Posted on Sep 13, 2019 in Astronomy, Dark Energy, Physics, Science, Space
In an interview with The Atlantic, Nobel-Prize winning physicist Adam Riess said: “I have absolutely no clue what dark energy is. Dark energy appears strong enough to push the entire universe – yet its source is unknown, its location is unknown and its physics are highly speculative.”
“There’s unknown physics going on in the early universe that we need to study, if the tension is real,” said Inh Jee, a cosmologist at the Max Plank Institute about signs of “tension” in understanding the rate of expansion of the universe —known as the “Hubble constant”—since the Big Bang, a central part of the quest to discover the origins of the universe, with astrophysicists believing they are getting closer and closer to the exact speed.
“The discovery of dark energy has greatly changed how we think about the laws of nature,” said Edward Witten, one of the world’s leading theoretical physicist at the Institute for Advanced Study in Princeton, N.J. who was not part of a new study gauging the universe’s accelerating growth and has been compared to Newton and Einstein.
In 1998, two teams of researchers found that the rate of expansion accelerated with distance, and that the universe was filled with mysterious “dark energy” that has caused the acceleration for 14 billion years—earning them a 2011 Nobel prize.
In Search of Dark Energy –Probing 11-Billion Years of Cosmic History
In a March 2, 2019 post, Dark Energy –“New Exotic Matter or ET Force Field?” The Daily Galaxy described a new, controversial theory suggesting that this dark energy might be getting stronger and denser, leading to a future in which atoms are torn asunder and time ends.
Hubble Unveils a Mystery -New Physics Needed to Explain Forces That Shaped the Cosmos
“Long, long ago, when the universe was only about 100,000 years old — a buzzing, expanding mass of particles and radiation — a strange new energy field switched on,” writes Dennis Overbye for New York Times Science. “That energy suffused space with a kind of cosmic antigravity, delivering a not-so-gentle boost to the expansion of the universe.”
Hubble Tension
Then, after another 100,000 years or so, the new field simply switched off, leaving no trace other than a speeded-up universe says a team of astronomers from Johns Hopkins University led by Adam Riess, a Bloomberg Distinguished Professor and Nobel laureate who is an expert in the Hubble constant. In a bold and speculative leap into the past, the team has posited the existence of this field to explain a baffling astronomical puzzle: the universe seems to be expanding faster than it should be.
“A growing mystery about the universe, known as the ‘Hubble Tension,’ is that it appears to be expanding much faster now than predicted even with our latest understanding of its initial conditions and contents,” says Riess. Their research is the first to provide a possible explanation—that the early universe received an infusion of dark energy soon after the Big Bang giving it a boost—which better matches all observations. This theory shows how this ‘tension’ may actually be revealing a new feature of the universe. It also makes predictions which can be tested so that more measurements should tell us if it is correct.”
Elephant in the Cosmos –Massive Gravity Replaces Dark Energy
A new study, written by researchers at the Max Planck Institute of Astrophysics in Germany and other universities, describes a new method of gauging the universe’s accelerating growth, putting the rate of expansion at 82.4 kilometers per second per megaparsec, higher than previous calculations—though it does admit to a 10 percent margin of error, meaning it could as low as 74 or as high as 90. Scientists say the differences between various methods are not miscalculations, but could be signs of “tension” in understanding of how the Big Bang Theory explains the cosmos.
Scientists have known for decades that the universe is expanding, but research in the past few years has shaken up calculations on the speed of growth—raising tricky questions about theories of the cosmos. The rate of expansion—the “Hubble constant”—is a central part of the quest to discover the origins of the universe, with astrophysicists believing they are getting closer and closer to the exact speed.
The unit of measurement for the Hubble constant, reports space and science reporter, Ivan Couronne for AFP, is kilometers per second per megaparsec—which is three million light-years. According to two different methods, the rate of expansion is either 67.4—or 73. The various measurement methods mean that galaxies three million light-years away (one megaparsec) would recede by either 67, 73… or perhaps 82 kilometers per second.
The new calculation is based on how light bends around large galaxies. Co-author Jee said the study’s large margin of error cannot help fine-tune the Hubble constant, but that its method adds to the debate over whether there are fundamental problems in cosmological theory.
Adam Riess,told AFP by email that Thursday’s study did not have precise enough results to help solve the continuing controversy. “I don’t think this adds much to the present state of affairs. Still it’s nice to see people look for alternative methods, so props (respect) for that,” he said.
Quintessence
One highly speculative conjecture The Galaxy reported on August 19, 2019, is an idea for the mechanism of an accelerating cosmic expansion called quintessence, a relative of the Higgs field that permeates the cosmos. Perhaps some clever life 5 billion years ago figured out how to activate that field, speculates astrophysicist Caleb Scharf in Nautil.us. How? “Beats me,” he says, “but it’s a thought-provoking idea, and it echoes some of the thinking of cosmologist Freeman Dyson’s famous 1979 paper Time Without End,” where he looked at life’s ability in the far, far future to act on an astrophysical scale in an open universe that need not evolve into a state of permanent quiescence. Where life and communication can continue for ever.
“Quirk in the Cosmos?” –‘Alpha Factor’ has Profound Implications for Physics and Life
“Perhaps hyper-advanced life isn’t just external. Perhaps it’s already all around. It is embedded in what we perceive to be physics itself, from the root behavior of particles and fields to the phenomena of complexity and emergence,” says Scharf, a research scientist at Columbia University and director of the Columbia Astrobiology Center. “What we think might be the effects of mysterious forces such as dark energy and dark matter in the Universe, could actually be the influence of alien intelligence – or maybe even aliens themselves.”
The Daily Galaxy, Sam Cabot, via AFP, John Hopkins University, and University College London
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