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Faster-than-light Communication
Faster-than-light communication, also called superluminal communication, is a hypothetical process in which information is conveyed at faster-than-light speeds. The current scientific consensus is that faster-than-light communication is not possible, and to date it has not been achieved in any experiment. Faster-than-light communication other than possibly through wormholes is likely impossible because, in a Lorentz-invariant theory, it could be used to transmit information into the past. This would complicate causality, but no theoretical arguments conclusively preclude this possibility. A number of theories and phenomena related to faster-than-light communication have been proposed or studied, including tachyons, neutrinos, quantum nonlocality, wormholes, and quantum tunneling. Proposed mechanisms Tachyons Tachyonic particles are hypothetical particles that travel faster than light, which could conceivably allow for superluminal communication. Because such a particle woul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Information
Information is an Abstraction, abstract concept that refers to something which has the power Communication, to inform. At the most fundamental level, it pertains to the Interpretation (philosophy), interpretation (perhaps Interpretation (logic), formally) of that which may be sensed, or their abstractions. Any natural process that is not completely random and any observable pattern in any Media (communication), medium can be said to convey some amount of information. Whereas digital signals and other data use discrete Sign (semiotics), signs to convey information, other phenomena and artifacts such as analog signals, analogue signals, poems, pictures, music or other sounds, and current (fluid), currents convey information in a more continuous form. Information is not knowledge itself, but the meaning (philosophy), meaning that may be derived from a representation (mathematics), representation through interpretation. The concept of ''information'' is relevant or connected t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Mechanics
Quantum mechanics is the fundamental physical Scientific theory, theory that describes the behavior of matter and of light; its unusual characteristics typically occur at and below the scale of atoms. Reprinted, Addison-Wesley, 1989, It is the foundation of all quantum physics, which includes quantum chemistry, quantum field theory, quantum technology, and quantum information science. Quantum mechanics can describe many systems that classical physics cannot. Classical physics can describe many aspects of nature at an ordinary (macroscopic and Microscopic scale, (optical) microscopic) scale, but is not sufficient for describing them at very small submicroscopic (atomic and subatomic) scales. Classical mechanics can be derived from quantum mechanics as an approximation that is valid at ordinary scales. Quantum systems have Bound state, bound states that are Quantization (physics), quantized to Discrete mathematics, discrete values of energy, momentum, angular momentum, and ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isaac Asimov
Isaac Asimov ( ; – April 6, 1992) was an Russian-born American writer and professor of biochemistry at Boston University. During his lifetime, Asimov was considered one of the "Big Three" science fiction writers, along with Robert A. Heinlein and Arthur C. Clarke. A prolific writer, he wrote or edited more than 500 books. He also wrote an estimated 90,000 letters and postcards. Best known for his hard science fiction, Asimov also wrote mystery fiction, mysteries and fantasy, as well as popular science and other non-fiction. Asimov's most famous work is the ''Foundation (book series), Foundation'' series, the first three books of which won the one-time Hugo Award for "Best All-Time Series" in 1966. His other major series are the ''Galactic Empire series, Galactic Empire'' series and the ''Robot series, Robot'' series. The ''Galactic Empire'' novels are set in the much earlier history of the same fictional universe as the ''Foundation'' series. Later, with ''Foundation an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lensman Series
The ''Lensman'' series is a series of science fiction novels by American author E. E. "Doc" Smith. It was a runner-up for the 1966 Hugo Award for Best All-Time Series, losing to the ''Foundation'' series by Isaac Asimov. Plot The series begins with ''Triplanetary'', beginning two billion years before the present time and continuing into the near future. The universe has no life-forms aside from the ancient Arisians, and few planets besides the Arisians' native world. The peaceful Arisians have foregone physical skills in order to develop contemplative mental power. The underlying assumption for this series, based on theories of stellar evolution extant at the time of the books' writing, is that planets form only rarely, and therefore our First and Second Galaxies, with their many billions of planets, are unique. The Eddorians, a dictatorial, power-hungry race, come into our universe from an alien space-time continuum after observing that our galaxy and a sister galaxy (the Se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Quincunx Of Time
''The Quincunx of Time'' is a short science fiction novel by American writer James Blish. It is an extended version of a short story entitled "Beep", published by ''Galaxy Science Fiction'' magazine in 1954. The novel form was first published in 1973. Setting Late in the 21st century, a device called the ''Dirac communicator''James Blish was fascinated by the work of P.A.M. Dirac and P.M.S. Blackett. His works make frequent reference to one or the other as the source for various devices. The spindizzy device is based on Blackett's theories. The Dirac communicator is based on Dirac's prediction of the positron. It also appears to refer to quantum entanglement. promises instantaneous communication across interstellar distances. This would allow Earth security, headed by one Robin Weinbaum, to keep the peace. Before one of the devices can even reach a far-away system, someone starts producing predictions that suggest they have advance knowledge of Dirac communications. Ev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Blish
James Benjamin “Jimmy” Blish () was an American science fiction and fantasy writer. He is best known for his ''Cities in Flight'' novels and his series of ''Star Trek'' novelizations written with his wife, J. A. Lawrence. His novel ''A Case of Conscience'' won the Hugo Award. He is credited with creating the term "gas giant" to refer to large planetary bodies. His first published stories appeared in ''Super Science Stories'' and ''Amazing Stories''. Blish wrote literary criticism of science fiction using the pen name William Atheling Jr. His other pen names included Donald Laverty, John MacDougal, and Arthur Lloyd Merlyn. Life Blish was born on May 23, 1921, at East Orange, New Jersey. While in high school, Blish self-published a fanzine, called ''The Planeteer'', using a hectograph. The fanzine ran for six issues. Blish was a member of the Futurians. Blish attended meetings of the Futurian Science Fiction Society in New York City during this period. Futurian members ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spacecraft
A spacecraft is a vehicle that is designed spaceflight, to fly and operate in outer space. Spacecraft are used for a variety of purposes, including Telecommunications, communications, Earth observation satellite, Earth observation, Weather satellite, meteorology, navigation, space colonization, Planetary science, planetary exploration, and Space transport, transportation of Human spaceflight, humans and cargo spacecraft, cargo. All spacecraft except single-stage-to-orbit vehicles cannot get into space on their own, and require a launch vehicle (carrier rocket). On a sub-orbital spaceflight, a space vehicle enters space and then returns to the surface without having gained sufficient energy or velocity to make a full Geocentric orbit, Earth orbit. For orbital spaceflights, spacecraft enter closed orbits around the Earth or around other Astronomical object, celestial bodies. Spacecraft used for human spaceflight carry people on board as crew or passengers from start or on orbit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Negative Energy
Negative energy is a concept used in physics to explain the nature of certain fields, including the gravitational field and various quantum field effects. Gravitational energy Gravitational energy, or gravitational potential energy, is the potential energy a massive object has because it is within a gravitational field. In classical mechanics, two or more masses always have a gravitational potential. Conservation of energy requires that this gravitational field energy is always negative, so that it is zero when the objects are infinitely far apart. As two objects move apart and the distance between them approaches infinity, the gravitational force between them approaches zero from the positive side of the real number line and the gravitational potential approaches zero from the negative side. Conversely, as two massive objects move towards each other, the motion accelerates under gravity causing an increase in the (positive) kinetic energy of the system and, in order to conser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Negative Mass
In theoretical physics, negative mass is a hypothetical type of exotic matter whose mass is of opposite sign to the mass of normal matter, e.g. −1 kg. Such matter would violate one or more energy conditions and exhibit strange properties such as the oppositely oriented acceleration for an applied force orientation. It is used in certain speculative hypothetical technologies such as time travel to the past and future, construction of traversable artificial wormholes, which may also allow for time travel, Krasnikov tubes, the Alcubierre drive, and potentially other types of faster-than-light warp drives. Currently, the closest known real representative of such exotic matter is a region of negative pressure density produced by the Casimir effect. In cosmology In December 2018, astrophysicist Jamie Farnes from the University of Oxford proposed a " dark fluid" theory, related, in part, to notions of gravitationally repulsive negative masses, presented earlier by Albert Ein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exotic Matter
There are several proposed types of exotic matter: * Hypothetical particles and states of matter that have not yet been encountered, but whose properties would be within the realm of mainstream physics if found to exist. * Several particles whose existence has been experimentally confirmed that are conjectured to be exotic hadrons and within the Standard Model. * State of matter, States of matter that are not commonly encountered, such as Bose–Einstein condensates, fermionic condensates, nuclear matter, quantum spin liquid, string-net liquid, supercritical fluid, color-glass condensate, quark–gluon plasma, Rydberg matter, Rydberg polaron, photonic matter, Wigner crystal, Superfluidity, Superfluid and time crystal but whose properties are entirely within the realm of mainstream physics. * Forms of matter that are poorly understood, such as dark matter and mirror matter. * Ordinary matter that when placed under high pressure, may result in dramatic changes in its physical or c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
No-communication Theorem
In physics, the no-communication theorem (also referred to as the no-signaling principle) is a no-go theorem in quantum information theory. It asserts that during the measurement of an entangled quantum state, it is impossible for one observer to transmit information to another observer, regardless of their spatial separation. This conclusion preserves the principle of causality in quantum mechanics and ensures that information transfer does not violate special relativity by exceeding the speed of light. The theorem is significant because quantum entanglement creates correlations between distant events that might initially appear to enable faster-than-light communication. The no-communication theorem establishes conditions under which such transmission is impossible, thus resolving paradoxes like the Einstein-Podolsky-Rosen (EPR) paradox and addressing the violations of local realism observed in Bell's theorem. Specifically, it demonstrates that the failure of local realism doe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Axiomatic Quantum Field Theory
Axiomatic quantum field theory is a mathematical discipline which aims to describe quantum field theory in terms of rigorous axioms. It is strongly associated with functional analysis and operator algebras, but has also been studied in recent years from a more geometric and functorial perspective. There are two main challenges in this discipline. First, one must propose a set of axioms which describe the general properties of any mathematical object that deserves to be called a "quantum field theory". Then, one gives rigorous mathematical constructions of examples satisfying these axioms. Analytic approaches Wightman axioms The first set of axioms for quantum field theories, known as the Wightman axioms, were proposed by Arthur Wightman in the early 1950s. These axioms attempt to describe QFTs on flat Minkowski spacetime by regarding quantum fields as operator-valued distributions acting on a Hilbert space. In practice, one often uses the Wightman reconstruction theorem, whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
