click links in text for more info

Principle of relativity

In physics, the principle of relativity is the requirement that the equations describing the laws of physics have the same form in all admissible frames of reference. For example, in the framework of special relativity the Maxwell equations have the same form in all inertial frames of reference. In the framework of general relativity the Maxwell equations or the Einstein field equations have the same form in arbitrary frames of reference. Several principles of relativity have been applied throughout science, whether implicitly or explicitly. Certain principles of relativity have been assumed in most scientific disciplines. One of the most widespread is the belief; these sorts of principles have been incorporated into scientific inquiry at the most fundamental of levels. Any principle of relativity prescribes a symmetry in natural law: that is, the laws must look the same to one observer as they do to another. According to a theoretical result called Noether's theorem, any such symmetry will imply a conservation law alongside.

For example, if two observers at different times see the same laws a quantity called energy will be conserved. In this light, relativity principles make testable predictions about how nature behaves, are not just statements about how scientists should write laws. According to the first postulate of the special theory of relativity: Special principle of relativity: If a system of coordinates K is chosen so that, in relation to it, physical laws hold good in their simplest form, the same laws hold good in relation to any other system of coordinates K' moving in uniform translation to K; this postulate defines an inertial frame of reference. The special principle of relativity states that physical laws should be the same in every inertial frame of reference, but that they may vary across non-inertial ones; this principle is used in the theory of special relativity. Its influence in the latter is so strong; the principle requires physical laws to be the same for any body moving at constant velocity as they are for a body at rest.

A consequence is that an observer in an inertial reference frame cannot determine an absolute speed or direction of travel in space, may only speak of speed or direction relative to some other object. The principle does not extend to non-inertial reference frames because those frames do not, in general experience, seem to abide by the same laws of physics. In classical physics, fictitious forces are used to describe acceleration in non-inertial reference frames; the special principle of relativity was first explicitly enunciated by Galileo Galilei in 1632 in his Dialogue Concerning the Two Chief World Systems, using the metaphor of Galileo's ship. Newtonian mechanics added to the special principle several other concepts, including laws of motion, an assertion of an absolute time; when formulated in the context of these laws, the special principle of relativity states that the laws of mechanics are invariant under a Galilean transformation. Joseph Larmor and Hendrik Lorentz discovered that Maxwell's equations, the cornerstone of electromagnetism, were invariant only by a certain change of time and length units.

This left some confusion among physicists, many of whom thought that a luminiferous aether was incompatible with the relativity principle, in the way it was defined by Henri Poincaré: The principle of relativity, according to which the laws of physical phenomena should be the same, whether for an observer fixed, or for an observer carried along in a uniform movement of translation. In their 1905 papers on electrodynamics, Henri Poincaré and Albert Einstein explained that with the Lorentz transformations the relativity principle holds perfectly. Einstein elevated the principle of relativity to a postulate of the theory and derived the Lorentz transformations from this principle combined with the principle of the independence of the speed of light from the motion of the source; these two principles were reconciled with each other by a re-examination of the fundamental meanings of space and time intervals. The strength of special relativity lies in its derivation from simple, basic principles, including the invariance of the laws of physics under a shift of inertial reference frames and the invariance of the speed of light in a vacuum.

It is, in fact, possible to derive the Lorentz transformations from the principle of relativity alone and obtain the constancy of the speed of light as a consequence. Using only the isotropy of space and the symmetry implied by the principle of special relativity, one can show that the space-time transformations between inertial frames are either Galilean or Lorentzian. In the Lorentzian case, one can obtain relativistic interval conservation and the constancy of the speed of light; the general principle of relativity states:All systems of reference are equivalent with respect to the formulation of the fundamental laws of physics. That is, physical laws are the same in all reference frames—inertial or non-inertial. An accelerated charged particle might emit synchrotron radiation. If we consider now the same accelerated charged particle in its non-inertial rest frame, it emits radiation at rest. Physics in non-inertial reference frames wa

Kōnu District, Hiroshima

Kōnu was a district located in Hiroshima Prefecture. On March 31, 2005, the town of Sōryō, along with the towns of Hiwa, Saijō, Takano and Tōjō, was merged into the expanded city of Shōbara. Therefore, Kōnu District was dissolved as a result of this merger; the previous territory of the district is now the cities of Shōbara, Fuchū, the town of Jinsekikōgen in Jinseki District. Arida Arifuku Inaga Inakusa Ogaya Ozuka Kajita Kamiryōke Kamedani Kiya Kurome Goka Kohori Sakura Shinami Shimoryōke Jōge Tarōmaru Chiwa Tomasu Nakaryōke Nishino Nukuyu Fukuda Futamori Hongō Mizunaga Yasuda Yano April 1, 1889 Municipal status enforced. At this time, they were 29 villages. October 1, 1895 The villages of Inaga, Sakura and Mizunaga merged to form the village of Kiyotake. October 1, 1895 The villages of Kajita, Nishino and Hongō merged to form the village of Kōnu. October 1, 1895 The villages of Arifuku, Ozuka and Futamori merged to form the village of Yoshino. May 7, 1897 The village of Jōge gained town status to become the town of Jōge January 1, 1912 The villages of Inakusa and Shimoryōke merged to form the village of Tabusa.

November 1, 1912 The villages of Arida, Tarōmaru, Chiwa and Yasuda merged to form the village of Kamikawa February 1, 1913 The villages of Kamiryōke, Kurome and Nakaryōke merged to form the village of Ryōke. March 31, 1954 The town of Jōge and the villages of Kiyotake, Yano and parts of、Shinami merged to form the town of Jōge.※The remaining parts of the village of Shinami merged into the village of. March 31, 1955 The villages of Tabusa and Ryōke merged to form the town of Sōryō. March 31, 1955 The villages of Kōnu and parts of Kamikawa merged to form the town of Kōnu ※The remaining parts of the village of Kamikawa merged into the town of Yoshiki. October 10, 1958 The town of Kōnu absorbed the village of Hirosada to create the town of Kōnu April 1, 2004 -The town of Jōge was merged into the expanded city of Fuchū. April 1, 2004 - The town of Kōnu, along with towns of Kisa and Miwa, the villages of Funo and Sakugi, was merged into the expanded city of Miyoshi. March 31, 2005 - The town of Sōryō, along with the towns of Hiwa, Saijō, Takano and Tōjō, was merged into the expanded city of Shōbara.

Therefore, Kōnu District was dissolved as a result of this merger. List of dissolved districts of Japan

Juan Alsina

Juan Ramón Alsina Klingler is a Uruguayan professional footballer who plays as a centre-back for Indonesian club Borneo. Alsina began his career in his homeland with Huracán Buceo, making twelve appearances in three years from 2007. In 2010, Sud América completed the signing of Alsina. After three seasons in the second tier, they won promotion to the Primera División as champions in 2012–13, his first top-flight match arrived on 30 November 2013 during a 1–1 draw versus Defensor Sporting. Thirty appearances in January 2016, Alsina moved to Primera B Nacional on loan with Villa Dálmine, his stint lasted the 2016 -- 17 seasons, appearing fifty-seven times. Having gone back to Sud América, he appeared for the club for the rest of the 2017 Primera División season as they suffered relegation to the Segunda División. Top tier Liverpool subsequently signed Alsina, with the defender participating in the first of six fixtures in February versus Cerro. On 8 August 2018, Alsina returned to Argentina by agreeing a move to Guillermo Brown.

He made his debut in a loss to Brown on 26 August. Alsina scored his first goal for them on 31 March 2019 against Deportivo Morón. After eighteen games for Guillermo Brown, Alsina headed off to Indonesia in August 2019 to join Liga 1 side Borneo. Alsina represented Uruguay at U20 level, including in a friendly against Mexico on 15 May 2008; as of 22 August 2019. Sud AméricaSegunda División: 2012–13 Juan Alsina at Soccerway

Louis Victor Plessier

Louis Victor Plessier was a French general. Joining the army in 1874 Plessier fought in Algeria; as a general in the First World War he led his brigade during the Battle of Mulhouse where he was wounded by German fire. Plessier, hit in three places in his spine, succumbed to his wounds eight days in hospital, he is sometimes regarded as the first French officer to be killed during the war: although four other generals died before he did, his mortal wound was the first. Plessier was born at 11pm on 19 May 1856 at Provins, Seine-et-Marne to Louis Francois Plessier, a lawyer, his wife Victoire Toureau, he volunteered for the French Army on 19 October 1874 and entered the École spéciale militaire de Saint-Cyr on 21 October 1874. Ranked 355th out of his class of 395 cadets, he was commissioned as a sous-lieutenant in the 96th Line Infantry Regiment on 22 September 1876, he attended the French Army's musketry school at Valbonne from 15 October 1877 to 5 January 1878 and was ranked 35th of 55 students.

Promoted to lieutenant on 13 October 1882 in the 121st Line Infantry Regiment, Plessier transferred to the 3rd Marine Infantry Regiment on 5 July 1884. He fought in the Sino-French War in Tonkin and Cambodia between 10 August 1884 and 9 December 1886 and, during an action at Angkor Chey on 12 June 1886, was wounded by a bullet in his left shoulder. Plessier was mentioned in dispatches for his actions in Indo-China, received the Tonkin Expedition commemorative medal and, on 7 July 1887, was appointed a chevalier of the Order of Cambodia. Following his return from the campaign, on 12 November 1886 he was promoted to the rank of capitaine. Plessier transferred to the 27th Infantry Regiment on 12 April 1887 and to the 152nd Infantry Regiment on 12 October 1887 before joining the 1st Foreign Regiment on 8 August 1889 for service in Algeria, he remained in Algeria with the Foreign Legion, where he served as adjutant, until his regiment was sent to form part of the army of occupation in Annam and Tonkin on 3 November 1889.

Plessier returned to French Indo-China where he served until 1 June 1892, whereupon the regiment returned to Algeria, received an appointment in the Order of the Dragon of Annam on 17 October 1892 for his service. He was made a chevalier of the Legion of Honour on 10 July 1891, he remained in Algeria until his transfer back to Metropolitan France with the 51st Infantry Regiment on 11 September 1892. In 1893 Plessier married Alice-Thérèse-Marie-Amélie Dumant and, on 2 October 1895, was promoted to chef de bataillon in the 160th Infantry Regiment. Plessier received promotion to the rank of lieutenant-colonel in the 91st Infantry Regiment on 13 July 1902 and was appointed an officer of the Legion of Honour on 12 July 1905, at which point he was serving as commander of 1st Infantry Group of the Verdun fortress. Plessier was promoted to général de brigade, commanding the 88th Infantry Brigade, on 19 June 1913 and was appointed deputy military governor of Lyon and chief assistant to the commander of Rhône.

Upon the outbreak of war Plessier formed his brigade at Lyon and travelled with it by rail to Grandvillars. The unit took part in the French offensive from Dannemarie towards Mulhouse, part of Germany, saw action at Altkirch and Illfurth. Plessier was leading a reconnaissance expedition at Geisberg Hill, near Zillisheim on 19 August when he was hit by three bullets in his spinal cord, he was transported back to the Desgenettes military hospital in Lyon but died there of his injuries at 2pm on 27 August. Plessier is sometimes considered the first French general to be killed during the war. Plessier was posthumously appointed a commander of the Legion of Honour on 16 May 1915, backdated to 21 August 1914, his death, that of the 600 men of his brigade who died on 19 August, is commemorated by a memorial obelisk in Mulhouse. A street in the 2nd arrondissement of Lyon is named in his honour


Ceridwen or Cerridwen was an enchantress in Welsh medieval legend. She was the mother of a hideous son, a beautiful daughter, Creirwy, her husband was Tegid Foel and they lived near Bala Lake in north Wales. Medieval Welsh poetry refers to her as possessing the cauldron of poetic inspiration and the Tale of Taliesin recounts her swallowing her servant Gwion Bach, reborn through her as the poet Taliesin. Ceridwen is regarded by many modern pagans as the Celtic goddess of rebirth and inspiration; the earliest documented spelling of the name Kerdwin is Cyrridven, which occurs in the Black Book of Carmarthen. Sir Ifor Williams translates this name as "crooked woman", although the precise meaning of the stems cyrrid and cwrr is uncertain. Ben/ven means "woman" or "female". If wen is not a corruption of either of these it may derive from the adjective gwyn, meaning "fair", "beloved", "blessed", or "sacred". Wen is sometimes suffixed to the names of female saints. In 19th century literature and etymology the name Ket and variants were assumed to relate to the goddess Ceridwen.

According to the late medieval Tale of Taliesin, included in some modern editions of the Mabinogion, Ceridwen's son, was hideously ugly - compared with his beautiful sister Creirwy - so Ceridwen sought to make him wise in compensation. She made a potion in her magical cauldron to grant the gift of wisdom and poetic inspiration called Awen; the mixture had to be boiled for a day. She set Morda, a blind man, to tend the fire beneath the cauldron, while Gwion Bach, a young boy, stirred the concoction; the first three drops of liquid from this potion gave wisdom. Three hot drops spilled onto Gwion's thumb, he instinctively put his thumb in his mouth, gained the wisdom and knowledge Ceridwen had intended for her son. Realising that Ceridwen would be angry, Gwion fled. Ceridwen chased him. Using the powers of the potion he turned himself into a hare, she became a greyhound. He jumped into a river, she transformed into an otter. He turned into a bird, he turned into a single grain of corn. She became a hen and, being a goddess, she found and ate him without trouble.

But because of the potion he was not destroyed. When Ceridwen became pregnant, she knew it was Gwion and resolved to kill the child when he was born. However, when he was born, he was so beautiful, she threw him in the ocean instead. The child did not die, but was rescued on a Welsh shore – near Aberdyfi according to most versions of the tale – by a prince named Elffin ap Gwyddno, it has been suggested that Ceridwen first appeared as a simple sorceress character in the Tale of Taliesin. Its earliest surviving text dates from the mid-16th century, but it appears from its language to be a 9th-century composition, according to Hutton. References to Ceridwen and her cauldron found in the work of the 12th century Gogynfeirdd or Poets of the Princes he thus considers derivative works. In them, according to Hutton, Ceridwen is transformed from a sorceress into a goddess of poetry. Citing this and a couple of other examples, Hutton proposes that the Gogynfeirdd created a new mythology not reflective of earlier paganism.

Nonetheless, references to Ceridwen's cauldron are to be found in some of the early mythological poems attributed to the legendary Taliesin in the Book of Taliesin. The Victorian poet Thomas Love Peacock wrote a poem entitled the Cauldron of Ceridwen. Writers identified her as having been a pagan goddess, speculating on her role in a supposed Celtic pantheon. John Rhys in 1878 referred to the Solar Myth theory of Max Müller according to which "Gwenhwyfar and Ceridwen are dawn goddesses." Charles Isaac Elton in 1882 referred to her as a "white fairy". Robert Graves fitted her into his concept of the Threefold Goddess, in which she was interpreted as a form of the destructive side of the goddess. In Wicca, Ceridwen is a goddess of change and rebirth and transformation and her cauldron symbolizes knowledge and inspiration. Finn MacCool and the legend of the Salmon of Knowledge

2015–16 Egypt Cup

The 2015–16 Egypt Cup was the 84th edition of the oldest recognised football tournament in Africa. It was sponsored by Obour Land, known as the Obour Land Cup for sponsorship purposes; the winner qualifies for the 2017 CAF Confederation Cup. Egyptian Premier League side Zamalek were the defending champions and defended their title after they defeated Al Ahly 3–1 in the final; the following is the bracket. Numbers in parentheses next to the match score represent the results of a penalty shoot-out; the draw was held on 28 February 2016 at 14:00 at the EFA headquarters in Cairo. If a match ended as a draw in this round, the two teams go straight to penalty shootout. Matches took place from 19–31 March 2016; the draw was held on 28 February 2016 at 14:00 at the EFA headquarters in Cairo. If a match ended as a draw in this round, the two teams goes to Extra time. If the score remains after the Extra time the two team goes to penalty shootout. Matches took place from 10 April–12 July 2016; the draw was held on 28 February 2016 at 14:00 at the EFA headquarters in Cairo.

If a match ended as a draw in this round, the two teams goes to Extra time. If the score remains after the Extra time the two team goes to penalty shootout. Matches took place from 15 May–1 August 2016; the draw was held on 28 February 2016 at 14:00 at the EFA headquarters in Cairo. If a match ended as a draw in this round, the two teams goes to Extra time. If the score remains after the Extra time the two team goes to penalty shootout. Matches took place on 3 and 4 August 2016; the final took place on 8 August 2016 at Borg El Arab Stadium in Alexandria. Zamalek were the "home" team; the following are the top scorers of the Egypt Cup, sorted first by number of goals, alphabetically if necessary. Goals scored in penalty shoot-outs are not included