Neutronium is a term used in science fiction and popular literature to refer to an extremely dense phase of matter composed primarily of neutrons. The word had been coined by Andreas von Antropoff in 1926 (scil., before the discovery of the neutron itself) for the 'element of atomic number zero' that he placed at the head of the periodic table. The meaning of the term changed over time, and from the last half of the 20th century onwards it was used to refer to extremely dense phases of matter resembling the neutron-degenerate matter postulated to exist in the cores of neutron stars. Science fiction is a form of speculative fiction principally dealing with the impact of imagined science and technology, or both, upon society and persons as individuals. ... In mathematics, the term dense has at least three different meanings. ... In the physical sciences, a phase is a set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties (i. ... Properties In physics, the neutron is a subatomic particle with no net electric charge and a mass of 939. ... 1926 (MCMXXVI) was a common year starting on Friday (link will take you to calendar). ... Properties In physics, the neutron is a subatomic particle with no net electric charge and a mass of 939. ... (19th century - 20th century - 21st century - more centuries) Decades: 1900s 1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s As a means of recording the passage of time, the 20th century was that century which lasted from 1901–2000 in the sense of the Gregorian calendar (1900–1999 in the... Degenerate matter is matter which has sufficiently high density that the dominant contribution to its pressure arises from the Pauli exclusion principle. ... Neutron stars are one of the few possible endpoints of stellar evolution. ...

Neutronium and neutron stars

The term neutronium is used in popular literature to refer to the material present in the cores of neutron stars (stars which are too massive to be supported by electron degeneracy pressure and which collapse into a denser phase of matter). This term is very rarely used in scientific literature, for two reasons: Neutron stars are one of the few possible endpoints of stellar evolution. ... Degenerate matter is matter which has sufficiently high density that the dominant contribution to its pressure arises from the Pauli exclusion principle. ...

• There is no universally agreed-upon definition for the term "neutronium".
• There is very considerable uncertainty over the composition of the material in the cores of neutron stars (it could be neutron-degenerate matter, strange matter, quark matter, or a variant or combination of the above).

A more detailed discussion of the structure of neutron stars is presented in the neutron star article. When neutron star core material is presumed to consist mostly of free neutrons, it is typically referred to as neutron-degenerate matter in scientific literature. Neutron stars are one of the few possible endpoints of stellar evolution. ... Degenerate matter is matter which has sufficiently high density that the dominant contribution to its pressure arises from the Pauli exclusion principle. ... Strange matter is an ultra-dense phase of matter that is theorized to form inside particularly massive neutron stars. ... Quark Matter refers to any of a number of phases of matter built out of quarks and gluons. ... Neutron stars are one of the few possible endpoints of stellar evolution. ... Neutron stars are one of the few possible endpoints of stellar evolution. ... Neutron stars are one of the few possible endpoints of stellar evolution. ... Degenerate matter is matter which has sufficiently high density that the dominant contribution to its pressure arises from the Pauli exclusion principle. ...

Neutronium and the periodic table

The term neutronium was coined in 1926 by Professor Andreas von Antropoff for a form of matter made up of neutrons with no protons, which he placed as the element of atomic number zero at the head of his new version of the periodic table. It was subsequently placed as a noble gas in the middle of several spiral representations of the periodic system for classifying the chemical elements. It is at the centre of the Chemical Galaxy (2005). Properties In physics, the neutron is a subatomic particle with no net electric charge and a mass of 940 MeV/c² (1. ... For alternative meanings see proton (disambiguation). ... Look up element in Wiktionary, the free dictionary. ... The atomic number (Z) is a term used in chemistry and physics to represent the number of protons found in the nucleus of an atom. ... The periodic table of the chemical elements, also called the Mendeleev periodic table, is a tabular display of chemical elements, first created in 1869 by Russian chemist Dmitri Mendeleev. ... The noble gases are the chemical elements in group 18 (old-style Group 0) of the periodic table. ... A chemical element, often called simply element, is a substance that cannot be divided or changed into different substances by ordinary chemical methods. ... The Chemical Galaxy is a new periodic table designed by Philip Stewart in November 2004 based on the cyclical nature of characteristics of the chemical elements (which depend principally on the valence electrons). ...

Although the term is still not widely used in the scientific literature for a condensed form of matter, there are indications that, besides the free neutron, there may exist two isotopes without protons. Further information can be found in the following articles: A free neutron is a neutron that exists outside of an atomic nucleus. ... Isotopes are atoms of a chemical element whose nuclei have the same atomic number, Z, but different atomic weights, A. The word isotope, meaning at the same place, comes from the fact that isotopes are located at the same place on the periodic table. ...

• Free neutron: Isolated neutrons undergo beta decay with a half-life of approximately 10 minutes, becoming protons (the nucleus of hydrogen).
• Dineutron: The dineutron, containing two bound neutrons, is proposed as an extremely short-lived state produced by nuclear reactions involving tritium.
• Tetraneutron: A tetraneutron is a hypothetical particle consisting of four bound neutrons. It is expected to have a half-life considerably longer than that of the dineutron.

A trineutron state consisting of three bound neutrons has not been detected, and is not expected to be stable even for a short time. Calculations indicate that the hypothetical pentaneutron state, consisting of a cluster of five neutrons, would not be bound. [1] A free neutron is a neutron that exists outside of an atomic nucleus. ... Properties In physics, the neutron is a subatomic particle with no net electric charge and a mass of 939. ... In nuclear physics, beta decay (sometimes called neutron decay) is a type of radioactive decay in which a beta particle (an electron or a positron) is emitted. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... This article contains information that has not been verified. ... Properties In physics, the proton (Greek proton = first) is a subatomic particle with an electric charge of one positive fundamental unit (1. ... A stylized representation of a lithium atom. ... General Name, Symbol, Number hydrogen, H, 1 Chemical series nonmetals Group, Period, Block 1, 1, s Appearance colorless Atomic mass 1. ... A dineutron is a particle consisting of two neutrons that is considered to have a transitory existence in nuclear reactions produced by helions that result in the formation of a proton and a nucleus having the same atomic number as the target nucleus but a mass number two units greater. ... A dineutron is a particle consisting of two neutrons that is considered to have a transitory existence in nuclear reactions produced by helions that result in the formation of a proton and a nucleus having the same atomic number as the target nucleus but a mass number two units greater. ... Tritium (symbol T or 3H) is a radioactive isotope of hydrogen. ... A tetraneutron is a hypothesised stable cluster of four neutrons. ... A tetraneutron is a hypothesised stable cluster of four neutrons. ... A dineutron is a particle consisting of two neutrons that is considered to have a transitory existence in nuclear reactions produced by helions that result in the formation of a proton and a nucleus having the same atomic number as the target nucleus but a mass number two units greater. ...

If one were to somehow allow the definition of an element without protons, that hypothetical 'element zero' could be systematically named nilium. However the systematic symbol (N), even though similar to the symbol for a neutron (n), conflicts with nitrogen. Most prefer the trivial name neutronium. If the systematic names require three letters, then this would be "Nnn" (nilnilnilium). One alternative is to state that nil (n) is not written in leading positions and is never capitalized. That makes the symbol for nilium (n) exactly that of the neutron (n). Properties In physics, the neutron is a subatomic particle with no net electric charge and a mass of 939. ... This article does not cite its references or sources. ...

Neutronium in fiction

The term neutronium has been popular in science fiction since at least the middle of the 20th century. It typically refers to an extremely dense, incredibly strong form of matter. While presumably inspired by the concept of neutron-degenerate matter in the cores of neutron stars, the material used in fiction bears at most only a superficial resemblance (usually depicted as an extremely strong solid under Earthlike conditions, while all proposed forms of neutron star core material are fluids and are extremely unstable at pressures lower than that found in stellar cores). Science fiction is a form of speculative fiction principally dealing with the impact of imagined science and technology, or both, upon society and persons as individuals. ... (19th century - 20th century - 21st century - more centuries) Decades: 1900s 1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s As a means of recording the passage of time, the 20th century was that century which lasted from 1901–2000 in the sense of the Gregorian calendar (1900–1999 in the... Degenerate matter is matter which has sufficiently high density that the dominant contribution to its pressure arises from the Pauli exclusion principle. ... Neutron stars are one of the few possible endpoints of stellar evolution. ... Earth, also known as Terra, and Tellus mostly in the 19th century, is the third-closest planet to the Sun. ... Neutron stars are one of the few possible endpoints of stellar evolution. ... A subset of the phases of matter, fluids include liquids, gases, plasmas and, to some extent, plastic solids. ... Pressure (symbol: p) is the force per unit area acting on a surface in a direction perpendicular to that surface. ... The Pleiades star cluster A star is a massive body of plasma in outer space that is currently producing or has produced energy through nuclear fusion. ...

Noteworthy appearances of neutronium in fiction include the following:

• In Star Trek, neutronium is an extermely hard and durable substance, often used as armor, which conventional weapons cannot penetrate or even dent. The alien "planetkiller" seen in the Star Trek: The Original Series episode "The Doomsday Machine", had a hull comprised of indestructible neutronium.
• In Doctor Who, neutronium is a substance which can shield spaces from time-shear when used as shielding in time-vessels.
• In Peter F. Hamilton's The Neutronium Alchemist, neutronium is a component of a superweapon.
• In Stargate SG-1, neutronium is a substance which is the basis of the technology of the advanced Asgard race, as well as a primary component of human-form Replicators.
• In the Known Space fictional universe of Larry Niven, neutronium is actual neutron star core material. Niven does not make assumptions about its strength, but imagines that small blobs of it would remain stable (and inevitably spherical) under their own gravity.
• In Greg Bear's The Planet-Killers (or The Law) duology, neutronium and anti-neutronium are used to destroy planet Earth.
• In the computer games Master of Orion and Sid Meier's Alpha Centauri, neutronium is a possible armor type that can be researched.
• In the book Die Herren der Schwarzen Festung by the german writer Wolfgang Hohlbein, neutronium is capable of holding two black holes away from each other.

Note that if neutronium were to be released of the immense pressures of gravity within the neutron star, it would instantly explode with immense force. This makes the aforementioned uses impossible without altering the element in some way, but does leave open the obvious possiblity of a superbomb. However, even if it would able to be harvested released of the immense pressures of gravity within the neutron star, its mass would most likely prevent this. Star Trek collectively refers to a science-fiction franchise spanning six unique television series, 726 episodes and ten motion pictures in addition to hundreds of novels, video games, and other works of fiction all set within the same fictional universe created by Gene Roddenberry in the mid-1960s. ... The starship Enterprise as it appeared on Star Trek Star Trek is a culturally significant science fiction television series created by Gene Roddenberry in the 1960s. ... The Doomsday Machine is an episode of Star Trek: The Original Series. ... The Doctor Who 2005 television series logo. ... Peter F. Hamilton Peter F. Hamilton Peter F. Hamilton (born 1960, Rutland, England), is a British science fiction author. ... The Neutronium Alchemist is the second book in The Nights Dawn Trilogy by Peter F. Hamilton, the first being The Reality Dysfunction and the third being The Naked God. ... A superweapon is an extremely powerful weapon by the standards of its time and its scale. ... ..... Stargate SG-1 (alternately spelled Stargåte, and popularly abbreviated as SG-1) is a television series based upon the 1994 science fiction film Stargate. ... Known Space is the fictional setting of many of Larry Nivens science fiction stories. ... A fictional universe is a cohesive imaginary world that serves as the setting or backdrop for one or (more commonly) multiple works of fiction. ... Larry Niven Laurence van Cott Niven (born April 30, 1938) is a US science fiction author. ... Neutron stars are one of the few possible endpoints of stellar evolution. ... Gregory Dale Bear (born August 20, 1951) is a science fiction author. ... Duology also known as dilogy is a set of three works of art, usually literature or film, that develop a single theme over two works. ... Neutronium is a term used in science fiction and popular literature to refer to an extremely dense phase of matter composed primarily of neutrons. ... A computer game is a game composed of a computer-controlled virtual universe that players interact with in order to achieve a defined goal or set of goals. ... Master of Orion (MOO or MoO) is an intergalactic turn-based computer strategy game that was released in 1993. ... Sid Meiers Alpha Centauri (sometimes abbreviated to SMAC) is a turn-based strategy 4X computer game created by Brian Reynolds and Sid Meier under the auspices of Firaxis Games in 1999. ... Alternative meanings: vehicle armour, Armor (novel) A hoplite wearing a helmet, a breastplate and greaves (and nothing else). ... Wolfgang Hohlbein (* August 11, 1953) German writer who was born in Weimar. ...

See also

• Neutron star
• Degenerate matter
• Compact star
• Antineutron

Neutron stars are one of the few possible endpoints of stellar evolution. ... Degenerate matter is matter which has sufficiently high density that the dominant contribution to its pressure arises from the Pauli exclusion principle. ... In astronomy, a compact star (sometimes called a compact object) is a star that is a white dwarf, a neutron star, a strange star, or a black hole. ... The antineutron is the antiparticle of the neutron. ...

References

• Norman K. Glendenning, R. Kippenhahn, I. Appenzeller, G. Borner, M. Harwit (2000). Compact Stars, 2nd ed.