There is considerable speculation as to why the observable universe is apparently composed almost entirely of matter ( as opposed to a mixture of matter and antimatter ), whether there exist other places that are almost entirely composed of antimatter instead, and what sorts of technology might be possible if antimatter could be harnessed.

As a general rule, the higher tablelands lie to the east and south, while a progressive diminution in altitude towards the west and north is observable.

Abstractions may be formed by reducing the information content of a concept or an observable phenomenon, typically to retain only information which is relevant for a particular purpose.

In other words, it is quite possible that actual existence may be ... an efficient cause of observable effects ...." He then launches into a history of attempts to conceptualize the inconceivable from the ancient Greeks to the present.

Self-adjoint operators, where A = A < sup >†</ sup >, play an important role in quantum mechanics ; for example, an observable is always described by a self-adjoint operator.

This means that there is no observable difference between the gravitational field of such a black hole and that of any other spherical object of the same mass.

If a state is not observable, the controller will never be able to determine the behaviour of an unobservable state and hence cannot use it to stabilize the system.

That is, if one of the eigenvalues of the system is not both controllable and observable, this part of the dynamics will remain untouched in the closed-loop system.

In cosmology, cosmic microwave background ( CMB ) radiation ( also CMBR, CBR, MBR, and relic radiation ) is thermal radiation filling the observable universe almost uniformly.

There is a common interest in the processes ( often of a linguistic or symbolic kind ) that give rise to observable phenomena and here there is some mutual influence among the different versions of critical theory.

A corona is a type of plasma " atmosphere " of the Sun or other celestial body, extending millions of kilometers into space, most easily seen during a total solar eclipse, but also observable in a coronagraph.

The F-corona ( F for Fraunhofer ) is created by sunlight bouncing off dust particles, and is observable because its light contains the Fraunhofer absorption lines that are seen in raw sunlight ; the F-corona extends to very high elongation angles from the Sun, where it is called the zodiacal light.

In addition, if the particles of which it is composed are supersymmetric, they can undergo annihilation interactions with themselves resulting in observable by-products such as photons and neutrinos (" indirect detection ").

The Deccan Traps region was reduced to its current size by erosion and plate tectonics ; the present area of directly observable lava flows is around.

An observable a is a function that to each point of the phase space associates a number ( say instantaneous pressure, or average height ).

In scientific use the term empirical refers to the gathering of data using only evidence that is observable by the senses or in some cases using calibrated scientific instruments.

What early philosophers described as empiricist and empirical research have in common is the dependence on observable data to formulate and test theories and come to conclusions.

This phenomenon is easily observable when comparing skimmed milk, which contains little fat, to cream, which contains a much higher concentration of milk fat.

The concept first popularized by Karl Popper, who, in his philosophical criticism of the popular positivist view of the scientific method, concluded that a hypothesis, proposition, or theory talks about the observable only if it is falsifiable.

If confirmed, this would imply special relativity is an approximation to a more general theory, but since the relevant comparison would ( by definition ) be outside the observable universe, it is difficult to imagine ( much less construct ) experiments to test this hypothesis.

For example, observable physical quantities are represented by self-adjoint operators, such as energy or momentum, whereas transformative processes are represented by unitary linear operators such as rotation or the progression of time.

then this expression gives the expectation value, or mean or average value, of the observable represented by operator A for the physical system in the state.

: The expected value ( in the sense of probability theory ) of the observable A for the system in state represented by the unit vector H is

Each observable is represented by a maximally Hermitian ( precisely: by a self-adjoint ) linear operator acting on the state space.

The town was built on the southern declivity, and was surrounded by a wall, which, allowing for the natural irregularities of the soil, represented a triangle, with the castle at the summit — a form observable in many of the ancient cities of Greece.

Another postulate of quantum mechanics is that all observables are represented by operators which act on the wavefunction, and the eigenvalues of the operator are the values the observable takes.

To be more precise, the dynamical variable / observable is a ( not necessarily bounded ) Hermitian operator in a Hilbert Space and thus is represented by a Hermitian matrix if the space is finite-dimensional.

In an infinite-dimensional Hilbert space, the observable is represented by a symmetric operator, which may not be defined everywhere ( i. e. its domain is not the whole space-there exist some states that are not in the domain of the operator ).

Physically, this is the statement that any quantum state can always be represented as a superposition of the eigenstates of an observable.

The state of Operating Thetan is represented by a symbol consisting of the letters OT with the T inside the O and each of the points of the T ending at the O's circumference, evoking not only the level's initials but also the medieval O-T map representing the known world and, metaphorically, the entirety of the observable universe, over which a fully developed OT allegedly has immediate control.

The constellations around the South Pole were not observable from north of the equator, by either Babylonians, Greeks, Chinese or Arabs.

However, by identifying clusters of observable properties that are associated with core examples of clitics on the one hand, and core examples of affixes on the other, one can pick out a battery of tests that provide an empirical foundation for a clitic / affix distinction.

The motion of the solar system, and the orientation of the plane of the are aligned with features of the microwave sky, which on conventional thinking are caused by structure at the edge of the observable universe

They have been measured in detail, and match what would be expected if small thermal variations, generated by quantum fluctuations of matter in a very tiny space, had expanded to the size of the observable universe we see today.

" Geological remains from the distant past can, and should, be explained by reference to geological processes now in operation and thus directly observable.

Coronal loops are highly radiating sources of plasma and therefore easy to observe by instruments such as TRACE ; they are highly observable laboratories to study phenomena such as solar oscillations, wave activity and nanoflares.

As a result of this increased factorability of the radix and its divisibility by a wide range of the most elemental numbers ( whereas ten has only two non-trivial factors: 2 and 5, with neither 3 nor 4 ), duodecimal representations fit more easily than decimal ones into many common patterns, as evidenced by the higher regularity observable in the duodecimal multiplication table.

For these, asha was the course of everything observable, the motion of the planets and astral bodies, the progression of the seasons, the pattern of daily nomadic herdsman life, governed by regular metronomic events such as sunrise and sunset.

The value of an observable can be computed at another time by using the evolution function φ < sup > t </ sup >.

After some 25 years of work, his Theory of the Earth ; or an Investigation of the Laws observable in the Composition, Dissolution, and Restoration of Land upon the Globe was read to meetings of the Royal Society of Edinburgh in two parts, the first by his friend Joseph Black on 7 March 1785, and the second by himself on 4 April 1785.

The longitude systems of most of those bodies with observable rigid surfaces have been defined by references to a surface feature such as a crater.

In the latter case, the decay of a radioactive element damages the mineral crystal ; the result, termed a radioactive halo or pleochroic halo, is observable by various techniques, such as thin-section petrography.

The model of heredity was highly contested by other biologists because it implied that heredity was discontinuous, in opposition to the apparently continuous variation observable for many traits.