Related topics: universe · dark matter · galaxies · white dwarfs · big bang

Video: The Fingertip Galaxy: Reflecting Euclid in art

"After Euclid's lifetime, it will just be floating in space. What if future beings found Euclid? How would they know anything about the humanity of the people?" says Tom Kitching, lead scientist of Euclid's VIS instrument.

Large Hadron Collider revs up to unprecedented energy level

Ten years after it discovered the Higgs boson, the Large Hadron Collider is about to start smashing protons together at unprecedented energy levels in its quest to reveal more secrets about how the universe works.

The star that survived a supernova

A supernova is the catastrophic explosion of a star. Thermonuclear supernovae, in particular, signal the complete destruction of a white dwarf star, leaving nothing behind. At least that's what models and observations suggested.

Algorithm simulates the intergalactic medium of the universe

The Instituto de Astrofísica de Canarias (IAC) led the development of a new numerical procedure to reproduce the intergalactic medium obtained from a cosmological simulation of 100,000 hours of computation using big data ...

Euclid gains solar power and protection

Spacecraft are not so different to humans—while the sun can be a great source of vital energy, both people and machines must also be protected from its harmful effects.

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Dark energy

In physical cosmology and astronomy, dark energy is a hypothetical form of energy that permeates all of space and tends to increase the rate of expansion of the universe. Dark energy is the most popular way to explain recent observations that the universe appears to be expanding at an accelerating rate. In the standard model of cosmology, dark energy currently accounts for 74% of the total mass-energy of the universe.

Two proposed forms for dark energy are the cosmological constant, a constant energy density filling space homogeneously, and scalar fields such as quintessence or moduli, dynamic quantities whose energy density can vary in time and space. Contributions from scalar fields that are constant in space are usually also included in the cosmological constant. The cosmological constant is physically equivalent to vacuum energy. Scalar fields which do change in space can be difficult to distinguish from a cosmological constant because the change may be extremely slow.

High-precision measurements of the expansion of the universe are required to understand how the expansion rate changes over time. In general relativity, the evolution of the expansion rate is parameterized by the cosmological equation of state. Measuring the equation of state of dark energy is one of the biggest efforts in observational cosmology today.

Adding the cosmological constant to cosmology's standard FLRW metric leads to the Lambda-CDM model, which has been referred to as the "standard model" of cosmology because of its precise agreement with observations. Dark energy has been used as a crucial ingredient in a recent attempt to formulate a cyclic model for the universe.

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