New evidence: dark energy might not exist
The uncertainty of science: New evidence once again suggests that the assumptions that resulted in the invention of dark energy in the late 1990s might have been in error, and that dark energy simply might not exist.
New observations and analysis made by a team of astronomers at Yonsei University (Seoul, South Korea), together with their collaborators at Lyon University and KASI, show, however, that this key assumption is most likely in error. The team has performed very high-quality (signal-to-noise ratio ~175) spectroscopic observations to cover most of the reported nearby early-type host galaxies of SN Ia, from which they obtained the most direct and reliable measurements of population ages for these host galaxies. They find a significant correlation between SN luminosity and stellar population age at a 99.5% confidence level. As such, this is the most direct and stringent test ever made for the luminosity evolution of SN Ia. Since SN progenitors in host galaxies are getting younger with redshift (look-back time), this result inevitably indicates a serious systematic bias with redshift in SN cosmology. Taken at face values, the luminosity evolution of SN is significant enough to question the very existence of dark energy. When the luminosity evolution of SN is properly taken into account, the team found that the evidence for the existence of dark energy simply goes away.
…Other cosmological probes, such as CMB (Cosmic Microwave Background) and BAO (Baryonic Acoustic Oscillations), are also known to provide some indirect and “circumstantial” evidence for dark energy, but it was recently suggested that CMB from Planck mission no longer supports the concordance cosmological model which may require new physics. Some investigators have also shown that BAO and other low-redshift cosmological probes can be consistent with a non-accelerating universe without dark energy. In this respect, the present result showing the luminosity evolution mimicking dark energy in SN cosmology is crucial and is very timely.
There was also this story from early December, also raising questions about the existence of dark energy.
Bottom line: The data that suggested dark energy’s existence was always shallow with many assumptions and large margins of uncertainty. This research only underlines that fact, a fact that many cosmologists have frequently tried to sweep under the rug.
Dark energy still might exist, but it behooves scientists to look coldly at the data and always recognize its weaknesses. It appears in terms of dark energy the cosomological community is finally beginning to do so.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
The uncertainty of science: New evidence once again suggests that the assumptions that resulted in the invention of dark energy in the late 1990s might have been in error, and that dark energy simply might not exist.
New observations and analysis made by a team of astronomers at Yonsei University (Seoul, South Korea), together with their collaborators at Lyon University and KASI, show, however, that this key assumption is most likely in error. The team has performed very high-quality (signal-to-noise ratio ~175) spectroscopic observations to cover most of the reported nearby early-type host galaxies of SN Ia, from which they obtained the most direct and reliable measurements of population ages for these host galaxies. They find a significant correlation between SN luminosity and stellar population age at a 99.5% confidence level. As such, this is the most direct and stringent test ever made for the luminosity evolution of SN Ia. Since SN progenitors in host galaxies are getting younger with redshift (look-back time), this result inevitably indicates a serious systematic bias with redshift in SN cosmology. Taken at face values, the luminosity evolution of SN is significant enough to question the very existence of dark energy. When the luminosity evolution of SN is properly taken into account, the team found that the evidence for the existence of dark energy simply goes away.
…Other cosmological probes, such as CMB (Cosmic Microwave Background) and BAO (Baryonic Acoustic Oscillations), are also known to provide some indirect and “circumstantial” evidence for dark energy, but it was recently suggested that CMB from Planck mission no longer supports the concordance cosmological model which may require new physics. Some investigators have also shown that BAO and other low-redshift cosmological probes can be consistent with a non-accelerating universe without dark energy. In this respect, the present result showing the luminosity evolution mimicking dark energy in SN cosmology is crucial and is very timely.
There was also this story from early December, also raising questions about the existence of dark energy.
Bottom line: The data that suggested dark energy’s existence was always shallow with many assumptions and large margins of uncertainty. This research only underlines that fact, a fact that many cosmologists have frequently tried to sweep under the rug.
Dark energy still might exist, but it behooves scientists to look coldly at the data and always recognize its weaknesses. It appears in terms of dark energy the cosomological community is finally beginning to do so.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Sounds interesting for sure. I had indicated something to the effect of the underlying assumptions might be wrong.
The short is, theories at the edge of knowledge change over time. Consider Linus Pauling winning the Nobel prize in chemistry for his valence bond theory which is now supplanted by molecular orbital theory.
Dark matter too?
I have always believed we live in a closed universe. Recurring oscillations of expansion and contraction.
I remember reading about a string theory proposal that when two dimensions touched each other that was the point that a new ‘big bang’ happened.
But it never explained what would happen if the next touch(big bang) happened relatively close to another one.
If there have been other big bangs then we should see the evidence. Matter passing back through this area at least.
I can only agree Phill O,
As I’ve mentioned here before, dark matter/energy were originally only intended as place holders, and ended up as gospel truth.
When cosmologies find something they can’t explain, to decide on a theory that it must be due to something that is invisible and essentially undetectable seems like pretty poor explanations to me.
It’s heartening to know there are people that are actively working on different theories to explain what we believe to be anomalies in the standard model.
pzatchok–
I’d be interested in what you think of ‘Conformal Cyclic Cosmology,’ as proposed by Roger Penrose.
(one of the few theories that doesn’t violate the laws of thermodynamics)
“Aeons before the Big Bang”
Conformal Cyclic Cosmology
Dr. Roger Penrose (master of the overhead projector)
Copernicus Center Lecture November 2011
https://youtu.be/4YYWUIxGdl4
1:57:35
(starts at 5:26)
Wayne —
Although I understand that many in the field have problems with his interpretations of recent CMB radiation data, Dr. Penrose always gives very thought provoking lectures. And he is as you say master of the overhead.
I’ve been working my way (again) through his Cycles of Time – recommended if you haven’t read it. His ideas, while unorthodox, always seem to have enough plausibility to hold your interest and engagement.
Or maybe its simply his maverick refusal to ever accept the standard line that I admire. I could only wish that, at least occasionally, he would offer the same mathematical rigor for the mainstream audience that say Leonard Susskind routinely lectures with.
Physicsworld article on recent claims by Dr. Penrose and his team, with link to the source arXive post.
https://physicsworld.com/a/new-evidence-for-cyclic-universe-claimed-by-roger-penrose-and-colleagues/
A TED talk I just stumbled upon
The search for dark matter — and what we’ve found so far by Risa Wechsler.
https://www.ted.com/talks/risa_wechsler_the_search_for_dark_matter_and_what_we_ve_found_so_far
If this is one of the formost experts on the subject, then no wonder there is at least a little controversy… She gladly skips over so many unknowns, from the big bang onwards.
I counted 5 debatable points in the first 7 minutes.
( And unlike many videos on here, 1. It’s not proving my point, it’s a scientist, and I’m challenging you to find the mistakes, and 2. It’s only 15 minutes long!)
Sigh. The only dark matter is black holes. The only dark energy is the gravitational pull of those holes. “PRE”mordial black holes existed BEFORE the Big Bang and are the reason our “universe” formed galaxies so quickly. The true universe makes OUR universe a miniverse. Black holes merge, and merge, and merge, until, every septillion years or so, a “white hole” spits out enough recycled ordinary matter to form a new miniverse. Guthian inflation is the last gasp of our current ridiculously anthropocentric cosmology. One day soon, Guth and the superstringers will be on a dusty shelf with Ptolemy.
— A pessimist.