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Minimoog

The Minimoog is an analog synthesizer first manufactured by Moog Music between 1970 and 1981. Designed as a more affordable, portable version of the modular Moog synthesizer, it was the first synthesizer sold in retail stores. It was first popular with progressive rock and jazz musicians and found wide use in disco, pop, rock and electronic music.

Production of the Minimoog stopped in the early 1980s after the sale of Moog Music. In 2002, founder Robert Moog regained the rights to the Moog brand, bought the company, and released an updated version of the Minimoog, the Minimoog Voyager. In 2016 and in 2022, Moog Music released another new version of the original Minimoog.

Development
In the 1960s, RA Moog Co manufactured Moog synthesizers, which helped bring electronic sounds to music but remained inaccessible to ordinary people. These modular synthesizers were difficult to use and required users to connect components manually with patch cables to create sounds. They were also sensitive to temperature and humidity, and cost tens of thousands of dollars. Most were owned by universities or record labels, and used to create soundtracks or jingles; by 1970, only 28 were owned by musicians.

Hoping to create a smaller, more reliable synthesizer, Moog engineer Bill Hemsath created a prototype by sawing a keyboard in half and wiring several components into a small cabinet. Moog president Robert Moog felt the prototype was fun, but did not initially see a market for it. Moog and the engineers created several more prototypes, adding features such as the suitcase design to aid portability.

In early 1970, Moog Co began losing money as interest in its modular synthesizers fell. Fearing they would lose their jobs if the company closed, the engineers developed a version of Hemsath's miniature synthesizer, the Minimoog Model D, while Moog was away. Moog chastised them, but came to see the potential in the Model D and authorized its production.

As the engineers could not properly stabilize the power supply, the Minimoog's three oscillators were never completely synchronized. Although unintentional, this created the synthesizer's "warm, rich" sound. Its voltage-controlled filter was unique, allowing users to shape sounds to create "everything from blistering, funky bass blurps ... to spacey whistle lead tones". The Minimoog also was the first synthesizer to feature a pitch wheel, which allows players to bend notes as a guitarist or saxophonist does, allowing for more expressive playing. Moog's associate David Borden felt that Moog would have become extremely wealthy had he patented the pitch wheel.

Release
Moog Co released the first Minimoog in 1970. Moog said it was conceived as a portable tool for session musicians, and the team expected to sell "maybe 100 of them". Moog became acquainted with former evangelist and musician David Van Koevering, who was so impressed with the Minimoog that he began demonstrating it to musicians and music stores. Van Koevering's friend Glen Bell, founder of the restaurant chain Taco Bell, allowed him to use a building on a private island Bell owned in Florida. There, Van Koevering hosted an event he billed as Island of Electronicus, a "pseudo-psychedelic experience that brought counterculture (minus the drugs) to straight families and connected it with the sound of the Minimoog".

The Minimoog was in continuous production for 13 years and over 12,000 were made. It was the first synthesizer sold in retail stores. Despite the success, Moog Co could not afford to meet demand, nor had credit for a loan, and Moog sold the company to Bill Waytena, a venture capitalist, in 1971. Van Koevering was hired as head of sales and marketing, expanding the sales of the Minimoog worldwide. Production of the Minimoog stopped in 1981 and Moog Co ceased all production in 1993.

Later models
In the 1980s, the rights to use the Moog Music name in the United Kingdom were purchased by Alex Winter of Caerphilly, Wales, who commenced limited production of an updated Minimoog in 1998 as the Moog Minimoog 204E. The 204E added pulse width modulation and MIDI to the Model D specification. In 2002, Robert Moog reacquired the rights to the Moog name and bought the company. In 2002, Moog Co released the Minimoog Voyager, an updated version of the Minimoog that sold more than 14,000 units, more than the original Minimoog. Although the Welsh incarnation of Moog Music went into administration shortly afterwards, Winter retained the rights to the Moog name in the UK, with the result that the Minimoog Voyager was launched there as the Voyager by Bob Moog.

In 2016, Moog Music began manufacturing an updated version of the Model D, with an independent LFO and MIDI, and an aftertouch and velocity-sensitive keyboard. Production ended around August 2017, after a little under a year. In 2018, Moog Music released the Minimoog Model D app for iOS. In 2022, after being out of production for over five years, the Model D was reissued a third time. The basic architecture remained the same as the previous version, but also included new features like a spring-loaded pitch-bend wheel and updates to the previous unit's MIDI specs.

Impact
According to TJ Pinch, author of Analog Days, the Minimoog was the first synthesizer to become a "classic". Wired described it as "the most famous synthesizer in music history ... a ubiquitous analog keyboard that can be heard in countless pop, rock, hip-hop, and techno tracks from the 1970s, 80s, and 90s". It was also important for its portability. David Borden, an associate of Moog, said that the Minimoog "took the synthesizer out of the studio and put it into the concert hall". According to the Guardian, "Tweaked now so that the synthesizer could reliably perform as either a melodic lead or propulsive bass instrument (rather than just as a complex sound-generating machine), the Minimoog changed everything ... the Moogs oozed character. Their sound could be quirky, kitsch and cute, or pulverising, but it was always identifiable as Moog."

The Minimoog changed the dynamics of rock bands. For the first time, keyboardists could play solos in the style of lead guitarists, or play synthesized basslines. Yes keyboardist Rick Wakeman said: "For the first time you could go on [stage] and give the guitarist a run for his money... A guitarist would say, 'Oh shoot, he's got a Minimoog,' so they're looking for eleven on their volume control - it's the only way they can compete." Wakeman said the instrument "absolutely changed the face of music".

The Minimoog took a place in mainstream black music, most notably in the work of Stevie Wonder. Its use for basslines became particularly popular in funk, as in the Parliament track "Flash Light". It was also popular in jazz, and Sun Ra became perhaps the first musician to perform and record with the instrument (on his 1970 album My Brother the Wind). Herbie Hancock, Dick Hyman and Chick Corea were other early adopters.

The Minimoog became a staple of progressive rock. In the early 1970s, Keith Emerson of Emerson, Lake & Palmer added the Minimoog to his modular 'Monster Moog' as an occasional part of his performances. Wakeman used five Minimoogs on stage so he could play different sounds without having to reconfigure them. It was also used by electronic artists such as Kraftwerk, who used it on their albums Autobahn (1974) and The Man-Machine (1978), and later by Tangerine Dream, Klaus Schulze, and Gary Numan. In the late 1970s and the early 1980s, it was widely used in the emerging disco genre by artists including ABBA and Giorgio Moroder.

