Fundamentals of physics confirmed: Experiments testing Einstein's time dilation and quantum electrodynamics

The special theory of relativity of Albert Einstein and quantum electrodynamics, which was formulated by, among others, Richard Feynman, are two important fundaments of modern physics. In cooperation with colleagues from several international universities and institutes, the research group of Professor Wilfried Nörtershäuser (Institute for Nuclear Physics, TU Darmstadt) re-examined these theories in experiments at the GSI Helmholtz Center for Heavy Ion Research.

To explore any possible limits of the two theories, they have been experimentally verified many times already and both have passed all the tests so far. Hence, scientists look for deviations in experiments with increasing precision or under extreme conditions.

For this purpose, Nörtershäuser's team has now accelerated ions to velocities near the and illuminated them with a laser.

The results, which are presented in two new publications, confirm the time dilation predicted for high velocities in the with an accuracy that has never before been achieved. Furthermore, the team provided the first direct proof of a spectral line in highly charged bismuth ions, for which the GSI and other research institutions had been looking for in vain for almost 14 years. 

Einstein confirmed again

In an experiment using the ESR heavy ion storage ring at GSI, the time dilation was measured at a velocity of about 34% of the speed of light. Einstein's prediction that the frequency of a clock depends on its speed is one of the strangest consequences of the theory of relativity. Since macroscopic clocks cannot be brought to sufficiently high velocities, the scientists used atomic clocks in the form of singly charged lithium ions. Einstein himself proposed the basic principle of the experiment. It was carried out for the first time in 1938 by Ives and Stilwell using hydrogen atoms; it was thus possible to prove time dilation with an accuracy of 1%. In modern experiments, these clocks are "read" using two laser beams. One of the beams is traveling in the same direction as the ions and is illuminating the ion from the "back", whereas the other one is counter propagating, illuminating the ion from the "front". Photodetectors are used to observe the florescence of the ions. Fluorescent light can be continuously emitted only when both lasers simultaneously excite the ions with the resonant frequency. When the signal is at a maximum, the frequencies of both lasers are measured. "According to the theory of relativity, the product of these frequencies divided by the product of the known resonance frequencies of the ions at rest must be precisely 1. Any deviation from this would mean that the formula for is incorrect" explains Nörtershäuser.

The result confirms Einstein's prediction to be accurate at a 2 ppb (parts per billion) level, which is about four times more accurate as in the previous experiment, which was carried out at the Heidelberg Test Storage Ring (TSR) at 6.4% of the speed of light.

A 14-year-old mystery has been solved

In a second experiment, the research group achieved a further breakthrough in a precision experiment. Here, (QED) was tested in the strongest magnetic fields available in the laboratory. These fields exist on the surface of heavy atomic nuclei. They are about 100 million times higher than the strongest static magnetic fields that can be produced today using superconducting magnets. These fields become accessible in experiments with heavy, highly charged ions. The experiment used bismuth ions, which have only one electron or three of them left. While the resonance in bismuth ions with only one electron was already measured at GSI in 1994, it was impossible to observe the lithium-like bismuth until recently. But a meaningful test of QED results only from the combination of the two transitions.

These ions were accelerated in the ESR up to about 71% of speed of light and illuminated with laser light. Again, the fluorescence of the was detected to observe the resonance. "When we started with the preparations for the experiment, it quickly became apparent that detecting the fluorescence photons was one of the most critical points" explains Dr. Matthias Lochmann from the University of Mainz. "It is impossible to place detectors around the entire ring. Instead, we positioned a particularly efficient detection system at one point within the ring" says Dr. Raphael Jöhren, a member of Prof. Weinheimer's research team at the University of Münster, describing his contribution to the experiment. Using this detector, a new laser system and sophisticated data acquisition, it was possible for the first time to observe the long-sought transition. Therefore, they were able to eliminate the doubts about the theoretical prediction that had arisen in the meantime.

Explore further

Experiment with speeding ions verifies relativistic time dilation to new level of precision

More information: "Test of Time Dilation Using Stored Li+ Ions as Clocks at Relativistic Speed." Phys. Rev. Lett. 113, 120405, 2014. DOI:

"Observation of the hyperfine transition in lithium-like bismuth 209Bi80+: Towards a test of QED in strong magnetic fields." Phys. Rev. A 90, 030501(R), 2014. DOI:

Journal information: Physical Review Letters

Citation: Fundamentals of physics confirmed: Experiments testing Einstein's time dilation and quantum electrodynamics (2014, October 7) retrieved 24 October 2019 from
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Oct 07, 2014
I would like to point out that since Relativity is also about observers and "reference frames", the experiment is not entirely valid, regardless of who proposed it.

From a certain point of view, yes, the particle itself can be thought of as the "observer" in the co-moving frame, but that is truly a stretch in my opinion.

The Planetary (orbital) Clock paradox, which I proposed, presents a time-dilation related problem which causes contradictory masses of celestial bodies of KNOWN mass to be observed, as a necessary consequence of a change in the length of a second in one frame compared to the other.

Since the article admits there is no way to actually test the "second reference frame" at macroscopic scales, then conclusions based on the theory are more or less of the "circumstantial evidence and it's interpretation" category, rather than an actual "proof".

