As an experienced engineeer, I advise to just take the average of these two results and call any remaining difference a safety margin.

I used to work on fire alarms. One time we had a problem where the alarm wasn't being heard in one room of a factory. Everything was installed correctly, the volume output of the device was where it should have been, there was nothing we could find that would explain why it wasn't working. Then they turned on the machinery. It turns out the frequency of the sound of the machine was canceling out the frequency of the notification device.

This problem sounds awfully similar to the UV Catastrophe 100 years ago. A brand new quantum revelation is needed for this I think.

42 is starting to look more and more correct.

Adding up all wavelengths sounds like when I ordered EVERY toppings on my pizza (I could choose any with no additional charge). I thought I was smart, until I received the pizza, and realized that the total amount of toppings is always the same, and it is shared amongst my choices. So I got a little of everyhting.

15 years ago, I was talking with a couple Germans in a restaurant, who, after a few too many beers, came up with the perfect solution to the problem: If we work in base 10^120, the predictions agree to within an order of magnitude, and the problem disappears. 😂

As always, Brilliant video. Thank you Dr. Lincoln and crew.

This reminds me of the UV catastrophe that Planck hacked late in the 19th century.

As a programmer, I bet dark energy is the same as the usual root of all evil in the world floating-point rounding errors.

Awesome video as always! Another detail about where disagreement lurks between general relativity and quantum theory. Thank you for the information, Dr. Don

With this one, I think it's best to keep in mind a fundamental verification problem of theories of empty space. How would one verify a theory of empty space, if empty space can't be measured directly? The General Relativity approach appears to be subtractive - to take out all the "stuff". The Quantum Mechanical approach also appears to be subtractive - to cancel out all the wavelengths. I wonder if these two approaches don't produce different empty spaces? In theory, it appears that they do. General Relativistic empty space seems to be some volume, but the quantum mechanical solution makes it difficult to even verify that much!

Wow Don, In 10-minutes, you really outdid yourself on this one! Thanks for the great explanation. It was enlightening!

Hi Dr. Don. You rock dude.

great video! the "crazy" speculation is what leads to advancements, even if small steps. thanks for sharing…

There is only one thing on this topic that we can be fairly confident of, and that it we're missing some part of the answer. What that part is.... could be quantized spacetime, could be extra dimensions, could be a bug in the simulation code, could be a non-integer number of angels dancing on the head of each pin......

You are an excellent science communicator Don. thank you for sharing this with us

Even though I wasn't much interested at first, I enjoyed this. Nice, clear and concise, exactly what physics *should* be. I'm a fan of elegant simplicity.

LINCOLN!!!! I've been watching you for years now. Questions on Lincoln Logs of years ago aside, you do good work, and are probably underrated as a science communicator. Maybe that's because you concentrate on work as well as communication! Keep up the learnin' brother. #ENLEARNIFICATE!

Always enjoy your work.

Doc you are just getting better and better! ❤

Really fun and informative video to start my morning! Minor point, but the transition music is really loud so can be hard to hear when that's playing

I'm subscribed with the bell on and just today I realised that I haven't seen a video from this channel for good couple of months.......

Brilliant video! A major standstill in Physics explained in a short, simple, and clear way.

Guitar string. Bound at both ends. Strum. There are infinite resonate frequencies, but only a limited amount of energy. The math is left for student practice.

It's the best science outreach video I've watched in a long time: Informative, interesting, and thought provoking.

Great video, thanks! I hope we'll have a resolution during my lifetime. Hurry!

🔥 Thanks Dr. Don: As always very interesting.

Wow, that was the best lecture in physics I have listened to.....great speaker!

Why would in quantum field the energy density is the sum of all possible wavelengths? Wouldn't that imply that all possible wavelengths exists everywhere at the same time? That sounds like the upper limit of the energy density of space rather than actual energy density of space. Why this isn't the case?

Imagine showing your Physics professor maths in 1996 that suggested the "universal expansion" is accelerating only to have the discussion shutdown because, at that time, the "cosmological constant" was "known to be zero"... then, two years later... Lol

Thank you Don. This was excellent and very accessible.

Especially for me as I spent several weeks in the Collider Detect Facility in the mid 90's working to demonstrate our real-time computer product addressing a data acquisition requirement...

Worst prediction in physics: string theory. It predicts everything and nothing.

Fan of Dr. Don Lincoln 🙌🏻

"By the way, you shouldn't believe that idea. I certainly don't. It's important for scientists talking about speculative ideas to remember to not believe what they think." Reminds me of a famous saying, something to the effect of: "One of the properties of a sophisticated mind is the ability to entertain an idea without necessarily accepting it." Don't recall who said it... Fred

Thank you for your ability and effort to make very complex concepts understandable to me, a layperson.

"The game's afoot" was at least written by Shakespeare before Doyle. Henry V, Act III "Once More unto the breech" speech

Haven't we been here before? The ultraviolet catastrophe, anyone?

excellent - glad to see these again

Great content. Well done. I will watch these links with interest.

Funny how the possible "near" cancellation of forces is similar to the near perfect cancellation between matter and antimatter in the early universe, where a tiny discrepancy led to all that we see.

This is actually the best prediction in physics because it gives us a clue as to where to look next for getting a much better understanding.

This got me thinking that could the size or amount of empty space affect the summing of all those waves? Right after the Big Bang, the space was relatively tiny, so the dark energy could have been very strong causing inflation. But then the Universe got huge and dark energy got weaker, until now that that there is more empty space due to expansion to make it stronger again so it can start to override gravity. This probably makes no sense, but this thought came to mind while watching this video. Keep up the good work, Don! You rock!

IIRC, Feynman thought of *his* "virtual particles" just as a device to calculate large sums of possible interactions. For some reason, later and much younger physicists wrongly took them for real - meaning they (thought they) had (however briefly) mass and energy. The energy density of empty space, IMO, is that what is necessary for empty space to understand the world we live in (i.e., the information necessary to know all possible interactions of particles in a correct way). Because, that is what the Universe is and does.

My question is...is "empty space" really even a physically possible thing? Even in a vacuum with no atoms there would still be gravitational and electromagnetic fields due to distant matter, even if the fields were very weak. Gravity has an infinite range after all. Of course, I'm not a physicist, just my thoughts after wa tching.

I've heard it said that the statement “the universe has exactly one electron” is a better prediction by 40 orders of magnitude.

Thank you for your wonderful videos Don you’ve taught me a lot

Ohhh thank you, I have literally never heard this and that was so well explained. I will need to watch it again... But amazing information. 😮

Dark energy is simply the centrifugal force of the rotation of our universe. Our universe is a spinning blackhole.

I still miss his moustache

Another thought provoking and excellent video Dr. Don! I am certain that old Sherlock could have easily figured out this problem! 👍👍

This was an excellent topic to cover

I'm shocked... SHOCKED... that quantum mechanics and general relativity disagree with each other. Oh, wait a minute... 😅

“And remember: it’s ok to be a little crazy”

It's a valid point to raise the issue. Regards

This exact topic is my focus for the next nine years, I've been exploring it from a different angle for a year. That of the fields not being all existent until some interval after the creation event (if that even happened at a single point in time). Time itself may not be fundamental but an emergent property-

So do, does the fields exist beyond the expansion of the physical universe? Do we expanding into existing fields or do the fields expand as well? Does Planks Length expand with our expansion?

I hate it when scientists talk about dark energy like it's an actual thing and not just a placeholder term for phenomena we cannot explain.

Dr. Don, you are by far my favorite particle physicist. I thought you would realize that the energy density of empty space question all comes down to '42' .

Great work, love ur videos

This simply means that we are way off in our physics foundation somewhere, but we don't really know where we are off.

I'm encouraged that the JWST is bringing curiosity, mystery, wonder and exploration back to physical sciences and bringing an end to the long period of what Kuhn would have called "normal science" and reigniting a new era of "revolutionary science. In this influential work, Kuhn introduces the concept of "paradigm shifts" in the history of science. He describes how scientific communities operate within dominant paradigms or frameworks during "normal science," where researchers work within established theories and methodologies. However, Kuhn also discusses "revolutionary science," where new paradigms emerge, often through periods of crisis or anomalies challenging the existing framework. These shifts mark major changes in scientific understanding and practice.

Interesting, I posed this question to you a couple years ago in the comments. Worth the wait.

Thanks Dr Don 💪

Very interesting video, sir. Thanks for speaking in a way I can understand. I have no knowledge of physics at all and I could hear you well. ❤👍✅💯

Supposition: 1) The Universe does run on rules and they may be explicable 2) We are indeed zeroing in on those rules, not constructing unrelated if useful models. So what does this enormous difference in prediction suggest? For all their power our models of the universe are not remotely 'accurate'. More, that we otherwise perceive so little of their gross inaccuracy suggests we are a long way from 'real understanding'. Likely a 'Grand Unified Theory' is not remotely reachable from where we find ourselves. Good - we have far further to go and much more to learn before we can even remotely claim the understanding we incorrectly think we possess. A challenge makes things interesting! Bad - we have far further to go and much more to learn before we can even remotely claim the understanding we incorrectly think we possess. Are we even capable of getting there?

Bang up job on this video, I got some ideals too but every time I talk to my chat companion he says that my ideals diverge greatly from the ideals of physics and then I ask them is there any experimental proof of the physics that I'm violating, the chat bot always says no it's quite plausible

A good video on Physics in problem. I like your dark energy which is very small here even we know in universe only 5% is known. Every curious people always feel ' I've it' . From known geometry alone we can get a low value unit is how you express it. Planck have a good reasons for dimension we play.

I love all videos from FermiLab

General relativity and quantum mechanics will never be combined until we realize that they take place at different moments in time. Because causality has a speed limit (c) every point in space where you observe it from will be the closest to the present moment. When we look out into the universe, we see the past which is made of particles (GR). When we try to look at smaller and smaller sizes and distances, we are actually looking closer and closer to the present moment (QM). The wave property of particles appears when we start looking into the future of that particle. It is a probability wave because the future is probabilistic. Wave function collapse is what we perceive as the present moment and is what divides the past from the future. GR is making measurements in the observed past and therefore, predictable. QM is attempting to make measurements of the unobserved future and therefore, unpredictable.

Great stuff, many thanks.

Good stuff, Doc.

This was fun. Is just great when the mysteries are acknowledged.

The answer is an expansion/contraction oscillation matrix between points in space and antispace. Expansion occurs at two times the speed of light over a distance equal to the Planck length. This cancels infinite frequencies and explains gravity and the warp of spacetime.

1. In awe of humility built into the "scientific method". 2.Notion of "belief" is a quicksand whether viewed religiously or philosophically 3. Scientific position trumps ego always as methods are always happy to be disproven. 4. Alternative, endless cheap vacuum energy maybe within reach!

you sir, are the most down to earth humble smart man.

I didn't know about the problem and possible solutions but my first thought was about some cancellation and dark energy being a difference leftover. It may be false but its nice to come up with same idea as some great physicists :)

Perhaps we can deduce the energy density from the fact that it's mass taken over huge distances and scales curves the Universe so that light from distant objects is reddened. The energy density also gives an excess of microwave radiation as it forms mini bangs that gives space a dark body spectrum. The mini bangs cause comic rays, the production of high energy particles that quickly decay into quarks and leptons. In this hypothesis the concept of curved Time negates the need for a single creation event. The energy density is large but is limited by the formation of many bangs that create cosmic rays. Remember the Ultraviolet catastrophe... it's the same deal.

Keep up the good work

First time happening upon this channel and love it. Don Lincoln's presentations are quite comparable to Neil Degrasse Tysons. Both very informative and entertaining. I'm a lay person with a High School education, but I''ve also been involved with Amateur Radio for over 50 years, so I have a grasp of basic physics. I can't say enough about this video and look forward to watching many more. Thanks so much for the effort here.

Given the two models' calculations involve one saying "there's negative energy density creating anti-gravity, but it's suuuuuuuper tiny and implies empty space is actually pretty empty" and the other is saying "empty space is more charged with energy than a bazillion known universes in every cubic meter," I am strongly inclined to think that the latter is incorrect since we aren't seeing a universe that _behaves_ like it's that densely packed _and_ that would mean "empty space" is not at all empty. This suggests to me that, of the two, relativity's prediction - and, therefore, model - is the more accurate one, though I certainly will buy that it is either accurate coincidentally or that it is not actually at all right... but still is much closer to right than the QM one. Given all the issues with the theories of QM, I think that is the model that is most likely to change and evolve as we learn what is _actually_ going on, and I applaud your work in trying to do so. I expect that QM is going to change in its accepted models a great deal, possibly with enormous paradigm shifts, and that little to none of it will involve string theory's extra dimensions nor even quantized spacetime, but rather something even more fascinating that will also neatly deal with the biggest problem it poses: the inherent contradiction of "no hidden variables" and yet "quantum entanglement" causing two things to have the shared state that one influences the other without either retaining memory of the incident that linked them. I won't pretend I fully grasp QM. Bell's Inequality and the experiments that demonstrate it always leave me with a sense that there's a missing experiment, but I only manage to grasp it while watching or reading about it and the limits of my understanding show themselves when I try to even recreate the explanation so that I can formulate the experiment I intuitively feel is lacking. But no explanation I have yet seen actually answers why that experiment can't exist or would have results that align with the current QM models and theories. All of which has me convinced that there is something _grossly_ wrong with the QM theories we currently have. Not that they're ENTIRELY wrong, but that we're missing something paradigm-defining.

