warren County , New Jersey, but did not graduate because of lack of credits for French and trigonometry . He also attended, without graduating,

10700-461: Was born. Quantum mechanics was formulated by Erwin Schrödinger using wave mechanics and Werner Heisenberg using matrix mechanics . The equivalence of these methods was proven later. Their formulations described the dynamics of microscopic systems but had several unsatisfactory aspects in describing measurement processes. Von Neumann formulated quantum theory using operator algebra in

10807-785: Was canceled after four years due to wartime paper shortages. Campbell died in 1971 at the age of 61 in Mountainside, New Jersey . At the time of his sudden death after 34 years at the helm of Analog, Campbell's personality and editorial demands had alienated some of his writers to the point that they no longer submitted works to him. One of his writers, Theodore Sturgeon, opted to publish most of his works after 1950 and only submitted one story with Astounding during that same timeframe. The Encyclopedia of Science Fiction wrote: "More than any other individual, he helped to shape modern sf", and Darrell Schweitzer credits him with having "decreed that SF writers should pull themselves up out of

10914-462: Was developed by David Deutsch and Richard Jozsa , known as the Deutsch–Jozsa algorithm . This problem however held little to no practical applications. Peter Shor in 1994 came up with a very important and practical problem , one of finding the prime factors of an integer. The discrete logarithm problem as it was called, could theoretically be solved efficiently on a quantum computer but not on

11021-697: Was editor of Astounding Science Fiction (later called Analog Science Fiction and Fact ) from late 1937 until his death. He stopped writing fiction after he became the editor of Astounding . Between December 11, 1957, and June 13, 1958, he hosted a weekly science fiction radio program called Exploring Tomorrow . The scripts were written by authors such as Gordon R. Dickson and Robert Silverberg . Campbell and Doña Stewart married in 1931. They divorced in 1949, and he married Margaret (Peg) Winter in 1950. He spent most of his life in New Jersey and died of heart failure at his home in Mountainside, New Jersey . He

11128-465: Was not given full authority for Astounding until May 1938, but had been responsible for buying stories earlier. He began to make changes almost immediately, instigating a "mutant" label for unusual stories, and in March 1938, changing the title from Astounding Stories to Astounding Science-Fiction . Lester del Rey 's first story in March 1938 was an early find for Campbell. In 1939, he published

11235-417: Was revolutionized into quantum physics . The theories of classical physics were predicting absurdities such as the ultraviolet catastrophe , or electrons spiraling into the nucleus. At first these problems were brushed aside by adding ad hoc hypotheses to classical physics. Soon, it became apparent that a new theory must be created in order to make sense of these absurdities, and the theory of quantum mechanics

11342-517: Was so unpleasant to me that I was unwilling to face it. Campbell talked a good deal more than he listened, and he liked to say outrageous things." British novelist and critic Kingsley Amis dismissed Campbell brusquely: "I might just add as a sociological note that the editor of Astounding, himself a deviant figure of marked ferocity, seems to think he has invented a psi machine." Several science-fiction novelists have criticized Campbell as prejudiced – Samuel R. Delany for Campbell's rejection of

11449-415: Was the greatest editor SF has seen or is likely to see, and is in fact one of the major editors in all English-language literature in the middle years of the twentieth century. All about you is the heritage of what he built". Asimov said that Campbell was "talkative, opinionated, quicksilver-minded, overbearing. Talking to him meant listening to a monologue..." Knight agreed: "Campbell's lecture-room manner

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