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Arthur T Knackerbracket has found the following story:
The accelerating expansion of the Universe may not be real, but could just be an apparent effect, according to new research published in the journal Monthly Notices of the Royal Astronomical Society. The new study—by a group at the University of Canterbury in Christchurch, New Zealand—finds the fit of Type Ia supernovae to a model universe with no dark energy to be very slightly better than the fit to the standard dark energy model.
Dark energy is usually assumed to form roughly 70% of the present material content of the Universe. However, this mysterious quantity is essentially a place-holder for unknown physics.
Current models of the Universe require this dark energy term to explain the observed acceleration in the rate at which the Universe is expanding. Scientists base this conclusion on measurements of the distances to supernova explosions in distant galaxies, which appear to be farther away than they should be if the Universe's expansion were not accelerating.
However, just how statistically significant this signature of cosmic acceleration is has been hotly debated in the past year. The previous debate pitted the standard Lambda Cold Dark Matter (ΛCDM) cosmology against an empty universe whose expansion neither accelerates nor decelerates. Both of these models though assume a simplified 100 year old cosmic expansion law -- Friedmann's equation.
Reference: Lawrence H. Dam, Asta Heinesen, David L. Wiltshire. Apparent cosmic acceleration from Type Ia supernovae. Monthly Notices of the Royal Astronomical Society, 2017; 472 (1): 835 DOI: 10.1093/mnras/stx1858
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(Score: 2, Insightful) by Anonymous Coward on Sunday September 17 2017, @08:08PM (5 children)
"Dark energy is usually assumed to form roughly 70% of the present material content of the Universe. However, this mysterious quantity is essentially a place-holder for unknown physics."
Bingo. Dark Matter/Energy might as well be invisible rainbow ponies or empty flying spaghetti bowls.
Helluva way to say, "We've no clue, so we made this up."
(Score: 2) by Gaaark on Monday September 18 2017, @02:00AM
Insightfully insightful!
Glad they are finally admitting it.
--- Please remind me if I haven't been civil to you: I'm channeling MDC. ---Gaaark 2.0 ---
(Score: 0) by Anonymous Coward on Monday September 18 2017, @03:15AM
Yes. The "unknown physics" could even be a rather boring artifact of their data analysis method. The light-curve fitting that is necessary to derive supernova intensity is only thinly justified. It wouldn't be surprising if the dark energy signal is really due to ancient novae acting differently from recent ones.
(Score: 2) by PiMuNu on Monday September 18 2017, @09:56AM (1 child)
> "However, this mysterious quantity is essentially a place-holder for unknown physics"
> ...
> Helluva way to say, "We've no clue, so we made this up."
I agree with this statement; but only in the context that ALL of physics is "made up"; we choose the best model for the data, which is still Dark Energy (and Dark Matter).
I think you are using the wrong emphasis on things. In physics, we make a model that best fits the available data. The accelerating universe model best fits the available data on the cosmological scale. On the microscopic scale, we have no available interpretation for dark energy; but we can't probe scales appropriate to make any useful statement about anything to do with gravity. Put another way, gravity is such a weak force that we have no way to measure it in particle colliders.
(Score: 1) by khallow on Monday September 18 2017, @12:04PM
And the stretching of space-time due to alleged dark energy is many orders of magnitude smaller than gravity. I seem to recall 120 orders of magnitude is claimed.
(Score: 1, Insightful) by Anonymous Coward on Monday September 18 2017, @04:36PM
Dark matter could be invisible rainbow ponies, but invisible elementary particles are the by far simpler theory, and therefore preferable (indeed, the existence of invisible rainbow ponies would imply the existence of invisible elementary particles, as that would be what invisible rainbow ponies would have to be made of).
Empty flying spaghetti bowls are out of the question as those would consist of baryonic matter, and thus would be visible, especially given that there is much more dark matter than ordinary matter.
Neither invisible rainbow ponies nor empty flying spaghetti bowls would have the right properties to explain dark energy.