• Bott periodicity theorem
  Bott periodicity theorem
  In mathematics, the Bott periodicity theorem describes a periodicity in the homotopy groups of classical groups, discovered by , which proved to be of foundational significance for much further research, in particular in K-theory of stable complex vector bundles, as well as the stable homotopy...
  
  , mathematical method of describing a periodicity in the homotopy groups of classical groups
• Fokker periodicity blocks
  Fokker periodicity blocks
  Fokker periodicity blocks are a concept in tuning theory used to mathematically relate musical intervals in just intonation to those in equal tuning. They are named after Adriaan Daniël Fokker...
  
  , concept in tuning theory used to mathematically relate musical intervals
• Periodic function
  Periodic function
  In mathematics, a periodic function is a function that repeats its values in regular intervals or periods. The most important examples are the trigonometric functions, which repeat over intervals of length 2π radians. Periodic functions are used throughout science to describe oscillations,...
  
  , a function whose output contains values that repeat periodically
• Periodic table
  Periodic table
  The periodic table of the chemical elements is a tabular display of the 118 known chemical elements organized by selected properties of their atomic structures. Elements are presented by increasing atomic number, the number of protons in an atom's atomic nucleus...
  
  , classification of chemical elements by means of the periodicity of their chemical properties
• Quasiperiodicity
  Quasiperiodicity
  Quasiperiodicity is the property of a system that displays irregular periodicity. Periodic behavior is defined as recurring at regular intervals, such as "every 24 hours". Quasiperiodic behavior is a pattern of recurrence with a component of unpredictability that does not lend itself to precise...
  
  , property of a system that displays irregular periodicity
• Fourier series
  Fourier series
  In mathematics, a Fourier series decomposes periodic functions or periodic signals into the sum of a set of simple oscillating functions, namely sines and cosines...
  
  , mathematical term that decomposes any periodic function or periodic signal into a set of simple oscillating functions
• Principle of periodicity, in Generally Accepted Accounting Principles
  Generally Accepted Accounting Principles
  Generally Accepted Accounting Principles refer to the standard framework of guidelines for financial accounting used in any given jurisdiction; generally known as accounting standards...
  
  
• Redshift periodicity, astronomical term for Redshift quantization
  Redshift quantization
  Redshift quantization is the hypothesis that the redshifts of cosmologically distant objects tend to cluster around multiples of some particular value...
  
  

See also

• Cycle (disambiguation)
• Frequency (disambiguation)
  Frequency (disambiguation)
  Frequency refers to how often an event occurs within a period of time.Frequency may also refer to:- General :* Audio frequency, a periodic vibration whose frequency is audible to the average human...
  
  
• Seasonality
  Seasonality
  In statistics, many time series exhibit cyclic variation known as seasonality, periodic variation, or periodic fluctuations. This variation can be either regular or semi regular....
  
  , periodic variation, or periodic fluctuations
• Simultaneity (disambiguation)
• Synchronicity
  Synchronicity
  Synchronicity is the experience of two or more events that are apparently causally unrelated or unlikely to occur together by chance and that are observed to occur together in a meaningful manner...
  
  , experience of two or more events that are apparently causally unrelated occurring together in a meaningful manner
• Utility frequency
  Utility frequency
  The utility frequency, line frequency or mains frequency is the frequency at which alternating current is transmitted from a power plant to the end-user. In most parts of the world this is 50 Hz, although in the Americas it is typically 60 Hz...
  
  , the frequency at which alternating current (AC) is transmitted from a power plant to the end user