Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

E really does equal mc2 !

11.01.2006


One of the most striking predictions of Einstein’s theory of special relativity is probably the best known formula in all science: E = mc2. Today, exactly one hundred years after its first formulation, this equivalence has been verified to be correct at least to an accuracy of 4 parts in 10 000 000 ! These measurements, at the Institut Laue-Langevin, Grenoble, and the Massachussets Institute of Technology (MIT), represent the most precise verification of the relation between mass and energy ever achieved.


The GAMS4 instrument. Copyright ILL / Artechnique



The direct test of Einstein’s equation is based on the prediction that when a nucleus captures a neutron, the resulting isotope (mass number A+1) is somewhat lighter than the sum of the masses of the original nucleus (mass number A) and the free neutron (mass number 1). The energy equivalent to this mass difference is emitted as a spectra of gamma-rays.

The mass difference in Einstein’s equation using two silicon isotopes 28-29Si and two sulphur isotopes 32-33S has been measured with very high accuracy on one side of the Atlantic at the MIT, using a novel experimental technique [2].


In parallel, on the other side of the Atlantic at the ILL, the energies of the gamma-rays emitted after neutron capture by both silicon and sulphur, have been measured by an international research team from the National Institute of Technologies and the Institut Laue-Langevin in Grenoble, using the world’s highest resolution gamma-ray interferometer GAMS4 [3]. Thanks to the combination of the very high neutron flux available at the ILL reactor and the exceptional energy resolution of the GAMS4 instrument, it was possible to determine the gamma-ray energies with a precision of better then 5 parts in 10 000 000.

From the comparison between the two values obtained on each side of the Atlantique - the mass difference measurements in America and the energy measurements in Europe -, it was possible to verify Einstein’s equation directly with a precision 55 times more accurate than existing measurements.

Even the most minute deviation from exact equality between energy and mass would have far reaching consequences for the whole of physics as it is today, from an understanding of the building blocks of matter to the evolution of the universe itself. The power of world-leading international collaborations of this kind, using the best facilities throughout the world, are needed to probe ever deeper into the mysteries of science.

Françoise Vauquois | alfa
Further information:
http://www.ill.fr/pages/press/gb/press_releases/E=mc2.htm
http://www.ill.fr

More articles from Physics and Astronomy:

nachricht Solar wind impacts on giant 'space hurricanes' may affect satellite safety
19.09.2017 | Embry-Riddle Aeronautical University

nachricht Integrated lasers on different surfaces
19.09.2017 | The Agency for Science, Technology and Research (A*STAR)

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

Im Focus: Silencing bacteria

HZI researchers pave the way for new agents that render hospital pathogens mute

Pathogenic bacteria are becoming resistant to common antibiotics to an ever increasing degree. One of the most difficult germs is Pseudomonas aeruginosa, a...

Im Focus: Artificial Enzymes for Hydrogen Conversion

Scientists from the MPI for Chemical Energy Conversion report in the first issue of the new journal JOULE.

Cell Press has just released the first issue of Joule, a new journal dedicated to sustainable energy research. In this issue James Birrell, Olaf Rüdiger,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

IVAM’s LaserForum visits the Swiss canton of St. Gallen with the topic ultrashort pulse lasers

06.09.2017 | Event News

 
Latest News

The Wadden Sea and the Elbe Studied with Zeppelin, Drones and Research Ships

19.09.2017 | Earth Sciences

Digging sensors out of an efficiency hole

19.09.2017 | Materials Sciences

Solar wind impacts on giant 'space hurricanes' may affect satellite safety

19.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>