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πŸ”— Blind Signature

πŸ”— Cryptography πŸ”— Cryptography/Computer science

In cryptography a blind signature, as introduced by David Chaum, is a form of digital signature in which the content of a message is disguised (blinded) before it is signed. The resulting blind signature can be publicly verified against the original, unblinded message in the manner of a regular digital signature. Blind signatures are typically employed in privacy-related protocols where the signer and message author are different parties. Examples include cryptographic election systems and digital cash schemes.

An often-used analogy to the cryptographic blind signature is the physical act of a voter enclosing a completed anonymous ballot in a special carbon paper lined envelope that has the voter's credentials pre-printed on the outside. An official verifies the credentials and signs the envelope, thereby transferring their signature to the ballot inside via the carbon paper. Once signed, the package is given back to the voter, who transfers the now signed ballot to a new unmarked normal envelope. Thus, the signer does not view the message content, but a third party can later verify the signature and know that the signature is valid within the limitations of the underlying signature scheme.

Blind signatures can also be used to provide unlinkability, which prevents the signer from linking the blinded message it signs to a later un-blinded version that it may be called upon to verify. In this case, the signer's response is first "un-blinded" prior to verification in such a way that the signature remains valid for the un-blinded message. This can be useful in schemes where anonymity is required.

Blind signature schemes can be implemented using a number of common public key signing schemes, for instance RSA and DSA. To perform such a signature, the message is first "blinded", typically by combining it in some way with a random "blinding factor". The blinded message is passed to a signer, who then signs it using a standard signing algorithm. The resulting message, along with the blinding factor, can be later verified against the signer's public key. In some blind signature schemes, such as RSA, it is even possible to remove the blinding factor from the signature before it is verified. In these schemes, the final output (message/signature) of the blind signature scheme is identical to that of the normal signing protocol.

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πŸ”— Microformats

πŸ”— Computing

Microformats (ΞΌF) are predefined HTML markup (like HTML classes) created to serve as descriptive and consistent metadata about elements, designating them as representing a certain type of data (such as contact information, geographic coordinates, events, products, recipes, etc.). They allow software to process the information reliably by having set classes refer to a specific type of data rather than being arbitrary.

Microformats emerged around 2005 and were predominantly designed for use by search engines, web syndication and aggregators such as RSS. Google confirmed in 2020 that it still parses microformats for use in content indexing. Microformats are referenced in several W3C social web specifications, including IndieAuth and Webmention.

Although the content of web pages has been capable of some "automated processing" since the inception of the web, such processing is difficult because the markup elements used to display information on the web do not describe what the information means. Microformats can bridge this gap by attaching semantics, and thereby obviating other, more complicated, methods of automated processing, such as natural language processing or screen scraping. The use, adoption and processing of microformats enables data items to be indexed, searched for, saved or cross-referenced, so that information can be reused or combined.

As of 2013, microformats allow the encoding and extraction of event details, contact information, social relationships and similar information.

Microformats2, abbreviated as mf2, is the updated version of microformats. Mf2 provides an easier way of interpreting HTML structured syntax and vocabularies than the earlier ways that made use of RDFa and microdata.

πŸ”— SΓ€kkijΓ€rven polkka

πŸ”— Finland πŸ”— Roots music

SΓ€kkijΓ€rven polkka ("the SΓ€kkijΓ€rvi polka"), also called the "Karelian-Finnish Polka," is a well-known folk tune from Finland, very popular with Finnish accordionists. It was especially popularized by Viljo "Vili" Vesterinen (1907–1961). The tune was first recorded in SΓ€kkijΓ€rvi (now Kondratyevo in the Leningrad Oblast, Russia), and the lyrics sometimes sung with the tune state that while SΓ€kkijΓ€rvi itself might have been lost (ceded to the Soviet Union in 1940), the Finns at least still had the polka.

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πŸ”— Sailing Stones

πŸ”— California πŸ”— Skepticism πŸ”— Geography πŸ”— Alternative Views πŸ”— Geology

Sailing stones (also known as sliding rocks, walking rocks, rolling stones, and moving rocks), are a geological phenomenon where rocks move and inscribe long tracks along a smooth valley floor without human or animal intervention. The movement of the rocks occurs when large ice sheets a few millimeters thick and floating in an ephemeral winter pond start to break up during sunny days. Frozen during cold winter nights, these thin floating ice panels are driven by wind and shove rocks at speeds up to 5 meters per minute.

Trails of sliding rocks have been observed and studied in various locations, including Little Bonnie Claire Playa in Nevada, and most famously at Racetrack Playa, Death Valley National Park, California, where the number and length of tracks are notable.

