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7310 |
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Date: July 24, 2023 at 08:33:30
From: akira, [DNS_Address]
Subject: New research puts age of universe at 26.7 billion years... |
URL: https://phys.org/news/2023-07-age-universe-billion-years-previously.html |
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for the moment, anyways
excerpt
"Our universe could be twice as old as current estimates, according to a new
study that challenges the dominant cosmological model and sheds new light
on the so-called "impossible early galaxy problem."
The work is published in the journal Monthly Notices of the Royal
Astronomical Society.
"Our newly-devised model stretches the galaxy formation time by a several
billion years, making the universe 26.7 billion years old, and not 13.7 as
previously estimated," says author Rajendra Gupta, adjunct professor of
physics in the Faculty of Science at the University of Ottawa.
For years, astronomers and physicists have calculated the age of our
universe by measuring the time elapsed since the Big Bang and by studying
the oldest stars based on the redshift of light coming from distant galaxies. In
2021, thanks to new techniques and advances in technology, the age of our
universe was thus estimated at 13.797 billion years using the Lambda-CDM
concordance model.
However, many scientists have been puzzled by the existence of stars like
the Methuselah that appear to be older than the estimated age of our
universe and by the discovery of early galaxies in an advanced state of
evolution made possible by the James Webb Space Telescope. These
galaxies, existing a mere 300 million years or so after the Big Bang, appear to
have a level of maturity and mass typically associated with billions of years of
cosmic evolution. Furthermore, they're surprisingly small in size, adding
another layer of mystery to the equation.
Zwicky's tired light theory proposes that the redshift of light from distant
galaxies is due to the gradual loss of energy by photons over vast cosmic
distances. However, it was seen to conflict with observations. Yet Gupta
found that "by allowing this theory to coexist with the expanding universe, it
becomes possible to reinterpret the redshift as a hybrid phenomenon, rather
than purely due to expansion."
In addition to Zwicky's tired light theory, Gupta introduces the idea of
evolving "coupling constants," as hypothesized by Paul Dirac. Coupling
constants are fundamental physical constants that govern the interactions
between particles. According to Dirac, these constants might have varied
over time. By allowing them to evolve, the timeframe for the formation of
early galaxies observed by the Webb telescope at high redshifts can be
extended from a few hundred million years to several billion years. This
provides a more feasible explanation for the advanced level of development
and mass observed in these ancient galaxies.
Moreover, Gupta suggests that the traditional interpretation of the
"cosmological constant," which represents dark energy responsible for the
accelerating expansion of the universe, needs revision. Instead, he proposes
a constant that accounts for the evolution of the coupling constants. This
modification in the cosmological model helps address the puzzle of small
galaxy sizes observed in the early universe, allowing for more accurate
observations."
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Responses:
[7313] [7311] [7319] [7318] [7312] |
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7313 |
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Date: July 25, 2023 at 04:20:15
From: akira, [DNS_Address]
Subject: some scientists disagree... |
URL: https://www.iflscience.com/why-its-extremely-unlikely-the-universe-is-267-billion-years-old-69904 |
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E AND PHYSICS
space
ASTRONOMY
Why It's Extremely Unlikely The Universe Is 26.7 Billion Years Old
A new claim has attracted a lot of media, but other scientists say it’s up
against a mountain of competing evidence.
STEPHEN LUNTZ, July 20, 2023
Some of the galaxies in this deep field are almost as old as the universe, but
they don't requre the universe to be twice as old as we have thought
Some of the galaxies in this deep field are almost as old as the universe, but
they don't require the universe to be twice as old as we have thought.
One cosmologist has claimed the universe is almost twice as old as
conventional estimates, and his claims have attracted plenty of attention.
The proposition would upend not just the timing of everything, but a great
deal of what we think we know about the universe’s development. However,
he’s not even close to convincing his peers.
The standard estimate for the age of the universe is 13.79 billion years, plus
or minus 20 million years. Some recent observations appear to contradict
this. In most cases there are alternative explanations, but many astronomers
do consider it plausible the true value may be a little higher, either at the
upper end of the error bars, or a little bit beyond that.
