Have a deep view into what people are curious about.

🔗 Mathematics

The ant on a rubber rope is a mathematical puzzle with a solution that appears counterintuitive or paradoxical. It is sometimes given as a worm, or inchworm, on a rubber or elastic band, but the principles of the puzzle remain the same.

The details of the puzzle can vary, but a typical form is as follows:

An ant starts to crawl along a taut rubber rope 1 km long at a speed of 1 cm per second (relative to the rubber it is crawling on). At the same time, the rope starts to stretch uniformly at a constant rate of 1 km per second, so that after 1 second it is 2 km long, after 2 seconds it is 3 km long, etc. Will the ant ever reach the end of the rope?

At first consideration it seems that the ant will never reach the end of the rope, but in fact it does. (In the form stated above, it would take 8.9×10⁴³⁴²¹ years.) Whatever the length of the rope and the relative speeds of the ant and the stretching, provided that the ant's speed and the stretching remain steady, the ant will always be able to reach the end given sufficient time. Once the ant has begun moving, the rubber rope is stretching both in front of and behind the ant, conserving the proportion of the rope already walked by the ant and enabling the ant to make continual progress.

🔗 Color 🔗 Physiology

Eigengrau (German: "intrinsic gray", lit. "own gray"; pronounced [ˈʔaɪ̯gn̩ˌgʁaʊ̯]), also called Eigenlicht (Dutch and German: "own light"), dark light, or brain gray, is the uniform dark gray background that many people report seeing in the absence of light. The term Eigenlicht dates back to the nineteenth century, but has rarely been used in recent scientific publications. Common scientific terms for the phenomenon include "visual noise" or "background adaptation". These terms arise due to the perception of an ever-changing field of tiny black and white dots seen in the phenomenon.

Eigengrau is perceived as lighter than a black object in normal lighting conditions, because contrast is more important to the visual system than absolute brightness. For example, the night sky looks darker than Eigengrau because of the contrast provided by the stars.

🔗 Mathematics

Reverse mathematics is a program in mathematical logic that seeks to determine which axioms are required to prove theorems of mathematics. Its defining method can briefly be described as "going backwards from the theorems to the axioms", in contrast to the ordinary mathematical practice of deriving theorems from axioms. It can be conceptualized as sculpting out necessary conditions from sufficient ones.

The reverse mathematics program was foreshadowed by results in set theory such as the classical theorem that the axiom of choice and Zorn's lemma are equivalent over ZF set theory. The goal of reverse mathematics, however, is to study possible axioms of ordinary theorems of mathematics rather than possible axioms for set theory.

Reverse mathematics is usually carried out using subsystems of second-order arithmetic, where many of its definitions and methods are inspired by previous work in constructive analysis and proof theory. The use of second-order arithmetic also allows many techniques from recursion theory to be employed; many results in reverse mathematics have corresponding results in computable analysis. Recently, higher-order reverse mathematics has been introduced, in which the focus is on subsystems of higher-order arithmetic, and the associated richer language.

The program was founded by Harvey Friedman (1975, 1976) and brought forward by Steve Simpson. A standard reference for the subject is (Simpson 2009), while an introduction for non-specialists is (Stillwell 2018). An introduction to higher-order reverse mathematics, and also the founding paper, is (Kohlenbach (2005)).

🔗 Skepticism 🔗 Psychology

The Barnum effect, also called the Forer effect, or less commonly, the Barnum-Forer effect, is a common psychological phenomenon whereby individuals give high accuracy ratings to descriptions of their personality that supposedly are tailored specifically to them, that are in fact vague and general enough to apply to a wide range of people. This effect can provide a partial explanation for the widespread acceptance of some paranormal beliefs and practices, such as astrology, fortune telling, aura reading, and some types of personality tests.

These characterizations are often used by practitioners as a con-technique to convince victims that they are endowed with a paranormal gift. Because the assessment statements are so vague, people interpret their own meaning, thus the statement becomes "personal" to them. Also, individuals are more likely to accept negative assessments of themselves if they perceive the person presenting the assessment as a high-status professional.

The term "Barnum effect" was coined in 1956 by psychologist Paul Meehl in his essay Wanted – A Good Cookbook, because he relates the vague personality descriptions used in certain "pseudo-successful" psychological tests to those given by showman P. T. Barnum.

