Q star

A Q-Star, also known as a grey hole, is a hypothetical type of a compact, heavy neutron star with an exotic state of matter. The Q stands for a conserved particle number. A Q-Star may be mistaken for a stellar black hole.

Types of Q-stars

  • SUSY Q-ball[1]
  • B-ball, stable Q-balls with a large baryon number B. They may exist in neutron stars that have absorbed Q-ball(s).[1]

See also


  1. ^ a b Properties and signatures of supersymmetric Q-balls, Alexander Kusenko, 2006

External links


In abstract algebra, the biquaternions are the numbers w + x i + y j + z k, where w, x, y, and z are complex numbers, or variants thereof, and the elements of {1, i, j, k} multiply as in the quaternion group and commute with their coefficients. There are three types of biquaternions corresponding to complex numbers and the variations thereof:

Biquaternions when the coefficients are complex numbers.

Split-biquaternions when the coefficients are split-complex numbers.

Dual quaternions when the coefficients are dual numbers.This article is about the ordinary biquaternions named by William Rowan Hamilton in 1844 (see Proceedings of the Royal Irish Academy 1844 & 1850 page 388). Some of the more prominent proponents of these biquaternions include Alexander Macfarlane, Arthur W. Conway, Ludwik Silberstein, and Cornelius Lanczos. As developed below, the unit quasi-sphere of the biquaternions provides a representation of the Lorentz group, which is the foundation of special relativity.

The algebra of biquaternions can be considered as a tensor product ℂ ⊗ ℍ (taken over the reals) where ℂ is the field of complex numbers and ℍ is the division algebra of (real) quaternions. In other words, the biquaternions are just the complexification of the quaternions. Viewed as a complex algebra, the biquaternions are isomorphic to the algebra of 2 × 2 complex matrices M2(ℂ). They are also isomorphic to several Clifford algebras including ℍ(ℂ) = Cℓ03(ℂ) = Cℓ2(ℂ) = Cℓ1,2(ℝ), the Pauli algebra Cℓ3,0(ℝ), and the even part Cℓ01,3(ℝ) = Cℓ03,1(ℝ) of the spacetime algebra.

Black hole

A black hole is a region of spacetime exhibiting gravitational acceleration so strong that nothing—no particles or even electromagnetic radiation such as light—can escape from it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole. The boundary of the region from which no escape is possible is called the event horizon. Although the event horizon has an enormous effect on the fate and circumstances of an object crossing it, no locally detectable features appear to be observed. In many ways, a black hole acts like an ideal black body, as it reflects no light. Moreover, quantum field theory in curved spacetime predicts that event horizons emit Hawking radiation, with the same spectrum as a black body of a temperature inversely proportional to its mass. This temperature is on the order of billionths of a kelvin for black holes of stellar mass, making it essentially impossible to observe.

Objects whose gravitational fields are too strong for light to escape were first considered in the 18th century by John Michell and Pierre-Simon Laplace. The first modern solution of general relativity that would characterize a black hole was found by Karl Schwarzschild in 1916, although its interpretation as a region of space from which nothing can escape was first published by David Finkelstein in 1958. Black holes were long considered a mathematical curiosity; it was during the 1960s that theoretical work showed they were a generic prediction of general relativity. The discovery of neutron stars by Jocelyn Bell Burnell in 1967 sparked interest in gravitationally collapsed compact objects as a possible astrophysical reality.

Black holes of stellar mass are expected to form when very massive stars collapse at the end of their life cycle. After a black hole has formed, it can continue to grow by absorbing mass from its surroundings. By absorbing other stars and merging with other black holes, supermassive black holes of millions of solar masses (M☉) may form. There is general consensus that supermassive black holes exist in the centers of most galaxies.

The presence of a black hole can be inferred through its interaction with other matter and with electromagnetic radiation such as visible light. Matter that falls onto a black hole can form an external accretion disk heated by friction, forming some of the brightest objects in the universe. If there are other stars orbiting a black hole, their orbits can be used to determine the black hole's mass and location. Such observations can be used to exclude possible alternatives such as neutron stars. In this way, astronomers have identified numerous stellar black hole candidates in binary systems, and established that the radio source known as Sagittarius A*, at the core of the Milky Way galaxy, contains a supermassive black hole of about 4.3 million solar masses.

On 11 February 2016, the LIGO collaboration announced the first direct detection of gravitational waves, which also represented the first observation of a black hole merger. As of December 2018, eleven gravitational wave events have been observed that originated from ten merging black holes (along with one binary neutron star merger). On 10 April 2019, the first ever direct image of a black hole and its vicinity was published, following observations made by the Event Horizon Telescope in 2017 of the supermassive black hole in Messier 87's galactic centre.

Déjà Q

"Deja Q" is the 13th episode of the third season of the American science fiction television series Star Trek: The Next Generation, and the 61st episode of the series overall.

