Random Articles (Page 2)
Have a deep view into what people are curious about.
π Proving something exists nonconstructively using probability.
The probabilistic method is a nonconstructive method, primarily used in combinatorics and pioneered by Paul ErdΕs, for proving the existence of a prescribed kind of mathematical object. It works by showing that if one randomly chooses objects from a specified class, the probability that the result is of the prescribed kind is strictly greater than zero. Although the proof uses probability, the final conclusion is determined for certain, without any possible error.
This method has now been applied to other areas of mathematics such as number theory, linear algebra, and real analysis, as well as in computer science (e.g. randomized rounding), and information theory.
Discussed on
- "Proving something exists nonconstructively using probability." | 2009-05-27 | 26 Upvotes 8 Comments
π Konstantin Tsiolkovsky
Konstantin Eduardovich Tsiolkovsky (Russian: ΠΠΎΠ½ΡΡΠ°Π½ΡΠΈΜΠ½ ΠΠ΄ΡΠ°ΜΡΠ΄ΠΎΠ²ΠΈΡ Π¦ΠΈΠΎΠ»ΠΊΠΎΜΠ²ΡΠΊΠΈΠΉ; 17 SeptemberΒ [O.S. 5 September]Β 1857 β 19 September 1935) was a Russian and Soviet rocket scientist who pioneered astronautics. Along with the Frenchman Robert Esnault-Pelterie, the Germans Hermann Oberth and Fritz von Opel, and the American Robert H. Goddard, he is one of the founding fathers of modern rocketry and astronautics. His works later inspired leading Soviet rocket-engineers Sergei Korolev and Valentin Glushko, who contributed to the success of the Soviet space program.
Tsiolkovsky spent most of his life in a log house on the outskirts of Kaluga, about 200Β km (120Β mi) southwest of Moscow. A recluse by nature, his unusual habits made him seem bizarre to his fellow townsfolk.
Discussed on
- "Konstantin Tsiolkovsky" | 2023-02-22 | 180 Upvotes 97 Comments
π List of Java virtual machines
This article provides non-exhaustive lists of Java SE Java virtual machines (JVMs). It does not include a large number of Java ME vendors. Note that Java EE runs on the standard Java SE JVM but that some vendors specialize in providing a modified JVM optimized for Java EE applications. A large amount of Java development work takes place on Windows, Solaris, Linux and FreeBSD, primarily with the Oracle JVMs. Note the further complication of different 32-bit/64-bit varieties.
The primary reference Java VM implementation is HotSpot, produced by Oracle Corporation.
Discussed on
- "List of Java virtual machines" | 2014-08-07 | 25 Upvotes 7 Comments
π Audie Murphy
Audie Leon Murphy (20 June 1925Β β 28 May 1971) was an American soldier, actor, and songwriter. He was widely celebrated as the most decorated American combat soldier of World War II, and has been described as the most highly decorated soldier in U.S. history. He received every military combat award for valor available from the United States Army, as well as French and Belgian awards for heroism. Murphy received the Medal of Honor for valor that he demonstrated at the age of 19 for single-handedly holding off a company of German soldiers for an hour at the Colmar Pocket in France in January 1945, before leading a successful counterattack while wounded and out of ammunition.
Murphy was born into a large family of sharecroppers in Hunt County, Texas. After his father abandoned them, his mother died when he was a teenager. Murphy left school in fifth grade to pick cotton and find other work to help support his family; his skill with a hunting rifle helped feed his family.
After the attack on Pearl Harbor in 1941, Murphy's older sister helped him to falsify documentation about his birthdate in order to meet the minimum age requirement for enlisting in the military. Turned down initially for being underweight by the Army, Navy, and the Marine Corps, he eventually was able to enlist in the Army. He first saw action in the 1943 Allied invasion of Sicily; then in 1944 he participated in the Battle of Anzio, the liberation of Rome, and the invasion of southern France. Murphy fought at MontΓ©limar and led his men on a successful assault at L'Omet quarry near Cleurie in northeastern France in October. Despite suffering from multiple illnesses and wounds throughout his service, Murphy became one of the most praised and decorated soldiers of World War II. He is credited with killing 241 enemy soldiers.
After the war, Murphy embarked on a 21-year acting career. He played himself in the 1955 autobiographical film To Hell and Back, based on his 1949 memoirs of the same name, but most of his roles were in Westerns. He made guest appearances on celebrity television shows and starred in the series Whispering Smith. Murphy was a fairly accomplished songwriter. He bred quarter horses in California and Arizona, and became a regular participant in horse racing.
