Topic: Alternative Views
The Alcubierre drive, Alcubierre warp drive, or Alcubierre metric (referring to metric tensor) is a speculative idea based on a solution of Einstein's field equations in general relativity as proposed by Mexican theoretical physicist Miguel Alcubierre, by which a spacecraft could achieve apparent faster-than-light travel if a configurable energy-density field lower than that of vacuum (that is, negative mass) could be created.
Rather than exceeding the speed of light within a local reference frame, a spacecraft would traverse distances by contracting space in front of it and expanding space behind it, resulting in effective faster-than-light travel. Objects cannot accelerate to the speed of light within normal spacetime; instead, the Alcubierre drive shifts space around an object so that the object would arrive at its destination faster than light would in normal space without breaking any physical laws.
Although the metric proposed by Alcubierre is consistent with the Einstein field equations, construction of such a drive is not necessarily possible. The proposed mechanism of the Alcubierre drive implies a negative energy density and therefore requires exotic matter. So if exotic matter with the correct properties cannot exist, then the drive could not be constructed. At the close of his original article, however, Alcubierre argued (following an argument developed by physicists analyzing traversable wormholes) that the Casimir vacuum between parallel plates could fulfill the negative-energy requirement for the Alcubierre drive.
Another possible issue is that, although the Alcubierre metric is consistent with Einstein's equations, general relativity does not incorporate quantum mechanics. Some physicists have presented arguments to suggest that a theory of quantum gravity (which would incorporate both theories) would eliminate those solutions in general relativity that allow for backwards time travel (see the chronology protection conjecture) and thus make the Alcubierre drive invalid.
- "Alcubierre drive" | 2018-08-12 | 166 Upvotes 125 Comments
The Antikythera mechanism (, ) is an ancient hand powered Greek analogue computer which has also been described as the first example of such device used to predict astronomical positions and eclipses for calendar and astrological purposes decades in advance. It could also be used to track the four-year cycle of athletic games which was similar to an Olympiad, the cycle of the ancient Olympic Games.
This artefact was retrieved from the sea in 1901, and identified on 17 May 1902 as containing a gear by archaeologist Valerios Stais, among wreckage retrieved from a shipwreck off the coast of the Greek island Antikythera. The instrument is believed to have been designed and constructed by Greek scientists and has been variously dated to about 87 BC, or between 150 and 100 BC, or to 205 BC, or to within a generation before the shipwreck, which has been dated to approximately 70–60 BC.
The device, housed in the remains of a 34 cm × 18 cm × 9 cm (13.4 in × 7.1 in × 3.5 in) wooden box, was found as one lump, later separated into three main fragments which are now divided into 82 separate fragments after conservation efforts. Four of these fragments contain gears, while inscriptions are found on many others. The largest gear is approximately 14 centimetres (5.5 in) in diameter and originally had 223 teeth.
It is a complex clockwork mechanism composed of at least 30 meshing bronze gears. A team led by Mike Edmunds and Tony Freeth at Cardiff University used modern computer x-ray tomography and high resolution surface scanning to image inside fragments of the crust-encased mechanism and read the faintest inscriptions that once covered the outer casing of the machine.
Detailed imaging of the mechanism suggests that it had 37 gear wheels enabling it to follow the movements of the Moon and the Sun through the zodiac, to predict eclipses and even to model the irregular orbit of the Moon, where the Moon's velocity is higher in its perigee than in its apogee. This motion was studied in the 2nd century BC by astronomer Hipparchus of Rhodes, and it is speculated that he may have been consulted in the machine's construction.
The knowledge of this technology was lost at some point in antiquity. Similar technological works later appeared in the medieval Byzantine and Islamic worlds, but works with similar complexity did not appear again until the development of mechanical astronomical clocks in Europe in the fourteenth century. All known fragments of the Antikythera mechanism are now kept at the National Archaeological Museum in Athens, along with a number of artistic reconstructions and replicas of the mechanism to demonstrate how it may have looked and worked.
The Baghdad Battery or Parthian Battery is a set of three artifacts which were found together: a ceramic pot, a tube of copper, and a rod of iron. It was discovered in modern Khujut Rabu, Iraq, close to the metropolis of Ctesiphon, the capital of the Parthian (150 BC – 223 AD) and Sasanian (224–650 AD) empires of Persia, and it is considered to date from either of these periods.
Its origin and purpose remain unclear. It was hypothesized by some researchers that the object functioned as a galvanic cell, possibly used for electroplating, or some kind of electrotherapy, but there is no electroplated object known from this period. An alternative explanation is that it functioned as a storage vessel for sacred scrolls.
- "The Baghdad Battery" | 2019-04-28 | 76 Upvotes 19 Comments
Bicameralism (the condition of being divided into "two-chambers") is a hypothesis in psychology that argues that the human mind once operated in a state in which cognitive functions were divided between one part of the brain which appears to be "speaking", and a second part which listens and obeys—a bicameral mind. The term was coined by Julian Jaynes, who presented the idea in his 1976 book The Origin of Consciousness in the Breakdown of the Bicameral Mind, wherein he made the case that a bicameral mentality was the normal and ubiquitous state of the human mind as recently as 3,000 years ago, near the end of the Mediterranean bronze age.
- "Bicameralism (Psychology)" | 2019-07-06 | 51 Upvotes 29 Comments
The Biefeld–Brown effect is an electrical phenomenon that produces an ionic wind that transfers its momentum to surrounding neutral particles. It describes a force observed on an asymmetric capacitor when high voltage is applied to the capacitor's electrodes. Once suitably charged up to high DC potentials, a thrust at the negative terminal, pushing it away from the positive terminal, is generated. The effect was named by inventor Thomas Townsend Brown who claimed that he did a series of experiments with professor of astronomy Paul Alfred Biefeld, a former teacher of Brown whom Brown claimed was his mentor and co-experimenter at Denison University in Ohio.
The use of an asymmetric capacitor, with the negative electrode being larger than the positive electrode, allowed for more thrust to be produced in the direction from the low-flux to the high-flux region compared to a conventional capacitor. These asymmetric capacitors became known as Asymmetrical Capacitor Thrusters (ACT). The Biefeld–Brown effect can be observed in ionocrafts and lifters, which utilize the effect to produce thrust in the air without requiring any combustion or moving parts.
In his 1960 patent titled "Electrokinetic Apparatus," Brown refers to electrokinesis to describe the Biefeld–Brown effect, linking the phenomenon to the field of electrohydrodynamics (EHD). Brown also believed the Biefeld–Brown effect could produce an anti-gravity force, referred to as "electrogravitics" based on it being an electricity/gravity phenomenon. However, there is little evidence that supports Brown's claim on the effect's anti-gravity properties.
- "Biefeld–Brown effect" | 2014-10-26 | 27 Upvotes 3 Comments
The Business Plot was a political conspiracy in 1933 in the United States. Retired Marine Corps Major General Smedley Butler revealed that wealthy businessmen were plotting to create a fascist veterans' organization with Butler as its leader and use it in a coup d'état to overthrow President Franklin D. Roosevelt. In 1934, Butler testified before the United States House of Representatives Special Committee on Un-American Activities (the "McCormack–Dickstein Committee") on these revelations. No one was prosecuted.
At the time of the incidents, news media dismissed the plot, with a New York Times editorial characterizing it as a "gigantic hoax". While historians have not accepted the notion of a plot, they agree that Butler described one.
- "Business Plot" | 2020-01-10 | 24 Upvotes 2 Comments
In the field of psychology, the Dunning–Kruger effect is a cognitive bias in which people assess their cognitive ability as greater than it is. It is related to the cognitive bias of illusory superiority and comes from the inability of people to recognize their lack of ability. Without the self-awareness of metacognition, people cannot objectively evaluate their competence or incompetence.
As described by social psychologists David Dunning and Justin Kruger, the cognitive bias of illusory superiority results from an internal illusion in people of low ability and from an external misperception in people of high ability; that is, "the miscalibration of the incompetent stems from an error about the self, whereas the miscalibration of the highly competent stems from an error about others."
- "Why less competent may rate their own ability higher than more competent" | 2010-04-22 | 44 Upvotes 18 Comments
- "Dunning-Kruger effect" | 2010-01-19 | 33 Upvotes 11 Comments
The eight-circuit model of consciousness is a hypothesis by Timothy Leary, and later expanded on by Robert Anton Wilson and Antero Alli, that "suggested eight periods [circuits] and twenty-four stages of neurological evolution". The eight circuits, or eight "brains" as referred by other authors, operate within the human nervous system, each corresponding to its own imprint and direct experience of reality. Leary and Alli include three stages for each circuit that details developmental points for each level of consciousness.
The first four circuits deal with life on Earth, and survival of the species. The last four circuits are post-terrestrial, and deal with the evolution of the species, altered states of consciousness, enlightenment, mystical experiences, psychedelic states of mind, and psychic abilities. The proposal suggests that these altered states of consciousness are recently realized, but not widely utilized. Leary describes the first four as "larval circuits", necessary for surviving and functioning in a terrestrial human society, and proposed that the post terrestrial circuits will be useful for future humans who, through a predetermined script, continue to act on their urge to migrate to outer space and live extra-terrestrially. Leary, Wilson, and Alli have written about the idea in depth, and have explored and attempted to define how each circuit operates, both in the lives of individual people and in societies and civilization.
The term "circuit" is equated to a metaphor of the brain being computer hardware, and the wiring of the brain as circuitry.
Leary uses the eight circuits along with recapitulation theory to explain the evolution of the human species, the personal development of an individual, and the biological evolution of all life.
- "8-Circuit Model of Consciousness" | 2011-01-10 | 12 Upvotes 6 Comments
Engines of Creation: The Coming Era of Nanotechnology is a 1986 molecular nanotechnology book written by K. Eric Drexler with a foreword by Marvin Minsky. An updated version was released in 2007. The book has been translated into Japanese, French, Spanish, Italian, Russian, and Chinese.
- "Engines of Creation, by K. Eric Drexler (1986)" | 2019-07-28 | 19 Upvotes 10 Comments
Fan death is a widely held belief in Korean culture, where it is thought that running an electric fan in a closed room with unopened or no windows will prove fatal. Despite no concrete evidence to support the concept, belief in fan death persists to this day in Korea, and also to a lesser extent in Japan and Russia.