Subscribe to our free daily newsletters
. 24/7 Space News .




Subscribe to our free daily newsletters



STELLAR CHEMISTRY
Astronomers reveal evidence of dynamical dark energy
by Staff Writers
Portsmouth, UK (SPX) Oct 06, 2017


The cosmological "constant" (illustrated by the straight yellow line) is introduced to explain the accelerated expansion of the Universe (shown as the expanding blue cone) due to the presence of dark energy. The study instead suggests that the contribution of dark energy to this expansion is time-dependent (grey curve). The uncertainty of this time dependency is also shown (blue shaded area). Image courtesy Gong-Bo Zhao, NAOC and the University of Portsmouth.

An international research team, including astronomers from the University of Portsmouth, has revealed evidence of dynamical dark energy. The discovery, recently published in the journal Nature Astronomy, found that the nature of dark energy may not be the cosmological constant introduced by Albert Einstein 100 years ago, which is crucial for the study of dark energy.

Lead author of the study Professor Gong-Bo Zhao, from the Institute of Cosmology and Gravitation (ICG) at the University of Portsmouth and the National Astronomical Observatories of China (NAOC), said: "We are excited to see that current observations are able to probe the dynamics of dark energy at this level, and we hope that future observations will confirm what we see today."

Co-author Professor Bob Nichol, Director of the ICG, said: "Since its discovery at the end of last century, dark energy has been a riddle wrapped in an enigma. We are all desperate to gain some greater insight into its characteristics and origin. Such work helps us make progress in solving this 21st Century mystery."

Revealing the nature of dark energy is one of key goals of modern sciences. The physical property of dark energy is represented by its Equation of State (EoS), which is the ratio of pressure and energy density of dark energy.

In the traditional Lambda-Cold Dark Matter (LCDM) model, dark energy is essentially the cosmological constant, i.e., the vacuum energy, with a constant EoS of -1. In this model, dark energy has no dynamical features.

In 2016, a team within the SDSS-III (BOSS) collaboration led by Professor Zhao performed a successful measurement of the Baryonic Acoustic Oscillations (BAO) at multiple cosmic epochs with a high precision.

Based on this measurement and a method developed by Professor Zhao for dark energy studies, the team found an evidence of dynamical dark energy at a significance level of 3.5 sigma. This suggests that the nature of dark energy may not be the vacuum energy, but some kind of dynamical field, especially for the quintom model of dark energy whose EoS varies with time and crosses the -1 boundary during evolution, according to NAOC.

The dynamics of dark energy needs to be confirmed by next-generation astronomical surveys. The team points to the upcoming Dark Energy Spectroscopic Instrument (DESI) survey, which aims to begin creating a 3D cosmic map in 2018.

In the next five to ten years, the world largest galaxy surveys will provide observables which may be key to unveil the mystery of dark energy.

The new study was supported by the National Natural Science Foundation of China (NSFC), Chinese Academy of Sciences and a Royal Society Newton Advanced Fellowship.

Professor Nichol added: "This work is the culmination of many years of work in collaboration between scientists in China and the UK. Gong-Bo is one of our brightest stars holding a joint position between NAOC and here at the ICG."

Research paper

STELLAR CHEMISTRY
New supernova analysis reframes dark energy debate
London, UK (SPX) Sep 27, 2017
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 ... read more

Related Links
University of Portsmouth
Stellar Chemistry, The Universe And All Within It


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only

Comment using your Disqus, Facebook, Google or Twitter login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

STELLAR CHEMISTRY
Alaska antenna to improve NASA's space communications system

USNO Astronomers Measure New Distances To Nearby Stars

NASA May Extend BEAM's Time on the International Space Station

OECD calls for tourism to be more sustainable

STELLAR CHEMISTRY
Arianespace to launch COSMO-SkyMed satellites manufactured by Thales

New Zealand opens first rocket launch site

Launch Vehicle and Missile Ascent Trajectories

Ariane 5 rocket puts satellites into orbit on second attempt

STELLAR CHEMISTRY
Lockheed Martin Reveals New Details to its Mars Base Camp Vision

Fresh Look at Old Data Yields Surprise Near Martian Equator

Methane belches kept water flowing on ancient Mars

Another Chance to Put Your Name on Mars

STELLAR CHEMISTRY
UN official commends China's role in space cooperation

Mars probe to carry 13 types of payload on 2020 mission

China's cargo spacecraft separates from Tiangong-2 space lab

Work on China's mission to Mars 'well underway'

STELLAR CHEMISTRY
L-Band Satellite Operators Need To Reposition

GomSpace and Luxembourg to develop space activities in the Grand Duchy

Spacepath Communications Acquires Tango Wave

Brodeur Partners Launches Entrepreneurial Space Group

STELLAR CHEMISTRY
Sputnik, the tiny sphere that launched the space race

New laser sensor could detect explosives, dangerous gases more quickly

Germany-based Hensoldt acquires Kelvin Hughes

UV-irradiated amorphous ice behaves like liquid at low temperatures

STELLAR CHEMISTRY
MATISSE to Shed Light on the Formation of Earth and Planets

Glenn Tests Thruster Bound for Metal World

Searching for Distant Worlds With a Flying Telescope

Scientists propose new concept of terrestrial planet formation

STELLAR CHEMISTRY
Helicopter test for Jupiter icy moons radar

Solving the Mystery of Pluto's Giant Blades of Ice

Global Aerospace Corporation to present Pluto lander concept to NASA

Pluto features given first official names




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News






The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement