# Mathematical notation

Mathematical notation is used in mathematics, and throughout the physical sciences, engineering, and economics. The complexity of such notation ranges from relatively simple symbolic representations, such as one and two; to conceptual symbols, such as + and dy/dx; to equations, functions, and variables.

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## Definition

The media used for writing is recounted below, but common materials currently include paper and pencil, or perhaps computer screen and keyboard, as well as board and chalk. One key point behind mathematical notation is the systematic adherence to mathematical concepts as recounted below. (But see also some related concepts: Topic (linguistics), Logical argument, Cogency, ... ... ...)

## Expressions

A mathematical expression is a sequence of symbols which can be evaluated. For example, if the symbols represent numbers, the expressions are evaluated according to a conventional order of operations which provides for calculation, if possible, of any expressions within parentheses, followed by any multiplications and divisions done from left to right, finally any additions or subtractions done from left to right. In a computer language, these rules are implemented by the compilers. For more on expression evaluation, see for example, the computer science topics: eager evaluation, lazy evaluation, evaluation operator. ...

## Precise semantic meaning

See model (abstract)#Abstract models vs models in mathematics

Precision is necessary so that we can know what we are investigating. Suppose that we have statements, denoted by some formal sequence of symbols, about some objects (for example, numbers, shapes, patterns). Until the statements can be shown to be valid, their meaning is not yet resolved. While reasoning, we might let the denoted symbols refer to those objects, perhaps in a model. The semantics of that object has a heuristic side and a deductive side. In either case, we might want to know the properties of that object, which we might then list.

Those properties might then be expressed by some well-known and agreed-upon symbols from a table of mathematical symbols. This mathematical notation might include annotation such as

• "All x", "No x", "There is an x" (or its equivalent, "Some x"), "A set", "A function"
• "A mapping from the real numbers to the complex numbers"
• ...

## Counting

It is believed that a mathematical notation was first developed at least 50,000 years ago in order to assist with counting. Early mathematical ideas for counting were represented by collections of rocks, sticks, bone, clay, stone, wood carvings, and knotted ropes. The tally stick is a timeless way of counting. Perhaps the oldest known mathematical texts are those of ancient Sumer. The Census Quipu of the Andes and the Ishango Bone from Africa both used the tally mark method of accounting for numerical concepts.

## Geometry becomes analytic

The mathematical viewpoints in geometry did not lend themselves well to counting. The natural numbers, their relationship to fractions, and the identification of continuous quantities actually took millennia to take form, much less allow for the development of notation. It was not until the invention of analytic geometry by René Descartes that geometry became more subject to a numerical notation. However, some symbolic shortcuts for mathematical concepts came to be used in the publication of geometric proofs, for example. The power and authority of the custom of geometrical style of Theorem and Proof was even followed by Isaac Newton's Principia Mathematica, though he did not use geometry to invent his concepts, but instead blazed a new trail through the invention of calculus to understand the System of the World.

## Counting is mechanized

After the rise of Boolean algebra and the development of positional notation, it became possible to mechanize simple circuits for counting, first by mechanical means, such as gears and rods, using rotation and translation to represent changes of state, then by electrical means, using changes in voltage and current to represent the analogs of quantity. Today, of course, computers use standard circuits to both store and change quantities, which represent not only numbers, but pictures, sound, motion, and control.

## Computerized notation

The rise of expression evaluators such as calculators and slide rules were only part of what was required to mathematicize civilization. Today, keyboard-based notations are used for the e-mail of mathematical expressions, the Internet shorthand notation. The wide use of programming languages, which teach their users the need for rigor in the statement of a mathematical expression (or else the compiler will not accept the formula) are all contributing toward a more mathematical viewpoint across all walks of life.

There is a part of mathematics which is not algebraic, but which seems to use a different faculty of the mind. For those people with such minds and imaginations, like Isaac Newton's, if they are to benefit from the wide availability of mathematical devices, then they will need to be served by more graphical, visual, aural, tactile, and temporal modalities in notation, as a first step.

## Ideographic notation

In the history of writing, ideographic symbols arose first, as more-or-less direct renderings of some concrete item. This has come full circle with the rise of the computer visualization systems, which can be applied to abstract visualizations as well, such as for rendering some projections of a Calabi-Yau manifold.

Examples of abstract visualization which properly belong to the mathematical imagination, can be found, for example in computer graphics. The need for such models abounds, for example, when the measures for the subject of study are actually random variables and not really ordinary mathematical functions.

## Notes

• Art and Cultures
• Countries of the World (http://www.academickids.com/encyclopedia/index.php/Countries)
• Space and Astronomy