Featured Research

from universities, journals, and other organizations

Einstein In Need Of Update? Calculations Show The Speed Of Light Might Change

Date:
February 12, 2001
Source:
Texas A&M University
Summary:
In 1905, Einstein made major changes to laws of physics when he established his theory of relativity. Now Einstein's laws might also undergo significant changes. Physicists at Texas A&M University and elsewhere have concluded that the speed of light, instead of being the constant value of 186,282 miles per second, might change.

In 1905, Einstein made major changes to laws of physics when he established his theory of relativity. Now Einstein's laws might also undergo significant changes.

Dimitri Nanopoulos, who holds the rank of Distinguished Professor of Physics at Texas A&M University and heads the Houston Advanced Research Center's Group for Astroparticle Physics, established, along with other physicists, that the speed of light, instead of being the constant value of 186,282 miles per second, might change.

In 1905, Einstein established that light was the only object to have a constant speed in all reference frames. This idea was the cornerstone to his theory of relativity, and later to laws of physics.

"If the speed of light proves not to be constant any more, even by a very small changeable amount, laws of physics - the theory of relativity included - will have to undergo significant changes," says Nanopoulos. Nanopoulos, who chairs the Theoretical Physics Division of the Academy of Athens, is among the many physicists who are trying to establish the basis of quantum gravity, a theory that has been dreamed of by physicists since the 1920s.

While they were doing mathematical calculations, Nanopoulos and physicists Nikolaos Mavromatos of King's College in London and John Ellis of the European Center for Particle Physics (CERN) in Geneva, discovered a new expression for the speed of light, which depends on its frequency.

"Through our calculations, we found that the speed of light is frequency-dependent," says Nanopoulos. "But a change in the usual speed of light value of 186,282 miles per second is noticeable only for light coming from astronomical objects situated very far from Earth, which is why this frequency dependence has not been noticed so far."

Physicists are setting up the theory of quantum gravity to put together two major discoveries of physics in the 20th century: the theory of relativity and quantum physics.

The theory of relativity explains both how space and time are related to each other and how gravitation works. Quantum physics describes the workings of the microscopic world, where laws of probability replace the deterministic view used to describe our everyday world.

Until now, physicists have been considering many scenarios for quantum gravity, but these scenarios have never been experimentally confirmed.

The hypotheses put forward by Nanopoulos and his collaborators has been under experimental scrutiny, and the results obtained during the last few months are encouraging.

"One way to experimentally test our hypothesis is to consider galaxies or other objects in the sky that are very far from us," says Nanopoulos. "Then we collect the photons (particles of light) simultaneously emitted by these sources, and we look at differences of arrival times in a detector on earth between photons of different frequencies. The photons of higher frequencies should come later."

The frequency-dependent expression of the speed of light depends on the gravitational constant, a quantity that is known since Newton established his law of gravitation.

By using the differences in photon arrival times of six astronomical sources, Nanopoulos and his collaborators estimated an upper bound of the value of the gravitational constant from the data, and compared their results with the expected value.

"We were amazed to see that if we use all these astronomical data, we find very reasonable values for the gravitational constant," says Nanopoulos. "That was our first surprise: the fact that, put together, a bunch of data that had nothing to do with the gravitational constant, gave us values so close to what we would expect to find."

A second experimental encouraging result about the frequency-dependence of the speed of light was provided by the HEGRA (High Energy Gamma Ray Astronomy) experiment, which is detecting photons from outer space, and is situated in La Palma, Canary Islands.

The frequency-dependent expression of the speed of light was used to solve a problem faced by three physicists: Tadashi Kifune, from the University of Tokyo in Japan, Ray Protheroe, from the University of Adelaide in Australia, and Hinrich Meyer, from the University of Wuppertal in Germany.

The problem occurred when HEGRA physicists detected very energetic photons emitted by the galaxy Markarian 501.

"The most energetic of these photons were expected to interact with other very low-energy photons from the infrared background radiation, which is a radiation present since the early universe," says Nanopoulos. "When a very energetic photon interacts with a low-energy photon, they have just the right quantity of energy to create an electron-antielectron pair. But physicists at HEGRA did not see any of the expected electron-antielectron pairs, but did observe very energetic photons instead.

"By using the frequency-dependent expression of the speed of light, Kifune, Protheroe and Meyer found that the combined energy of each type of photon was not enough to create an electron-antielectron pair," adds Nanopoulos. "That is why no electron-antielectron pair has been observed."

If by looking at more energetic photons, HEGRA never detects the expected electron-antielectron pairs, this would provide further support of the new hypothesis put forward by Nanopoulos and his collaborators.

"This frequency-dependence of the speed of light changes drastically our view of the theory of relativity," Nanopoulos says. "It is also the first time that we have a window of opportunity to study quantum gravity, and thus scientifically study the origin of the Universe. It is a fantastic thing that we can experimentally magnify such a tiny effect."

Nanopoulos says that if the frequency-dependence of the speed of light is further confirmed by other experiments, the theory of relativity would still be valid under certain circumstances.

"There is nothing wrong with Einstein's theory of relativity. If the energy of an object is much smaller than 1019 proton masses or if the distance between two objects is smaller than millions of light-years, Einstein's equations are still valid," he says.


Story Source:

The above story is based on materials provided by Texas A&M University. Note: Materials may be edited for content and length.


Cite This Page:

Texas A&M University. "Einstein In Need Of Update? Calculations Show The Speed Of Light Might Change." ScienceDaily. ScienceDaily, 12 February 2001. <www.sciencedaily.com/releases/2001/02/010212075309.htm>.
Texas A&M University. (2001, February 12). Einstein In Need Of Update? Calculations Show The Speed Of Light Might Change. ScienceDaily. Retrieved August 22, 2014 from www.sciencedaily.com/releases/2001/02/010212075309.htm
Texas A&M University. "Einstein In Need Of Update? Calculations Show The Speed Of Light Might Change." ScienceDaily. www.sciencedaily.com/releases/2001/02/010212075309.htm (accessed August 22, 2014).

Share This




More Matter & Energy News

Friday, August 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Former TSA X-Ray Scanners Easily Tricked To Miss Weapons

Former TSA X-Ray Scanners Easily Tricked To Miss Weapons

Newsy (Aug. 21, 2014) Researchers found the scanners could be duped simply by placing a weapon off to the side of the body or encasing it under a plastic shield. Video provided by Newsy
Powered by NewsLook.com
Flower Power! Dandelions Make Car Tires?

Flower Power! Dandelions Make Car Tires?

Reuters - Business Video Online (Aug. 20, 2014) Forget rolling on rubber, could car drivers soon be traveling on tires made from dandelions? Teams of scientists are racing to breed a type of the yellow flower whose taproot has a milky fluid with tire-grade rubber particles in it. As Joanna Partridge reports, global tire makers are investing millions in research into a new tire source. Video provided by Reuters
Powered by NewsLook.com
Awesome New Camouflage Sheet Was Inspired By Octopus Skin

Awesome New Camouflage Sheet Was Inspired By Octopus Skin

Newsy (Aug. 19, 2014) Scientists have developed a new device that mimics the way octopuses blend in with their surroundings to hide from dangerous predators. Video provided by Newsy
Powered by NewsLook.com
Researcher Testing on-Field Concussion Scanners

Researcher Testing on-Field Concussion Scanners

AP (Aug. 19, 2014) Four Texas high school football programs are trying out an experimental system designed to diagnose concussions on the field. The technology is in response to growing concern over head trauma in America's most watched sport. (Aug. 19) 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