Lotna

Lotna is a Polish war film released in 1959 and directed by Andrzej Wajda.

Overview

This highly symbolic movie is both the director's tribute to the long and glorious history of the Polish cavalry, as well as a more ambiguous portrait of the passing of an era. Wajda was the son of a Polish Cavalry officer who was murdered by the Soviets during the Katyn massacre.

The horse Lotna represents the entire Romantic tradition in culture, a tradition that had a huge influence in the course of Polish history and the formation of Polish literature. Lotna is Wajda's meditation on the historical breaking point that was 1939, as well as a reflection on the ending of an entire era for literature and culture in Poland and in Europe as a whole. Writing of the film, Wajda states that it "held great hopes for him, perhaps more than any other." Sadly, Wajda came to think of Lotna "a failure as a film."

The film remains highly controversial, as Wajda includes a mythical scene in which Polish horsemen suicidally charge a unit of German tanks, an event that never actually happened.

Ten Speed

Ten Speed may refer to:

Four-velocity

In physics, in particular in special relativity and general relativity, a four-velocity is a four-vector in four-dimensional spacetime that represents the relativistic counterpart of velocity, which is a three-dimensional vector in space.

Physical events correspond to mathematical points in time and space, the set of all of them together forming a mathematical model of physical four-dimensional spacetime. The history of an object traces a curve in spacetime, called its world line. If the object is massive, so that its speed is less than the speed of light, the world line may be parametrized by the proper time of the object. The four-velocity is the rate of change of four-position with respect to the proper time along the curve. The velocity, in contrast, is the rate of change of the position in (three-dimensional) space of the object, as seen by an observer, with respect to the observer's time.

The value of the magnitude of an object's four-velocity, i. e. the quantity obtained by applying the metric tensor g to the four-velocity u, that is ||u||² = u ⋅ u = g_μνu^νu^μ, is always equal to ±c², where c is the speed of light. Whether the plus or minus sign applies depends on the choice of metric signature. For an object at rest its four-velocity is parallel to the direction of the time coordinate with u⁰ = c. A four-velocity is thus the normalized future-directed timelike tangent vector to a world line, and is a contravariant vector. Though it is a vector, addition of two four-velocities does not yield a four-velocity: The space of four-velocities is not itself a vector space.

Index set

In mathematics, an index set is a set whose members label (or index) members of another set. For instance, if the elements of a set A may be indexed or labeled by means of a set J, then J is an index set. The indexing consists of a surjective function from J onto A and the indexed collection is typically called an (indexed) family, often written as (A_j)_j∈J.

Examples

An enumeration of a set S gives an index set , where f : J → S is the particular enumeration of S.

Any countably infinite set can be indexed by .

For , the indicator function on r is the function given by

The set of all the functions is an uncountable set indexed by .

Other uses

In computational complexity theory and cryptography, an index set is a set for which there exists an algorithm I that can sample the set efficiently; i.e., on input 1ⁿ, I can efficiently select a poly(n)-bit long element from the set.

See also

References

Family (Spanish band)

Family was a cult band from Spain in the 1990s. Although initially unsuccessful, Family gradually acquired a fanbase and is now highly recognised in the Spanish underground pop scene. Their only album, Un Soplo en el Corazón has been praised for its poetic lyrics, inspired music and elegant artwork.

Family - Un Soplo en el Corazón (Tracklist)

1. La Noche Inventada (2:24)

2. Nadadora (2:57)

3. Como un Aviador (3:19)

4. En el Rascacielos (2:32)

5. El Bello Verano (2:19)

6. Portugal (2:10)

7. El Buen Vigía (2:05)

8. Viaje a los Sueños Polares (2:53)

9. Al Otro Lado (2:02)

10. Carlos Baila (2:49)

11. Yo TePerdí una Tarde de Abril (3:01)

12. Dame Estrellas O Limones (2:24)

13. El mapa (2:20)

14. Martín se ha ido para siempre (3:09)

Family (band)

Family were an English rock band that formed in late 1966 and disbanded in October 1973. Their style has been characterised as progressive rock, as their sound often explored other genres, incorporating elements of styles such as folk, psychedelia, acid, jazz fusion and rock and roll. The band achieved recognition in the United Kingdom through their albums, club and concert tours and appearances at festivals.

The band's rotating membership throughout its relatively short existence led to a diversity in sound throughout their different albums. Family are also often seen as an unjustly forgotten act, when compared with other bands from the same period and have been described as an "odd band loved by a small but rabid group of fans". Although most of their recordings were issued in the US, the band never achieved any appreciable success there.

History

Early years (1966–1969)