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Phlogiston theory

The phlogiston theory once put forward the belief that there was a fire-like element called phlogiston inside combustible bodies which was released during combustion. When the substances burned, the phlogiston escaped leaving a solid ash called c ...

                                               

Plutonism

Plutonism is the theory that the rocks forming the Earth were formed in fire by volcanic activity. It was named after Pluto, the classical ruler of the underworld, or alternatively after Vulcan, the ancient Roman god of fire and volcanoes. The th ...

                                               

Uniformitarianism

Uniformitarianism is the idea that the same physical laws of today have always operated. It was the centerpiece of James Huttons 1795 geology book Theory of the Earth, with proofs and illustrations. In this work Hutton proposed that the causes ac ...

                                               

Biotechnology

Biotechnology is a technology that involves the use of living organisms. Biotechnology is mainly used in agriculture, food science, and medicine. In biotechnology, living organisms are used to make useful chemicals and products or to perform an i ...

                                               

Media studies

Media studies is an academic area of study about mass media and its history and effects. It mostly focuses on newspapers, radio, television, and internet. Media studies take some ideas from other areas of study, such as humanities and the social ...

                                               

Scientific model

A scientific model is a simplified abstract view of a complex reality. Scientific models are used as a basis for scientific work. They can be used to explain, predict, and test, or to develop computer programs or mathematical equations. An exampl ...

                                               

Angle

When two straight lines come together, they make an angle. The two lines are called the sides of the angle, and they meet at a point. A flat surface also forms an angle when it meets another. To represent an angle, Greek letters such as α {\displ ...

                                               

Mathematics

Mathematics is the study of numbers, shapes and patterns. The word comes from the Greek word "μάθημα", meaning "science, knowledge, or learning", and is sometimes shortened to maths or math. The short words are often used for arithmetic, geometry ...

                                               

0.999.

0.999. is one of the ways the number 1 can be written. Even though it is written like this, no matter how many nines there are before the ellipsis, it is still equal in value to 1.

                                               

4 (number)

In mathematics, the number four is an even number and the smallest composite number. Four is also the second square number after one. A small minority of people have four fingers and four toes, on each hand and foot, respectively. This proves dif ...

                                               

Absolute value

In mathematics, the absolute value or modulus of a real number x, written as | x | or abs {\displaystyle {\text{abs}}}, is the non-negative value of x when the sign is dropped. That is, | x | = x for a positive x, | x | = − x for a negative x, an ...

                                               

Aleph null

Aleph null is the smallest infinite number. It is the cardinality of the set of natural numbers. Georg Cantor invented and named the concept. The symbol for aleph null is ℵ 0 {\displaystyle \aleph _{0}}. It is the first infinite number in a serie ...

                                               

Algebraic geometry

Algebraic geometry is a branch of mathematics studying polynomial equations. Modern algebraic geometry is based on more abstract techniques of abstract algebra, especially commutative algebra, with the language and the problems of geometry. The m ...

                                               

Algebraic variety

In mathematics, algebraic varieties are one of the central objects of study in algebraic geometry. The first definitons of algebraic variety defined it as the set of solutions of a system of polynomial equations, over the real or complex numbers. ...

                                               

Algorithmic information theory

Algorithmic information theory is a field of theoretical computer science. It is concerned with how information and computation are related. Most information can be represented as a String. Algorithmic information theory studies the complexity of ...

                                               

Alphabet (computer science)

In computer science, an alphabet is a finite non-empty set. The elements of an alphabet are called the letters or symbols of the alphabet. An example of an alphabet is { −, ⋅ } {\displaystyle \{-,\cdot \}} which may be used for Morse code or {beg ...

                                               

Applied mathematics

Applied mathematics is a field of mathematics which uses mathematics to solve problems of other branches of science. There are many fields: Numerical analysis and simulation: This field investigates various algorithms to get approximations for ma ...

                                               

Argument

An argument is an attempt to persuade someone of something. Reasons are given to accept the conclusion. The general structure of an argument in a natural language is that premises support the claim or conclusion.

                                               

Arithmetic precision

The precision of a numeric value describes the number of digits that are used to show that value. In a scientific setting, this would be the total number of digits or, less commonly, the number of fractional digits or decimal places. This second ...

                                               

Associativity

Associative property is a property of mathematical operations. It means that if you have more than one of the same associative operator in a row, the order of operations does not matter. For example, if you have 2 + 5 + 10 {\displaystyle 2+5+10\ ...

                                               

Automaton

An Automaton is a concept from mathematics. Sometimes the concept is called state machine. It is like an abstract machine. Such a machine can be given input, which is either rejected, or accepted. Its like a vending machine. When something is bou ...

                                               

Average

An average is the "normal" number of a group of numbers made by mixing the group of numbers. In math, an average is called a mean. It can be found by adding the numbers, then dividing the answer by the number of numbers there were. There are othe ...

                                               

Axiom

An axiom is a concept in logic. It is a statement which is assumed to be true without question, and which does not require proof. It is also known as a postulate. The axiom is to be used as the premise or starting point for further reasoning or a ...

                                               

Babylonian numerals

Babylonian cuneiform numerals were written in cuneiform, using a wedge-tipped reed stylus to make a mark on a soft clay tablet which would be exposed in the sun to harden to create a permanent record. The Babylonians, who were famous for their as ...

                                               

Banach–Tarski paradox

The Banach–Tarski paradox is a theorem in mathematics that says that any solid shape can be reassembled into any other solid shape. It was made by mathematicians Stefan Banach and Alfred Tarski. For example, a sphere can be split up into a limite ...