As the crew of the starship Enterprise struggle to prevent a moon from falling out of orbit, their situation is further complicated by a visit from a powerful nemesis named "Q" (John de Lancie), who informs them that he has been stripped of all his powers and must live out a mortal life.

Energy being

An energy being or astral being is a theoretical life form that is composed of energy rather than matter. They appear in myths/legends, paranormal/UFO accounts, and in various works of speculative fiction.

Energy beings are typically rendered as a translucent glowing fluid or as a collection of flames or electrical sparks or bolts; somewhat in common with the representations of ghosts.

Energy beings have a variety of capacities. The Taelons (from Earth: Final Conflict) are barely more powerful than mortals, while others such as Star Trek's Q, Stargate SG-1's Ascended Ancients/Ori, Ben 10: Alien Force's Anodites, or the Meekrob from Invader Zim possess god-like powers.

Exotic star

An exotic star is a hypothetical compact star composed of something other than electrons, protons, neutrons, or muons, and balanced against gravitational collapse by degeneracy pressure or other quantum properties. Exotic stars include quark stars (composed of quarks) and perhaps strange stars (composed of strange quark matter, a condensate of up, down and strange quarks), as well as speculative preon stars (composed of preons, which are hypothetical particles and "building blocks" of quarks, should quarks be decomposable into component sub-particles). Of the various types of exotic star proposed, the most well evidenced and understood is the quark star.

Exotic stars are largely theoretical – partly because it is difficult to test in detail how such forms of matter may behave, and partly because prior to the fledgling technology of gravitational-wave astronomy, there was no satisfactory means of detecting cosmic objects that do not radiate electromagnetically or through known particles. So it is not yet possible to verify novel cosmic objects of this nature by distinguishing them from known objects. Candidates for such objects are occasionally identified based on indirect evidence gained from observable properties.

Hide and Q

"Hide and Q" is the tenth episode of the first season of the American science fiction television series Star Trek: The Next Generation, and originally aired on November 23, 1987, in broadcast syndication. The story was originally written by Maurice Hurley but went under numerous re-writes by the show's creator Gene Roddenberry. The episode was directed by Cliff Bole, and saw the return of John de Lancie as Q.

Set in the 24th century, the series follows the adventures of the crew of the Starfleet starship Enterprise. In this episode, Q returns to the USS Enterprise following his original encounter with the crew in "Encounter at Farpoint". Q transports the bridge crew to a landscape where they are attacked by humanoids and grants Commander Riker (Jonathan Frakes) the powers of a member of the Q Continuum, which he is forced to use to resurrect both Worf (Michael Dorn) and Wesley (Wil Wheaton). Riker promises never to use the powers again, but after a rescue mission he breaks down and grants each of the bridge crew a wish, which they refuse, with Riker subsequently rejecting his new powers. Q is recalled to the Continuum in failure.

Writer Maurice Hurley requested that he be credited under the pseudonym C.J. Holland in protest against Roddenberry's re-writes, which he later regretted. The problems with the scripting of the episode changed the way the staff handled subsequent script developments for the series. Bole subsequently praised the abilities of de Lancie during the course of filming the episode. Reviewers thought that while the episode was predictable, the relationship between Q and Picard (Patrick Stewart) was praised, and "Hide and Q" received average overall scores.

Hypothetical star

A hypothetical star is a star, or type of star, that is speculated to exist but has yet to be definitively observed. Hypothetical types of stars have been conjectured to exist, have existed or will exist in the future universe.

Isotoxal figure

In geometry, a polytope (for example, a polygon or a polyhedron), or a tiling, is isotoxal or edge-transitive if its symmetries act transitively on its edges. Informally, this means that there is only one type of edge to the object: given two edges, there is a translation, rotation and/or reflection that will move one edge to the other, while leaving the region occupied by the object unchanged.

The term isotoxal is derived from the Greek τοξον meaning arc.

Laver table

In mathematics, Laver tables (named after Richard Laver, who discovered them towards the end of the 1980s in connection with his works on set theory) are tables of numbers that have certain properties. They occur in the study of racks and quandles.

List of isotoxal polyhedra and tilings

In geometry, isotoxal polyhedra and tilings are edge-transitive. Regular polyhedra are isohedral (face-transitive), isogonal (vertex-transitive) and isotoxal. Quasiregular polyhedra are isogonal and isotoxal, but not isohedral; their duals are isohedral and isotoxal, but not isogonal.

Lockheed YO-3

The Lockheed YO-3 "Quiet Star" was an American single-engined, propeller-driven aircraft that was developed for battlefield observation during the Vietnam War. It was designed to be as quiet as possible, and was intended to observe troop movements in near-silence during the hours of darkness.

Non-topological soliton

In quantum field theory, a non-topological soliton (NTS) is a field configuration possessing, contrary to a topological one, a conserved Noether charge and stable against transformation into usual particles of this field for the following reason. For fixed charge Q, the mass sum of Q free particles exceeds the energy (mass) of the NTS so that the latter is energetically favorable to exist.