Dr Rajendra Gupta of the University of Ottawa, however, has thrown such
considerations out and published a paper arguing the true age of the
universe is 26.7 billion years. He calculates this using a hybrid version of an
old hypothesis known as “tired light” that is generally regarded as
discredited, and modern cosmology. Quite a few media outlets have jumped
on board, mostly treating the claim as if it’s as plausible as any other peer-
reviewed paper.
A much older universe would certainly explain some things, like how some of
the galaxies the JWST has spotted could be so developed so soon after we
think things began. However, Carl Sagan’s aphorism that “extraordinary
claims require extraordinary proof” seems made for this circumstance, and
according to other professional astronomers, Gupta has no proof at all.
“There are many, many measurements that suggest the age of the universe
is about 14 billion years,” Professor Tamara Davis of the University of
Queensland told IFLScience. “Not just the cosmic microwave background,
not just the expansion rate measured using supernovas, there’s also the
large-scale structure of the universe and the measured age of the oldest
stars.” At one point these appeared to be in conflict, Davis explained, with
some pointing to a universe 9-10 billion years old, while others suggested 14
billion years. Now, with some reconsideration, all approximately agree.
“The other issue is that they’ve fitted their model to the supernova data
alone,” Davis continued. “It’s just not good enough to fit it to one set of data
and ignore all the rest.” She compared this to previous attempts to use
supernova data to discredit dark energy, without testing the consequences.
“They don’t seem to have done even simple things like see whether their new
theory of gravity breaks what we know about the orbits of planets in the solar
system,” she added.
Dr Brad Tucker of the Australian National University made similar criticisms to
Davis, adding that if the tired light phenomenon existed, "it would have either
been noticed or calibrated for" previously.
Gupta makes much of the earliest galaxies the JWST has spotted, which did
indeed cause some puzzlement among astronomers. However, Davis told
IFLScience this has partially been explained. “There were difficulties with
calibration with the JWST that have now been fixed,” she said. The distance
to these galaxies, and therefore their age, was estimated using the relative
brightness of different parts of the spectrum. As astronomers have become
more familiar with the instrument, they’ve refined their estimates to get
figures more consistent with a 14 billion-year-old universe for most of them.
Even one study that Gupta refers to, which found surprisingly developed
galaxies at very large distances in the JWST data, indicates these galaxies
are very young, Davis added, and would at most nudge our estimates of the
universe’s age slightly higher.
The oldest known star in the Milky Way, HD 140283, also known as the
Methuselah star, has been estimated to be 14.46 billion years old, with an
error of 800 million years. However, while there are no questions HD 140283
is old, subsequent estimates have been low enough to avoid any conflict with
the universe’s age. Moreover, even if the highest estimate is right, it might
add 1-2 billion years to estimates of the universe’s age, not a doubling.
Similarly, a recent study places the age of the oldest known globular star
cluster uncomfortably close to the 13.8 billion-year ceiling. If the universe
was anything like the age Gupta suggests, however, we’d expect to see
clusters that were 20 billion years old at least, and nothing like that has been
found.
Gupta’s paper is published in the Monthly Notices of the Royal Astronomical
Society.
This article was amended to include a comment from Dr Brad Tucker.
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7311 |
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Date: July 24, 2023 at 16:03:24
From: Jeff/Lake Almanor,CA, [DNS_Address]
Subject: They will one day, find that it's infinite...........................) |
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That will include the future........................................................................>
Thank God, will be understood..................................................................>
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Responses:
[7319] [7318] [7312] |
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7319 |
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Date: August 14, 2023 at 23:08:51
From: ryan, [DNS_Address]
Subject: Re: They will one day, find that it's... |
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unfortunately,it's one more thing mankind could fuck up...
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Responses:
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7318 |
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Date: August 09, 2023 at 20:45:41
From: kay.so.or, [DNS_Address]
Subject: Re: They will one day, find that it's... |
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yessss....humans just keep explaining things
away...somethings arent explainable, or able for us to
understand with our pea brains....🤷♀️🤔😶🌫️
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7312 |
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Date: July 24, 2023 at 18:28:55
From: akira, [DNS_Address]
Subject: I wouldn't be surprised |
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the future & past are an illusion anyway :)
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Responses:
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