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πŸ”— The Triple Revolution

πŸ”— Economics πŸ”— Politics πŸ”— Futures studies πŸ”— Civil Rights Movement

"The Triple Revolution" was an open memorandum sent to U.S. President Lyndon B. Johnson and other government figures on March 22, 1964. Drafted under the auspices of the Center for the Study of Democratic Institutions, it was signed by an array of noted social activists, professors, and technologists who identified themselves as the Ad Hoc Committee on the Triple Revolution. The chief initiator of the proposal was W. H. "Ping" Ferry, at that time a vice-president of CSDI, basing it in large part on the ideas of the futurist Robert Theobald.

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πŸ”— Robert Rayford

πŸ”— Biography πŸ”— AIDS

Robert Rayford (February 3, 1953 – May 15 or 16, 1969), sometimes identified as Robert R. due to his age, was a teenager from Missouri who has been suggested to represent the earliest case of HIV/AIDS in North America based on evidence published in 1988 in which the authors claimed indicated he was "infected with a virus closely related or identical to human immunodeficiency virus type 1." Rayford died of pneumonia, but his other symptoms baffled the doctors who treated him. A study published in 1988 reported the detection of antibodies against HIV. Results of testing for HIV genetic material were reported once at a scientific conference in Australia in 1999; however, the data have never been published in a peer-reviewed medical or scientific journal.

πŸ”— Alan Kay turns 80 today! Happy Birthday!

πŸ”— Biography πŸ”— Apple Inc. πŸ”— Computing πŸ”— Biography/science and academia πŸ”— Disney

Alan Curtis Kay (born May 17, 1940) is an American computer scientist. He has been elected a Fellow of the American Academy of Arts and Sciences, the National Academy of Engineering, and the Royal Society of Arts. He is best known for his pioneering work on object-oriented programming and windowing graphical user interface (GUI) design.

He was the president of the Viewpoints Research Institute before its closure in 2018, and an adjunct professor of computer science at the University of California, Los Angeles. He is also on the advisory board of TTI/Vanguard. Until mid-2005, he was a senior fellow at HP Labs, a visiting professor at Kyoto University, and an adjunct professor at the Massachusetts Institute of Technology (MIT).

Kay is also a former professional jazz guitarist, composer, and theatrical designer, and an amateur classical pipe organist.

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πŸ”— Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo

πŸ”— Linguistics πŸ”— New York (state) πŸ”— New York (state)/Western New York

"Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo" is a grammatically correct sentence in American English, often presented as an example of how homonyms and homophones can be used to create complicated linguistic constructs through lexical ambiguity. It has been discussed in literature in various forms since 1967, when it appeared in Dmitri Borgmann's Beyond Language: Adventures in Word and Thought.

The sentence employs three distinct meanings of the word buffalo:

  • as a proper noun to refer to a specific place named Buffalo, the city of Buffalo, New York, being the most notable;
  • as a verb (uncommon in regular usage) to buffalo, meaning "to bully, harass, or intimidate" or "to baffle"; and
  • as a noun to refer to the animal, bison (often called buffalo in North America). The plural is also buffalo.

An expanded form of the sentence which preserves the original word order is: "Buffalo bison, that other Buffalo bison bully, also bully Buffalo bison."

πŸ”— Bogdanov affair

πŸ”— Biography πŸ”— France πŸ”— Physics πŸ”— Skepticism πŸ”— Physics/Biographies πŸ”— Physics/Publications

The Bogdanov affair was an academic dispute regarding the legitimacy of a series of theoretical physics papers written by French twins Igor and Grichka Bogdanov (alternately spelt Bogdanoff). These papers were published in reputable scientific journals, and were alleged by their authors to culminate in a proposed theory for describing what occurred at and before the Big Bang.

The controversy began in 2002, with an allegation that the twins, celebrities in France for hosting science-themed TV shows, had obtained PhDs with nonsensical work. Rumours spread on Usenet newsgroups that their work was a deliberate hoax intended to target weaknesses in the peer review system that physics journals use to select papers for publication. While the Bogdanov brothers continued to defend the veracity of their work, the debate over whether or not it represented a contribution to physics spread from Usenet to many other Internet forums, eventually receiving coverage in the mainstream media. A Centre national de la recherche scientifique (CNRS) internal report later concluded that their theses had no scientific value.

The incident prompted criticism of the Bogdanovs' approach to science popularization, led to multiple lawsuits, and provoked reflection among physicists as to how and why the peer review system can fail.

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πŸ”— Levenshtein Distance

πŸ”— Computer science

In information theory, linguistics and computer science, the Levenshtein distance is a string metric for measuring the difference between two sequences. Informally, the Levenshtein distance between two words is the minimum number of single-character edits (insertions, deletions or substitutions) required to change one word into the other. It is named after the Soviet mathematician Vladimir Levenshtein, who considered this distance in 1965.

Levenshtein distance may also be referred to as edit distance, although that term may also denote a larger family of distance metrics known collectively as edit distance. It is closely related to pairwise string alignments.

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