Featured Research

from universities, journals, and other organizations

White dwarf star throws light on possible variability of a constant of Nature

Date:
July 4, 2013
Source:
University of New South Wales
Summary:
Astronomers have studied a distant star where gravity is more than 30,000 times greater than on Earth to test the controversial theory that one of the constants of Nature is not a constant. The researchers used the Hubble Space Telescope to measure the strength of the electromagnetic force -- known as alpha -- on a white dwarf star. The results do not contradict the variable-constant theory.

Researchers have studied a distant star where gravity is more than 30,000 times greater than on Earth to test the controversial theory that one of the constants of Nature -- the strength of the electromagnetic force, known as alpha -- is not a constant.
Credit: UNSW

An international team led by the University of New South Wales has studied a distant star where gravity is more than 30,000 times greater than on Earth to test its controversial theory that one of the constants of Nature is not a constant.

Dr Julian Berengut and his colleagues used the Hubble Space Telescope to measure the strength of the electromagnetic force -- known as alpha -- on a white dwarf star.

Their results, which do not contradict the variable constant theory, are to be published in the journal Physical Review Letters. Dr Berengut, of the UNSW School of Physics, said the team's previous research on light from distant quasars suggests that alpha -- known as the fine-structure constant -- may vary across the universe.

"This idea that the laws of physics are different in different places in the cosmos is a huge claim, and needs to be backed up with solid evidence," he says.

"A white dwarf star was chosen for our study because it has been predicted that exotic, scalar energy fields could significant alter alpha in places where gravity is very strong."

"Scalar fields are forms of energy that often appear in theories of physics that seek to combine the Standard Model of particle physics with Einstein's general theory of relativity."

"By measuring the value of alpha near the white dwarf and comparing it with its value here and now in the laboratory we can indirectly probe whether these alpha-changing scalar fields actually exist."

White dwarfs are very dense stars near the ends of their lives. The researchers studied the light absorbed by nickel and iron ions in the atmosphere of a white dwarf called G191-B2B. The ions are kept above the surface by the star's strong radiation, despite the pull of its extremely strong gravitational field.

"This absorption spectrum allows us to determine the value of alpha with high accuracy. We found that any difference between the value of alpha in the strong gravitational field of the white dwarf and its value on Earth must be smaller than one part in ten thousand," Dr Berengut says.

"This means any scalar fields present in the star's atmosphere must only weakly affect the electromagnetic force." Dr Berengut said that more precise measurements of the iron and nickel ions on earth are needed to complement the high-precision astronomical data.

"Then we should be able to measure any change in alpha down to one part per million. That would help determine whether alpha is a true constant of Nature, or not."


Story Source:

The above story is based on materials provided by University of New South Wales. Note: Materials may be edited for content and length.


Journal Reference:

  1. J. C. Berengut, V. V. Flambaum, A. Ong, J. K. Webb, John D. Barrow, M. A. Barstow, S. P. Preval, J. B. Holberg. Limits on the Dependence of the Fine-Structure Constant on Gravitational Potential from White-Dwarf Spectra. Phys. Rev. Lett., 2013 DOI: 10.1103/PhysRevLett.111.010801

Cite This Page:

University of New South Wales. "White dwarf star throws light on possible variability of a constant of Nature." ScienceDaily. ScienceDaily, 4 July 2013. <www.sciencedaily.com/releases/2013/07/130704095042.htm>.
University of New South Wales. (2013, July 4). White dwarf star throws light on possible variability of a constant of Nature. ScienceDaily. Retrieved October 2, 2014 from www.sciencedaily.com/releases/2013/07/130704095042.htm
University of New South Wales. "White dwarf star throws light on possible variability of a constant of Nature." ScienceDaily. www.sciencedaily.com/releases/2013/07/130704095042.htm (accessed October 2, 2014).

Share This



More Space & Time News

Thursday, October 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Astronomers Spot Largest, Brightest Solar Flare Ever

Astronomers Spot Largest, Brightest Solar Flare Ever

Newsy (Oct. 1, 2014) — The initial blast from the record-setting explosion would have appeared more than 10,000 times more powerful than any flare ever recorded. Video provided by Newsy
Powered by NewsLook.com
French Apple Fans Discover the Apple Watch

French Apple Fans Discover the Apple Watch

AFP (Sep. 30, 2014) — Apple fans in France discover the latest toy, the Apple Watch. The watch comes in two sizes and an array of interchangeable, fashionable wrist straps. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com
The Water You Drink Might Be Older Than The Sun

The Water You Drink Might Be Older Than The Sun

Newsy (Sep. 27, 2014) — Researchers at the University of Michigan simulated the birth of planets and our sun to determine whether water in the solar system predates the sun. Video provided by Newsy
Powered by NewsLook.com
First Woman Cosmonaut in 17 Years Blasts Off for ISS

First Woman Cosmonaut in 17 Years Blasts Off for ISS

AFP (Sep. 26, 2014) — A Russian Soyuz spacecraft carrying an American astronaut and two Russian cosmonauts, including the first woman cosmonaut in 17 years, blasted off on schedule Friday. Duration: 00:35 Video provided by AFP
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:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

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