In 2012, to celebrate Bob Moog's birthday, Google created an interactive Minimoog softsynth web application as its Google Doodle.

title: Minimoog


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Poly(methyl methacrylate)

Poly(methyl methacrylate) (PMMA) is the synthetic polymer derived from methyl methacrylate. It is used as an engineering plastic, and it is a transparent thermoplastic. PMMA is also known as acrylic, acrylic glass, as well as by the trade names and brands Crylux, Hesalite, Plexiglas, Acrylite, Lucite, and Perspex, among several others (see below). This plastic is often used in sheet form as a lightweight or shatter-resistant alternative to glass. It can also be used as a casting resin, in inks and coatings, and for many other purposes.

It is often technically classified as a type of glass, in that it is a non-crystalline vitreous substance—hence its occasional historic designation as acrylic glass.

History
The first acrylic acid was created in 1843. Methacrylic acid, derived from acrylic acid, was formulated in 1865. The reaction between methacrylic acid and methanol results in the ester methyl methacrylate.

It was developed in 1928 in several different laboratories by many chemists, such as William R. Conn, Otto Röhm, and Walter Bauer, and first brought to market in 1933 by German Röhm & Haas AG (as of January 2019, part of Evonik Industries) and its partner and former U.S. affiliate Rohm and Haas Company under the trademark Plexiglas.

Polymethyl methacrylate was discovered in the early 1930s by British chemists Rowland Hill and John Crawford at Imperial Chemical Industries (ICI) in the United Kingdom. ICI registered the product under the trademark Perspex. About the same time, chemist and industrialist Otto Röhm of Röhm and Haas AG in Germany attempted to produce safety glass by polymerizing methyl methacrylate between two layers of glass. The polymer separated from the glass as a clear plastic sheet, which Röhm gave the trademarked name Plexiglas in 1933. Both Perspex and Plexiglas were commercialized in the late 1930s. In the United States, E.I. du Pont de Nemours & Company (now DuPont Company) subsequently introduced its own product under the trademark Lucite. In 1936 ICI Acrylics (now Lucite International) began the first commercially viable production of acrylic safety glass. During World War II both Allied and Axis forces used acrylic glass for submarine periscopes and aircraft windscreen, canopies, and gun turrets. Scraps of acrylic were also used to made clear pistol grips for the M1911A1 pistol or clear handle grips for the M1 bayonet or theater knifes so that soldiers could put small photos of loved ones or pin-up girls' pictures inside. The were called "Sweetheart Grips" or "Pin-up Grips". Others were used to make handles for theater knives made from scrap materials and people who made them got artistic or creative. Civilian applications followed after the war.

Names
Common orthographic stylings include polymethyl methacrylate and polymethylmethacrylate. The full IUPAC chemical name is poly(methyl 2-methylpropoate). (It is a common mistake to use "an" instead of "en".)

Although PMMA is often called simply "acrylic", acrylic can also refer to other polymers or copolymers containing polyacrylonitrile. Notable trade names and brands include Acrylite, Altuglas, Astariglas, Cho Chen, Crystallite, Cyrolite, Hesalite (when used in Omega watches), Lucite, Optix, Oroglas, PerClax, Perspex, Plexiglas, R-Cast, and Sumipex.

PMMA is an economical alternative to polycarbonate (PC) when tensile strength, flexural strength, transparency, polishability, and UV tolerance are more important than impact strength, chemical resistance, and heat resistance. Additionally, PMMA does not contain the potentially harmful bisphenol-A subunits found in polycarbonate and is a far better choice for laser cutting. It is often preferred because of its moderate properties, easy handling and processing, and low cost. Non-modified PMMA behaves in a brittle manner when under load, especially under an impact force, and is more prone to scratching than conventional inorganic glass, but modified PMMA is sometimes able to achieve high scratch and impact resistance.

Properties

PMMA is a strong, tough, and lightweight material. It has a density of 1.17–1.20 g/cm$3$, which is less than half that of glass. It also has good impact strength, higher than both glass and polystyrene, but significantly lower than polycarbonate and some engineered polymers. PMMA ignites at 460 C and burns, forming carbon dioxide, water, carbon monoxide, and low-molecular-weight compounds, including formaldehyde.

PMMA transmits up to 92% of visible light (3 mm thickness), and gives a reflection of about 4% from each of its surfaces due to its refractive index (1.4905 at 589.3nm). It filters ultraviolet (UV) light at wavelengths below about 300 nm (similar to ordinary window glass). Some manufacturers add coatings or additives to PMMA to improve absorption in the 300–400 nm range. PMMA passes infrared light of up to 2,800 nm and blocks IR of longer wavelengths up to 25,000 nm. Colored PMMA varieties allow specific IR wavelengths to pass while blocking visible light (for remote control or heat sensor applications, for example).

PMMA swells and dissolves in many organic solvents; it also has poor resistance to many other chemicals due to its easily hydrolyzed ester groups. Nevertheless, its environmental stability is superior to most other plastics such as polystyrene and polyethylene, and therefore it is often the material of choice for outdoor applications.

PMMA has a maximum water absorption ratio of 0.3–0.4% by weight. Tensile strength decreases with increased water absorption. Its coefficient of thermal expansion is relatively high at (5–10)×10$−6$ °C$3$.

The Futuro house was made of fibreglass-reinforced polyester plastic, polyester-polyurethane, and poly(methylmethacrylate); one of them was found to be degrading by cyanobacteria and Archaea.

PMMA can be joined using cyanoacrylate cement (commonly known as superglue), with heat (welding), or by using chlorinated solvents such as dichloromethane or trichloromethane (chloroform) to dissolve the plastic at the joint, which then fuses and sets, forming an almost invisible weld. Scratches may easily be removed by polishing or by heating the surface of the material. Laser cutting may be used to form intricate designs from PMMA sheets. PMMA vaporizes to gaseous compounds (including its monomers) upon laser cutting, so a very clean cut is made, and cutting is performed very easily. However, the pulsed lasercutting introduces high internal stresses, which on exposure to solvents produce undesirable "stress-crazing" at the cut edge and several millimetres deep. Even ammonium-based glass-cleaner and almost everything short of soap-and-water produces similar undesirable crazing, sometimes over the entire surface of the cut parts, at great distances from the stressed edge. Annealing the PMMA sheet/parts is therefore an obligatory post-processing step when intending to chemically bond lasercut parts together.

