Differential

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Differential may refer to:

Contents 1 Medicine 2 Mathematics 3 Natural sciences and engineering 4 Social sciences 5 Other uses

[edit] Medicine

• Differential diagnosis refers to the characterization of the underlying cause of pathological states based on specific tests.

• Differential WBC count is the enumeration of each type of white blood cells either manually or using automated analyzers.

[edit] Mathematics

• Differential (calculus), multiple related meanings in calculus and differential geometry, such as an infinitesimal change in the value of a function

• In traditional approaches to calculus, the differential of a function represents an infinitesimal change in its value and employs the dx, dy, dt, symbols.
• In differential geometry, differentials represent the exterior derivatives of the coordinate functions on a differentiable manifold.

• Differential (coboundary), in homological algebra and algebraic topology, one of the maps of a cochain complex
• Differential (cryptography), in differential cryptanalysis, a pair consisting of the difference, usually computed by XOR (exclusive or), between two plaintexts, and the difference of the corresponding ciphertexts

See also derivative, differential calculus.

[edit] Natural sciences and engineering

• Differential (mechanical device). As part of a powertrain, the device that allows each of the driving wheels to rotate at different speeds.
• Electronic Differential, an electric motor controller which substitutes its mechanical counterpart with significant advantages in electric vehicle application.
• In electronics, differential signaling applies to a method of transmitting electronic signals over a pair of wires to improve noise immunity.

[edit] Social sciences

• Semantic and structural differentials in psychology
• A quality spread differential in finance
• Compensating differential in labor economics

[edit] Other uses

The word differential is also used in many fields as an adjective to refer to differences, particularly those of a variable or continuous nature. Examples include differential hardening in metallurgy, differential rotation in astronomy, differential centrifugation in cell biology, differential scanning calorimetry in materials science, differential signalling in communications, differential algebra in mathematics, differential execution in computer science, and differential GPS technology.