Nav: Home

Centenary of cosmological constant lambda

July 11, 2018

Physicists are now celebrating the 100th anniversary of the cosmological constant. On this occasion, two papers recently published in EPJ H highlight its role in modern physics and cosmology. Although the term was first introduced when the universe was thought to be static, today the cosmological constant has become the main candidate for representing the physical essence believed to be responsible for the accelerated expansion of our universe. Before becoming widely accepted, the cosmological constant was during decades the subject of many discussions about its necessity, its value and its physical essence. Today, there are still unresolved problems in understanding the deep physical nature of the phenomena associated with the cosmological constant.

In his paper, Bohdan Novosyadlyj, affiliated with the National University of Lviv, Ukraine, explains how Albert Einstein introduced the cosmological constant in 1917 to make the model of static Universe, then accepted by most scientists, work. Its deep physical meaning, however, escaped Einstein. Following the discovery of evidence for a non-static universe in 1929, Einstein regretted introducing this constant into equations of general relativity. Meanwhile, other scientists tried for decades to understand its physical meaning and establish its magnitude. When evidence of dark energy was observed by Michael Turner in 1998, scientists began to consider alternatives of cosmological constant to model that dark energy.

In another paper, Cormac O'Raifeartaigh from Waterford Institute of Technology, Ireland, and colleagues present a detailed analysis of the 100-year history of the cosmological constant. Starting with static models of the universe, the paper explains how the constant became marginalised following the discovery of cosmic expansion. Subsequently, it was revived to address specific cosmic puzzles such as the timespan of expansion, the formation of galaxies and the red-shifts of quasars.

More recently, the constant has acquired greater physical meaning, as it has helped to the matching of further recent observations with theory. Specifically, it was helpful to reconcile current theory with the recently-observed phenomenon of dark energy as evidenced by the measurement of present cosmic expansion using the Hubble Space Telescope, the measurement of past expansion using supernova, and the measurement of cosmic microwave background by balloon and satellite.
-end-
References: "Century of Λ" by B. Novosyadlyj (2018), European Physical Journal H, DOI 10.1140/epjh/e2018-90007-y

"One hundred years of the cosmological constant: from 'superfluous stunt' to dark energy" by C. O'Raifeartaigh, M. O'Keeffe, W. Nahm, and S. Mitton (2018), European Physical Journal H, DOI 10.1140/epjh/e2017-80061-7

Springer

Related Dark Energy Articles:

Origin of Milky Way's hypothetical dark matter signal may not be so dark
A mysterious gamma-ray glow at the center of the Milky Way is most likely caused by pulsars.
Explaining the accelerating expansion of the universe without dark energy
Enigmatic dark energy, thought to make up 68 percent of the universe, may not exist at all, according to a Hungarian-American team.
Wave energy researchers dive deep to advance clean energy source
One of the biggest untapped clean energy sources on the planet -- wave energy -- could one day power millions of homes across the US.
Dark energy measured with record-breaking map of 1.2 million galaxies
A team of hundreds of physicists and astronomers, including those from Berkeley Lab, have announced results from the largest-ever, three-dimensional map of distant galaxies.
Astronomers map a record-breaking 1.2 million galaxies to study the secrets of dark energy
Astronomers announced this week the sharpest results yet on the properties of dark energy.
Accelerating research into dark energy
A quick method for making accurate, virtual universes to help understand the effects of dark matter and dark energy has been developed by UCL and CEFCA scientists.
MIT Energy Initiative welcomes Exelon as member for clean energy research
MIT Energy Initiative announces that national energy provider Exelon joins MITEI as a member to focus research support through MITEI's Low-Carbon Energy Centers.
ASU professor honored for work on energy and social aspects of energy policy
Martin 'Mike' Pasqualetti, an Arizona State University professor and an expert on energy and social components of energy development, will be awarded 2015 Alexander and Ilse Melamid Memorial Medal by the American Geographical Society.
DESI, an ambitious probe of dark energy, achieves its next major milestone
The US Department of Energy has announced approval of Critical Decision 2 (CD-2), authorizing the scientific scope, schedule, and funding profile of DESI, the Dark Energy Spectroscopic Instrument, an exceptional apparatus designed to improve our understanding of the role of dark energy in the expansion history of the universe.
Searching for ingredients of dark matter and dark energy
Two new reports advance efforts to identify components of dark matter and energy, which together comprise about 95 percent of the universe yet leave much to scientists' imaginations.

Related Dark Energy Reading:

Dark Energy: Theory and Observations
by Luca Amendola (Author), Shinji Tsujikawa (Author)

Dark Energy
by Robison Wells (Author)

How to Manifest with Dark Energy: Beyond the Law of Attraction and The Secret
by Dark Realm Publishing

Dark Side of the Universe: Dark Matter, Dark Energy, and the Fate of the Cosmos
by Iain Nicolson (Author)

We Have No Idea: A Guide to the Unknown Universe
by Jorge Cham (Author), Daniel Whiteson (Author)

Dark Energy
by Yun Wang (Author)

The 4 Percent Universe: Dark Matter, Dark Energy, and the Race to Discover the Rest of Reality
by Richard Panek (Author)

The Extravagant Universe: Exploding Stars, Dark Energy, and the Accelerating Cosmos (Princeton Science Library)
by Robert P. Kirshner (Author), Robert P. Kirshner (Epilogue)

Dark Energy
by Mr. Bren A Stockdale (Author)

Dark Energy (Peking University-World Scientific Advance Physics Series)
by WSPC

Best Science Podcasts 2018

We have hand picked the best science podcasts for 2018. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Dying Well
Is there a way to talk about death candidly, without fear ... and even with humor? How can we best prepare for it with those we love? This hour, TED speakers explore the beauty of life ... and death. Guests include lawyer Jason Rosenthal, humorist Emily Levine, banker and travel blogger Michelle Knox, mortician Caitlin Doughty, and entrepreneur Lux Narayan.
Now Playing: Science for the People

#491 Frankenstein LIVES
Two hundred years ago, Mary Shelley gave us a legendary monster, shaping science fiction for good. Thanks to her, the name of Frankenstein is now famous world-wide. But who was the real monster here? The creation? Or the scientist that put him together? Tune in to a live show from Dragon Con 2018 in Atlanta, as we breakdown the science of Frankenstein, complete with grave robbing and rivers of maggots. Featuring Tina Saey, Lucas Hernandez, Travor Valle, and Nancy Miorelli. Moderated by our own Bethany Brookshire. Related links: Scientists successfully transplant lab-grown lungs into pigs, by Maria Temming on Science...