In the majority of applications, PMMA will not shatter. Rather, it breaks into large dull pieces. Since PMMA is softer and more easily scratched than glass, scratch-resistant coatings are often added to PMMA sheets to protect it (as well as possible other functions).

Pure poly(methyl methacrylate) homopolymer is rarely sold as an end product, since it is not optimized for most applications. Rather, modified formulations with varying amounts of other comonomers, additives, and fillers are created for uses where specific properties are required. For example:

 * A small amount of acrylate comonomers are routinely used in PMMA grades destined for heat processing, since this stabilizes the polymer to depolymerization ("unzipping") during processing.
 * Comonomers such as butyl acrylate are often added to improve impact strength.
 * Comonomers such as methacrylic acid can be added to increase the glass transition temperature of the polymer for higher temperature use such as in lighting applications.
 * Plasticizers may be added to improve processing properties, lower the glass transition temperature, improve impact properties, and improve mechanical properties such as elastic modulus
 * Dyes may be added to give color for decorative applications, or to protect against (or filter) UV light.
 * Fillers may be substituted to reduce cost.

Synthesis and processing
PMMA is routinely produced by emulsion polymerization, solution polymerization, and bulk polymerization. Generally, radical initiation is used (including living polymerization methods), but anionic polymerization of PMMA can also be performed.

The glass transition temperature (T$−5$) of atactic PMMA is 105 C. The T$−1$ values of commercial grades of PMMA range from 85 to 165 C; the range is so wide because of the vast number of commercial compositions that are copolymers with co-monomers other than methyl methacrylate. PMMA is thus an organic glass at room temperature; i.e., it is below its T$g$. The forming temperature starts at the glass transition temperature and goes up from there. All common molding processes may be used, including injection molding, compression molding, and extrusion. The highest quality PMMA sheets are produced by cell casting, but in this case, the polymerization and molding steps occur concurrently. The strength of the material is higher than molding grades owing to its extremely high molecular mass. Rubber toughening has been used to increase the toughness of PMMA to overcome its brittle behavior in response to applied loads.

Applications

Being transparent and durable, PMMA is a versatile material and has been used in a wide range of fields and applications such as rear-lights and instrument clusters for vehicles, appliances, and lenses for glasses. PMMA in the form of sheets affords to shatter resistant panels for building windows, skylights, bulletproof security barriers, signs and displays, sanitary ware (bathtubs), LCD screens, furniture and many other applications. It is also used for coating polymers based on MMA provides outstanding stability against environmental conditions with reduced emission of VOC. Methacrylate polymers are used extensively in medical and dental applications where purity and stability are critical to performance.

Glass substitute

 * PMMA is commonly used for constructing residential and commercial aquariums. Designers started building large aquariums when poly(methyl methacrylate) could be used. It is less often used in other building types due to incidents such as the Summerland disaster.
 * PMMA is used for viewing ports and even complete pressure hulls of submersibles, such as the Alicia submarine's viewing sphere and the window of the bathyscaphe Trieste.
 * PMMA is used in the lenses of exterior lights of automobiles.
 * Spectator protection in ice hockey rinks is made from PMMA.
 * Historically, PMMA was an important improvement in the design of aircraft windows, making possible such designs as the bombardier's transparent nose compartment in the Boeing B-17 Flying Fortress. Modern aircraft transparencies often use stretched acrylic plies.
 * Police vehicles for riot control often have the regular glass replaced with PMMA to protect the occupants from thrown objects.
 * PMMA is an important material in the making of certain lighthouse lenses.
 * PMMA was used for the roofing of the compound in the Olympic Park for the 1972 Summer Olympics in Munich. It enabled a light and translucent construction of the structure.
 * PMMA (under the brand name "Lucite") was used for the ceiling of the Houston Astrodome.

Daylight redirection

 * Laser cut acrylic panels have been used to redirect sunlight into a light pipe or tubular skylight and, from there, to spread it into a room. Their developers Veronica Garcia Hansen, Ken Yeang, and Ian Edmonds were awarded the Far East Economic Review Innovation Award in bronze for this technology in 2003.
 * Attenuation being quite strong for distances over one meter (more than 90% intensity loss for a 3000 K source), acrylic broadband light guides are then dedicated mostly to decorative uses.
 * Pairs of acrylic sheets with a layer of microreplicated prisms between the sheets can have reflective and refractive properties that let them redirect part of incoming sunlight in dependence on its angle of incidence. Such panels act as miniature light shelves. Such panels have been commercialized for purposes of daylighting, to be used as a window or a canopy such that sunlight descending from the sky is directed to the ceiling or into the room rather than to the floor. This can lead to a higher illumination of the back part of a room, in particular when combined with a white ceiling, while having a slight impact on the view to the outside compared to normal glazing.

Medicine
In particular, acrylic-type lenses are useful for cataract surgery in patients that have recurrent ocular inflammation (uveitis), as acrylic material induces less inflammation.
 * PMMA has a good degree of compatibility with human tissue, and it is used in the manufacture of rigid intraocular lenses which are implanted in the eye when the original lens has been removed in the treatment of cataracts. This compatibility was discovered by the English ophthalmologist Harold Ridley in WWII RAF pilots, whose eyes had been riddled with PMMA splinters coming from the side windows of their Supermarine Spitfire fighters – the plastic scarcely caused any rejection, compared to glass splinters coming from aircraft such as the Hawker Hurricane. Ridley had a lens manufactured by the Rayner company (Brighton & Hove, East Sussex) made from Perspex polymerised by ICI. On 29 November 1949 at St Thomas' Hospital, London, Ridley implanted the first intraocular lens at St Thomas's Hospital in London.
 * Eyeglass lenses are commonly made from PMMA.
 * Historically, hard contact lenses were frequently made of this material. Soft contact lenses are often made of a related polymer, where acrylate monomers containing one or more hydroxyl groups make them hydrophilic.
 * In orthopedic surgery, PMMA bone cement is used to affix implants and to remodel lost bone. It is supplied as a powder with liquid methyl methacrylate (MMA). Although PMMA is biologically compatible, MMA is considered to be an irritant and a possible carcinogen. PMMA has also been linked to cardiopulmonary events in the operating room due to hypotension. Bone cement acts like a grout and not so much like a glue in arthroplasty. Although sticky, it does not bond to either the bone or the implant; rather, it primarily fills the spaces between the prosthesis and the bone preventing motion. A disadvantage of this bone cement is that it heats up to 82.5 C while setting that may cause thermal necrosis of neighboring tissue. A careful balance of initiators and monomers is needed to reduce the rate of polymerization, and thus the heat generated.
 * In cosmetic surgery, tiny PMMA microspheres suspended in some biological fluid are injected as a soft-tissue filler under the skin to reduce wrinkles or scars permanently. PMMA as a soft-tissue filler was widely used in the beginning of the century to restore volume in patients with HIV-related facial wasting. PMMA is used illegally to shape muscles by some bodybuilders.
 * Plombage is an outdated treatment of tuberculosis where the pleural space around an infected lung was filled with PMMA balls, in order to compress and collapse the affected lung.
 * Emerging biotechnology and biomedical research use PMMA to create microfluidic lab-on-a-chip devices, which require 100 micrometre-wide geometries for routing liquids. These small geometries are amenable to using PMMA in a biochip fabrication process and offers moderate biocompatibility.
 * Bioprocess chromatography columns use cast acrylic tubes as an alternative to glass and stainless steel. These are pressure rated and satisfy stringent requirements of materials for biocompatibility, toxicity, and extractables.

