Black hole collisions could help us measure how fast the universe is expanding
A black hole is usually where information goes to disappear—but scientists may have found a trick to use its last moments to tell us about the history of the universe.
A black hole is usually where information goes to disappear—but scientists may have found a trick to use its last moments to tell us about the history of the universe.
Astronomy
Aug 16, 2022
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855
It has been an exciting week with the release of breathtaking photos of our universe by the James Webb Space Telescope (JWST). Images such as the one below give us a chance to see faint distant galaxies as they were more ...
Astronomy
Jul 18, 2022
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"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.
Astronomy
Jul 05, 2022
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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.
General Physics
Jul 04, 2022
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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.
Astronomy
Jun 23, 2022
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1370
Stellar heated gas and dust has an entropy, or information content, with an equivalent energy of 1070 joules, directly comparable to the mc2 equivalent energy of the universe baryon mass. In a study published in Entropy, ...
General Physics
Jun 13, 2022
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55
Using the Subaru telescope, an international team of astronomers have performed deep multi-band photometric observations of a dwarf irregular galaxy known as NGC 6822. Results of the observational campaign, presented May ...
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 ...
Astronomy
Jun 07, 2022
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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.
Space Exploration
Jun 02, 2022
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Classifying celestial objects is a long-standing problem. With sources at near unimaginable distances, sometimes it's difficult for researchers to distinguish between objects such as stars, galaxies, quasars or supernovae.
Astronomy
May 27, 2022
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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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