History in Jewish thought.

Belief in reincarnation among Jewish mystics first existed in the Ancient World, among differing explanations given of the afterlife, although with a universal belief in an immortal soul. Today, reincarnation is an esoteric belief within many streams of modern Judaism, but is not an essential tenet of traditional Judaism. It is not mentioned in traditional classical sources such as the Hebrew Bible, the classical rabbinic works (Mishnah and Talmud), or Maimonides' 13 principles of faith. Kabbalah (Jewish mysticism), however, teaches a belief in "gilgul", transmigration of souls, and hence the belief is universal in Hasidic Judaism, which regards the Kabbalah as sacred and authoritative.  Among well-known rabbis who rejected the idea of reincarnation are Saadia Gaon, David Kimhi, Hasdai Crescas, Jedaiah ben Abraham Bedersi (early 14th century), Joseph Albo, Abraham ibn Daud and Leon of Modena. Among the Geonim, Hai Gaon argued with Saadia Gaon in favour of "gilgulim".  Rabbis who believed in the idea of reincarnation include, from Medieval times: the mystical leaders Nahmanides and Bahya ben Asher; from the 16th-century: Levi ibn Habib, and from the mystical school of Safed, Shlomo Halevi Alkabetz, Isaac Luria, and his exponent Hayyim ben Joseph Vital; and from the 18th-century: the founder of Hasidic Judaism, the Baal Shem Tov, later Hasidic Masters, and the Lithuanian Jewish Orthodox leader and Kabbalist the Vilna Gaon; and - amongst others - from the 19th/20th-century: Yosef Hayyim author of "Ben Ish Hai".  With the 16th-century rational systemisation of Cordoveran Kabbalah by Alkabetz, and the subsequent new paradigm of Lurianic Kabbalah by Luria, Kabbalah replaced rationalism as the mainstream traditional Jewish theology, both in scholarly circles and in the popular imagination. Isaac Luria taught new explanations of the process of "gilgul" and identification of the reincarnations of historic Jewish figures, which were compiled by Hayyim ben Joseph Vital in his "Shaar HaGilgulim".  The idea of "gilgul" became popular in Jewish folk belief, and is found in much Yiddish literature among Ashkenazi Jews.

In Kabbalah.

The essential Kabbalistic text in regards to "gilgul" is called Sha'ar Ha'Gilgulim ("The Gate of Reincarnations"), based on the work of Rabbi Isaac Luria (and compiled by his disciple, Rabbi Chaim Vital). It describes the deep, complex laws of reincarnation. One concept that arises from Sha'ar Ha'gilgulim is the idea that "gilgul" is paralleled physically by pregnancy. In Kabbalah, any higher spiritual truth is seen to be reflected in lower forms in this physical World. This is because the Divine lifeforce for this realm first descends through the chain of higher realms.

Expression of divine compassion.

In Kabbalistic understanding of "gilgul", reincarnation is not fatalistic or automatic, nor is it essentially a punishment of sin, or reward of virtue. In Judaism, the Heavenly realms could fulfill Maimonides' Principle of faith in Reward and Punishment. Rather, it is concerned with the process of individual Tikkun (Rectification) of the soul. In Kabbalistic interpretation, each Jewish soul is reincarnated enough times only in order to fulfill each of the 613 Mitzvot. The souls of the righteous among the Nations may be assisted through "gilgulim" to fulfil each of their seven mitzvot, the Seven Laws of Noah. As such "gilgul" is an expression of Divine compassion, and is seen as a Heavenly agreement with the individual soul to descend again. This stress on physical performance and perfection of each Mitzvah, is tied to the Lurianic doctrine of Cosmic Tikkun of Creation. In these new teachings, a Cosmic catastrophe occurred at the beginning of Creation called the "Shattering of the Vessels" of the Sephirot in the "World of Tohu (Chaos)". The vessels of the Sephirot broke and fell down through the spiritual Worlds until they were embedded in our physical realm as "sparks of holiness" (Nitzutzot). The reason in Lurianic Kabbalah that almost all Mitzvot involve physical action, is that through their performance, they elevate each particular Spark of holiness associated with that commandment. Once all the Sparks are redeemed to their spiritual source, the Messianic Era begins. This metaphysical theology gives cosmic significance to the life of each person, as each individual has particular tasks that only they can fulfil. Therefore, "gilgulim" assist the individual soul in this cosmic plan. This also explains the Kabbalistic reason why the future eschatological Utopia will be in this World, as only in the lowest, Physical realm is the purpose of Creation fulfilled.

Spiritual dimension of all Creations.

In Kabbalah, from its initial Medieval form onwards, Creation is described as a descending Chain of spiritual Worlds of cause and effect. The new 16th-century Kabbalistic paradigm of Isaac Luria extends the meaning of this with the concept of the holy sparks. Creation is a continuous process of Divine vitality. All physical and spiritual Creations only continue to exist due to the immanent Divine Ohr ("Light"), from God's Will to create, that they constantly receive. This immanent flow forms the spark of holiness in any Created form. This teaches that the true essence of anything is only its Divine spark within, that gives it continual existence. If the light were to be withdrawn, the creation would cease to exist. This complete dependence on Divinity is hidden in this lowest physical realm, but the souls and angels of successively higher spiritual realms are nullified to the Divine Unity, in successively higher degrees. This explains the statement of Isaac Luria that even stones possess a subtle form of soul. With the focus in Lurianic Kabbalah on Cosmic Tikkun rectification, accordingly every leaf also possesses a soul that "came into this world to receive a rectification".

Above-conscious root of Gilgul.

16th-century Lurianic doctrine was the first time that Kabbalah focused on gilgul, because it forms the microcosmic parallel to the Cosmic Divine rectification taught by Luria. In Medieval Kabbalah of the Zohar, which received its full rational synthesis in 16th-century Cordoveran Kabbalah, immediately before the new teachings of Luria, Gilgul was not the focus as intellectual categorisation was sought. Lurianic Kabbalah, accordingly, while also fully systemised in rational articulation, nonetheless focuses on Divine soul levels above intellect. The central doctrine of Luria is the Tzimtzum (Divine "Withdrawal") that paradoxically transcends human logic. The Tikkun rectification of the Tzimtzum, involving the "birur" (elevation) of the sparks of Creation, and their soul parallel of Gilgul, similarly are rooted in Divine levels above intellect. In the foundational Kabbalistic structure of the 10 Sephirot (emanations), Keter (Divine Will) transcends the intellectual Sephirot, and is the origin of All.  The Lurianic idea that all physical and spiritual Creations possess their particular bodily "soul", explains the notion that gilgul can involve a person's soul occasionally being exiled into lower creatures, plants or even stones.

Five levels of the soul.

In Jewish mysticism the human soul has five levels that relate to different levels of the Sephirot (Divine emanations). Based on an ancient Midrashic source, Kabbalah (followed also in Hasidic interpretation of Kabbalah) gives names for these five levels. Their corresponding Sephirot have both outer spiritual functions (vessels) and inner dimensions (lights), that relate to outer manifestations of the human soul, and their inner psychological "soul powers". The five levels of the human soul in ascending order: The most basic component of the soul, the nefesh, is always part of the "gilgul" process, as it must leave at the cessation of blood production (a stage of death). It moves to another body, where life has begun. There are four other soul components and different nations of the world possess different forms of souls with different purposes.

Other processes of transmigration.

"Gilgul" is contrasted with the other processes in Kabbalah of Ibbur - the attachment of a second soul to an individual, and Dybuk - a malicious possessing spirit believed to be the dislocated soul of a dead person.

In Hasidism.

Internalisation of Kabbalistic structures in dveikut.

Lurianic Kabbalah focuses on the process of "gilgulim", as it forms the microcosmic parallel to macrocosmic rectification of Creation. In the elite circles of Kabbalistic scholars, it becomes beneficial to helping achieve rectification for a person to identify their particular spiritual "gilgulim".  18th-century Hasidism sought to democratise and popularise the Jewish mystical tradition, so that the common folk could be invigorated by Judaism's inner dimensions. It sought the internalisation of abstract Kabbalistic metaphysics into personal perception and fervour (dveikus), by relating the structures of Kabbalah to their inner psychological relevance in man. Because "gilgul" forms part of the elaborate, abstract structure of the processes of redemption in Kabbalah, it was therefore sidelined in Hasidic Judaism. Hasidism believed in the Kabbalah and "gilgul" as authoritative, but left aside the focus in Jewish worship and meditation on the structures, meditations and metaphysical processes, to look to the inner Godliness within everything. Hasidic panentheism devotes itself to dveikus (attachment) to the Divine Omnipresence. In this inner path, identification of one's past "gilgulim" becomes external, and a diversion from inner "Bittul" (self nullification). To identify one's particular spiritual tasks could introduce a refined level of egotism, while acting purely from dveikus to God would be a higher, essential soulful Jewish worship. The Hasidic figure of the tzadik (Hasidic Rebbe), to which the followers would flock, was believed to know the particular past "gilgulim" of each person who came to them, through their semi-prophetic abilities, and the future destiny of each person. However, in Hasidic thought, they would not directly reveal this information in private consultation, as for the follower to know the tasks would introduce self-centredness, and Divine "help from Above". Through its Divine Service, Hasidism sought to make Divinity revealed "from Below" to fulfil the Ultimate purpose of Creation. Nonetheless, the Tzadik would give assistance and special advice that would both help the follower to achieve their tasks, yet also preserve the full soulfulness "from Below" of the common person's Divine service.

Kabbalistic descent and ascent in history.

Ascending stages in the history of Jewish mysticism.

In the history of Jewish mysticism, this Hasidic approach to gilgul corresponds to the third of three successive stages of perception and relation to Divinity. This is based on the three ascending categories of existence taught by the Baal Shem Tov: Worlds ("Olamot"-External spiritual vessel forms), Souls ("Neshamot"-Internal spiritual lights), Divinity ("Elokut"-Essential Godliness).

Descent of the Generations in Halachic scholarship.