Dentistry
Due to its aforementioned biocompatibility, poly(methyl methacrylate) is a commonly used material in modern dentistry, particularly in the fabrication of dental prosthetics, artificial teeth, and orthodontic appliances.

 * Acrylic prosthetic construction: Pre-polymerized, powdered PMMA spheres are mixed with a Methyl Methacrylate liquid monomer, Benzoyl Peroxide (initiator), and NN-Dimethyl-P-Toluidine (accelerator), and placed under heat and pressure to produce a hardened polymerized PMMA structure. Through the use of injection molding techniques, wax based designs with artificial teeth set in predetermined positions built on gypsum stone models of patients' mouths can be converted into functional prosthetics used to replace missing dentition. PMMA polymer and methyl methacrylate monomer mix is then injected into a flask containing a gypsum mold of the previously designed prosthesis, and placed under heat to initiate polymerization process. Pressure is used during the curing process to minimize polymerization shrinkage, ensuring an accurate fit of the prosthesis. Though other methods of polymerizing PMMA for prosthetic fabrication exist, such as chemical and microwave resin activation, the previously described heat-activated resin polymerization technique is the most commonly used due to its cost effectiveness and minimal polymerization shrinkage.
 * Artificial teeth: While denture teeth can be made of several different materials, PMMA is a material of choice for the manufacturing of artificial teeth used in dental prosthetics. Mechanical properties of the material allow for heightened control of aesthetics, easy surface adjustments, decreased risk of fracture when in function in the oral cavity, and minimal wear against opposing teeth. Additionally, since the bases of dental prosthetics are often constructed using PMMA, adherence of PMMA denture teeth to PMMA denture bases is unparalleled, leading to the construction of a strong and durable prosthetic.

Art and aesthetics

 * Acrylic paint essentially consists of PMMA suspended in water; however since PMMA is hydrophobic, a substance with both hydrophobic and hydrophilic groups needs to be added to facilitate the suspension.
 * Modern furniture makers, especially in the 1960s and 1970s, seeking to give their products a space age aesthetic, incorporated Lucite and other PMMA products into their designs, especially office chairs. Many other products (for example, guitars) are sometimes made with acrylic glass to make the commonly opaque objects translucent.
 * Perspex has been used as a surface to paint on, for example by Salvador Dalí.
 * Diasec is a process which uses acrylic glass as a substitute for normal glass in picture frames. This is done for its relatively low cost, light weight, shatter-resistance, aesthetics and because it can be ordered in larger sizes than standard picture framing glass.
 * As early as 1939, Los Angeles-based Dutch sculptor Jan De Swart experimented with samples of Lucite sent to him by DuPont; De Swart created tools to work the Lucite for sculpture and mixed chemicals to bring about certain effects of color and refraction.
 * From approximately the 1960s onward, sculptors and glass artists such as Jan Kubíček, Leroy Lamis, and Frederick Hart began using acrylics, especially taking advantage of the material's flexibility, light weight, cost and its capacity to refract and filter light.
 * In the 1950s and 1960s, Lucite was an extremely popular material for jewelry, with several companies specialized in creating high-quality pieces from this material. Lucite beads and ornaments are still sold by jewelry suppliers.
 * Acrylic sheets are produced in dozens of standard colors, most commonly sold using color numbers developed by Rohm & Haas in the 1950s.

Methyl methacrylate "synthetic resin" for casting (simply the bulk liquid chemical) may be used in conjunction with a polymerization catalyst such as methyl ethyl ketone peroxide (MEKP), to produce hardened transparent PMMA in any shape, from a mold. Objects like insects or coins, or even dangerous chemicals in breakable quartz ampules, may be embedded in such "cast" blocks, for display and safe handling.

Other uses

 * PMMA, in the commercial form Technovit 7200 is used vastly in the medical field. It is used for plastic histology, electron microscopy, as well as many more uses.
 * PMMA has been used to create ultra-white opaque membranes that are flexible and switch appearance to transparent when wet.
 * Acrylic is used in tanning beds as the transparent surface that separates the occupant from the tanning bulbs while tanning. The type of acrylic used in tanning beds is most often formulated from a special type of polymethyl methacrylate, a compound that allows the passage of ultraviolet rays.
 * Sheets of PMMA are commonly used in the sign industry to make flat cut out letters in thicknesses typically varying from 3 to 25 mm. These letters may be used alone to represent a company's name and/or logo, or they may be a component of illuminated channel letters. Acrylic is also used extensively throughout the sign industry as a component of wall signs where it may be a backplate, painted on the surface or the backside, a faceplate with additional raised lettering or even photographic images printed directly to it, or a spacer to separate sign components.
 * PMMA was used in Laserdisc optical media. (CDs and DVDs use both acrylic and polycarbonate for impact resistance).
 * It is used as a light guide for the backlights in TFT-LCDs.
 * Plastic optical fiber used for short-distance communication is made from PMMA, and perfluorinated PMMA, clad with fluorinated PMMA, in situations where its flexibility and cheaper installation costs outweigh its poor heat tolerance and higher attenuation versus glass fiber.
 * PMMA, in a purified form, is used as the matrix in laser dye-doped organic solid-state gain media for tunable solid state dye lasers.
 * In semiconductor research and industry, PMMA aids as a resist in the electron beam lithography process. A solution consisting of the polymer in a solvent is used to spin coat silicon and other semiconducting and semi-insulating wafers with a thin film. Patterns on this can be made by an electron beam (using an electron microscope), deep UV light (shorter wavelength than the standard photolithography process), or X-rays. Exposure to these creates chain scission or (de-cross-linking) within the PMMA, allowing for the selective removal of exposed areas by a chemical developer, making it a positive photoresist. PMMA's advantage is that it allows for extremely high resolution patterns to be made. Smooth PMMA surface can be easily nanostructured by treatment in oxygen radio-frequency plasma and nanostructured PMMA surface can be easily smoothed by vacuum ultraviolet (VUV) irradiation.
 * PMMA is used as a shield to stop beta radiation emitted from radioisotopes.
 * Small strips of PMMA are used as dosimeter devices during the Gamma Irradiation process. The optical properties of PMMA change as the gamma dose increases, and can be measured with a spectrophotometer.
 * Blacklight-reactive UV tattoos may use tattoo ink made with PMMA microcapsules and fluorescent dyes.
 * In the 1960s, luthier Dan Armstrong developed a line of electric guitars and basses whose bodies were made completely of acrylic. These instruments were marketed under the Ampeg brand. Ibanez and B.C. Rich have also made acrylic guitars.
 * Ludwig-Musser makes a line of acrylic drums called Vistalites, well known as being used by Led Zeppelin drummer John Bonham.
 * Artificial nails in the "acrylic" type often include PMMA powder.
 * Some modern briar, and occasionally meerschaum, tobacco pipes sport stems made of Lucite.
 * PMMA technology is utilized in roofing and waterproofing applications. By incorporating a polyester fleece sandwiched between two layers of catalyst-activated PMMA resin, a fully reinforced liquid membrane is created in situ.
 * PMMA is a widely used material to create deal toys and financial tombstones.
 * PMMA is used by the Sailor Pen Company of Kure, Japan, in their standard models of gold-nib fountain pens, specifically as the cap and body material.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Poly(methyl methacrylate)


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User talk:MichaelJanich

Image:Dsc04137.jpg listed for deletion
An image or media file that you uploaded or altered, Image:Dsc04137.jpg, has been listed at. Please look there to see why this is (you may have to search for the title of the image to find its entry), if you are interested in it not being deleted. Thank you. Gay Cdn (talk) (email) (Contr.) 15:29, 8 October 2006 (UTC)

Image:Dsc04394.jpg listed for deletion
An image or media file that you uploaded or altered, Image:Dsc04394.jpg, has been listed at. Please look there to see why this is (you may have to search for the title of the image to find its entry), if you are interested in it not being deleted. Thank you. Gay Cdn (talk) (email) (Contr.) 15:32, 8 October 2006 (UTC)

Moved images to commons
Hi, the who images listed above have been moved to Commons and is available as Image:India Gate.jpg and Image:Queen Victoria memorial, Kolkata.jpg so I'm deleting the "local" versions of them (we can use files from commons directly here). I would also suggest that you move the rest of your photos there too (with more descriptive filenames), that way all the Wikimedia projects can benefit from them and they don't risk deletion if they are not used in any articles because while Wikipedia is not a image repository Commons is exactly that ;-) --Sherool (talk) 16:10, 16 October 2006 (UTC)

Zudeo.com
A tag has been placed on Zudeo.com, requesting that it be speedily deleted from Wikipedia. This has been done because the article seems to be about a person, group of people, band, club, company, or web content, but it does not indicate how or why the subject is notable, that is, why an article about that subject should be included in Wikipedia. Under the criteria for speedy deletion, articles that do not assert notability may be deleted at any time. Please see the guidelines for what is generally accepted as notable, and if you can indicate why the subject of this article is notable, you may contest the tagging. To do this, add  on the top of the page and leave a note on the article's talk page explaining your position. Please do not remove the speedy deletion tag yourself, but don't hesitate to add information to the article that would confirm its subject's notability under the guidelines.

For guidelines on specific types of articles, you may want to check out our criteria for biographies, for web sites, for bands, or for companies. Feel free to leave a note on my talk page if you have any questions about this.

Please see Notability (web). -- Fan-1967 02:37, 15 January 2007 (UTC)

 * Many websites claim to be significant because of new technology, or new marketing methods, or because they are about a significant subject. None of these factors are relevant to the standards set at Notability (web). I recommend you read those standards.
 * The simple fact is that, since grokster, there have been untold thousands of startups of file-sharing websites. The measure of their notability is in their staying power, and the attention they receive from the market and the public. This site has yet to demonstrate either. Fan-1967 04:47, 15 January 2007 (UTC)

 * Again, the newness of the concept is irrelevant. What the new article has, not in the previous version, is indication of serious attention from the press. You didn't actually bother to read the Notability definition above, did you? Fan-1967 06:44, 15 January 2007 (UTC)

Mac Pro
I have left a more detailed response on the SuperDrive talk page, but here is a summarized answer for your question:
 * Mac Pro uses IDE for optical drives.
 * There are 2 SATA ports near the optical drive cage.
 * You should be able to use those ports for HDD. Freedomlinux 01:22, 8 May 2007 (UTC)

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Venue suggestion needed for a meet-up in Yuen Long

Dear:  ：

In the past meet-ups, we always had our meeting in the centre of Kowloon, either Kowloon Tong or Mong Kok. However, apart from these places, I am sure that alternative venues in other region would be suitable.

This is the time for your suggestion! According to some discussion on Chinese Wikipedia, from August of 2007, the Hong Kong Wikimedians’ meet-up would be held in all districts of Hong Kong in a circulation basis.

Here is the tentative information of the first meet-up：
 * Date： 11, August, 2007 (Saturday)
 * Time： After 5:00pm
 * Proposed region： Yuen Long

The community would request for ideas of where we should hold the meet-up , in order to have a better decision. If you have any good ideas, don’t hesitate to give your opinions, million thanks!

"Please don't hesitate to give your good suggestion to us"

Regards, Hong Kong Wikimedian Sith lord darth vader 04:26, 31 July 2007 (UTC)

JAlbum
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WikiProject Germany Invitation
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First Anniversary Celebrations of Wikimedia Hong Kong
Invitied by Sith lord darth vader (talk), 14:56, 5 July 2008 (UTC)

Speedy deletion of Foreign Correspondents' Club, Hong Kong
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Celebrations for 2nd Anniversary of Wikimedia Hong Kong

Dear:  ：

Wikimedia Hong Kong has been founded two year ago. Today, we would like to invite you to a great event for our second anniversary celebrations, that is co-host by us - Digital Content Jam 1.0, which is belongs to The 3C Digital Creativity Dialogue Series -- Creativity, Content, Community.

This is the information of the event：

 * Date: 31, July, 2009 (Friday)
 * Time: From 7:00pm to 9:30pm
 * Venue: eTech Centre Meeting Room M2 &3, 4/F Opulent Building, 402-406 Hennessy Road, Wan Chai（Google map）
 * '''Language: Cantonese
 * Free snacks and drinks will be served!

'''Please register via the link below to tell us if you would like to join the event. Registration Form'''

Regards, Hong Kong Wikimedian Tango Chan×Chat with me 11:03, 18 July 2009 (UTC)

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ArbCom elections are now open!
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text:
Equilateral triangle

In geometry, an equilateral triangle is a triangle in which all three sides have the same length. In the familiar Euclidean geometry, an equilateral triangle is also equiangular; that is, all three internal angles are also congruent to each other and are each 60°. It is also a regular polygon, so it is also referred to as a regular triangle.

Principal properties

Denoting the common length of the sides of the equilateral triangle as $$a$$, we can determine using the Pythagorean theorem that:
 * The area is $$A=\frac{\sqrt{3}}{4} a^2,$$
 * The perimeter is $$p=3a\,\!$$
 * The radius of the circumscribed circle is $$R = \frac{a}{\sqrt{3}}$$
 * The radius of the inscribed circle is $$r=\frac{\sqrt{3}}{6} a$$ or $$ r=\frac{R}{2}$$
 * The geometric center of the triangle is the center of the circumscribed and inscribed circles
 * The altitude (height) from any side is $$h=\frac{\sqrt{3}}{2} a$$

Denoting the radius of the circumscribed circle as R, we can determine using trigonometry that: $$ Many of these quantities have simple relationships to the altitude ("h") of each vertex from the opposite side:
 * The area of the triangle is $$A=\frac{3\sqrt{3}}{4}R^2
 * The area is $$A=\frac{h^2}{\sqrt{3}}$$
 * The height of the center from each side, or apothem, is $$\frac{h}{3} $$
 * The radius of the circle circumscribing the three vertices is $$R=\frac{2h}{3} $$
 * The radius of the inscribed circle is $$r=\frac{h}{3}$$

In an equilateral triangle, the altitudes, the angle bisectors, the perpendicular bisectors, and the medians to each side coincide.

Characterizations
A triangle $$ABC$$ that has the sides $$a$$, $$b$$, $$c$$, semiperimeter $$s$$, area $$T$$, exradii $$r_{a}$$, $$r_{b}$$, $$r_{c}$$ (tangent to $$a$$, $$b$$, $$c$$ respectively), and where $$R$$ and $$r$$ are the radii of the circumcircle and incircle respectively, is equilateral if and only if any one of the statements in the following nine categories is true. Thus these are properties that are unique to equilateral triangles, and knowing that any one of them is true directly implies that we have an equilateral triangle.

Sides

 * $$ a=b=c$$
 * $$ \frac{1}{a}+\frac{1}{b}+\frac{1}{c}=\frac{\sqrt{25Rr-2r^2}}{4Rr}$$

Semiperimeter

 * $$ s = 2R + \left(3\sqrt{3} - 4\right)r$$ (Blundon)
 * $$ s^2=3r^2+12Rr$$
 * $$ s^2=3\sqrt{3}T$$
 * $$ s=3\sqrt{3}r$$
 * $$ s=\frac{3\sqrt{3}}{2}R$$

Angles

 * $$ A=B=C=60^\circ$$
 * $$ \cos{A}+\cos{B}+\cos{C}=\frac{3}{2}$$
 * $$ \sin{\frac{A}{2}}\sin{\frac{B}{2}}\sin{\frac{C}{2}}=\frac{1}{8}$$

Area

 * $$ T=\frac{a^2+b^2+c^2}{4\sqrt{3}}\quad$$ (Weitzenböck)
 * $$ T=\frac{\sqrt{3}}{4}(abc)^\frac{2}{3}$$

Circumradius, inradius, and exradii

 * $$ R=2r$$ (Chapple-Euler)
 * $$ 9R^2=a^2+b^2+c^2$$
 * $$ r=\frac{r_a+r_b+r_c}{9}$$
 * $$ r_a=r_b=r_c$$

Equal cevians
Three kinds of cevians coincide, and are equal, for (and only for) equilateral triangles:
 * The three altitudes have equal lengths.
 * The three medians have equal lengths.
 * The three angle bisectors have equal lengths.

Coincident triangle centers
Every triangle center of an equilateral triangle coincides with its centroid, which implies that the equilateral triangle is the only triangle with no Euler line connecting some of the centers. For some pairs of triangle centers, the fact that they coincide is enough to ensure that the triangle is equilateral. In particular:

 * A triangle is equilateral if any two of the circumcenter, incenter, centroid, or orthocenter coincide.
 * It is also equilateral if its circumcenter coincides with the Nagel point, or if its incenter coincides with its nine-point center.

Six triangles formed by partitioning by the medians
For any triangle, the three medians partition the triangle into six smaller triangles.
 * A triangle is equilateral if and only if any three of the smaller triangles have either the same perimeter or the same inradius.
 * A triangle is equilateral if and only if the circumcenters of any three of the smaller triangles have the same distance from the centroid.

Points in the plane

 * A triangle is equilateral if and only if, for every point $$P$$ in the plane, with distances $$p$$, $$q$$, and $$r$$ to the triangle's sides and distances $$x$$, $$y$$, and $$z$$ to its vertices, $$4\left(p^2 + q^2 + r^2\right) \geq x^2 + y^2 + z^2.$$

Notable theorems
Morley's trisector theorem states that, in any triangle, the three points of intersection of the adjacent angle trisectors form an equilateral triangle.

Napoleon's theorem states that, if equilateral triangles are constructed on the sides of any triangle, either all outward, or all inward, the centers of those equilateral triangles themselves form an equilateral triangle.

A version of the isoperimetric inequality for triangles states that the triangle of greatest area among all those with a given perimeter is equilateral.

Viviani's theorem states that, for any interior point $$P$$ in an equilateral triangle with distances $$d$$, $$e$$, and $$f$$ from the sides and altitude $$h$$, $$d+e+f = h,$$ independent of the location of $$P$$.

Pompeiu's theorem states that, if $$P$$ is an arbitrary point in the plane of an equilateral triangle $$ABC$$ but not on its circumcircle, then there exists a triangle with sides of lengths $$PA$$, $$PB$$, and $$PC$$. That is, $$PA$$, $$PB$$, and $$PC$$ satisfy the triangle inequality that the sum of any two of them is greater than the third. If $$P$$ is on the circumcircle then the sum of the two smaller ones equals the longest and the triangle has degenerated into a line, this case is known as Van Schooten's theorem.

Geometric construction

An equilateral triangle is easily constructed using a straightedge and compass, because 3 is a Fermat prime. Draw a straight line, and place the point of the compass on one end of the line, and swing an arc from that point to the other point of the line segment. Repeat with the other side of the line. Finally, connect the point where the two arcs intersect with each end of the line segment.

An alternative method is to draw a circle with radius $$r$$, place the point of the compass on the circle and draw another circle with the same radius. The two circles will intersect in two points. An equilateral triangle can be constructed by taking the two centers of the circles and either of the points of intersection.

In both methods a by-product is the formation of vesica piscis.

The proof that the resulting figure is an equilateral triangle is the first proposition in Book I of Euclid's Elements.

Derivation of area formula
The area formula $$A = \frac{\sqrt{3}}{4}a^2$$ in terms of side length $$a$$ can be derived directly using the Pythagorean theorem or using trigonometry.

Using the Pythagorean theorem
The area of a triangle is half of one side $$a$$ times the height $$h$$ from that side: $$A = \frac{1}{2} ah.$$

The legs of either right triangle formed by an altitude of the equilateral triangle are half of the base $$a$$, and the hypotenuse is the side $$a$$ of the equilateral triangle. The height of an equilateral triangle can be found using the Pythagorean theorem $$\left(\frac{a}{2}\right)^2 + h^2 = a^2$$ so that $$h = \frac{\sqrt{3}}{2}a.$$

Substituting $$h$$ into the area formula $$\frac{1}{2}ah$$ gives the area formula for the equilateral triangle: $$A = \frac{\sqrt{3}}{4}a^2.$$

Using trigonometry
Using trigonometry, the area of a triangle with any two sides $$a$$ and $$b$$, and an angle $$C$$ between them is $$A = \frac{1}{2} ab \sin C.$$

Each angle of an equilateral triangle is 60°, so $$A = \frac{1}{2} ab \sin 60^\circ.$$

The sine of 60° is $$\tfrac{\sqrt{3}}{2}$$. Thus $$A = \frac{1}{2} ab \times \frac{\sqrt{3}}{2} = \frac{\sqrt{3}}{4}ab = \frac{\sqrt{3}}{4}a^2$$ since all sides of an equilateral triangle are equal.

Other properties
An equilateral triangle is the most symmetrical triangle, having 3 lines of reflection and rotational symmetry of order 3 about its center, whose symmetry group is the dihedral group of order 6, $$\mathrm D_{3}$$. The integer-sided equilateral triangle is the only triangle with integer sides, and three rational angles as measured in degrees. It is the only acute triangle that is similar to its orthic triangle (with vertices at the feet of the altitudes), and the only triangle whose Steiner inellipse is a circle (specifically, the incircle). The triangle of largest area of all those inscribed in a given circle is equilateral, and the triangle of smallest area of all those circumscribed around a given circle is also equilateral. It is the only regular polygon aside from the square that can be inscribed inside any other regular polygon.

By Euler's inequality, the equilateral triangle has the smallest ratio of the circumradius $$R$$ to the inradius $$r$$ of any triangle, with $$\frac {R}{r} = 2.$$

Given a point $$P$$ in the interior of an equilateral triangle, the ratio of the sum of its distances from the vertices to the sum of its distances from the sides is greater than or equal to 2, equality holding when $$P$$ is the centroid. In no other triangle is there a point for which this ratio is as small as 2. This is the Erdős–Mordell inequality; a stronger variant of it is Barrow's inequality, which replaces the perpendicular distances to the sides with the distances from $$P$$ to the points where the angle bisectors of $$\angle APB$$, $$\angle BPC$$, and $$\angle CPA$$ cross the sides ($$A$$, $$B$$, and $$C$$ being the vertices). There are numerous other triangle inequalities that hold with equality if and only if the triangle is equilateral.

For any point $$P$$ in the plane, with distances $$p$$, $$q$$, and $$t$$ from the vertices $$A$$, $$B$$, and $$C$$ respectively, $$ 3 \left(p^4 + q^4 + t^4 + a^4\right) = \left(p^2 + q^2 + t^2 + a^2\right)^2.$$

For any point $$P$$ in the plane, with distances $$p$$, $$q$$, and $$t$$ from the vertices, $$ p^2+q^2+t^2 = 3\left(R^2 + L^2\right),$$ $$ p^4+q^4+t^4 = 3\left[\left(R^2 + L^2\right)^2 + 2 R^2 L^2\right],$$ where $$R$$ is the circumscribed radius and $$L$$ is the distance between point $$P$$ and the centroid of the equilateral triangle.

For any point $$P$$ on the inscribed circle of an equilateral triangle, with distances $$p$$, $$q$$, and $$t$$ from the vertices, $$ 4 \left(p^2 + q^2 + t^2\right) = 5a^2,$$ $$ 16 \left(p^4 + q^4 + t^4\right) = 11a^4.$$

For any point $$P$$ on the minor arc $$BC$$ of the circumcircle, with distances $$p$$, $$q$$, and $$t$$ from $$A$$, $$B$$, and $$C$$, respectively $$ p = q + t,$$ $$ q^2 + qt + t^2=a^2 .$$

Moreover, if point $$D$$ on side $$BC$$ divides $$PA$$ into segments $$PD$$ and $$DA$$ with $$DA$$ having length $$z$$ and $$PD$$ having length $$y$$, then $$z = \frac{t^2 + tq + q^2}{t + q},$$ which also equals $\tfrac{t^3 - q^3}{t^2 - q^2}$ if $$t \neq q$$ and $$\frac{1}{q}+\frac{1}{t}=\frac{1}{y} ,$$ which is the optic equation.

For an equilateral triangle:

 * The ratio of its area to the area of the incircle, $$\frac{\pi}{3\sqrt{3}}$$, is the largest of any triangle.

 * The ratio of its area to the square of its perimeter, $$\frac{1}{12\sqrt{3}},$$ is larger than that of any non-equilateral triangle.

$$\frac{7}{9} \leq \frac{A_1}{A_2} \leq \frac{9}{7}.$$
 * If a segment splits an equilateral triangle into two regions with equal perimeters and with areas $$A_{1}$$ and $$A_{2}$$, then

If a triangle is placed in the complex plane with complex vertices $$z_{1}$$, $$z_{2}$$, and $$z_{3}$$, then for either non-real cube root $$\omega$$ of 1 the triangle is equilateral if and only if $$z_1 + \omega z_2 + \omega^2 z_3 = 0.$$

Notably, the equilateral triangle tiles two dimensional space with six triangles meeting at a vertex, whose dual tessellation is the hexagonal tiling. 3.122, 3.4.6.4, (3.6)2, 32.4.3.4, and 34.6 are all semi-regular tessellations constructed with equilateral triangles.

In three dimensions, equilateral triangles form faces of regular and uniform polyhedra. Three of the five Platonic solids are composed of equilateral triangles: the tetrahedron, octahedron and icosahedron. In particular, the tetrahedron, which has four equilateral triangles for faces, can be considered the three-dimensional analogue of the triangle. All Platonic solids can inscribe tetrahedra, as well as be inscribed inside tetrahedra. Equilateral triangles also form uniform antiprisms as well as uniform star antiprisms in three-dimensional space. For antiprisms, two (non-mirrored) parallel copies of regular polygons are connected by alternating bands of $$2n$$ equilateral triangles. Specifically for star antiprisms, there are prograde and retrograde (crossed) solutions that join mirrored and non-mirrored parallel star polygons. The Platonic octahedron is also a triangular antiprism, which is the first true member of the infinite family of antiprisms (the tetrahedron, as a digonal antiprism, is sometimes considered the first).

As a generalization, the equilateral triangle belongs to the infinite family of $$n$$-simplexes, with $$n = 2$$.

In culture and society
Equilateral triangles have frequently appeared in man made constructions:
 * The shape occurs in modern architecture such as the cross-section of the Gateway Arch.
 * Its applications in flags and heraldry includes the flag of Nicaragua and the flag of the Philippines.
 * It is a shape of a variety of road signs, including the yield sign.

title: Equilateral triangle


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Extropianism

Extropianism, also referred to as the philosophy of extropy, is an "evolving framework of values and standards for continuously improving the human condition". Extropians believe that advances in science and technology will some day let people live indefinitely. An extropian may wish to contribute to this goal, e.g. by doing research and development or by volunteering to test new technology.

Originated by a set of principles developed by the philosopher Max More in The Principles of Extropy, extropian thinking places strong emphasis on rational thinking and on practical optimism. According to More, these principles "do not specify particular beliefs, technologies, or policies". Extropians share an optimistic view of the future, expecting considerable advances in computational power, life extension, nanotechnology and the like. Many extropians foresee the eventual realization of indefinite lifespans or immortality, and the recovery, thanks to future advances in biomedical technology or mind uploading, of those whose bodies/brains have been preserved by means of cryonics.

Extropy
The term extropy, as an antonym to "entropy" was used in a 1967 academic volume discussing cryogenics and in a 1978 academic volume of cybernetics. Diane Duane in 1983 was the first to use the term "extropy" to signify a potential transhuman destiny for humanity. Also published in 1983 was J. Neil Schulman's Prometheus Award winning novel, The Rainbow Cadenza which used the term "extropic" as a type of scale in visual music. 'Extropy' as coined by Tom Bell (T.O. Morrow) and defined by Max More in 1988, is "the extent of a living or organizational system's intelligence, functional order, vitality, energy, life, experience, and capacity and drive for improvement and growth." Extropy is not a rigorously defined technical term in philosophy or science; in a metaphorical sense, it simply expresses the opposite of entropy.

Extropy Institute
In 1986, More joined Alcor, a cryonics company, and helped establish (along with Michael Price, Garret Smyth and Luigi Warren) the first European cryonics organization, Mizar Limited (later Alcor UK). In 1987, More moved to Los Angeles from Oxford University in England to work on his Ph.D. in philosophy at the University of Southern California.

In 1988, Extropy: The Journal of Transhumanist Thought was first published. (For the first few issues, it was "Extropy: Vaccine for Future Shock".) This brought together thinkers with interests in artificial intelligence, nanotechnology, genetic engineering, life extension, mind uploading, idea futures, robotics, space exploration, memetics, and the politics and economics of transhumanism. Alternative media organizations soon began reviewing the magazine, and it attracted interest from like-minded thinkers. Later, More and Bell co-founded the Extropy Institute, a non-profit 501(c)(3) educational organization. "ExI" was formed as a transhumanist networking and information center to use current scientific understanding along with critical and creative thinking to define a small set of principles or values that could help make sense of new capabilities opening up to humanity.

In 2006, the board of directors of the Extropy Institute made a decision to close the organisation, stating that its mission was "essentially completed."

Extropism
Extropism is a derivation of the transhumanist philosophy of extropianism. It follows the same tradition – hence the similarity in naming – but has been revised to better suit the perceived paradigms of the 21st century. As introduced in The Extropist Manifesto, it promotes an optimistic futuristic philosophy that can be summed up in the following five phrases, which spell out the word "EXTROPISM":

 * Endless eXtension
 * Transcending Restriction
 * Overcoming Property
 * Intelligence
 * Smart Machines

Extropists desire to prolong their life span to a near-immortal state and exist in a world where artificial intelligence and robotics have made work irrelevant. As in utilitarianism, the purpose of one's life should be to increase the overall happiness of all creatures on Earth through cooperation.

The Extropist Manifesto was written by web entrepreneur Breki Tomasson and writer Hank Pellissier – both of whom have had a long transhuman interest – in January, 2010. It details the ways in which extropism has evolved away from extropianism, while continuing to build upon its original tenets. For example, it moves away from the original Extropian Principles by placing a significant focus on the need to abolish and/or restrict the current use of surveillance, copyright and patent laws.

title: Extropianism