🔗 Internet 🔗 Computing 🔗 Internet culture 🔗 Freedom of speech 🔗 Computing/Software 🔗 Computing/Computer Security 🔗 Popular Culture 🔗 Lincolnshire

The Scunthorpe problem is the unintentional blocking of websites, e-mails, forum posts or search results by a spam filter or search engine because their text contains a string of letters that appear to have an obscene or otherwise unacceptable meaning. Names, abbreviations, and technical terms are most often cited as being affected by the issue.

The problem arises since computers can easily identify strings of text within a document, but interpreting words of this kind requires considerable ability to interpret a wide range of contexts, possibly across many cultures, which is an extremely difficult task. As a result, broad blocking rules may result in false positives affecting innocent phrases.

🔗 Computing 🔗 Computer science 🔗 Software 🔗 Software/Computing

In 1983, David H. D. Warren designed an abstract machine for the execution of Prolog consisting of a memory architecture and an instruction set. This design became known as the Warren Abstract Machine (WAM) and has become the de facto standard target for Prolog compilers.

🔗 Computing 🔗 Computing/Networking

Sorcerer's Apprentice Syndrome (SAS) is a network protocol flaw in the original versions of TFTP. It was named after Goethe's poem "Der Zauberlehrling" (popularized by the "Sorcerer's Apprentice" segment of the animated film Fantasia), because the details of its operation closely resemble the disaster that befalls the sorcerer's apprentice: the problem resulted in an ever-growing replication of every packet in the transfer.

The problem occurred because of a known failure mode of the internetwork which, through a mistake on the part of the TFTP protocol designers, was not taken into account when the protocol was designed; the failure mode interacted with several details of the mechanisms of TFTP to produce SAS.

🔗 Biography 🔗 Systems 🔗 Biography/arts and entertainment

John Gall (September 18, 1925 – December 15, 2014) was an American author and retired pediatrician. Gall is known for his 1975 book General systemantics: an essay on how systems work, and especially how they fail..., a critique of systems theory. One of the statements from this book has become known as Gall's law.

🔗 Department of Fun

Occasionally, even experienced Wikipedians lose their heads and devote every waking moment to edit warring over the most trivial thing, wasting time debating topics of no practical value, or wrestling over questions whose answers hold no practical consequence. This page documents our lamest examples. It isn't comprehensive or authoritative, but it serves as a showcase of situations where people lose sight of the big picture and obsessively expend huge amounts of energy fighting over something that, in the end, isn't really so important.

Edit warring is believed by some to be important, possibly due to the historical regularity and frequency of the occurrence of these wars. A careful and scholarly study of available archeological evidence has even suggested that edit wars may have recurred on a regular basis going back all the way to the beginning of recorded history, even before the advent of proper writing circa 2001 C.E. (see Wikipedia). In some earlier instances of edit warring, dating back from before the good old days, participants would simply utilize their swords and fight a battle, or later, their guns and fight a duel.

In modern times, physical combat has been outlawed and replaced by the careful inciting of personal attacks, strategic 3RR templating and canvassing, timely notices on WP:AN/I, and (in some cases) marking the changes as a minor edit. Truly, the revolutionary Wikipedia outlook has changed the way things get done. It has changed them from actually getting done to never getting done. On the other hand, nobody gets dispatched (so far!).

🔗 Disaster management 🔗 Medicine 🔗 Viruses 🔗 COVID-19 🔗 Medicine/Pulmonology 🔗 Medicine/Emergency medicine and EMS

A COVID-19 vaccine is a hypothetical vaccine against coronavirus disease 2019 (COVID‑19). Although no vaccine has completed clinical trials, there are multiple attempts in progress to develop such a vaccine. In February 2020, the World Health Organization (WHO) said it did not expect a vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative virus, to become available in less than 18 months. The Coalition for Epidemic Preparedness Innovations (CEPI) – which is organizing a US$2 billion worldwide fund for rapid investment and development of vaccine candidates – indicated in April that a vaccine may be available under emergency use protocols in less than 12 months or by early 2021. On 4 May 2020, the WHO organized a telethon to raise US$8 billion from forty countries to support rapid development of vaccines to prevent COVID-19 infections, also announcing deployment of an international "Solidarity trial" for simultaneous evaluation of several vaccine candidates reaching Phase II-III clinical trials.

By May, 159 vaccine candidates were in development, with five having been initiated in Phase I–II safety and efficacy studies in human subjects, and seven in Phase I trials.