The Science Portal
Science is the methodical study of nature including testable explanations and predictions. From classical antiquity through the 19th century, science as a type of knowledge was more closely linked to philosophy than it is now and, in fact, in the Western world, the term "natural philosophy" encompassed fields of study that are today associated with science, such as astronomy, medicine, and physics. However, during the Islamic Golden Age foundations for the scientific method were laid by Ibn al-Haytham in his Book of Optics. While the classification of the material world by the ancient Indians and Greeks into air, earth, fire and water was more philosophical, medieval Middle Easterns used practical, experimental observation to classify materials.
Today, the ever-evolving term "science" refers to the pursuit of knowledge, not the knowledge itself. It is often synonymous with "natural and physical science" and often restricted to those branches of study relating to the phenomena of the material universe and their laws. Although the term implies exclusion of pure mathematics, many university faculties include Mathematics Departments within their Faculty of Science. The dominant sense in ordinary use has a narrower use for the term "science." It developed as a part of science becoming a distinct enterprise of defining the "laws of nature"; early examples include Kepler's laws, Galileo's laws, and Newton's laws of motion. In this period it became more common to refer to natural philosophy as "natural science." Over the course of the 19th century, the word "science" became increasingly associated with the disciplined study of the natural world, including physics, chemistry, geology and biology. This sometimes left the study of human thought and society in a linguistic limbo, which was resolved by classifying these areas of academic study as social science. For example, psychology evolved from philosophy, and has grown into an area of study.
Currently, there are both "hard" (e.g. biological psychology) and "soft" science (e.g. social psychology) fields within the discipline. As a result, and as is consistent with the unfolding of the study of knowledge and development of methods to establish facts, each area of psychology employs a scientific method. Reflecting the evolution of the development of knowledge and established facts and the use of the scientific method, Psychology Departments in universities are found within: Faculty of Arts and Science, Faculty of Arts, and a Faculty of Science. Similarly, several other major areas of disciplined study and knowledge exist today under the general rubric of "science", such as formal science and applied science.
A quantum computer
is any device for computation
that makes direct use of distinctively quantum mechanical
phenomena, such as superposition
, to perform operations on data. In a classical (or conventional) computer, the amount of data
is measured by bits
; in a quantum computer, it is measured by qubits
. The basic principle of quantum computation is that the quantum properties of particles can be used to represent and structure data, and that devised quantum mechanisms can be used to perform operations with this data. For a generally accessible overview of quantum computing, see Quantum Computing with Molecules
, an article in Scientific American
by Neil Gershenfeld
and Isaac L. Chuang.
Experiments have already been carried out in which quantum computational operations were executed on a very small number of qubits. Research in practical areas continues at a frantic pace; see Quantum Information Science and Technology Roadmap for a sense of where the research is heading. Many national government and military funding agencies support quantum computing research, to develop quantum computers for both civilian and national security purposes, such as cryptanalysis.
A plasma globe is usually a clear glass orb, filled with a mixture of various inert gases at low pressure, and driven by high frequency alternating current at high voltage (approx. 35 kHz, 2–5 kV,15.7 Krem), generated by a high voltage transformer. A much smaller orb in its centre serves as an electrode. Beams or snakes of "light" (actually emergent patterns in ionized gas) extend from the inner electrode to the outer glass container, giving an appearance similar to multiple constant beams of coloured lightning. The beams first follow the electric field lines of the dipole, but move up due to convection.
Isaac Newton, English physicist
. A man of profound genius
, he is widely regarded as the most influential scientist in history. He is associated with the scientific revolution
and the advancement of heliocentrism
. Among his scientific accomplishments, Newton wrote the Philosophiae Naturalis Principia Mathematica
, wherein he described universal gravitation
and, via his laws of motion
, laid the groundwork for classical mechanics
. With Gottfried Wilhelm Leibniz
he is credited for the development of differential calculus
. Newton was the first to promulgate a set of natural laws that could govern both terrestrial
motion and celestial motion
, and is credited with providing mathematical substantiation for Kepler's laws of planetary motion
, which he expanded by arguing that orbits
(such as those of comets
) could include all conic sections (such as the ellipse
, and parabola
- ...that acoustic levitation is a method for suspending matter in a fluid by using acoustic radiation pressure from intense sound waves in the medium?
- ...that a successful experimental system must be stable and reproducible enough for scientists to make sense of the system's behavior, but unpredictable enough that it can produce useful results?