Search results
Results from the WOW.Com Content Network
The "cosmological constant" is a constant term that can be added to Einstein field equations of general relativity.If considered as a "source term" in the field equation, it can be viewed as equivalent to the mass of empty space (which conceptually could be either positive or negative), or "vacuum energy".
The cosmological constant was originally introduced in Einstein's 1917 paper entitled “The cosmological considerations in the General Theory of Reality”. [2] Einstein included the cosmological constant as a term in his field equations for general relativity because he was dissatisfied that otherwise his equations did not allow for a static universe: gravity would cause a universe that was ...
In cosmology, the cosmological constant problem or vacuum catastrophe is the substantial disagreement between the observed values of vacuum energy density (the small value of the cosmological constant) and the much larger theoretical value of zero-point energy suggested by quantum field theory.
Dark energy is one of the greatest mysteries in science today. One of the simplest explanations is that it is a “cosmological constant” – a result of the energy of empty space itself – an ...
The researchers used a year of observations by the Dark Energy Spectroscopic Instrument (DESI) at Kitt Peak National Observatory in Arizona, which can capture light from 5,000 galaxies simultaneously.
Grigory (or Grigori or Grigorii) Efimovich Volovik (Григорий Ефимович Воловик; born 7 September 1946 [1] in Moscow) is a Russian theoretical physicist, who specializes in condensed matter physics. He is known for the Volovik effect.
For the Lambda-CDM model with a positive cosmological constant (as observed), the universe is predicted to expand forever regardless of whether the total density is slightly above or below the critical density; though other outcomes are possible in extended models where the dark energy is not constant but actually time-dependent. [citation needed]
Different theories of dark energy suggest different values of w, with w < − 1 / 3 for cosmic acceleration (this leads to a positive value of ä in the acceleration equation above). The simplest explanation for dark energy is that it is a cosmological constant or vacuum energy; in this case w = −1.