Since the late 1920s, astronomers have been aware of the fact that the Universe is in a state of expansion. Initially predicted by Einstein’s Theory of General Relativity, this realization has gone on to inform the most widely-accepted cosmological model – the Big Bang Theory. However, things became somewhat confusing during the 1990s, when improved observations showed that the Universe’s rate of expansion has been accelerating for billions of years.
This led to the theory of Dark Energy, a mysterious invisible force that is driving the expansion of the cosmos. Much like Dark Matter which explained the “missing mass”, it then became necessary to find this elusive energy, or at least provide a coherent theoretical framework for it. A new study from the University of British Columbia (UBC) seeks to do just that by postulating the Universe is expanding due to fluctuations in space and time.
The study – which was recently published in the journal Physical Review D – was led by Qingdi Wang, a PhD student with the Department of Physics and Astronomy at UBC. Under the supervisions of UBC Professor William Unruh (the man who proposed the Unruh Effect) and with assistance from Zhen Zhu (another PhD student at UBC), they provide a new take on Dark Energy.
The team began by addressing the inconsistencies arising out of the two main theories that together explain all natural phenomena in the Universe. These theories are none other than General Relativity and quantum mechanics, which effectively explain how the Universe behaves on the largest of scales (i.e. stars, galaxies, clusters) and the smallest (subatomic particles).
Unfortunately, these two theories are not consistent when it comes to a little matter known as gravity, which scientists are still unable to explain in terms of quantum mechanics. The existence of Dark Energy and the expansion of the Universe are another point of disagreement. For starters, candidates theories like vacuum energy – which is one of the most popular explanations for Dark Energy – present serious incongruities.
According to quantum mechanics, vacuum energy would have an incredibly large energy density to it. But if this is true, then General Relativity predicts that this energy would have an incredibly strong gravitational effect, one which would be powerful enough to cause the Universe to explode in size. As Prof. Unruh shared with Universe Today via email:
“The problem is that any naive calculation of the vacuum energy gives huge values. If one assumes that there is some sort of cutoff so one cannot get energy densities much greater than the Planck energy density (or about 1095 Joules/meter³) then one finds that one gets a Hubble constant – the time scale on which the Universe roughly doubles in size – of the order of 10-44 sec. So, the usual approach is to say that somehow something reduces that down so that one gets the actual expansion rate of about 10 billion years instead. But that ‘somehow’ is pretty mysterious and no one has come up with an even half convincing mechanism.”
Whereas other scientists have sought to modify the theories of General Relativity and quantum mechanics in order to resolve these inconsistencies, Wang and his colleagues sought a different approach. As Wang explained to Universe Today via email:
“Previous studies are either trying to modify quantum mechanics in some way to make vacuum energy small or trying to modify General Relativity in some way to make gravity numb for vacuum energy. However, quantum mechanics and General Relativity are the two most successful theories that explain how our Universe works… Instead of trying to modify quantum mechanics or General Relativity, we believe that we should first understand them better. We takes the large vacuum energy density predicted by quantum mechanics seriously and just let them gravitate according to General Relativity without modifying either of them.”
For the sake of their study, Wang and his colleagues performed new sets of calculations on vacuum energy that took its predicted high energy density into account. They then considered the possibility that on the tiniest of scales – billions of times smaller than electrons – the fabric of spacetime is subject to wild fluctuations, oscillating at every point between expansion and contraction.
As it swings back and forth, the result of these oscillations is a net effect where the Universe expands slowly, but at an accelerating rate. After performing their calculations, they noted that such an explanation was consistent with both the existence of quantum vacuum energy density and General Relativity. On top of that, it is also consistent with what scientists have been observing in our Universe for almost a century. As Unruh described it:
“Our calculations showed that one could consistently regard [that] the Universe on the tiniest scales is actually expanding and contracting at an absurdly fast rate; but that on a large scale, because of an averaging over those tiny scales, physics would not notice that ‘quantum foam’. It has a tiny residual effect in giving an effective cosmological constant (dark energy type effect). In some ways it is like waves on the ocean which travel as if the ocean were perfectly smooth but really we know that there is this incredible dance of the atoms that make up the water, and waves average over those fluctuations, and act as if the surface was smooth.”
In contrast to conflicting theories of a Universe where the various forces that govern it cannot be resolved and must cancel each other out, Wang and his colleagues presents a picture where the Universe is constantly in motion. In this scenario, the effects of vacuum energy are actually self-cancelling, and also give rise to the expansion and acceleration we have been observing all this time.
While it may be too soon to tell, this image of a Universe that is highly-dynamic (even on the tiniest scales) could revolutionize our understanding of spacetime. At the very least, these theoretical findings are sure to stimulate debate within the scientific community, as well as experiments designed to offer direct evidence. And that, as we know, is the only way we can advance our understanding of this thing known as the Universe.
Further Reading: UBC News, Physical Review D
Why would this sub-microscopic fluctuation average to expansion and not contraction or if it is truly random more likely average to neutral?
Another mathematical attempt to salvage theories which evade any experimental or observational proof. The continued use of mathematics to attempt to support these preposterous and wholly illogical theories should be a huge red flag. Either way, these theories have demonstrated no predictive value which should be another red flag. The fact that these theories are based on concepts which fall outside the scope of the known laws of physics should be the final straw. It is clearly past time to thoroughly inspect alternate theories (i.e. the electromagnetic models put forth by Thornhill and Scott) which are consistent with the known laws of electrical engineering and plasma physics, have shown excellent predictive value and have both experimental and observational support. Whether or not you have the courage to do this here, the validity of this model is being seriously addressed in many other forums.
The EU electric Sun hypothesis is only being seriously addressed in a very few other discredited forums.
Yes, it is being interjected into forums like this one, but that does not make it valid.
What ever made you believe in this constantly needing to be revised, hypothesis?
Ken
The EU theories seem to be increasingly verified as the newest radio telescope data arrives.
I find the interpretations of this data by Scott and Thornhill to be convincing. Their models for the data are consistent with the known laws of plasma physics and electrical engineering. Their models have also been shown to have predictive value.
These just seem more logical and also have experimental evidence to support them.
For these reasons I believe they deserve serious consideration. The utter lack of predictive value and the dependence upon unproven concepts ( i.e. dark matter, dark energy, singularities) makes the current standard model very unattractive as well as unlikely to be correct.
Brian Tray, M.D.
“I am QUITE pompous and happen to be one of the VERY lucky few that really understands what’s going on! Listen to how superior I and my handful of other crackpot compatriots are! BWAHA-HA-HA-HA-HAHAHA! I know more than sci-ence… I know more than sci-ence!”
It’s no excuse to act like a 10 year-old.
The universe is excellent at keeping its deepest secrets.
This concept is appealing. Why should a universe as mysterious as this have to behave in a uniform way at all times?
It’s just a desperate effort to save the wrong theory – general relativity because Einstein’s relativity theory has already been disproved both logically and experimentally (see “Challenge to the special theory of relativity”, March 1, 2016). A press release for the paper has been published on Eurekalert website for the same length of time (https://www.eurekalert.org/pub_releases/2016-03/ngpi-tst030116.php), plus numerous comments on Nature, Science and many other websites. I just don’t understand why science reporters and physicists just keep ignoring all these and continue writing articles and papers on the wrong theory. Science is not a religion which is based on belief. Science should pass strict logical reasoning. Einstein’s relativity theory just fails in the logical reasoning.
The most obvious and indisputable experimental evidence, which everybody with basic knowledge of special relativity should immediately understand: is the existence of the absolute time shown by the universally synchronized clocks on the GPS satellites which move at high velocities relative to each other while special relativity claims that time is relative (i.e. the time on each reference frame is different) and can never be synchronized on clocks moving with relative velocities.
Many physicists claim that clocks on the GPS satellites are corrected according to both special relativity and general relativity. This is not true. The corrections of the atomic clocks on the GPS satellites are nothing to do with relativistic effects because the corrections are absolute changes of the clocks, none of which is relative as claimed by special relativity. After all corrections, the clocks are synchronized not only relative to the ground clocks but also relative to each other.
Some people may argue that the clocks are only synchronized in the earth centered inertial reference frame, and are not synchronized in the reference frames of the GPS satellites. If it were true, then the time difference between a clock on a GPS satellite and a clock on the ground observed in the satellite reference frame would grow while the same clocks observed on the earth centered reference frame were keeping synchronized. If you corrected the clock on the satellite when the difference became significant, the correction would break the synchronization of the clocks observed in the earth centered frame. That is, there is no way to make a correction without breaking the synchronization of the clocks observed in the earth centered frame. Therefore, it is wrong to think that the clocks are not synchronized in the satellite frame.