Traditional Judaism views latter generations to be spiritually inferior and lower than former generations. This belief, called Yeridat ha-dorot ("Descent of the generations"), shapes the development of traditional Jewish thought. In Talmudic commentary and Halachah it means that latter authorities in the Eras of Rabbinic Judaism generally do not disagree with authorities from a previous era. The basis of this is two-fold. In the historical chain of transmission of Judaism from generation to generation, a latter generation is further removed from the original Revelation of the Torah on Mount Sinai. The Halachic authorities of a subsequent generation would avoid disagreeing with the preceding Halachic authorities, since to reach them, the chain of Torah transmission is longer and more vulnerable to mistaken recollection. This applies until the Oral Torah was written down in the Talmud, where the Amoraim Sages of the Gemara commentary do not disagree with the earlier Tannaim Sages of the Mishna. Accordingly, the Mishnaic Pirkei Avot begins with a historical account of the chain of Oral Torah transmission from Moses, until it became written down in the Mishna. Once the Oral Torah was written down in the Talmud and its commentaries, the principle still applies for a second reason. While Halachah adapts itself to new technological innovations, the principles behind it are held to be foundational. Latter authorities are less qualified to define the fundamental parameters of Halachah.

Lower levels of souls in latter generations.

This belief in Descent of the Generations is believed in the world view of Orthodox Judaism, which traditionally based itself around Talmudic scholarship. However, the ascending levels from generation to generation in Jewish mysticism described above, an opposite pattern to the Descent of Generations, are not so well known in contemporary Orthodoxy. This is because Jewish mysticism is less understood by regular Orthodox Jews, especially outside of the mystical Hasidic Movement. Within Hasidism as well, scholarly understanding of the meaning of Hasidic philosophy in relationship to historical Kabbalah, is more restricted to certain Hasidic groups over others. The three ascending stages in Kabbalistic paradigm, listed above, do not contradict the wider belief of Descent of the Generations. Kabbalah gives its own metaphysical reason for the generational descent. In Kabbalistic theology, latter generations possess lower souls than former generations. The level of a soul in Kabbalah only refers to its revealed form, while all the souls are rooted in the same sources. A lower soul means that it's spiritual power became greatly constricted as it descended the Chain of Worlds to reach this World. Accordingly, the possessor of the soul has much more limited spiritual capabilities. In the last generations before the Messiah, the souls come from the lowest levels, even though they are gilgulim of higher souls from earlier generations. This gives the Kabbalistic interpretation of the last generations when the "Heels (footsteps) of the Messiah" are perceptible. This Talmudic phrase becomes in Kabbalah, the generations of souls that correspond in the Man-metaphor of the Sephirot to the lowest level of the "heels" of the feet. This need however not be considered a disadvantage, as in Hasidic thought, which sought inner nullification to God in dveikus, lower souls worship God with more self-sacrifice and innermost sincerity, because they act without great knowledge and fulfilment of ego. Their Divine service is able to bring the Messiah because of their devoted essential soulfulness.

Ascending mystical revelations of select Tzadikim.

In Jewish mystical thought, the descent of generations applies even more because of this metaphysical explanation. Within scholarship it applies to Halachah and Talmudic commentary because of the simple historical explanations. However, within Lurianic mysticism the opposite progressive ascendency still applies. The reason for this is because this 16th century Kabbalistic dimension of Jewish thought is innovated only by the greatest Tzadikim (saintly souls) in history, the rarest of whom are unaffected by descending generational soul levels. A "Tzadik" in early 19th century Chabad philosophy, as defined by the Tanya (c. 1814), is a truly elevated soul, unaffected by physical limitations. The rarest such Tzadikim in history, who teach new revelations in Kabbalistic thought, are considered apart from general (traditional) Tzadikim. To them is applied in Kabbalah the verse from Psalms, "The [traditional] Tzadik is the foundation of the World". 16th century Lurianic Kabbalah and 18th century Hasidic philosophy make radical statements about this believed supreme level of "Tzadik". In the Kabbalistic worldview, their new revelations in Jewish mystical thought advance the conceptual frontiers of Kabbalah from generation to generation. Therefore, while in Halachah (Jewish Law), scholarship ability decreases in each generation, in 16th century Lurianic, 18th century Hasidic, and 19th century Chabad philosophy, mystical thought is said to ascend through history. This ascent applies to Jewish mystical thought, the "Inner Torah" ("Nistar"-"Concealed") of Kabbalah, rather than the "Revealed Torah" ("Nigleh"-"Revealed") of Jewish commentaries on the Bible, Midrash, Talmud, Halachah and Medieval Jewish philosophy. The reason for this is because in Nigleh, scholarship involves discovering new and deeper interpretations of previous revealed Biblical and Rabbinic texts. In Lurianic Kabbalah, advance is made by new doctrines and individual revelations that transcend previous descriptions. "Revealed" "Nigleh" corresponds to the collaborative scholarly ascent "from Below" of human intellect up to God. "Concealed" "Nistar" corresponds to privately drawing down new revelations of Divine intellect "from Above", down into the human intellect of one individual. This is also a philosophy, as the difference between Nevuah ("Prophecy") and Kabbalah ("Received"), is that Lurianic Kabbalah becomes articulated conceptually in intellectual structures, in which allegedly lays its supremacy over prophecy.

Ascending lights, descending vessels in history.

This paradoxical dialectic is explained more generally in Hasidic thought as part of the divine cosmic plan of Kabbalistic Lights and Vessels. In each subsequent generation, the external levels of creation and this world ("vessels") descend to a lower level. This enables the difference between purity and impurity to become revealed, clarified and redeemed. At the same time, "In every generation a new, higher light descends from on High" to transform this World. This inner revelation ascends progressively to prepare for, and give a foretaste of the Messianic Era. In the future era, the constant, inner elevation of existence, the mystical purpose of creation, will be revealed, as the messianic revelations of divinity are created through the present service of God from below. In kabbalistic terminology this dialectic is also related to the "masculine waters" of "direct light" from above, and the "feminine waters" of "reflected light" from below. This explains the mystical concept in Hasidic interpretation of Kabbalah that in the messianic era, the feminine in creation will become the ascendant, and similarly the body will give life to the soul, the opposite of the present reality.  The ultimate purpose of any spiritual descent in Kabbalah is "only in order to reach a higher spiritual ascent", than the original level at the start. In the Hasidic explanation of individual Divine providence, all that occurs for every individual is a concealed part of this ultimate ascent. In its inner interpretation, the descent, such as a spiritual fall, is itself the concealed beginning of the true divine ascent. According to this Hasidic explanation, sin is an opportunity for mystical dveikus (fervour) in Teshuvah (Return to God). This expression of divine compassion excludes any misinterpretation of Jewish reincarnation as a fatalistic process of reward and punishment.

Identification of Gilgulim of historical figures.

Outline of Jewish genealogy of nations.

Traditional Judaism describes Abraham as the first Jew. With his son Isaac, and grandson Jacob, they are described as the "Fathers" of the Jewish people, and their wives, Sarah, Rebecca, Rachel and Leah are the "Mothers". These terms take on Kabbalistic meanings by being associated with some of the different Sephirot (Divine emanations). It was Moses, in traditional Judaism, who later received the teachings of Judaism at Mount Sinai, embodied in the Torah and 613 mitzvot. The other "Nations of the World", counted as 70 roots from Noah, are given the Seven Laws of Noah for spiritual redemption, and do not need to convert to Judaism, in Jewish thought, to fulfil the eschatological purpose of Creation, or private salvation.

See also.

In Judaism: For comparison with other religions:

Gilgul/Gilgul neshamot/Gilgulei Ha Neshamot (Heb., Plural: "Gilgulim") is a concept of reincarnation in Kabbalistic esoteric mysticism. In Hebrew, the word "gilgul" means "cycle" or "wheel" and "neshamot" is the plural for "souls." Souls are seen to cycle through lives or incarnations, being attached to different human bodies over time. Which body they associate with depends on their particular task in the physical world, spiritual levels of the bodies of predecessors and so on. The concept relates to the wider processes of history in Kabbalah, involving cosmic Tikkun (Messianic rectification), and the historical dynamic of ascending Lights and descending Vessels from generation to generation.

Le Guilgoul haNeshamot ou Guilgoulei haneshamot (héb. גלגול הנשמות, litt. « cycle des âmes »), plus communément désigné par Guilgoul, est le concept de la réincarnation, émanant des thèses kabbalistiques dans le judaïsme.


History.

Metro projects for the imperial capital.

The question of building an underground road in Saint Petersburg arose in 1820. A resident of the city, a self-taught man by the name of Torgovanov, submitted a bold project to Emperor Alexander I - involving the digging of a tunnel from the center of the city to Vasilyevsky Island. The Russian ruler rejected the project and ordered the inventor to sign a pledge "not to engage in hare-brained schemes in the future, but to exercise his efforts in matters appropriate to his estate." Other, more developed projects subsequently emerged, but they, too, received no recognition.  Many arguments were advanced against the construction of an underground road. The "city fathers" stated that the excavation works would "violate the amenities and respectability of the city"; the landlords affirmed that underground traffic would undermine the foundations of the buildings; the merchants feared that "the open excavations would interfere with normal trade"; but the most violent adversaries of the novelty, the clergy, insisted that "the underground passages running near church buildings would detract from their dignity". Thus all the projects for the construction of an underground passage in Saint Petersburg, and later in Petrograd, remained on paper.  By the end of the 19th century, certain interested parties began discussing the possibility of opening the Russian Empire's first metropolitan railway system. The press of the time praised the initial plans, while engineers privately worried about the serious lack of experience in the sort of projects required to build a metro; at the time, Saint Petersburg did not even have electrified tramways. However, due to the wish of the municipal authorities of the time to take ownership of the metro after its eventual entry into service, none of the aforementioned projects ever came to fruition.  In 1901 the engineer Vladimir Pechkovsky presented his project to build an elevated station in the middle of Nevsky Prospect, opposite the Kazan Cathedral, and to link it, via elevated and underground sections of track (above the Ekaterinsky and Obvodny canals and beneath the Zabalkansky prospect) with the Baltiysky and Varshavsky Rail Terminals. In the same year, Reshevsky, also an engineer, working at the behest of the Emperor's minister for transport, came up with two possible projects, which aimed primarily to unite all of Saint Petersburg's main railway stations with one urban interchange. An interesting development, the work upon which had been carried out for many years by railway engineer P.I. Balinsky (one of the first Russian metro engineers) involved plans to build a dedicated network of six urban lines, two of which would be radial lines with a total length of. The construction work (including the filling of low-lying areas of the city in order to avoid flooding, construction of 11 major bridges, embankments and viaducts at a height of, and the actual laying of track etc.) was projected to cost around 190 million rubles. However, in 1903 Emperor Nicholas II rejected the scheme before any work ever started.  Almost all pre-revolutionary designs featured the concept of an elevated metro system, similar to the Paris or Vienna metros, however, as was later discovered through the experience of operating open (ground-level) metro lines in St. Petersburg, such schemes would likely have resulted in a poor metro service. Unfortunately, at the time, Russian engineers did not have sufficient expertise or technical resources for the construction of deep tunnels through the bedrock located far beneath St Petersburg. In 1918 Moscow became the country's capital after the October Revolution of 1917 and the Russian Civil War (1917–1922) followed; for more than a decade plans to build a metro in St. Petersburg languished.

First phase construction, abandonment, and opening.

In 1938 the question of building a metro for St Petersburg (by then renamed to Leningrad), resurfaced at the initiative of Alexei Kosygin, Chairman of the Executive Committee of the Leningrad City Soviets of Working People's Deputies. Ivan Zubkov, an engineer who for his work was later to become a Hero of Socialist Labour was appointed the first director for the metro construction. The initial project was designed by the Moscow institute 'Metrogiprotrans', but on 21 January 1941 'Construction Directorate No 5 of the People's Commissariat' was founded as a body to specifically oversee the design and construction of the Leningrad Metro. By April 1941, 34 shafts for the initial phase of construction had been finished.  During the Second World War construction work was frozen due to severe lack of funding, manpower and equipment. At this time, many of the metro construction workers were employed in the construction and repair of railheads and other objects vital to the besieged city. Zubkov died in 1944, having never seen the opening of the metro.

The initial post-war era.

In 1946 "Lenmetroproyekt" was created, under the leadership of M A Samodurov, to finish the construction of the metro first phase. A new version of the metro project, devised by specialists, identified two new solutions to the problems to be encountered during the metro construction. Firstly, stations were to be built at a level slightly raised above that of normal track so as to prevent drainage directly into them, whilst the average tunnel width was to be reduced from the standard of the Moscow Metro to.  On 3 September 1947 construction began again in the Leningrad subway, and in December 1954, the Council of Ministers of the USSR ordered the establishment of the state transport organization "Leningradsky Metropoliten", to be headed by Ivan Novikov. The organisation set up its offices in the building directly above Tekhnologichesky Institut station. On 7 October 1955 the electricity was turned on in the metro,l and on 5 November 1955, the act by which the first stage of the metro was put into operation, was signed. Ten years after the end of the war, at the beginning of the post-Stalin Khrushchev Thaw, the city finally got an underground transport network. The subway grand opening was held on 15 November 1955, with the first seven stations (the eighth one, Pushkinskaya opened a few months later) being put into public use. These stations later became part of the Kirovsko-Vyborgskaya Line, connecting the Moscow Rail Terminal in the city centre with the Kirovsky industrial zone in the southwest. Subsequent development included lines under the Neva River in 1958, and the construction of the Vyborgsky Radius in the mid-1970s to reach the new housing developments in the north. In 1978, the line was extended past the city limits into the Leningrad Oblast. 1,023 governmental awards were made to participants of the construction of the metro first stage.

Further development.

The first expansion of the metro took place in 1958, when the first line (later to become the Kirovsko-Vyborgskaya Line) was extended beneath the Neva river to the Finlyandsky Rail Terminal. Later this same line was extended when the Vyborgsky radius, constructed in the 1970s, brought the metro to new residential areas constructed in the north-east of the city, and by 1978, those further out, in the nearby Leningrad Oblast. The metro was expanded to the south-west, with the construction of the Kirovsky radius, in 1977.  Construction of the second, Moskovsko-Petrogradskaya line began almost immediately after the initial opening of the metro. Just six years later, in 1961, the section from Tekhnologichesky Institut to Park Pobedy, along Moskovsky Prospect to the southern areas of the city, was opened. In 1963 the line was extended north to the station Petrogradskaya station; in the process making Tekhnologichesky Institut the USSR's first cross-platform interchange station. Further extension of the line was undertaken to the south in the early 1970s, and in the 1980s to the north, with the final station Parnas being opened, following numerous delays, in 2006. The third Nevsko-Vasileostrovskaya Line was first opened in 1967 and eventually linked Vasilievsky Island, the city centre, and the industrial zones on the southeastern bank of the Neva in a series of extensions (1970, 1979, 1981 and 1984). The fourth line, Pravoberezhnaya, was opened in 1985 to serve the new residential districts on the right bank of the Neva before reaching the city centre in 1991 and continuing to the northwest in the late 1990s. It was in this period that the opening of the metro's fifth (Frunzensko-Primorskaya) line was planned, however, it was only in 2008, with the opening of Volkovskaya and Zvenigorodskaya stations, that this took place. On 7 March 2009, when the fourth line was expanded with the addition of Spasskaya station, the fifth line finally (as dictated in earlier projects) began to directly serve both the Primorsky and Frunzensky districts of Saint Petersburg.  By the time of the USSR's collapse, the Leningrad Metro comprised 54 stations and of track. Up until this period, it was officially known as the 'V.I. Lenin Leningrad Metro of the Order of Lenin' (Леининградский Метрополитен Ордена Ленина имени В.И.Ленина).

The modern, post-Soviet period.

At the beginning of 1992 construction work was being carried out at 14 stations, or objects relating to them. These were six stations of the Primorsky radius (Admiralteyskaya, Sportivnaya, Chkalovskaya, Krestovsky Ostrov, Staraya Derevnya, and Komendantsky Prospekt), two stations on the fourth line (Spasskaya and transfer tunnels to Sadovaya station), Parnas and the 'Vyborg' depot on line 2, and five stations of the Frunzensky radius (Zvenigorodskaya, Obvodny Kanal, Volkovskaya, Bukharestskaya, and Mezhdunarodnaya). Thus, it was believed, considering the average time of construction of a metro station in Saint Petersburg being equal to 5.6 years, that, with sufficient funding, all the works mentioned above would be completed by no later than 1997; a record in the history of the construction of the St. Petersburg metro. This however, was not achieved, and the plans were only completed in late 2012.  In 1994 it was planned, over 10 years, to massively extend the metro and almost "double" its size, building three new lines and 61 new stations. However, in reality, over this period until 2004, just 6 stations were opened. At this point the metro considered funding construction through a system of individual stage and station sponsorship. Saint Petersburg's unforgiving geology has frequently hampered attempts by Metro builders. The most notable case took place on the Kirovsko-Vyborgskaya Line. While constructing the line in the 1970s, the tunnelers entered an underground cavity of the Neva River. They managed to complete the tunnel, but in 1995 the tunnel had to be closed and a section of it between Lesnaya and Ploschad Muzhestva flooded. For more than nine years, the northern segment of the line was physically cut off from the rest of the system. A new set of tunnels was built and in June 2004 normal service was restored.

Lines.

Line 1 (Kirovsko-Vyborgskaya).

Line 1 (also known as the Kirovsko-Vyborgskaya Line) is the oldest line of the metro, opened in 1955. The original stations are very beautiful and elaborately decorated, especially Avtovo and Narvskaya. The line connects four out of five Saint Petersburg's main railway stations. In 1995, a flooding occurred in a tunnel between Lesnaya and Ploschad Muzhestva stations and, for nine years, the line was separated into two independent segments (the gap was connected by a shuttle bus route). The line contains three of the six shallow stations that are present in the metro.  The line cuts Saint Petersburg centre on a northeast-southwest axis. In the south its alignment follows the shore of the Gulf of Finland. In the north it extends outside the city limits into the Leningrad oblast (it is the only line to stretch beyond the city boundary). The Kirovsko-Vyborgskaya Line generally coloured red on Metro maps.

Line 2 (Moskovsko-Petrogradskaya).

The Moskovsko-Petrogradskaya Line is the second oldest line of the metro, opened in 1961. It featured the first cross-platform transfer in the USSR. It was also the first metro line in Saint Petersburg to feature a unique platform type that soon became dubbed as "Horizontal Lift". The line cuts Saint Petersburg on a north-south and is generally coloured blue on Metro maps. In 2006, as an extension was opened, it became the longest line on the system.

Line 3 (Nevsko-Vasileostrovskaya).

The Nevsko-Vasileostrovskaya Line is a line of the metro, opened in 1967. Since 1994, it has been officially designated as Line 3. It stands out among St. Petersburg metro lines for two reasons — its stations are almost exclusively of "Horizontal Lift" type and it has the longest inter-station tunnels in the entire system. Metro officials originally intended to add stations in-between the existing ones, but those plans were later abandoned.  The line cuts Saint Petersburg centre on an east-west axis and then turns southeast following the left bank of the Neva River. It is generally coloured green on Metro maps.

Line 4 (Pravoberezhnaya).

The Pravoberezhnaya Line was opened in 1985, it is the shortest line in the system with the stations featuring a modern design. Since 1994, it has been officially designated "Line 4", but the original name is still often used in informal context.  The line originally opened to provide access from the centre for the new residential areas in the eastern part of city, along the right bank of the Neva River. However, delays in the construction of the future Frunzensko-Primorskaya Line (Line 5), compelled the metro officials to temporarily link the already completed northern part of the Line 5 (starting from Sadovaya) to Pravoberezhnaya Line, as they felt that it was better to have a single connected line rather than two unconnected ones. From that point on, the line expanded northward, as per original plans of Line 5 expansion.  On 7 March 2009 Spasskaya station was completed, creating the city's first three-way transfer and it officially became the new terminal for Line 4. As per the original plan, all Line 4 stations north of Dostoyevskaya were absorbed into the recently opened Frunzensko-Primorskaya Line.

Line 5 (Frunzensko-Primorskaya).

The Frunzensko-Primorskaya Line connects the city's historical centre to the northwestern and southern neighbourhoods. The line is planned to be expanded to the north.  The line originally opened in December 2008. It contained only two stations until 7 March 2009, when the Line 4 (Pravoberezhnaya Line) segment between Komendantsky Prospekt and Sadovaya stations became a part of the new line.

Line 6 (Krasnosel'sko-Kalininskaya).

The Krasnosel'sko-Kalininskaya Line will go from the south-west of Saint Petersburg, through the city centre, to the north-east of the city. The first stretch, which consists of six stations, is under construction, and should be opened before 2020. The first six stations will be: Yugo-Zapadnaya, Putilovskaya, Bronevaya, Zastavskaya, Borovaya and Obvodny Kanal 2.

Stations.

Some of the features of the Saint Petersburg Metro make it stand out amongst others, even those in the former USSR. It is customary to have stations in the centre of a city built very deep, not only to minimise disruption, but also, because of the Cold War threat, they were built to double as bomb shelters, and many old stations do feature provisions such as blast doors and air filters. In most cities, the lines become shallow or even begin to run above ground as they reach the city's outer residential districts. However, this is not the case in Saint Petersburg. The difficult geology means that all but 9 stations are at a deep level. The design and architecture went through numerous phases. The original stations were predominantly of the pylon type, of which there are 15 stations. Also popular was the column layout, and there are 16 such stations in the system.  The first stage is exquisitely decorated in the Stalinist Architecture style, but from 1958, Nikita Khrushchev's struggle with decorative extras restricted the vivid decorations to simple aesthetic themes. During this time a new design called "horizontal lift" became widespread, and 10 stations were built with this layout. The horizontal lift design is a variation of a station with platform screen doors, and has not been found elsewhere outside Saint Petersburg. However, because the design became unpopular with passengers, and for technical reasons, no stations featuring this design were built between 1972 and 2018. From the mid-1970s, a new open "single-vault" design was developed by local engineers and became very popular, not only in Saint Petersburg, but some other cities as well. Known technically as "Leningradky Odnosvod", it remains the most popular of all and there are 16 such stations in the city.  The remaining stations are located virtually on the edge of the city, and one, Devyatkino, is territorially in Leningrad Oblast, far away from the harsh underground geology that forms the Neva Delta. The six shallow column stations are located in the southern and northwestern sections of the city, and the first three are found on the Kirovsko-Vyborgskaya Line. The first one, Avtovo, is considered to be one of the most beautiful stations in the world and was opened as part of the first stage in 1955, while the other two were built in the late 1970s as typical Moscow-style pillar trispan stations. There are two shallow-column stations on the Nevsko-Vasileostrovskaya Line: Novokrestovskaya and Begovaya. Both of these stations, which use a modified version of the horizontal lift design, were opened in May 2018 as part of the line's extension to the northwestern section of the city. A sixth shallow-column station, Dunayskaya, opened in October 2019 as part of the Frunzensko-Primorskaya Line's southern extension. In addition, there are four termini stations that are on the surface and are located near the lines' connection with the train depots. The city's northern climate means that even here all of the station space is inside an enclosed structure.

Plans.

The Metro has a very large expansion plan for the next half century. The Pravoberezhnaya Line was split in early 2009, and the new fifth line (Frunzensko-Primorskaya) took the northern (Primorsky) radius away from Pravoberezhnaya and opened with a new section (Frunzensky) to the south. The Pravoberezhnaya line will extend to the west, and then north to Lakhta, and then to Yuntolovo. The two stations, Bukharestskaya and Mezhdunarodnaya of the Frunzensko-Primorskaya line, opened in December 2012, will be followed by another three heading southward - Prospekt Slavy, Dunayskaya and Shushary. These should be open in 2018. Three new lines, Krasnoselsko-Kalininskaya, Admiralteysko-Okhtinskaya and Koltsevaya, will be opened. The first six stations of the Krasnoselsko-Kalininskaya line are already under construction, and should be open by 2020. The Admiralteysko-Okhtinskaya line should appear before 2025. The Koltsevaya line will be opened after 2025.  Back in 2012, the official website of the Saint Petersburg metro claimed the opening of 54 new stations, 5 new depots and of new lines. Delays due to the difficult geology of the city's underground and to the insufficient funding have cut down these plans, as of 2014 (2 new stations later), to 17 new stations and one new depot until 2025.  At the same time, there are several short and mid-term projects on station upgrades, including escalator replacements and lighting upgrades.

Operation.

The Metro is managed by the state municipal company "Sankt-Peterburgsky Metropoliten" ("Saint Petersburg Metropolitan", ) that was privatised from the Ministry of Rail Services. The Metro was renamed to coincide with the city's name change in the early 1990s. The company employs several thousand men and women in station and track management as well as rolling stock operation and maintenance.  The Metro is financed by the city of Saint Petersburg, from passenger fares, and from advertisement space at the stations and on the trains. Metro construction is undertaken by the subsidiary "Lenmetrostroy" () that is financed by the Metro as well as directly by the Ministry of Transportation.

Rolling stock.

The rolling stock of the metro is provided by five depots with a total of 1403 cars forming 188 trains. Most of the models are the Metrowagonmash 81-717/714 that are very common in all ex-Soviet cities. In addition there are older E and Em type trains on the Kirovsko-Vyborgskaya Line and newer 81-540/541 (built by Škoda Transportation unit Vagonmash) on the Pravoberezhnaya and Fruzenskaya-Primorskaya Line. In addition, the Metro has also received 81-722 and 81-724 cars from Metrowagonmash, which are custom models specifically for Saint Petersburg. Both these and the Skoda cars are equipped with sliding doors that go in to pockets rather than the plug doors now being used elsewhere. This is due to the fact that several stations on the system have platform doors that do not permit sufficient clearance for the plug ones. Transmashholding unveiled a new prototype train for the St Petersburg Metro in June 2019, no orders have been placed as of November 23rd 2019.

Security.

The Metro was originally built as a system that could offer shelter in case of a nuclear attack. Every station is equipped with CCTV surveillance following recent terrorist threats. Until the summer of 2009, all photography and video filming in the Metro required a written permit. However, because of a legal challenge by an amateur photographer, after 24 August 2009, photography without a flash can be done without a permit.

Incidents.

Terrorist bombings.

Approximately fourteen people died and over 50 sustained injuries from an explosion 3 April 2017 on a train between Sennaya Ploshchad and Tekhnologicheski Institut stations, on the Line 2. The explosion occurred at 2:20 pm, local time. Seven individuals were confirmed DOA, while others were rushed to hospital. Russian President Vladimir Putin's hometown is Saint Petersburg, and he was in the city visiting when the attack occurred. He issued condolence statements to the victims' families immediately after the blast.  Russia's National Anti-Terrorism Committee also on 3 April defused an improvised explosive device at Ploshchad Vosstaniya station, on the Line 1.

The Saint Petersburg Metro () is a rapid transit system in Saint Petersburg and Leningrad Oblast, Russia. It has been open since 15 November 1955.

Le métro de Saint-Pétersbourg () est le système de transport en commun de la ville Saint-Pétersbourg en Russie. Ce métro présente des caractéristiques typiques des métros de l'ancienne Union soviétique : décoration, aspect monumental. À cause de la géologie du sous-sol de la ville, le métro de Saint-Pétersbourg circule à très grande profondeur (80 mètres). Le métro transporte quotidiennement 3,43 millions de passagers.


Background.

In late 1805, First Lord of the Admiralty Lord Barham withdrew the Royal Navy blockade of the French Atlantic ports following the Trafalgar Campaign, in which the French Navy had lost 14 ships of the line. Barham believed that the French, having suffered such heavy losses, would be unable and unwilling to launch a major offensive in the Atlantic until after the winter. However, he had miscalculated the strength of the fleet at Brest, the principal French Atlantic seaport. The Brest fleet had not been engaged in the 1805 campaign and was therefore intact.  Taking advantage of the withdrawal of the British blockade, Emperor Napoleon ordered two squadrons to put to sea with orders to raid the British trade routes that crossed the Atlantic. These forces were to inflict as much economic damage to Britain as possible without engaging an equivalent British naval squadron and risking defeat and capture. The cruise was expected to last as long as 14 months, sustained by captured food supplies from British merchant ships. Sailing unopposed on 13 December 1805, the squadrons separated two days later in pursuit of British merchant convoys, one squadron steering for the South Atlantic under Contre-Admiral Jean-Baptiste Willaumez and the other, under Vice-Admiral Corentin-Urbain Leissègues, sailing for the Caribbean. The Admiralty in London did not discover that the French had sailed until 24 December, and the two squadrons they prepared in pursuit, under Rear-Admiral Sir Richard Strachan and Rear-Admiral Sir John Borlase Warren, did not sail until January 1806, by which time the French had disappeared into the Atlantic.  There was however one British squadron that had maintained contact with the French: since the Battle of Trafalgar in October 1805, the Admiralty had stationed a squadron under Vice-Admiral Sir John Thomas Duckworth off Cadiz to watch the remnants of the combined fleet. In November 1805, reports reached Duckworth of a French squadron operating against British convoys off the Savage Islands between Madeira and the Canary Islands. This squadron, which belonged to Contre-Admiral Zacharie Allemand, had left France in July 1805. Immediately sailing to investigate, Duckworth abandoned Cadiz, leaving just two frigates to watch the Allied fleet at anchor. Passing the Savage and Canary Islands, Duckworth continued to the Cape Verde Islands before conceding that the French had escaped him and turning northwards again. Allemand was already far to the north. He eventually returned to France without incident on 23 December.

Duckworth's cruise.

During his return journey to Cadiz, on 23 December Duckworth encountered under Captain Charles Brisbane escorting a small group of merchant ships. Leissègues had intercepted, chased and dispersed Brisbane's convoy in the Bay of Biscay on 15 December, Brisbane retaining only the largest merchant ships to help cover the flight of the smaller vessels. Once he had escaped Leissègues' pursuit, Brisbane sailed in search of support at Cadiz, continuing southwards after realizing that Duckworth was not at his appointed station. Immediately setting a course that he believed would intercept Leissègues, Duckworth turned to the northwest and on 25 December discovered an enemy squadron approximately northwest of the Canary Islands. Duckworth ordered his squadron to pursue, the chase lasting throughout the day and continuing into 26 December, by which time it had become clear that his quarry was not Allemand. In fact, Duckworth had discovered Willaumez's squadron. However, the French admiral ordered his ships to run before Duckworth rather than give battle. By 13:00 on 26 December, it seemed certain that the British flagship,, would outstrip the rearmost French ship, when Duckworth suddenly called off the pursuit. He later claimed that he was concerned that the leading ships of his squadron would be overwhelmed by the concentrated French squadron before the stragglers, some of which were more than behind "Superb", could join the battle.  As Willaumez escaped into the South Atlantic, Duckworth ordered his squadron to sail for Barbados to resupply before making the long journey back to Cadiz. When he arrived on 12 January 1806, he ordered the frigate to St. Kitts to arrange the required water supplies, and moved the squadron to an anchorage off Basseterre on 19 January. There two ships of the Leeward Islands squadron, and, joined him. "Northumberland" was the flagship of Rear-Admiral Alexander Cochrane, commander of the station. Cochrane's arrival raised the number of admirals in the squadron to three, as Duckworth's second in command was Rear-Admiral Thomas Louis in. Leissègues was also "en route" to the Caribbean, winter storms off the Azores having delayed him, separated "Alexandre" and "Brave" and inflicted damage on "Jupiter" and "Diomède". Arriving at the French-held city of Santo Domingo on the island of Hispaniola on 20 January, Leissègues disembarked over 1,000 soldiers as reinforcements for the garrison, and made hasty repairs as he awaited the arrival of his missing ships, which appeared on 29 January. During his time in the harbour, Leissègues moved ashore and gave orders for the ships to be recaulked following their Atlantic voyage, a difficult and time-consuming process.  On 1 February the small sloop arrived at Basseterre with information that three French ships of the line had been sighted off Santo Domingo. Duckworth gave orders for the fleet to sail immediately. On 3 February the brig joined him at St. Thomas and on 5 February the frigate under Captain Adam Mackenzie joined near the Mona Passage. Mackenzie was accompanied by a Danish schooner that had sailed from Santo Domingo a few days before, and whose crew were able to provide a detailed account of the French squadron's composition. Before the schooner had sailed, a number of French officers had commented on the risk involved in allowing the vessel to leave port, but the admiral had refused their demands that he burn the Danish ship. Duckworth was now confident that he outnumbered and outgunned Leissègues. During the night of 5 February the British squadron slowly approached Santo Domingo, "Acasta" and "Magicienne" scouting ahead of the main fleet.

Battle.

Duckworth's attack.

At 06:00 on 6 February Duckworth's scouts sighted the French, observing two frigates, five ships of the line and one large merchant ship anchored in line at the entrance to Santo Domingo. Leissègues had reportedly issued orders for the squadron to sail for Jamaica, even though several of the French ships were not yet ready for sea, and two frigates were already under sail when the British arrived. Leissègues was not aboard "Impérial"; he and a number of his officers were still conducting their business in the town and were therefore forced to join the squadron in small boats, which delayed the squadron. Several officers, possibly including Leissègues, did not reach their ships until after the engagement had begun. Recognising that his enemy was in a vulnerable position, Duckworth raised all sail in an effort to close with the French. Leissègues too recognised the danger his ships were in and ordered them to raise anchor and then to sail westwards along the coast in the direction of Nizao. Maintaining close formation, the French formed a line of battle, Captain Pierre-Elie Garreau in "Alexandre" leading, with "Impérial", "Diomède", "Jupiter" and "Brave" following. The frigates and corvette took a position between the battle line and the shore. Duckworth was concerned that there might be other French forces to the west. He therefore angled his line of attack to pass across the front of the French line and signaled to his squadron to direct their fire at the front three ships: "Alexandre", "Impérial" and "Diomède". At 08:00 Duckworth's ships divided into two divisions, a westerly line to windward under Duckworth with "Superb", "Northumberland", and, and an eastern line under Louis with "Canopus", and "Atlas". The British frigates were gathered in formation to the west of the British lines, awaiting orders to assist if required. Over the next two hours the British slowly closed with the French squadron, the British divisions breaking up as the faster ships outpaced the slower. Louis' squadron fell behind Duckworth's, while "Agamemnon" dropped behind the other three vessels in her division, which otherwise remained in a tight formation. A slight shift in the wind allowed Leissègues to adjust his direction to the southwest, but the close presence of the land restricted French movements and at 10:10 "Superb" was able to open fire on "Alexandre". With the British flagship engaged with the leading French vessel, "Northumberland" opened fire on the next in line, Leissègues' flagship "Impérial". The French ship carried 120 guns to "Northumberland"<nowiki>'</nowiki>s 74, but Cochrane engaged closely, rapidly supported by "Spencer", which opened fire on "Impérial" and "Diomède" simultaneously. For 15 minutes the British continued to close, both squadrons sailing westwards along the coast with the wind. At 10:25, the damaged "Alexandre" suddenly swung out of the line in an attempt to drive between "Spencer" and "Northumberland" and rake them both. Captain Robert Stopford on "Spencer" responded rapidly, turning across "Alexandre"<nowiki>'</nowiki>s bow and raking her, before pulling along the opposite side of Garreau's "Alexandre" and opening fire from close range. In the smoke and confusion neither "Superb" nor "Northumberland" noticed "Spencer"<nowiki>'</nowiki>s move; both fired several shots into "Spencer" before they realized their mistake. With "Spencer" and "Alexandre" out of the way, "Impérial" was able to engage both of the leading British ships, threatening to overwhelm them. Cochrane moved to defend the flagship by pulling "Northumberland" between "Impérial" and "Superb", suffering terrible damage but preserving Duckworth's ship intact. "Impérial"<nowiki>'</nowiki>s fire was so heavy that several shot passed straight through "Northumberland" into "Superb".

Destruction of the French rear.

As the combat raged at the head of the line, the remainder of both squadrons strained to join the battle. The British eastern division under Louis reached the battling "Alexandre" and "Spencer" at 10:35, the two ships locked together to the south of the main engagement. As they passed, "Canopus", "Donegal" and "Atlas" all raked the French ship, bringing down all her masts and leaving her in a crippled state. "Canopus" then steered directly towards the battle around "Impérial", as "Donegal" and "Atlas" turned northwest to intercept "Brave" and "Jupiter" respectively. At 11:00, "Spencer" followed "Canopus" while "Alexandre"<nowiki>'</nowiki>s crew were preoccupied with extinguishing a fire that had broken out on board. "Alexandre" was so badly damaged that she was unable to either escape or continue the action; she formally surrendered ten minutes later.  Captain Pulteney Malcolm on "Donegal" attacked "Brave" directly, firing his starboard guns and then crossing "Brave"<nowiki>'</nowiki>s stern, inflicting severe damage with a raking broadside, before pulling alongside again and engaging from close range. Badly damaged, "Brave" surrendered. Malcolm then ordered Captain Richard Dunn in "Acasta" to take possession as "Donegal" moved forward to engage "Jupiter". With "Donegal" alongside "Jupiter", Captain Samuel Pym in "Atlas" abandoned his brief engagement with the French ship and steered for the melee surrounding the increasingly isolated "Impérial". Taking advantage of his ship's superior speed, Malcolm pulled ahead of "Jupiter" and then rammed her bow, securing the ships together to prevent the French vessel from escaping. Recognising that further resistance was hopeless, Captain Gaspard Laignel surrendered immediately. Malcolm then sent 100 men on board as a prize crew and attached a towline to the French ship, just as the trailing "Agamemnon" finally reached the battle.

Leissègues drives ashore.

Under the shroud of heavy smoke that confused the positions and identities of the ships at the head of the line, manoeuvering became hazardous: "Atlas" fired two broadsides into "Impérial" as she arrived and then raked the French flagship before her tiller jammed just as "Diomède" loomed out the smoke. Receiving a heavy broadside from the French ship, "Atlas" subsequently collided with "Canopus" as she too appeared immediately ahead, tearing off her bowsprit in the collision. Turning back into the battle, "Atlas" engaged "Diomède" at close range as the rest of the British squadron concentrated their fire on the beleaguered "Impérial", with the exception of the damaged "Northumberland", which was drifting out of the line.  With his main and mizzen masts collapsed and escape impossible, Leissègues turned his ship towards the shore at 11:30, outdistancing the fire from the drifting "Northumberland" and leaving "Superb" behind, Duckworth reluctant to risk his ship in the shallow coastal shoals. "Canopus" maintained the pressure, pursuing the French flagship until it was clear at 11:40 that "Impérial" was hard aground on a coral reef, less than a mile from the beach. "Diomède", under attack by "Atlas" and the recently returned "Spencer", followed "Impérial" ashore. As they struck the reef, both French ships lost their remaining masts and suffered severe damage to their hulls. Their crews then gathered on deck and made preparations to abandon ship as the British squadron pulled back out of range of fire from the shore. During the engagement the French frigates and corvette had all slipped between the battling squadrons and the shoreline and escaped to the westwards. The British frigates were too preoccupied with boarding and towing prizes to initiate a chase.

Destruction of "Impérial" and "Diomède".

As Duckworth gathered his squadron, "Northumberland"<nowiki>'</nowiki>s mainmast collapsed across the deck, causing severe damage to the ship's fittings. Although Cochrane's flagship was the most severely damaged of the squadron, all had suffered to a degree: "Superb"<nowiki>'</nowiki>s men counted 60 shot holes while "Atlas" was out of control and "Donegal" had lost one of her topmasts. Casualties were also distributed throughout the fleet, with "Northumberland" and "Spencer" suffering the worst and "Atlas" the least except for the barely engaged "Agamemnon". Total losses were 74 killed and 264 wounded and several ships were damaged, but Duckworth was rapidly able to effect repairs as his ships remained on station to observe the situation ashore.  "Impérial" and "Diomède" had both run aground between Nizao and Point Catalan, their hulls broadside to the beach and their bottoms stove in by the reefs that lay offshore. Using the remaining ship's boats and with assistance from the shore, the wounded and survivors were ferried to the beach. These operations continued uninterrupted until 8 February, when Duckworth sent boats from "Acasta" and "Magicienne" to the wrecks. Boarding unopposed, the boat parties removed the remaining French crewmen as prisoners and set both ships on fire to deny their potential use to the French, although Leissègues had in fact already issued orders for them to be burnt once the last men had been evacuated. Her captain, Jean-Baptiste Henry, was among the 150 prisoners the British took from "Diomède". By contrast, the British found only six men still aboard "Impérial", none of them officers. French casualties in the engagement were very heavy, with over 500 men estimated to have been killed or wounded on "Impérial" alone and over 1,000 additional casualties shared among the rest of the fleet. "Jupiter" had not been severely damaged in the engagement and "Brave", although damaged in the hull, was in a sailing condition. Both ships had surrendered early in the engagement after losing their captains killed or wounded, in the initial exchanges. "Alexandre", by contrast, was a shattered wreck. Her British prize crew only just prevented the gaping holes smashed in her hull from sinking her.  Duckworth remained at anchor off Santo Domingo for several more days until his entire squadron and their prizes were ready for the voyage to Jamaica, sending Commander Nathaniel Day Cochrane to Britain in "Kingfisher" with the official despatches. Admiral Cochrane separated from the fleet on the day of departure and "Northumberland" and "Agamemnon" sailed for Barbados in case other French forces should appear in the Leeward Islands while the main fleet was repairing at Jamaica. Duckworth was received at Jamaica with "rapturous acknowledgments" and his prizes were refitted for the journey back to Britain. In the event, "Brave" foundered off the Azores with the loss of three men, and "Alexandre" was too badly damaged for further service, being broken up on arrival. Only "Jupiter", renamed HMS "Maida" after the recent French defeat at the battle of Maida in Italy, had any continued career in the Royal Navy. The only surviving French ships, the frigates "Comète" and "Félicité", and the corvette "Diligente" all returned to France without incident over the following months.

Aftermath.

The victory, just four months after the success at Trafalgar, was celebrated in Britain and across the Empire, particularly in the Caribbean. Mere rumours of Leissègues' presence had stifled trade and caused panic among the merchant houses of the West Indies and Duckworth's victory helped to restore confidence in commercial ocean travel once more. In Britain both the House of Commons and the House of Lords voted their thanks to the entire squadron when Duckworth's account of the action was read out, the motions led by Lord Grenville and Charles Grey, who both made expansive speeches in praise of Duckworth. Head money, a bounty on enemy servicemen killed, wounded or captured, was paid for 4,268 men, even though records showed that the French fleet carried significantly fewer men than that. Additional prize money was paid for the captured "Jupiter" and awards of money, ceremonial plate and ornate swords were made by patriotic societies and Lloyd's of London insurers. Admiral Louis was made a baronet and Cochrane a Knight Companion of the Order of the Bath, while a number of promotions were distributed among the first lieutenants. Duckworth, however, received nothing beyond his share of the general rewards. Vice-Admiral Lord Collingwood, commander in chief of the Mediterranean, was furious that Duckworth had deserted his post off Cadiz, failed to bring Willaumez to battle in December and then sailed for the West Indies to resupply rather than returning to the Spanish coast. Historians William James and William Laird Clowes both considered that if Duckworth had not defeated Leissègues he would probably have faced a court martial. Duckworth's absence forced Collingwood to divert some of his own ships to the Cadiz blockade. The force provided still proved inadequate – on 26 February a French frigate squadron broke out of the port and escaped to Rochefort. Collingwood's influence was enough to block additional rewards to Duckworth, who subsequently returned to the Mediterranean and in 1807 commanded the fleet at the ineffectual Dardanelles Operation. Over four decades later the battle was among the actions recognised by a clasp attached to the Naval General Service Medal, awarded upon application to all British participants still living in 1847.  In France, the government press misrepresented the battle. "Le Moniteur Universel" published a report purportedly written by Captain Raymond Cocault of the corvette "Diligente". The report began by inaccurately claiming that the British squadron consisted of nine ships of the line. The report concluded with the information that two British ships had been destroyed on the San Domingo coast alongside three French and that two others had been dismasted and were badly damaged. The official French report, written by Leissègues but not published in France, contradicted this version of events. Leissègues stated that Cocault, with the other smaller warships, had made all sail to the westwards at the start of the engagement and that by the time the flagship drove ashore, "Diligente" was already out of sight. Leissègues remained on Santo Domingo for some time, but had returned to Europe by the time the colony fell to a joint British and Spanish force in July 1809. He later received a regional command in the Ionian Sea and took part in the Adriatic campaign.  The Atlantic campaign continued throughout the spring and summer. Willaumez was able to avoid the British squadrons searching for him by remaining deep in the South Atlantic. However, on 13 March 1806 the British under Warren intercepted and defeated an unrelated French squadron under Contre-Admiral Charles-Alexandre Durand Linois while he was returning from the Indian Ocean. Eventually forced north in search of additional food supplies, Willaumez entered the Caribbean, where he hoped to intercept the Jamaica convoy to Britain. The disobedience of one of his own captains foiled Willaumez's plan and he ordered his squadron to its final cruising ground, off Newfoundland. On 18 August 1806, while it was deep in the Central Atlantic, a ferocious hurricane caught the squadron and scattered it. Willaumez eventually found shelter in Havana; a number of his ships reached ports in the United States, some too badly damaged to ever sail again. Only four of the 11 ships of the line that left Brest in December 1805 ever returned to France. San Domingo was the last fleet battle of the Wars to be fought in open water; the only subsequent engagement between fleets was the Battle of Basque Roads, fought in the narrow, shallow waters at the mouth of the Charente River.

The Battle of San Domingo was a naval battle of the Napoleonic Wars fought on 6 February 1806 between squadrons of French and British ships of the line off the southern coast of the French-occupied Spanish colonial Captaincy General of Santo Domingo ("San Domingo" in contemporary British English) in the Caribbean.

La bataille navale de San Domingo se déroula le au large de Santo Domingo, sur l'île d'Hispaniola, entre une escadre britannique conduite par le vice-amiral Duckworth et une plus petite escadre française conduite par le contre-amiral Leissègues.


Biography.

Throughout his reign, his foreign policy seems to have been closely linked to that of Castile. His mother was an aunt of count Sancho García of Castile, and also of the powerful count of Saldaña, García Gómez of Carrión, and she appears to have played a role in forming a bridge between the kingdom and county.  He joined his cousin Sancho in attempting to break from the submission his father had offered to Córdoba, as a result of which he had to face Almanzor. In 996 he was forced to seek peace in Córdoba. In 997 during an expedition into the land of Calatayud, García killed the governor's brother. Almanzor took revenge by beheading 50 Christians. At the Battle of Cervera in July 1000, he joined, along with count García Gómez of Saldaña, in a coalition headed by count Sancho García of Castile that was defeated by Almanzor (that count Sancho led the group is thought to reflect García's decline). Tradition names him one of the Christian leaders at the 1002 Battle of Calatañazor, which resulted in the death of Almanzor and the consequent crisis in the Caliphate of Córdoba, but there is no contemporary record of him after 1000, while his cousin Sancho Ramírez of Viguera may have been ruling in Pamplona in 1002. García was certainly dead by 1004, when his son Sancho Garcés III first appears as king.  Domestically, he granted the rule in Aragon to his brother Gonzalo, under the tutelage of his mother Urraca. A tradition reports that he freed all of the Muslim captives being held in the kingdom.

Marriage and children.

García Sánchez II was married to Jimena Fernández, daughter of Fernando Bermúdez, Count of Cea and a distinguished member of the highest ranks of the nobility of the Kingdom of León. They had the following children:

García Sánchez II (Basque: "Gartzea II.a Santxez"; died c. 1000), was King of Pamplona and Count of Aragon from 994 until his death c. 1000. He was the eldest son of Sancho II of Pamplona and Urraca Fernández and the second Pamplonese monarch to also hold the title of count of Aragon. Modern historians refer to him as "the Tremulous", though this appellation likely originally applied to his grandfather, García Sánchez I of Pamplona.

Garcia III de Navarre, dit « Le Trembleur », (né à Tudela vers 958, mort à Medinaceli en 1000). Il fut comte d'Aragon de 994 à 1000 et régna sur la Navarre de 994 à 1005. Il cherche dans un premier temps à se libérer de la domination d'Al-Andalus, que son père avait acceptée, mais après un conflit avec Almanzor, en 997, il est contraint de se rendre à Cordoue, pour demander la paix.


Structure.

The essential feature of a glycolipid is the presence of a monosaccharide or oligosaccharide bound to a lipid moiety. The most common lipids in cellular membranes are glycerolipids and sphingolipids, which have glycerol or a sphingosine backbones, respectively. Fatty acids are connected to this backbone, so that the lipid as a whole has a polar head and a non-polar tail. The lipid bilayer of the cell membrane consists of two layers of lipids, with the inner and outer surfaces of the membrane made up of the polar head groups, and the inner part of the membrane made up of the non-polar fatty acid tails.  The saccharides that are attached to the polar head groups on the outside of the cell are the ligand components of glycolipids, and are likewise polar, allowing them to be soluble in the aqueous environment surrounding the cell. The lipid and the saccharide form a glycoconjugate through a glycosidic bond, which is a covalent bond. The anomeric carbon of the sugar binds to a free hydroxyl group on the lipid backbone. The structure of these saccharides varies depending on the structure of the molecules to which they bind.

Metabolism.

Glycosyltransferases.

Enzymes called glycosyltransferases link the saccharide to the lipid molecule, and also play a role in assembling the correct oligosaccharide so that the right receptor can be activated on the cell which responds to the presence of the glycolipid on the surface of the cell. The glycolipid is assembled in the Golgi apparatus and embedded in the surface of a vesicle which is then transported to the cell membrane. The vesicle merges with the cell membrane so that the glycolipid can be presented on the cell's outside surface.

Glycoside hydrolases.

Glycoside hydrolases catalyze the breakage of glycosidic bonds. They are used to modify the oligosaccharide structure of the glycan after it has been added onto the lipid. They can also remove glycans from glycolipids to turn them back into unmodified lipids.

Defects in metabolism.

Sphingolipidoses are a group of diseases that are associated with the accumulation of sphingolipids which have not been degraded correctly, normally due to a defect in a glycoside hydrolase enzyme. Sphingolipidoses are typically inherited, and their effects depend on which enzyme is affected, and the degree of impairment. One notable example is Niemann–Pick disease which can cause pain and damage to neural networks, and is usually fatal in early infancy.

Function.

Cell–cell interactions.

The main function of glycolipids in the body is to serve as recognition sites for cell–cell interactions. The saccharide of the glycolipid will bind to a specific complementary carbohydrate or to a lectin (carbohydrate-binding protein), of a neighboring cell. The interaction of these cell surface markers is the basis of cell recognitions, and initiates cellular responses that contribute to activities such as regulation, growth, and apoptosis.

Immune responses.

An example of how glycolipids function within the body is the interaction between leukocytes and endothelial cells during inflammation. Selectins, a class of lectins found on the surface of leukocytes and endothelial cells bind to the carbohydrates attached to glycolipids to initiate the immune response. This binding causes leukocytes to leave circulation and congregate near the site of inflammation. This is the initial binding mechanism, which is followed by the expression of integrins which form stronger bonds and allow leukocytes to migrate toward the site of inflammation. Glycolipids are also responsible for other responses, notably the recognition of host cells by viruses.

Blood types.

Blood types are an example of how glycolipids on cell membranes mediate cell interactions with the surrounding environment. The four main human blood types (A, B, AB, O) are determined by the oligosaccharide attached to a specific glycolipid on the surface of red blood cells, which acts as an antigen. The unmodified antigen, called the H antigen, is the characteristic of type O, and is present on red blood cells of all blood types. Blood type A has an N-acetylgalactosamine added as the main determining structure, type B has a galactose, and type AB has all three of these antigens. Antigens which are not present in an individual's blood will cause antibodies to be produced, which will bind to the foreign glycolipids. For this reason, people with blood type AB can receive transfusions from all blood types (the universal acceptor), and people with blood type O can act as donors to all blood types (the universal donor).

Glycolipids are lipids with a carbohydrate attached by a glycosidic (covalent) bond. Their role is to maintain the stability of the cell membrane and to facilitate cellular recognition, which is crucial to the immune response and in the connections that allow cells to connect to one another to form tissues. Glycolipids are found on the surface of all eukaryotic cell membranes, where they extend from the phospholipid bilayer into the extracellular environment.

Les glycolipides résultent de la liaison d'un simple hexose ou d'un oligosaccharide à une fonction hydroxyle appartenant soit au glycérol d'un diglycéride (glycéroglycolipide) soit à la sphingosine d'un céramide (sphingolipide).


Early life.

Theophanes was from the town of Mytilene on the island of Lesbos and lived in the middle of the 1st century BC. He played a leading role in resisting Mithridates VI of Pontus on Lesbos in the 80s BC. He met Pompey, the successful, young, Roman general who was nicknamed "the Great" ("magnus"), when the latter was using Mytilene as a naval base against pirates in 67BC, and became a member of his retinue.

Pompey's protégé.

Theophanes was one of the most intimate friends of Pompey, whom he accompanied in many of his campaigns, and who frequently followed his advice on public as well as private matters.  Theophanes came to Rome with Pompey after the conclusion of the wars in the east. There he adopted Lucius Cornelius Balbus, of Gades, a favourite of his patron. He continued to live in Pompey's household on the close terms, and we see from Cicero's letters that his society was courted by many of the Roman nobles, on account of his well-known influence with Pompey. When the civil war broke out he accompanied Pompey to Greece, where Pompey appointed him commander of the Fabri, and consulted him and Lucceius on all important matters in the war, much to the indignation of the Roman nobles. After the Battle of Pharsalus Theophanes fled with Pompey from Greece, and it was owing to his advice that Pompey went to Egypt, where he was killed. After the death of Pompey, Theophanes took refuge in Italy. He was pardoned by Julius Caesar, and was still alive in 44 BC, as evidenced by one of Cicero's letters.

History of Pompey's campaigns.

Theophanes wrote the history of Pompey's campaigns. He represented the exploits of his hero in the most favourable light, and did not hesitate, as Plutarch more than hints, to invent a false tale for the purpose of injuring the reputation of an enemy of the Pompeian family.

Death.

Theophanes died in Rome, some time after 44BC. After his death the Lesbians paid divine honours to his memory. Theophanes left behind him a son, Marcus Pompeius Theophanes, whom Augustine sent to Asia in the capacity of procurator, and at the time that Strabo wrote the younger Theophanes was one of the friends of Tiberius. The latter emperor, however, put his descendants to death towards the end of his reign, in AD 33, because their ancestor had been one of Pompey's friends, and had received after his death divine honours from the Lesbians. The people of Mytilene commemorated Theophanes as a hero after his death and put his portrait on their bronze coins. From the likeness a marble portrait of the man has been identified as well as dozens of his images in relief on the bottom of special bowls perhaps made to celebrate his posthumous status. Excavations both in the Castle of Mytilene and elsewhere in the town have uncovered a variety of them.

Theophanes of Mytilene () was an intellectual and historian from the town of Mytilene on the island of Lesbos who lived in the middle of the 1st century BC. He was a friend of Pompey and wrote an adulatory history of the latter's expedition to Asia. According to Plutarch Pompey granted privileges to Mytilene for Theophanes' sake. The people of Mytilene commemorated him as a hero after his death.

Théophane (né en 80 av. J.-C., mort en 30 av. J.-C.) est un historien antique d'origine grecque. Il est né dans la cité de Mytilène sur l'île de Lesbos.


The Artemidorus papyrus.

A papyrus containing a fragment already known as part of book 2 of his work has recently been discovered. It is known as the "Artemidorus papyrus"; it also contains the first map of the Iberian peninsula, and many illustrations.  This long papyrus roll was written in the first century BC, maybe in Alexandria. The copyist left spaces for illustrations of maps, and then sent it to a painter's workshop to have them inserted. But the painter designed only a partial map, which appears to be what the author believed was the shape of the southwestern Iberian peninsula.  The map is incomplete and has no names, and is perhaps the wrong map for the space in the papyrus. This ruined the roll. Instead the blank spaces were used as scrap papyrus for rough drafts, and to keep a catalog of drawings for clients. The drawings include pictures of real animals, such as giraffes, tigers and pelicans, as well as mythical ones, such as the griffin, marine snake, or a dog with wings. In addition, pictures of heads, feet and hands were drawn until there were no blank spaces.  The papyrus was then presumably sold as scrap paper. It was found in the early 1900s in the form of cartonnage, as a filling for some kind of cavity ("Konvolut"). The cartonnage was sold to an Egyptian collector in whose hands it remained for fifty years. It then travelled around Europe, before being bought by a German collector who opened it and discovered the remains of the papyrus roll. It has holes in it, but because it got damp at some stage, even when there are holes, the drawings on those parts of the papyrus have been mirrored on the facing part of the roll.  The papyrus - which was bought by a foundation for $3,369,850 - is now owned by Turin's Banco di San Paolo.  A 2007 study by Canfora asserts that the text of the papyrus cannot be by Artemidorus as it contains words not available except in Byzantine Greek, and that the papyrus may be a forgery, perhaps by Constantine Simonides. Richard Janko, in "Classical Review" 59.2 (2009) pp. 403-410 has offered arguments favoring the case for forgery.  In December 2018 the Turin Public Prosecutor's Office confirmed the falsity of the papyrus. Through the investigations arranged by the Ministry of Cultural Heritage (Ministero dei Beni Culturali), the papyrus was decreed to be a forgery of the nineteenth century, attributable to the Greek Constantine Simonidis.

Artemidorus of Ephesus (; ) was a Greek geographer, who flourished around 100 BC. His work in eleven books is often quoted by Strabo. What was thought to be a fragment of his work was determined to be a forgery.

Artémidore (en grec ancien ) dit parfois Artémidore « d'Éphèse », créant une confusion avec Artémidore de Daldis dit aussi « d'Éphèse » est un célèbre géographe grec du.


Description.

While the nuclear force is usually associated with nucleons, more generally this force is felt between hadrons, or particles composed of quarks. At small separations between nucleons (less than ~ 0.7 fm between their centers, depending upon spin alignment) the force becomes repulsive, which keeps the nucleons at a certain average separation. For identical nucleons (such as two neutrons or two protons) this repulsion arises from the Pauli exclusion force. A Pauli repulsion also occurs between quarks of the same flavour from different nucleons (a proton and a neutron).

Field strength.

At distances larger than 0.7 fm the force becomes attractive between spin-aligned nucleons, becoming maximal at a center–center distance of about 0.9 fm. Beyond this distance the force drops exponentially, until beyond about 2.0 fm separation, the force is negligible. Nucleons have a radius of about 0.8 fm.  At short distances (less than 1.7 fm or so), the attractive nuclear force is stronger than the repulsive Coulomb force between protons; it thus overcomes the repulsion of protons within the nucleus. However, the Coulomb force between protons has a much greater range as it varies as the inverse square of the charge separation, and Coulomb repulsion thus becomes the only significant force between protons when their separation exceeds about 2 to 2.5 fm.  The nuclear force has a spin-dependent component. The force is stronger for particles with their spins aligned than for those with their spins anti-aligned. If two particles are the same, such as two neutrons or two protons, the force is not enough to bind the particles, since the spin vectors of two particles of the same type must point in opposite directions when the particles are near each other and are (save for spin) in the same quantum state. This requirement for fermions stems from the Pauli exclusion principle. For fermion particles of different types, such as a proton and neutron, particles may be close to each other and have aligned spins without violating the Pauli exclusion principle, and the nuclear force may bind them (in this case, into a deuteron), since the nuclear force is much stronger for spin-aligned particles. But if the particles' spins are anti-aligned the nuclear force is too weak to bind them, even if they are of different types.  The nuclear force also has a tensor component which depends on the interaction between the nucleon spins and the angular momentum of the nucleons, leading to deformation from a simple spherical shape.

Nuclear binding.

To disassemble a nucleus into unbound protons and neutrons requires work against the nuclear force. Conversely, energy is released when a nucleus is created from free nucleons or other nuclei: the nuclear binding energy. Because of mass–energy equivalence (i.e. Einstein's formula ), releasing this energy causes the mass of the nucleus to be lower than the total mass of the individual nucleons, leading to the so-called "mass defect".  The nuclear force is nearly independent of whether the nucleons are neutrons or protons. This property is called "charge independence". The force depends on whether the spins of the nucleons are parallel or antiparallel, as it has a non-central or "tensor" component. This part of the force does not conserve orbital angular momentum, which under the action of central forces is conserved.  The symmetry resulting in the strong force, proposed by Werner Heisenberg, is that protons and neutrons are identical in every respect, other than their charge. This is not completely true, because neutrons are a tiny bit heavier, but it is an approximate symmetry. Protons and neutrons are therefore viewed as the same particle, but with different isospin quantum numbers; conventionally, the proton is "isospin up," while the neutron is "isospin down". The strong force is invariant under SU(2) isospin transformations, just as other interactions between particles are invariant under SU(2) transformations of intrinsic spin. In other words, both isospin and intrinsic spin transformations are isomorphic to the SU(2) symmetry group. There are only strong attractions when the total isospin of the set of interacting particles is 0, which is confirmed by experiment.  Our understanding of the nuclear force is obtained by scattering experiments and the binding energy of light nuclei. The nuclear force occurs by the exchange of virtual light mesons, such as the virtual pions, as well as two types of virtual mesons with spin (vector mesons), the rho mesons and the omega mesons. The vector mesons account for the spin-dependence of the nuclear force in this "virtual meson" picture.  The nuclear force is distinct from what historically was known as the weak nuclear force. The weak interaction is one of the four fundamental interactions, and plays a role in processes such as beta decay. The weak force plays no role in the interaction of nucleons, though it is responsible for the decay of neutrons to protons and vice versa.

History.

The nuclear force has been at the heart of nuclear physics ever since the field was born in 1932 with the discovery of the neutron by James Chadwick. The traditional goal of nuclear physics is to understand the properties of atomic nuclei in terms of the 'bare' interaction between pairs of nucleons, or nucleon–nucleon forces (NN forces).  Within months after the discovery of the neutron, Werner Heisenberg and Dmitri Ivanenko had proposed proton–neutron models for the nucleus. Heisenberg approached the description of protons and neutrons in the nucleus through quantum mechanics, an approach that was not at all obvious at the time. Heisenberg's theory for protons and neutrons in the nucleus was a "major step toward understanding the nucleus as a quantum mechanical system." Heisenberg introduced the first theory of nuclear exchange forces that bind the nucleons. He considered protons and neutrons to be different quantum states of the same particle, i.e., nucleons distinguished by the value of their nuclear isospin quantum numbers.  One of the earliest models for the nucleus was the liquid drop model developed in the 1930s. One property of nuclei is that the average binding energy per nucleon is approximately the same for all stable nuclei, which is similar to a liquid drop. The liquid drop model treated the nucleus as a drop of incompressible nuclear fluid, with nucleons behaving like molecules in a liquid. The model was first proposed by George Gamow and then developed by Niels Bohr, Werner Heisenberg, and Carl Friedrich von Weizsäcker. This crude model did not explain all the properties of the nucleus, but it did explain the spherical shape of most nuclei. The model also gave good predictions for the binding energy of nuclei.  In 1934, Hideki Yukawa made the earliest attempt to explain the nature of the nuclear force. According to his theory, massive bosons (mesons) mediate the interaction between two nucleons. In light of quantum chromodynamics (QCD)—and, by extension, the Standard Model—meson theory is no longer perceived as fundamental. But the meson-exchange concept (where hadrons are treated as elementary particles) continues to represent the best working model for a quantitative "NN" potential. The Yukawa potential (also called a screened Coulomb potential) is a potential of the form  where "g" is a magnitude scaling constant, i.e., the amplitude of potential, formula_2 is the Yukawa particle mass, "r" is the radial distance to the particle. The potential is monotone increasing, implying that the force is always attractive. The constants are determined empirically. The Yukawa potential depends only on the distance between particles, "r", hence it models a central force.  Throughout the 1930s a group at Columbia University led by I. I. Rabi developed magnetic resonance techniques to determine the magnetic moments of nuclei. These measurements led to the discovery in 1939 that the deuteron also possessed an electric quadrupole moment. This electrical property of the deuteron had been interfering with the measurements by the Rabi group. The deuteron, composed of a proton and a neutron, is one of the simplest nuclear systems. The discovery meant that the physical shape of the deuteron was not symmetric, which provided valuable insight into the nature of the nuclear force binding nucleons. In particular, the result showed that the nuclear force was not a central force, but had a tensor character. Hans Bethe identified the discovery of the deuteron's quadrupole moment as one of the important events during the formative years of nuclear physics.  Historically, the task of describing the nuclear force phenomenologically was formidable. The first semi-empirical quantitative models came in the mid-1950s, such as the Woods–Saxon potential (1954). There was substantial progress in experiment and theory related to the nuclear force in the 1960s and 1970s. One influential model was the Reid potential (1968).  In recent years, experimenters have concentrated on the subtleties of the nuclear force, such as its charge dependence, the precise value of the π"NN" coupling constant, improved phase shift analysis, high-precision "NN" data, high-precision "NN" potentials, "NN" scattering at intermediate and high energies, and attempts to derive the nuclear force from QCD.

The nuclear force as a residual of the strong force.

The nuclear force is a residual effect of the more fundamental strong force, or strong interaction. The strong interaction is the attractive force that binds the elementary particles called quarks together to form the nucleons (protons and neutrons) themselves. This more powerful force, one of the fundamental forces of nature, is mediated by particles called gluons. Gluons hold quarks together through color charge which is analogous to electric charge, but far stronger. Quarks, gluons, and their dynamics are mostly confined within nucleons, but residual influences extend slightly beyond nucleon boundaries to give rise to the nuclear force.  The nuclear forces arising between nucleons are analogous to the forces in chemistry between neutral atoms or molecules called London forces. Such forces between atoms are much weaker than the attractive electrical forces that hold the atoms themselves together (i.e., that bind electrons to the nucleus), and their range between atoms is shorter, because they arise from small separation of charges inside the neutral atom. Similarly, even though nucleons are made of quarks in combinations which cancel most gluon forces (they are "color neutral"), some combinations of quarks and gluons nevertheless leak away from nucleons, in the form of short-range nuclear force fields that extend from one nucleon to another nearby nucleon. These nuclear forces are very weak compared to direct gluon forces ("color forces" or strong forces) inside nucleons, and the nuclear forces extend only over a few nuclear diameters, falling exponentially with distance. Nevertheless, they are strong enough to bind neutrons and protons over short distances, and overcome the electrical repulsion between protons in the nucleus.  Sometimes, the nuclear force is called the residual strong force, in contrast to the strong interactions which arise from QCD. This phrasing arose during the 1970s when QCD was being established. Before that time, the "strong nuclear force" referred to the inter-nucleon potential. After the verification of the quark model, "strong interaction" has come to mean QCD.

Nucleon–nucleon potentials.

Two-nucleon systems such as the deuteron, the nucleus of a deuterium atom, as well as proton–proton or neutron–proton scattering are ideal for studying the "NN" force. Such systems can be described by attributing a "potential" (such as the Yukawa potential) to the nucleons and using the potentials in a Schrödinger equation. The form of the potential is derived phenomenologically (by measurement), although for the long-range interaction, meson-exchange theories help to construct the potential. The parameters of the potential are determined by fitting to experimental data such as the deuteron binding energy or "NN" elastic scattering cross sections (or, equivalently in this context, so-called "NN" phase shifts).  The most widely used "NN" potentials are the Paris potential, the Argonne AV18 potential, the CD-Bonn potential and the Nijmegen potentials.  A more recent approach is to develop effective field theories for a consistent description of nucleon–nucleon and three-nucleon forces. Quantum hadrodynamics is an effective field theory of the nuclear force, comparable to QCD for color interactions and QED for electromagnetic interactions. Additionally, chiral symmetry breaking can be analyzed in terms of an effective field theory (called chiral perturbation theory) which allows perturbative calculations of the interactions between nucleons with pions as exchange particles.

From nucleons to nuclei.

The ultimate goal of nuclear physics would be to describe all nuclear interactions from the basic interactions between nucleons. This is called the "microscopic" or "ab initio" approach of nuclear physics. There are two major obstacles to overcome:  This is an active area of research with ongoing advances in computational techniques leading to better first-principles calculations of the nuclear shell structure. Two- and three-nucleon potentials have been implemented for nuclides up to "A" = 12.

Nuclear potentials.

A successful way of describing nuclear interactions is to construct one potential for the whole nucleus instead of considering all its nucleon components. This is called the "macroscopic" approach. For example, scattering of neutrons from nuclei can be described by considering a plane wave in the potential of the nucleus, which comprises a real part and an imaginary part. This model is often called the optical model since it resembles the case of light scattered by an opaque glass sphere.  Nuclear potentials can be "local" or "global": local potentials are limited to a narrow energy range and/or a narrow nuclear mass range, while global potentials, which have more parameters and are usually less accurate, are functions of the energy and the nuclear mass and can therefore be used in a wider range of applications.

The nuclear force (or nucleon–nucleon interaction or residual strong force) is a force that acts between the protons and neutrons of atoms. Neutrons and protons, both nucleons, are affected by the nuclear force almost identically. Since protons have charge +1 "e", they experience an electric force that tends to push them apart, but at short range the attractive nuclear force is strong enough to overcome the electromagnetic force. The nuclear force binds nucleons into atomic nuclei.

La force nucléaire, qui s'exerce entre nucléons, est responsable de la liaison des protons et des neutrons dans les noyaux atomiques. Elle peut être interprétée en termes d'échanges de mésons légers, comme les pions. Même si son existence est démontrée depuis les années 1930, les scientifiques n'ont pas réussi à établir une loi permettant de calculer sa valeur à partir de paramètres connus, contrairement aux lois de Coulomb et de Newton.


Fund goals.

The FSN is funded essentially by the State’s grants and by donations by Tunisian citizens and private companies on a totally voluntary basis. Tunisian society reacted with enthusiasm to President Zine El Abidine Ben Ali’s calls upon citizens to show solidarity with the needy. Thus, December 8 of every year—the historical date which marks the launch the Fund—witnesses a steady flow by Tunisians to various donation centers in order to contribute to the Fund.  The goals of the FSN are:  The FSN is funded essentially by the State’s grants and by donations by Tunisian citizens and private companies on a totally voluntary basis. Tunisian society reacted with enthusiasm to President Zine El Abidine Ben Ali’s calls upon citizens to show solidarity with the needy. Thus, December 8 of every year—the historical date which marks the launch the Fund—witnesses a steady flow by Tunisians to various donation centers in order to contribute to the Fund. All the funds collected go towards implementing projects. There are no overhead costs nor are the funds used to pay employees of the fund.

Results.

Ever since its creation till to date, the FSN has realized thousands of projects involving hundreds of millions of Tunisian Dinars in favor of the underprivileged categories, thus meeting most of its objectives. Indeed, the FSN has been able to bring about a perceptible change in the life quality of those categories as well as in the landscape of the once secluded and poor areas. Amongst these realizations are:

The Tunisian National Solidarity Fund (also known as the 26-26 Fund after its postal account number or as FSN) is a public-service institution which relies on both public and private donations for the implementation of development projects in favor of underprivileged social categories and needy individuals. The FSN was created on December 8, 1992, following an unexpected visit by President Zine El Abidine Ben Ali to two secluded and destitute villages, «Zwakra» and «Barrama» in the south-eastern part of the country. That visit was to be the launch pad of a continuing anti-poverty campaign.

Le Fonds de solidarité nationale (FSN) est une institution gouvernementale tunisienne destiné à la collecte de fonds afin de permettre des investissements publics dans des programmes et projets de réduction de la pauvreté. Doté d'environ 0,1 % du PIB tunisien, il est généralement connu sous le régime de Zine el-Abidine Ben Ali sous son numéro de compte postal : 26-26.