Featured Research

from universities, journals, and other organizations

Speed of light may not be fixed, scientists suggest; Ephemeral vacuum particles induce speed-of-light fluctuations

Date:
March 25, 2013
Source:
Springer
Summary:
Two new articles challenge established wisdom about the nature of vacuum. In one article scientists have identified a quantum level mechanism for interpreting vacuum as being filled with pairs of virtual particles with fluctuating energy values. As a result, the inherent characteristics of vacuum, like the speed of light, may not be a constant after all, but fluctuate.

Illustration: Ephemeral vacuum particles induce speed-of-light fluctuations.
Credit: Image courtesy of Springer

Two forthcoming European Physical Journal D papers challenge established wisdom about the nature of vacuum. In one paper, Marcel Urban from the University of Paris-Sud, located in Orsay, France and his colleagues identified a quantum level mechanism for interpreting vacuum as being filled with pairs of virtual particles with fluctuating energy values. As a result, the inherent characteristics of vacuum, like the speed of light, may not be a constant after all, but fluctuate.

Meanwhile, in another study, Gerd Leuchs and Luis L. Sánchez-Soto, from the Max Planck Institute for the Physics of Light in Erlangen, Germany, suggest that physical constants, such as the speed of light and the so-called impedance of free space, are indications of the total number of elementary particles in nature.

Vacuum is one of the most intriguing concepts in physics. When observed at the quantum level, vacuum is not empty. It is filled with continuously appearing and disappearing particle pairs such as electron-positron or quark-antiquark pairs. These ephemeral particles are real particles, but their lifetimes are extremely short. In their study, Urban and colleagues established, for the first time, a detailed quantum mechanism that would explain the magnetisation and polarisation of the vacuum, referred to as vacuum permeability and permittivity, and the finite speed of light. This finding is relevant because it suggests the existence of a limited number of ephemeral particles per unit volume in a vacuum.

As a result, there is a theoretical possibility that the speed of light is not fixed, as conventional physics has assumed. But it could fluctuate at a level independent of the energy of each light quantum, or photon, and greater than fluctuations induced by quantum level gravity. The speed of light would be dependent on variations in the vacuum properties of space or time. The fluctuations of the photon propagation time are estimated to be on the order of 50 attoseconds per square meter of crossed vacuum, which might be testable with the help of new ultra-fast lasers.Leuchs and Sanchez-Soto, on the other hand, modelled virtual charged particle pairs as electric dipoles responsible for the polarisation of the vacuum.

They found that a specific property of vacuum called the impedance, which is crucial to determining the speed of light, depends only on the sum of the square of the electric charges of particles but not on their masses. If their idea is correct, the value of the speed of light combined with the value of vacuum impedance gives an indication of the total number of charged elementary particles existing in nature. Experimental results support this hypothesis.


Story Source:

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


Journal References:

  1. Marcel Urban, François Couchot, Xavier Sarazin, Arache Djannati-Atai. The quantum vacuum as the origin of the speed of light. The European Physical Journal D, 2013; 67 (3) DOI: 10.1140/epjd/e2013-30578-7
  2. Gerd Leuchs, Luis L. Sánchez-Soto. A sum rule for charged elementary particles. The European Physical Journal D, 2013; 67 (3) DOI: 10.1140/epjd/e2013-30577-8

Cite This Page:

Springer. "Speed of light may not be fixed, scientists suggest; Ephemeral vacuum particles induce speed-of-light fluctuations." ScienceDaily. ScienceDaily, 25 March 2013. <www.sciencedaily.com/releases/2013/03/130325111154.htm>.
Springer. (2013, March 25). Speed of light may not be fixed, scientists suggest; Ephemeral vacuum particles induce speed-of-light fluctuations. ScienceDaily. Retrieved April 19, 2014 from www.sciencedaily.com/releases/2013/03/130325111154.htm
Springer. "Speed of light may not be fixed, scientists suggest; Ephemeral vacuum particles induce speed-of-light fluctuations." ScienceDaily. www.sciencedaily.com/releases/2013/03/130325111154.htm (accessed April 19, 2014).

Share This



More Matter & Energy News

Saturday, April 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Small Reactors Could Be Future of Nuclear Energy

Small Reactors Could Be Future of Nuclear Energy

AP (Apr. 17, 2014) — After the Fukushima nuclear disaster, the industry fell under intense scrutiny. Now, small underground nuclear power plants are being considered as the possible future of the nuclear energy. (April 17) Video provided by AP
Powered by NewsLook.com
Horseless Carriage Introduced at NY Auto Show

Horseless Carriage Introduced at NY Auto Show

AP (Apr. 17, 2014) — An electric car that proponents hope will replace horse-drawn carriages in New York City has also been revealed at the auto show. (Apr. 17) Video provided by AP
Powered by NewsLook.com
Honda's New ASIMO Robot, More Human-Like Than Ever

Honda's New ASIMO Robot, More Human-Like Than Ever

AFP (Apr. 17, 2014) — It walks and runs, even up and down stairs. It can open a bottle and serve a drink, and politely tries to shake hands with a stranger. Meet the latest ASIMO, Honda's humanoid robot. Duration: 00:54 Video provided by AFP
Powered by NewsLook.com
German Researchers Crack Samsung's Fingerprint Scanner

German Researchers Crack Samsung's Fingerprint Scanner

Newsy (Apr. 16, 2014) — German researchers have used a fake fingerprint made from glue to bypass the fingerprint security system on Samsung's new Galaxy S5 smartphone. Video provided by Newsy
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