Berkeley: Quest to test Einstein’s speed limit

[bystander]

Quest to test Einstein’s speed limit
University of California, Berkeley | 2013 Jul 29

Albert Einstein’s assertion that there’s an ultimate speed limit – the speed of light – has withstood countless tests over the past 100 years, but that didn’t stop University of California, Berkeley, postdoc Michael Hohensee and graduate student Nathan Leefer from checking whether some particles break this law.

[i]Dysprosium, a rare-earth element used in hard disk coatings, has an unusual electronic structure ideally suited to experiments like this. [b](c) 2013 Theodore Gray periodictable.com[/b][/i]

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The team’s first attempt to test this fundamental tenet of the special theory of relativity demonstrated once again that Einstein was right, but Leefer and Hohensee are improving the experiment to push the theory’s limits even farther – and perhaps turn up a discrepancy that could help physicists fix holes in today’s main theories of the universe.

“As a physicist, I want to know how the world works, and right now our best models of how the world works – the Standard Model of particle physics and Einstein’s theory of general relativity – don’t fit together at high energies,” said Hohensee of the Department of Physics. “By finding points of breakage in the models, we can start to improve these theories.”

Hohensee, Leefer and Dmitry Budker, a UC Berkeley professor of physics, conducted the test using a new technique involving two isotopes of the element dysprosium. By measuring the energy required to change the velocity of electrons as they jumped from one atomic orbital to another while Earth rotated over a 12-hour period, they determined that the maximum speed of an electron – in theory, the speed of light, about 300 million meters per second – is the same in all directions to within 17 nanometers per second. Their measurements were 10 times more precise than previous attempts to measure the maximum speed of electrons.

Using the two isotopes of dysprosium as “clocks,” they also showed that as the Earth moved closer to or farther from the sun over the course of two years, the relative frequency of these “clocks” remained constant, as Einstein predicted in his general theory of relativity. Their limits on anomalies in the physics of electrons that produce deviations from Einstein’s gravitational redshift are 160 times better than previous experimental limits. ...

Limits on violations of Lorentz symmetry and the Einstein equivalence principle
using radio-frequency spectroscopy of atomic dysprosium - M. A. Hohensee et al

• arXiv.org > hep-ph > arXiv:1303.2747 > 12 Mar 2013 (v1), 17 Mar 2013 (v2)

[Ann]

Einstein has not been "proved right" by this experiment. But once again, astronomers and cosmologists have failed to prove him wrong.

Ann

[Chris Peterson]

Einstein has not been "proved right" by this experiment. But once again, astronomers and cosmologists have failed to prove him wrong.

I think you meant this by your use of quotes, but more precisely: the evidence that Einstein was correct has been further extended, and there is still no proof that he was not. Einstein will never be proven right.

[Ann]

Einstein has not been "proved right" by this experiment. But once again, astronomers and cosmologists have failed to prove him wrong.

I think you meant this by your use of quotes, but more precisely: the evidence that Einstein was correct has been further extended, and there is still no proof that he was not. Einstein will never be proven right.

Indeed, that's exactly what I meant, Chris. Einstein can never be proved right. But if he is wrong, he might be proved wrong. Or if his theory is incomplete, as it must be since it isn't compatible with quantum mechanics, it might be possible to see why and where his theory breaks down, in the same way as Einstein could show why and where Newton's theory of classical mechanics breaks down.

Ann

[saturno2]

Recent observations indicated that certain types of neutrinos,broke the limit
of speed of light.
Howewer, this discovery has not been confirmed.

[Chris Peterson]

Recent observations indicated that certain types of neutrinos,broke the limit
of speed of light.
Howewer, this discovery has not been confirmed.

Just the opposite. The observations have been largely disproven, explained by instrumental errors.

[Chris Peterson]

Einstein can never be proved right. But if he is wrong, he might be proved wrong. Or if his theory is incomplete, as it must be since it isn't compatible with quantum mechanics...

That's certainly a possibility, but I wouldn't say it's certain. Although physicists are quite desperate to reconcile GR and QM, I'm not at all certain the Universe requires them to be reconcilable.

[Ann]

Einstein can never be proved right. But if he is wrong, he might be proved wrong. Or if his theory is incomplete, as it must be since it isn't compatible with quantum mechanics...

That's certainly a possibility, but I wouldn't say it's certain. Although physicists are quite desperate to reconcile GR and QM, I'm not at all certain the Universe requires them to be reconcilable.

That's a fascinating thought, Chris.

Ann

[saturno2]

Very important:
" - The Standard Model of particle physics and Einstein´s theory of
general relativity - don´t fit together at high energies"
( Hohensee )
High energies as inter of a black hole, for example

[neufer]

[b][color=#0000FF]The Automated Transfer Vehicle Albert Einstein burning up on Nov. 2, 2013 at 12:04 GMT over an uninhabitated part of the Pacific Ocean. This picture was snapped from the International Space Station. Credit: ESA/NASA[/color][/b]

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Here’s What A Spacecraft Looks Like Burning Up
by Elizabeth Howell, Universe Today, November 5, 2013

<<Flame and fireworks. That’s what the Automated Transfer Vehicle Albert Einstein appeared to astronauts to be like as it made a planned dive into Earth’s atmosphere Nov. 2. The European Space Agency ship spent five months in space, boosting the International Space Station’s altitude several times and bringing a record haul of stuff for the astronauts on board the station to use.

According to the European Space Agency, this is the first view of an ATV re-entry that astronauts have seen since Jules Verne, the first, was burned up in 2008. Controllers moved the spacecraft into view of the Expedition 37 crew to analyze the physics of breakup.>>