Oct 07, 2014
Standard interpretation of the theory claims that the mass of the particle, as measured in the other reference frame, must increase with velocity. This appears to come by converting some of the kinetic energy into a more-or-less formless mass-substance via a modified form of "E=mc^2" in reverse.

Well, if this is the case, then the way internal bonds of "objects" in the "co-moving frame" works will be different, because the forces still need to be balanced, even though the masses and the length of a second are supposedly changing. Therefore, the electron gains mass, which obviously means the bonding energy of it's "orbital" must change (somehow, even though it's mostly a quantum value), since we can't be having an electron that is 5% more massive following the same exact orbit under the same exact force...the force equation simply wouldn't work that way.

Therefore you, in the "stationary" frame, cannot simply measure events and consider it as "time dilation"...

Oct 07, 2014
...because you have not taken into account (or at least failed to discuss) the sums of all the other relativistic effects upon the sub-units of the accelerated particle you are observing.

Even the binding energies of the strong, weak, and EM force themselves represent "mass" and that "mass" must be changed as well, assuming mass is relative. If this is the case, then the bonds may be broken under different circumstances, perhaps earlier. The individual particles have more mass, and the "bond" itself has more mass, but the extra "mass" held in the "bonds" has no apparent additional functional force, except possibly gravitational.

This means the bonds need to be stronger not only to hold the constituent particles together, but even to hold themselves together, yet the mass they gain supplies no apparent benefit in this function, as it is simply "degenerate" mass which as no obvious form.

Thus the particles will decay, or will have emission spectra different than time dilation alone.

Oct 07, 2014
So if you are not doing the math for the changing mass of the sub-particles within the atom/ion, then you aren't measuring time dilation accurately. You are measuring a combination of time dilation (assuming it exists,) and relativistic mass (assuming relativistic mass is real) and calling the result "time dilation", when it actually is not.

I have developed a double-perpendicular light clock thought experiment which proves beyond any reason that the relativity equations proposed by Einstein are at best flawed, because there is no doubt that you can produce a logical incongruency via the thought experiment I designed, when using relativity, even though all starting assumptions are in fact valid and identical.

There is no "trick". No smoke and mirrors. One perpendicular light clock on the ground, an identical one goes on an air plane. The clock on the plane will measure two different amounts of duration for the flight, even though the photons are entangled via splitting.

Oct 07, 2014
Now in order to guarantee that relativity is "broken" by the thought experiment, you need to guarantee (initial) synchronicity of the vertical photon and the horizontal photon in each light clock. You do this via a lens or crystal to "split" one photon into two entangled photons. Thus it is impossible for them to not be synchronized. Yet they will each measure a different duration for the flight, and it is unavoidable.

The perpendicular clock on the ground will measure the same duration along both legs, and both of these numbers will be different, according to the theory, than the ones on the plane.

But the plane cannot logically have experienced two different durations for the exact same event as observed in it's own reference frame, but RELATIVITY predicts exactly that: The plane's reference frame will observe a different duration of the flight for each different orientation of a clock inside that reference frame (according to the theory) Which we KNOW does not happen...

Oct 07, 2014
I have developed a double-perpendicular light clock thought experiment which proves beyond any reason that the relativity equations proposed by Einstein are at best flawed
A thought experiment which proves beyond any reason.. indeed! Really, now..

You've inadvertently raised an interesting point. Is the relativistic influence on either clock with respect to the other a continuous one, with no quantum boundaries? Of course it is, and your "thought experiment" has basically already been done in the real world, and relativity has been proved by that experiment. Furthermore, corrections needed to be made to the on-board clocks of GPS satellites because of their high velocities and because they are in free space, where there is negligible gravity. Both of these affect relative temporal frameworks. The precision of their global positioning data was significantly improved by these refinements. Relativity is a fact, like it or not.

Oct 07, 2014
Dyson took Feynman's squiggles and turned it into math. For this he was not awarded a Nobel.

Oct 07, 2014
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Oct 07, 2014
Among other things, note the deliberately indirect me3thod of "verifying" that time dilation occurred. The product of the observed frequencies divided by the product of the rest frequencies must be 1 and any deviation would mean that the formula for time dilation is incorrect. But that would be satisfied if the measure frequencies were 2f and f/2, where f is the rest frequency, 1000000000f and f/1000000000 or even f and f! In other words, the experiment would "confirm" time dilation even if no time dilation occurred!
In fact, "time dilation" "derives" from a special case in "relativity", there is no method for deriving any of the effects from just any circumstance using the "relativity" base tenets.
And "relativity" itself is only an ad hoc development. No one can explain why a system of particles would "decide upon" abiding by a set of rules that, among other things, provides different scales at different forms of motion.

Oct 07, 2014
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Oct 07, 2014
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Oct 07, 2014
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Oct 07, 2014
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Oct 09, 2014
The intense Circular Magnetic Field (CMF) produced by accelerated ions, detected and thought to represents the photon is a wrong interpretation of an important phenomenon. The important question is does QED suggested any mechanism to answer how light (electromagnetic radiation) is generated from electron within an atom (or outside an atom), so that we can think the detected phenomenon is photon?
If not, we need to answer that, or read an answer in "The Electromagnetic Radiation Mechanism," at: http://fundamenta...2_79.pdf

Oct 20, 2014
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Oct 20, 2014
Hi Zeph
Why do you bother when you know your posts are going to be deleted?

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