enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Expansion of the universe - Wikipedia

    en.wikipedia.org/wiki/Expansion_of_the_universe

    Because of the high rate of expansion, it is also possible for a distance between two objects to be greater than the value calculated by multiplying the speed of light by the age of the universe. These details are a frequent source of confusion among amateurs and even professional physicists. [ 33 ]

  3. Cosmological horizon - Wikipedia

    en.wikipedia.org/wiki/Cosmological_horizon

    It represents the boundary between the observable and the unobservable regions of the universe, so its distance at the present epoch defines the size of the observable universe. Due to the expansion of the universe, it is not simply the age of the universe times the speed of light, as in the Hubble horizon, but rather the speed of light ...

  4. Accelerating expansion of the universe - Wikipedia

    en.wikipedia.org/wiki/Accelerating_expansion_of...

    The accelerated expansion of the universe is thought to have begun since the universe entered its dark-energy-dominated era roughly 5 billion years ago. [ 8 ] [ notes 1 ] Within the framework of general relativity , an accelerated expansion can be accounted for by a positive value of the cosmological constant Λ , equivalent to the presence of ...

  5. Faster-than-light - Wikipedia

    en.wikipedia.org/wiki/Faster-than-light

    According to Hubble's law, the expansion of the universe causes distant galaxies to recede from us faster than the speed of light. However, the recession speed associated with Hubble's law , defined as the rate of increase in proper distance per interval of cosmological time , is not a velocity in a relativistic sense.

  6. Particle horizon - Wikipedia

    en.wikipedia.org/wiki/Particle_horizon

    Much like the concept of a terrestrial horizon, it represents the boundary between the observable and the unobservable regions of the universe, [1] so its distance at the present epoch defines the size of the observable universe. [2] Due to the expansion of the universe, it is not simply the age of the universe times the speed of light ...

  7. Big Bang - Wikipedia

    en.wikipedia.org/wiki/Big_Bang

    Since the universe has a finite age, and light travels at a finite speed, there may be events in the past whose light has not yet had time to reach earth. This places a limit or a past horizon on the most distant objects that can be observed. Conversely, because space is expanding, and more distant objects are receding ever more quickly, light ...

  8. Speed of light - Wikipedia

    en.wikipedia.org/wiki/Speed_of_Light

    By adopting Einstein synchronization for the clocks, the one-way speed of light becomes equal to the two-way speed of light by definition. [20] [21] The special theory of relativity explores the consequences of this invariance of c with the assumption that the laws of physics are the same in all inertial frames of reference.

  9. Horizon problem - Wikipedia

    en.wikipedia.org/wiki/Horizon_problem

    In accepted relativistic physical theories, no information can travel faster than the speed of light. In this context, "information" means "any sort of physical interaction". For instance, heat will naturally flow from a hotter area to a cooler one, and in physics terms, this is one example of information exchange.