Actually, on the paper mentioned above, I have proved that if clocks are synchronized in one inertial reference frame, then they are synchronized in all inertial reference frames because clock time is absolute and universal.
Similarly, all the differences of the clocks in Hefele-Keating experiment were also absolute (i.e., they were the same no matter whether you observe them on the moon or on the space station). Therefore, they are nothing to do with relative velocity caused time dilation as claimed by special relativity. It is simply a wrong interpretation that the differences of the displayed times of the clocks are the results of relativity.
The increase of the life of a muon in a circular accelerator or going through the atmosphere is also an absolute change which is the same observed in all reference frames.
Therefore, all these so-called relativistic effects are not relative at all, nothing to do with relativity.
The simplest thought experiment to disprove special relativity is the symmetric twin paradox: two twins made separate space travels in the same velocity and acceleration relative to the earth all the time during their entire trips but in opposite directions. According to special relativity, each twin should find the other twin’s clock ticking more slowly than his own clock during the entire trip because of the relative velocity between them as we know that acceleration did not have any effect on kinematic time dilation in special relativity. But when they came back to the earth, they found their clocks had exact the same time because of symmetry. This is a contradiction that has disproved special relativity. This thought experiment demonstrates that relativistic time is not our physical time and can never be materialized on physical clocks.
That is, time is absolute and space is 3D Euclidean. There is nothing called spacetime continuum in nature. The visible universe is filled up with a fluid – aether which is responsible for the propagation of light.
It seems that the mass of aether provides the extra gravitation in the space and its pressure is responsible for the accelerating expansion of the universe.
No, General Relativity has been proven time and time again. You are entitled to your own opinions, but not your own science. In fact, commenting in a scientific publication is a waste of time if your only interest is in peddling fringe theories and don’t even know what you are talking about.
Huzzah!
General relativity is still a theory that is still unproven. The evidence used to support it was gravitational lensing. This interpretation of data was faulty as the results can explained by simple diffraction. Also, since light has no mass gravity should have no effect upon it.
Even Einstein had grave misgivings about relativity due to the findings he referred to as “spooky action at a distance”. These quantum physics findings directly oppose relativity. It is becoming ever so clear that C is not Vmax which would invalidate the theory of relativity. This is the reason that Tesla referred to relativity as a “beggar in a purple robe”.
So rest assured,for these reasons and many more, relativity is still just a popular theory.
It is not unproven, repeated experiments since 1915 have have born it out. These started with the perihelion precession of Mercury, moved on to redshift experiments, and have since included modern cosmological simulations that examine the evolution of the Universe over the course of billions of years. There were all consistent with Einstein’s field equations, as was the discovery that the Universe is in a state of expansion.
Also, it is well known that gravity has an effect on light because it bends space-time, which alters the course light takes – consider black holes. Mass doesn’t even come into it! And Einstein’s comments were not an expression of doubt with relativity, it had to do with his dismay over the possibilities arising out of Bohr’s theories and quantum mechanics.
Like I said, you are not entitled to your own facts or science, so please don’t misrepresent things based on ignorance or reject established theories you clearly don’t understand.
No, your comment is wrong. A correct theory should withstand all challenges. If it fails only in one case, it should be thrown away no matter how many so-called proofs you can list. Einstein’s relativity has been disproved as I presented. If you want to defend relativity, you should refute my points, rather than meaningless blames.
If there was anything worth refuting, I would do so. But as it stands, there is not. You’ve offered nothing more than opinion and a single paper, which you claim is enough to refute Relativity. This is not only arrogant in the extreme, it betrays a deep ignorance of the century of proofs for relativity, and how the scientific method works. You don’t prove or disprove something once, you have to do it over and over, which Einstein’s field equations have been.
As for “blames”, I’ve made none. I simply reject fringe reasoning on behalf of people who assume they know more than the actual scientific community, but in reality, don’t even know what they are talking about.
Matt, are you totally blind? Not to mention the details in my paper, my comment itself has listed to evidences that are enough to disprove relativity.
No you have not, you’ve listed proofs that do not hold up to scrutiny and which can be easily disproved (and have been by others comments) by citing reputable research. Your ignorance in this matter is apparent and your attempts to discredit relativity have no value in any scientific discussion.
Here’s one your spellchecker missed in para 2:
” . . . it then became necessary to find this illusive energy . . . “