                                               

Base (mathematics)

In mathematics, a base or radix is the number of different digits or combination of digits and letters that a system of counting uses to represent numbers. For example, the most common base used today is the decimal system. Because "dec" means 10 ...

                                               

Base ten block

Base ten blocks are a tool to help students learn concepts in mathematics such as arithmetic and place value. They are also known as multibase arithmetic blocks MABs or Dienes blocks after the Hungarian mathematician Zoltan Pal Dienes, who told o ...

                                               

Bayes theorem

In probability theory and applications, Bayes theorem shows the relation between a conditional probability and its reverse form. For example, the probability of a hypothesis given some observed pieces of evidence, and the probability of that evid ...

                                               

Bayesian network

A Bayesian network is a kind of graph which is used to model events that cannot be observed. This can then be used for inference. The graph that is used is directed, and does not contain any cycles. The nodes of the graph represent random variabl ...

                                               

Big O notation

In mathematics and computer science, Big O notation is a way of comparing rates of growth of different functions. It is often used to compare the efficiency of different algorithms, which is done by calculating how much memory is needed, and how ...

                                               

Binary

Binary is base 2 number system. It is base 2 because it uses two possible numbers: 0 and 1. Decimal, the system most of the world uses for daily life, is a base 10 system – it uses 10 characters. When binary numbers are written, a subscript " is ...

                                               

Binary adder

Full adders are devices used to add binary numbers. They are used in computers. They take two binary numbers and put them together to get a sum. In its most basic form, it uses two XOR gates, two AND gates, and an OR gate. These gates figure out ...

                                               

Binary operation

In mathematics, a binary operation, often denoted *, on a set is a way of combining a pair of elements in that set that results in another element of the set. For example, if we take a pair of natural numbers and let the operation * be addition, ...

                                               

Binomial expansion

Binomial expansion uses an expression to make a series. It uses a bracket expression like n {\displaystyle ^{n}}. There are three binomial expansions.

                                               

Canonical form

In mathematics and computer science the term Canonical form, or sometimes Normal form refers to the usual representation of a mathematical object. For example, the canonical form of a positive integer in decimal representation is a finite sequenc ...

                                               

Category theory

Category theory is a type of mathematics. Category theorists show how different ideas in mathematics are alike. For example, some ideas from topology and abstract algebra are similar. Ideas in category theory are written down in formulas or diagr ...

                                               

Cellular automaton

A cellular automaton is a model used in computer science and mathematics. The idea is to model a dynamic system by using a number of cells. Each cell has one of several possible states. With each "turn" or iteration the state of the current cell ...

                                               

Chaos theory

Chaos theory is a part of mathematics. It looks at certain systems that are very sensitive. A very small change may make the system behave completely differently. Very small changes in the starting position of a chaotic system make a big differen ...

                                               

Charge conjugation

Charge conjugation describes a type of symmetry of nature. To preform a charge conjugation, one would exchange all particles with their corresponding antiparticles. This action would create a physical system where everything would be the same exc ...

                                               

Clay Mathematics Institute

The Clay Mathematics Institute is a private, non-profit foundation, based in Cambridge, Massachusetts. The Institute is dedicated to increasing and disseminating mathematical knowledge. It gives out various awards and sponsorships to promising ma ...

                                               

Closure (mathematics)

In mathematics, closure describes the case when the results of a mathematical operation are always defined. For example, in ordinary arithmetic, addition on real numbers has closure: whenever one adds two numbers, the answer is a number. The same ...

                                               

Combination (mathematics)

In mathematics, combination is used for picking a number of objects from a given set of objects. Combinatorics looks at the number of possibilities to pick k objects from a set of n. It does not take into account the order in which these are pick ...

                                               

Combinatorics

Combinatorics is a branch of mathematics. It is concerned with finite or countable infinite sets. Combinatorics is part of discrete mathematics. Combinatorics are about graph theory, or Partitions of sets. According to George Polya, combinatorics ...

                                               

Commutative property

The commutative property says that the order of the numbers when adding or multiplying can be changed without changing the answer. For example, both 2 + 8 {\displaystyle 2+8} and 8 + 2 {\displaystyle 8+2} are equal to 10, and both 5 ∗ 7 {\display ...

                                               

Complexity class

A Complexity class is a concept from theoretical computer science and mathematics: All problems that have the same complexity are in the same complexity class. This means, that for a given input, they need about the same amount of resources, such ...

                                               

Continuous function

A mathematical function is called continuous if, roughly said, a small change in the input only causes a small change in the output. If this is not the case, the function is discontinuous. Functions defined on the real numbers, with one input and ...

                                               

Contraposition

In logic and math, contraposition is the right way to reverse "if-then" statements. For example, the contrapositive of the sentence "If it is raining, then I wear my coat" is the sentence "If I dont wear my coat, then it isnt raining." If the ori ...

                                               

Coprime

In mathematics, two integers are co-prime if they share no common factors. This is sometimes written as a ⊥ b {\displaystyle a\perp b}. In other words, there is no number, other than 1, that divides both a and b evenly. In which case, the greates ...

                                               

Correlation

In statistics and probability theory, correlation is a way to indicate how closely related two sets of data are. Correlation does not always mean that one causes the other. In fact, it is very possible that there is a third factor involved. Corre ...

                                               

Counting

The person counting in English usually starts with the number one, and gives this number to the first thing. The next thing is given the number two. Then, the next thing is given the number three. If there is another thing, it gets the number fou ...

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Pino - logical board game which is based on tactics and strategy. In general this is a remix of chess, checkers and corners. The game develops imagination, concentration, teaches how to solve tasks, plan their own actions and of course to think logically. It does not matter how much pieces you have, the main thing is how they are placement!

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