When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Time in physics - Wikipedia

    en.wikipedia.org/wiki/Time_in_physics

    In the International System of Units (SI), the unit of time is the second (symbol: s). It has been defined since 1967 as "the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom", and is an SI base unit. [12]

  3. Multiple time dimensions - Wikipedia

    en.wikipedia.org/wiki/Multiple_time_dimensions

    The additional dimensions may be similar to conventional time, [1] compactified like the additional spatial dimensions in string theory, [2] or components of a complex time (sometimes referred to as kime). [3] Itzhak Bars has proposed models of a two-time physics, noting in 2001 that "The 2T-physics approach in d + 2 dimensions offers a highly ...

  4. Spacetime - Wikipedia

    en.wikipedia.org/wiki/Spacetime

    In physics, spacetime, also called the space-time continuum, is a mathematical model that fuses the three dimensions of space and the one dimension of time into a single four-dimensional continuum. Spacetime diagrams are useful in visualizing and understanding relativistic effects, such as how different observers perceive where and when events ...

  5. Unit of time - Wikipedia

    en.wikipedia.org/wiki/Unit_of_time

    The amount of time light takes to travel one Planck length. quectosecond: 10 −30 s: One nonillionth of a second. rontosecond: 10 −27 s: One octillionth of a second. yoctosecond: 10 −24 s: One septillionth of a second. jiffy (physics) 3 × 10 −24 s: The amount of time light takes to travel one fermi (about the size of a nucleon) in a ...

  6. SI base unit - Wikipedia

    en.wikipedia.org/wiki/SI_base_unit

    Dimension symbol; second: s time "The second, symbol s, is the SI unit of time. It is defined by taking the fixed numerical value of the caesium frequency, ∆ν Cs, the unperturbed ground-state hyperfine transition frequency of the caesium 133 atom, to be 9 192 631 770 when expressed in the unit Hz, which is equal to s −1." [1]

  7. Dimension - Wikipedia

    en.wikipedia.org/wiki/Dimension

    A temporal dimension, or time dimension, is a dimension of time. ... In physics, three dimensions of space and one of time is the accepted norm. However, ...

  8. Time - Wikipedia

    en.wikipedia.org/wiki/Time

    In physics, time is a fundamental concept to define other quantities, such as velocity. To avoid a circular definition, [16] time in physics is operationally defined as "what a clock reads", specifically a count of repeating events such as the SI second. [6] [17] [18] Although this aids in practical measurements, it does not address the essence ...

  9. Absolute space and time - Wikipedia

    en.wikipedia.org/wiki/Absolute_space_and_time

    Absolute space and time is a concept in physics and philosophy about the properties of the ... Relative space is some movable dimension or measure of the absolute ...