The interior region of an NTS is occupied by vacuum different from the ambient vacuum. The vacuums are separated by the surface of the NTS representing a domain wall configuration (topological defect), which also appears in field theories with broken discrete symmetry. Infinite domain walls contradict cosmology, but the surface of an NTS is closed and finite, so its existence would not be contradictory. If the topological domain wall is closed, it shrinks because of wall tension; however, due to the structure of the NTS surface, it does not shrink since the decrease of the NTS volume would increase its energy.

Outline of Star Trek

The following outline is provided as an overview of and topical guide to Star Trek:

Star Trek is an American science fiction entertainment franchise, created by Gene Roddenberry, which started in 1966 with the television series Star Trek (now known as Star Trek: The Original Series). With spin-offs, the franchise now includes seven television series (six live action, and one animated) totaling 740 episodes across 31 television seasons, as well as 13 feature films. The Star Trek franchise also includes a large number of novels, comic books, video games and other materials, which are generally considered non-canon.

Q (Star Trek)

Q is a fictional character as well as the name of a race in Star Trek appearing in the Next Generation, Deep Space Nine, and Voyager series, as well as in related media. The most familiar Q is portrayed by John de Lancie. He is an extra-dimensional being of unknown origin who possesses immeasurable power over normal human notions of time, space, the laws of physics, and reality itself, being capable of altering it to his whim. Despite his vast knowledge and experience spanning untold eons (and much to the exasperation of the object(s) of his obsession), he is not above practical jokes for his own personal amusement, for a Machiavellian and manipulative purpose, or to prove a point. He is said to be almost omnipotent, and he is continually evasive regarding his true motivations.

The name "Q" applies to the names of the individuals portrayed (all "male" and "female" characters refer to each other as "Q"), it also applies to the name of their race and to the "Q Continuum" itself – an alternate dimension accessible to only the Q and their "invited" guests. The true nature of the realm is said to be beyond the comprehension of "lesser beings" such as humans, therefore it is shown to humans only in ways they can understand.

Beginning with the pilot episode "Encounter at Farpoint" of The Next Generation, Q became a recurring character, with pronounced comedic and dramatic chemistry with Jean-Luc Picard. He serves as a major antagonist throughout The Next Generation, playing a pivotal role in both the first and final episodes. Q is initially presented as a cosmic force judging humanity to see if it is becoming a threat to the universe, but as the series progresses, his role morphs more into one of a teacher to Picard and the human race generally – albeit often in seemingly destructive or disruptive ways, subject to his own amusement. Other times, notably during "Deja Q" and Voyager, Q appears to the crew seeking assistance.

Gene Roddenberry chose the letter "Q" in honor of his friend, Janet Quarton.

Schweizer X-26 Frigate

The X-26 Frigate is the longest-lived of the X-plane programs. The program included the X-26A Frigate sailplane and the motorized X-26B Quiet Thruster versions: QT-2, QT-2PC, and QT-2PCII. All were based on the Schweizer SGS 2-32 sailplane.

Spherical tokamak

A spherical tokamak is a type of fusion power device based on the tokamak principle. It is notable for its very narrow profile, or aspect ratio. A traditional tokamak has a toroidal confinement area that gives it an overall shape similar to a donut, complete with a large hole in the middle. The spherical tokamak reduces the size of the hole as much as possible, resulting in a plasma shape that is almost spherical, often compared with a cored apple. The spherical tokamak is sometimes referred to as a spherical torus and often shortened to ST.

The spherical tokamak is an offshoot of the conventional tokamak design. Proponents claim that it has a number of substantial practical advantages over these devices. For this reason the ST has generated considerable interest since the late 1980s. However, development remains effectively one generation behind traditional tokamak efforts like JET. Major experiments in the ST field include the pioneering START and MAST at Culham in the UK, the US's NSTX-U and Russian Globus-M.

Research has investigated whether spherical tokamaks are a route to lower cost reactors. Further research is needed to better understand how such devices scale. Even in the event that STs do not lead to lower cost approaches to power generation, they are still lower cost in general; this makes them attractive devices for studying plasma physics, or as high-energy neutron sources.


The n-gonal trapezohedron, antidipyramid, antibipyramid or deltohedron is the dual polyhedron of an n-gonal antiprism. With a highest symmetry, its 2n faces are congruent kites (also called trapezia or deltoids). The faces are symmetrically staggered.

The n-gon part of the name does not reference the faces here but arrangement of vertices around an axis of symmetry. The dual n-gonal antiprism has two actual n-gon faces.

An n-gonal trapezohedron can be dissected into two equal n-gonal pyramids and an n-gonal antiprism.

True Q

"True Q" is the 132nd episode of the American syndicated science fiction television series Star Trek: The Next Generation, the sixth episode of the sixth season.

In this episode, a young woman coming aboard evidences superhuman abilities and is investigated by Q, who claims she is also a Q.

Star systems
Related articles
Physics of

This page is based on a Wikipedia article written by authors (here).
Text is available under the CC BY-SA 3.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.