Ice

Ice is water frozen into a solid state. Depending on the presence of impurities such as particles of soil or bubbles of air, it can appear transparent or a more or less opaque bluish-white color.

In the Solar System, ice is abundant and occurs naturally from as close to the Sun as Mercury to as far as the Oort cloud. Beyond the Solar System, it occurs as interstellar ice. It is abundant on Earth's surface – particularly in the polar regions and above the snow line – and, as a common form of precipitation and deposition, plays a key role in Earth's water cycle and climate. It falls as snowflakes and hail or occurs as frost, icicles or ice spikes.

Ice molecules can exhibit up to sixteen different phases (packing geometries) that depend on temperature and pressure. When water is cooled rapidly (quenching), up to three different types of amorphous ice can form depending on the history of its pressure and temperature. When cooled slowly correlated proton tunneling occurs below 20 K giving rise to macroscopic quantum phenomena. Virtually all the ice on Earth's surface and in its atmosphere is of a hexagonal crystalline structure denoted as ice Ih (spoken as "ice one h") with minute traces of cubic ice denoted as ice Ic. The most common phase transition to ice Ih occurs when liquid water is cooled below 0°C (273.15K, 32°F) at standard atmospheric pressure. It may also be deposited directly by water vapor, as happens in the formation of frost. The transition from ice to water is melting and from ice directly to water vapor is sublimation.

Ice (1998 film)

Ice is a 1998 television disaster film starring Grant Show, Udo Kier, and Eva La Rue. The film has a similar premise as The Day After Tomorrow, a science fiction disaster film released six years later. Though completely in English, it first premiered in Germany in 1998 before being aired on ABC in the United States in 2000.

Plot

A small meteor hits the sun, causing disastrous consequences for the Earth. Los Angeles is, just as the rest of the world, covered with a layer of ice and snow. The government has collapsed and everyone is on their own. Chaos and crime prevails. Together with scientist Dr. Kistler and a small group of survivors, L.A. cop Robert Drake leaves in the direction of Long Beach Harbor to meet with a government ship which will take them to Guam, where it is warmer.

Cast

Ice (band)

Ice is an industrial music band formed by guitarist Justin Broadrick and saxophonist/vocalist Kevin Martin.

History

Keeping to a similar vein as their other musical project Techno Animal, Justin Broadrick and Kevin Martin opted for Ice to be a studio-based project. Drummer John Jobaggy and bassist Dave Cochrane were recruited to aid them in the recording process. Their debut album, Under the Skin, is comparable to Pure-era Godflesh and Martin's free jazz and dub work with God. The group went on hiatus for several years and Jobaggy was replaced by Laika drummer Lou Ciccotelli. By their second album, Bad Blood, the band had absorbed hip hop influences and nearly all the songs featured contributions from recognizable names in the underground rap scene. Blixa Bargeld, of Einsturzende Neubauten, also contributed his vocals to the music.

Band members

Discography

*-algebra

In mathematics, and more specifically in abstract algebra, a *-algebra (or involutive algebra) is a mathematical structure consisting of two involutive rings R and A, where R is commutative and A has the structure of an associative algebra over R. Involutive algebras generalize the idea of a number system equipped with conjugation, for example the complex numbers and complex conjugation, matrices over the complex numbers and conjugate transpose, and linear operators over a Hilbert space and Hermitian adjoints.

Terminology

*-ring

In mathematics, a *-ring is a ring with a map * : A → A that is an antiautomorphism and an involution.

More precisely, * is required to satisfy the following properties:

for all x, y in A.

This is also called an involutive ring, involutory ring, and ring with involution. Note that the third axiom is actually redundant, because the second and fourth axioms imply 1* is also a multiplicative identity, and identities are unique.

Algebra (disambiguation)

The word 'algebra' is used for various branches and structures of mathematics. For their overview, see Algebra.

The bare word "algebra"

The bare word "algebra" can mean:

In universal algebra, algebra has an axiomatic definition, roughly as an instance of any of a number of algebraic structures, such as groups, rings, etc.

Branches of mathematics

The term is also traditionally used for the field of:

Mathematical structures

Vector space with multiplication

Some notable algebras in this sense are:

Mathematics education in the United States

From kindergarten through high school, the mathematics education in public schools in the United States has historically varied widely from state to state, and often even varies considerably within individual states. With the recent adoption of the Common Core Standards by 45 states, mathematics content across the country is moving into closer agreement for each grade level.

Curricular content

Each state sets its own curricular standards and details are usually set by each local school district. Although there are no federal standards, 45 states have agreed to base their curricula on the Common Core State Standards in mathematics beginning in 2015. The National Council of Teachers of Mathematics (NCTM) published educational recommendations in mathematics education in 1991 and 2000 which have been highly influential, describing mathematical knowledge, skills and pedagogical emphases from kindergarten through high school. The 2006 NCTM Curriculum Focal Points have also been influential for its recommendations of the most important mathematical topics for each grade level through grade 8.