Featured Research

from universities, journals, and other organizations

Dark Fluid: Dark Matter And Dark Energy May Be Two Faces Of Same Coin

Date:
February 1, 2008
Source:
Science and Technology Facilities Council
Summary:
Astronomers believe they can "simplify the dark side of the universe" by shedding new light on two of its mysterious constituents. Only 4% of the universe is made of known material - the other 96% is traditionally labeled into two sectors, dark matter and dark energy. "Both dark matter and dark energy could be two faces of the same coin," according to an astrophysicist.

The magnificent spiral arms of the nearby galaxy Messier 81. Astronomers believe that both the universe and galaxies are held together by the gravitational attraction of a huge amount of unseen material, now commonly referred to as dark matter.
Credit: NASA/JPL/Caltech/Harvard-Smithsonian Center for Astrophysics

Astronomers at the University of St Andrews believe they can "simplify the dark side of the universe" by shedding new light on two of its mysterious constituents.

Dr HongSheng Zhao, of the University's School of Physics and Astronomy, has shown that the puzzling dark matter and its counterpart dark energy may be more closely linked than was previously thought.

Only 4% of the universe is made of known material - the other 96% is traditionally labelled into two sectors, dark matter and dark energy.

A British astrophysicist and Advanced Fellow of the UK's Science and Technology Facilities Council, Dr Zhao points out, "Both dark matter and dark energy could be two faces of the same coin.

"As astronomers gain understanding of the subtle effects of dark energy in galaxies in the future, we will solve the mystery of astronomical dark matter at the same time. "

Astronomers believe that both the universe and galaxies are held together by the gravitational attraction of a huge amount of unseen material, first noted by the Swiss astronomer Fritz Zwicky in 1933, and now commonly referred to as dark matter.

Dr Zhao reports that, "Dark energy has already revealed its presence by masking as dark matter 60 years ago if we accept that dark matter and dark energy are linked phenomena that share a common origin."

In Dr Zhao's model, dark energy and dark matter are simply different manifestations of the same thing, which he has considered as a 'dark fluid'. On the scale of galaxies, this dark fluid behaves like matter and on the scale of the Universe overall as dark energy, driving the expansion of the Universe. Importantly, his model, unlike some similar work, is detailed enough to produce the same 3:1 ratio of dark energy to dark matter as is predicted by cosmologists.

Efforts are currently underway to hunt for very massive dark-matter particles with a variety of experiments. The Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) in Geneva is a particle accelerator that amongst other objectives, could potentially detect dark matter particles.

According to Dr Zhao, these efforts could turn out to be fruitless. He said, "In this simpler picture of universe, the dark matter would be at a surprisingly low energy scale, too low to be probed by upcoming Large Hadron Collider.

"The search for dark-matter particles so far has concentrated on highly-energetic particles. If dark matter however is a twin phenomenon of dark energy, it will not show up at instruments like the LHC, but has been seen over and over again in galaxies by astronomers."

However, the Universe might be absent of dark-matter particles at all. The findings of Dr Zhao are also compatible with an interpretation of the dark component as a modification of the law of gravity rather than particles or energy.

Dr Zhao concluded. "No matter what dark matter and dark energy are, these two phenomena are likely not independent of each other."

Background

Theories of the physics of gravity were first developed by Isaac Newton in 1687 and refined by Albert Einstein’s theory of General Relativity in 1916 which stated that the speed of gravity is equal to the speed of light. However, Einstein was never fully decided on whether his equation should add an omnipresent constant source, now called dark energy in general.

Astronomers following Fred Zwicky have also speculated additional sources to Einstein's equation in the form of non-light emitting material, called dark matter in general. Apart from very light neutrinos neither dark sources have been confirmed experimentally.

Dr Zhao and his collaborators' findings have recently been published by Astrophysical Journal Letters in December 2007, and Physics Review D. 2007.


Story Source:

The above story is based on materials provided by Science and Technology Facilities Council. Note: Materials may be edited for content and length.


Cite This Page:

Science and Technology Facilities Council. "Dark Fluid: Dark Matter And Dark Energy May Be Two Faces Of Same Coin." ScienceDaily. ScienceDaily, 1 February 2008. <www.sciencedaily.com/releases/2008/01/080131094056.htm>.
Science and Technology Facilities Council. (2008, February 1). Dark Fluid: Dark Matter And Dark Energy May Be Two Faces Of Same Coin. ScienceDaily. Retrieved September 18, 2014 from www.sciencedaily.com/releases/2008/01/080131094056.htm
Science and Technology Facilities Council. "Dark Fluid: Dark Matter And Dark Energy May Be Two Faces Of Same Coin." ScienceDaily. www.sciencedaily.com/releases/2008/01/080131094056.htm (accessed September 18, 2014).

Share This



More Space & Time News

Thursday, September 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Boeing, SpaceX to Send Astronauts to Space Station

Boeing, SpaceX to Send Astronauts to Space Station

AFP (Sep. 17, 2014) — NASA selected Boeing and SpaceX on Tuesday to build America's next spacecraft to carry astronauts to the International Space Station (ISS) by 2017, opening the way to a new chapter in human spaceflight. Duration: 01:13 Video provided by AFP
Powered by NewsLook.com
East Coast Treated To Rare Meteor Sighting

East Coast Treated To Rare Meteor Sighting

Newsy (Sep. 16, 2014) — Numerous residents along the East Coast reported seeing a bright meteor flash through the sky Sunday night. Video provided by Newsy
Powered by NewsLook.com
Space Race Pits Bezos Vs Musk

Space Race Pits Bezos Vs Musk

Reuters - Business Video Online (Sep. 16, 2014) — Amazon CEO Jeff Bezos' startup will team up with Boeing and Lockheed to develop rocket engines as Elon Musk races to have his rockets certified. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
NASA Picks Boeing and SpaceX to Ferry Astronauts

NASA Picks Boeing and SpaceX to Ferry Astronauts

AP (Sep. 16, 2014) — NASA is a giant step closer to launching Americans again from U.S. soil. It has announced it has picked Boeing and SpaceX to transport astronauts to the International Space Station in the next few years. (Sept. 16) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins