New insights on dark energy

October 2, 2017, Harvard-Smithsonian Center for Astrophysics
A representation of the evolution of the universe over 13.8 billion years. Different methods of studying cosmic expansion yield slightly different results, including for the age of the universe. Astronomers have calculated that these discrepancies could be reconciled if the dark energy that drives cosmic acceleration were not constant in time. Credit: NASA and the WMAP consortium

The universe is not only expanding - it is accelerating outward, driven by what is commonly referred to as "dark energy." The term is a poetic analogy to label for dark matter, the mysterious material that dominates the matter in the universe and that really is dark because it does not radiate light (it reveals itself via its gravitational influence on galaxies). Two explanations are commonly advanced to explain dark energy. The first, as Einstein once speculated, is that gravity itself causes objects to repel one another when they are far enough apart (he added this "cosmological constant" term to his equations). The second explanation hypothesizes (based on our current understanding of elementary particle physics) that the vacuum has properties that provide energy to the cosmos for expansion.

For several decades cosmologies have successfully used a relativistic equation with and to explain increasingly precise observations about the cosmic microwave background, the cosmological distribution of galaxies, and other large-scale cosmic features. But as the observations have improved, some apparent discrepancies have emerged. One of the most notable is the age of the universe: there is an almost 10% difference between measurements inferred from the Planck satellite data and those from so-called Baryon Acoustic Oscillation experiments. The former relies on far-infrared and submillimeter measurements of the and the latter on spatial distribution of visible galaxies.

CfA astronomer Daniel Eisenstein was a member of a large consortium of scientists who suggest that most of the difference between these two methods, which sample different components of the cosmic fabric, could be reconciled if the dark energy were not constant in time. The scientists apply sophisticated statistical techniques to the relevant cosmological datasets and conclude that if the dark term varied slightly as the universe expanded (though still subject to other constraints), it could explain the discrepancy. Direct evidence for such a variation would be a dramatic breakthrough, but so far has not been obtained. One of the team's major new experiments, the Dark Energy Spectroscopic Instrument (DESI) Survey, could settle the matter. It will map over twenty-five million galaxies in the , reaching back to objects only a few billion years after the big bang, and should be completed sometime in the mid 2020's.

Explore further: New supernova analysis reframes dark energy debate

More information: Gong-Bo Zhao et al. Dynamical dark energy in light of the latest observations, Nature Astronomy (2017). DOI: 10.1038/s41550-017-0216-z

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Molecular hydrogen
1 / 5 (4) Oct 02, 2017
Or it could be a simple answer
1 / 5 (2) Oct 02, 2017
"The universe is not only expanding - it is accelerating outward" from article

"The readings of the ever increasing red shift with the increase of distance between galaxies can support that. If "the most distant objects in the universe are the galaxies GN-z11 13,39 bn ly ..." are also the fastest objects, then, according to Big Bang, these galaxies are also the oldest ones.
The relation is obvious: the greatest speed is related to the oldest and most distant objects.
How can, then, Hubble's law be valid? How can universe be spreading with the increasing speed, if that applies only for the oldest and most distant galaxies?" https://www.acade...eory.doc
Molecular hydrogen
1 / 5 (3) Oct 03, 2017
Ok so the redshift theory does not match scientific observation mmm try this
Molecular hydrogen
1 / 5 (3) Oct 03, 2017
And take a look at this non doppler redshift
Da Schneib
3.4 / 5 (5) Oct 03, 2017
A varying cosmological constant is one possibility. There are others.
Oct 03, 2017
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5 / 5 (3) Oct 03, 2017
Nikola the universe is not expanding into anything. The universe is ALL the space that exist and it's content , by definition. So if there is something to expand into, that something is also part of the universe.
not rated yet Oct 04, 2017
I think Dark Matter and Dark Energy is just the same as normal matter and energy except for one thing - the two are travelling in opposite directions relative to time (so normal matter goes from T=0 to T=infinity, dark matter/energy is going from T=infinity to T=0). I.e. one is going from Order->Chaos (Matter, Light), the other Chaos->Order (DM/DE) - this is why LM emits light, DM absorbs it (it explains where all the anti matter went and why DM is needed to condense and compress matter - the universe is one big engine swapping momentum from dark matter to light in one huge oscillation - big bang to infinity is only one half of it).
not rated yet Oct 04, 2017
Universe is not just expanding - it is better to say its folding - so no issue with linking to quantum mechanics as overall the universe is timeless - it likely has gone through many oscillations before and will again - not everyone producing life - we just happen to be in one of them that has all the folds in the right place/combination for consiousness to evolve.
Oct 04, 2017
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