Because Murphy had what would today be described as post-traumatic stress disorder (PTSD), then known as "battle fatigue", he slept with a loaded handgun under his pillow. He looked for solace in addictive sleeping pills. In his last few years, he was plagued by money problems but refused offers to appear in alcohol and cigarette commercials because he did not want to set a bad example. Murphy died in a plane crash in Virginia in 1971, shortly before his 46th birthday. He was interred with military honors at Arlington National Cemetery, where his grave is one of the most visited.
Discussed on
- "Audie Murphy" | 2024-06-17 | 15 Upvotes 2 Comments
π Philosophus Autodidactus
αΈ€ayy ibn YaqαΊΔn (Arabic: ΨΩ Ψ¨Ω ΩΩΨΈΨ§Ω, lit.β'Alive son of Awake'; also known as Hai Eb'n Yockdan) is an Arabic philosophical novel and an allegorical tale written by Ibn Tufail (c.β1105 β 1185) in the early 12th century in Al-Andalus. Names by which the book is also known include the Latin: Philosophus Autodidactus ('The Self-Taught Philosopher'); and English: The Improvement of Human Reason: Exhibited in the Life of Hai Ebn Yokdhan. αΈ€ayy ibn YaqαΊΔn was named after an earlier Arabic philosophical romance of the same name, written by Avicenna during his imprisonment in the early 11th century, even though both tales had different stories. The novel greatly inspired Islamic philosophy as well as major Enlightenment thinkers. It is the third most translated text from Arabic, after the Quran and the One Thousand and One Nights.
Discussed on
- "Philosophus Autodidactus" | 2024-04-25 | 73 Upvotes 29 Comments
π Cosmopolitan Railway
The Cosmopolitan Railway was a proposed global railroad network advocated by William Gilpin, formerly the first territorial governor of Colorado (1861β62), in his 1890 treatise Cosmopolitan Railway: Compacting and Fusing Together All the World's Continents. Gilpin named his capital city of Denver as the "railroad centre of the West".
Discussed on
- "Cosmopolitan Railway" | 2022-03-13 | 43 Upvotes 16 Comments
π Entity realism
Entity realism (also selective realism), sometimes equated with referential realism, is a philosophical position within the debate about scientific realism. It is a variation of realism (independently proposed by Stanford School philosophers Nancy Cartwright and Ian Hacking in 1983) that restricts warranted belief to only certain entities.
π Judy arrays are patented
In computer science, a Judy array is a data structure implementing a type of associative array with high performance and low memory usage. Unlike most other key-value stores, Judy arrays use no hashing, leverage compression on their keys (which may be integers or strings), and can efficiently represent sparse data, that is, they may have large ranges of unassigned indices without greatly increasing memory usage or processing time. They are designed to remain efficient even on structures with sizes in the peta-element range, with performance scaling on the order of O(log n). Roughly speaking, Judy arrays are highly optimized 256-ary radix trees.
Judy trees are usually faster than AVL trees, B-trees, hash tables and skip lists because they are highly optimized to maximize usage of the CPU cache. In addition, they require no tree balancing and no hashing algorithm is used.
The Judy array was invented by Douglas Baskins and named after his sister.
Discussed on
- "Judy arrays are patented" | 2013-01-11 | 42 Upvotes 56 Comments
π Eastgate Centre, Harare
The Eastgate Centre is a shopping centre and office block in central Harare, Zimbabwe whose architect is Mick Pearce. Designed to be ventilated and cooled by entirely natural means, it was probably the first building in the world to use natural cooling to this level of sophistication. It opened in 1996 on Robert Mugabe Avenue and Second Street, and provides 5,600 mΒ² of retail space, 26,000 mΒ² of office space and parking for 450 cars.
Discussed on
- "Eastgate Centre, Harare" | 2019-07-13 | 201 Upvotes 61 Comments
π Laudatio Turiae
Laudatio Turiae ("In praise of Turia") is a tombstone engraved with a carved epitaph that is a husband's eulogy of his wife. It was made in the late 1st century BC. It portrays the love of a husband for his loyal wife.
Discussed on
- "Laudatio Turiae" | 2024-05-06 | 103 Upvotes 8 Comments