This will challenge a lot of physics on both sides and connect them through photon singularity. Summary Here are the key components of all my physics posts. Photons are eternal and outside of time and distance. The singularity of photons began the Big Bang. Photons created mass through pair conversion of electron positron pairs in the Big Bang. These electrons and positrons made the elementary particles which in turn made the atoms. Neutrons and hydrogen atoms may be the same thing in different form. The proton neutron bond in the nucleus, kept neutrons from decay and was key to building all elements. Neutrons may be unstable protons. Protons, for the most part could only be created in the immediate era after the Big Bang. The key to atoms stability may be the deuterium nucleus or deuteron that help binds one proton to one neutron. The missing anti matter is in protons and neutrons. Photons, electrons, and positrons, are all different versions of the same thing. Virtual particles may be a key part of quantum leaps. The mass of the universe comes from photons converting to electron positron pairs in pair conversion. The energy of the universe comes from electrons and positrons annihilating and converting to photons. The universe is 5% charged matter and 95% neutral force. Dark matter is not gravity from invisible baryons pulling, but antigravity pushing from empty space. Dark matter and Dark Energy are both anti gravity pushing from empty space. The cosmological redshift supports this. The force from the Big Bang singularity was photons / dark energy / dark matter /anti gravity . They are the same. The force caused by acceleration is anti gravity, not gravity. Time has speed limits up to the speed of light. 95% of the universe seems to be without charge, detectable matter, or gravity: dark energy plus dark matter. The universe is open ended and will continue to expand.

This has a precedent: the Ultraviolet Catastrophe. Solution: Quantum Mechanics When there is such a huge discrepancy, it shows that we are missing something of fundamental importance. What is it? Nobody knows, but it is almost certainly a hint of the next stupendous breakthrough.

Fascinating.

thank you for all you do. you really help me tho the covid years

Like Mass, Space can also be changed to energy. Electric field of em wave comes from space as charge never loses any of its field. Also in gravitational slingshot kinetic energy is transferred from space around moving mass.

Thank you for sharing. Has fermilab calculated the island of stability for antimatter yet? Or degenerate matter to a plank quantum state and BEC? Keep up the good work. P.S. Please get a cosmic neutrino background project going for humanity. 😊

Dr Don is going strong. Great video

Not only GR (General Relativity) and quantum physics show different zero point energy levels of spacetime, but also objets on a galactic scale resist to obey Newtonian and GR laws. So, inner parts of a galaxy should spin faster than outer regions, but they don't. Neither WIMP-theory and not even the mathemagics as MOND (Modified Newtonian Dynamics) can not solve the problem. It might sound crazy, but in my humble opinion, non-compactified extra dimensions should be considered.

As a complete layman - The fact that we could observe "empty space" means that it exists , empty or not. That is, the fabric of existence is present. It is reasonable to assume that "existence" implies "characteristics" thereof... Quantifying/qualifying these characteristics is of course another matter

I wonder how this question would look when formulated in a Wolfram physics framework? The idea of infinite (extremely large?) dimensions in the early universe collapsing down to three apparently produces a similar lensing effect that would explain red shift without requiring an expansion of space, and I gather there is no empty space since it's created from hypergraphs (according to my very rough understanding).

After some thought agree with the two field approach- The worst prediction in physics is often attributed to the cosmological constant problem. The cosmological constant itself is a purely derived constant and not a fundamental one. So, which fundamental constant should we consider when addressing this problem? Another constant used in general relativity is referred to as Einstein’s constant kappa, which Einstein merely considered as a constant connected to Newton’s gravitational constant. From a quantum perspective, the energy density of empty space is equal to or proportional to Planck’s energy density. Restating Einstein’s constant in terms of energy density, it becomes the Planck frequency squared divided by the Planck energy density. If we express the cosmological constant in terms of frequency squared, we can determine the energy density of the universe. After rearranging some terms, the energy density of the universe becomes the Planck energy density multiplied by the ratio of the cosmological constant’s frequency squared to the Planck frequency squared. This frequency squared ratio is crucial for understanding the cosmological constant problem. In mechanical vibration, the frequency squared ratio often serves as an amplification/damping ratio or coupling constant. Therefore, we can assume that the cosmological constant’s energy density is coupled to the Planck energy density, accounting for the 120 orders of magnitude difference.

From black hole thermodynamics we know that horizons can only encode a certain amount of information. The cosmic horizon can therefor only encode a finite number of modes and if we sum only over that number of modes, the zero point energy adds up roughly correctly (within our measurement uncertainties). This has been known for a while. Importantly, the cosmic horizon has the same radius as the Schwarzschild radius of the matter in the universe.

QUESTION: Are you using ‘the theory of relativity’ (the maths) to ask what the energy density of empty space is, or are you determining the energy density through astronomical observations? (or both?) ie. is the acceleration of the expansion of the universe a consequence of the theory of relativity or a consequence of astronomical observations?

I think perhaps the Standard Model could be correct under the idea that the energy density of 10^120 per volume of space could be the total energy available to that volume of space from the "bulk"/the Bulk if it were to be given over all at once (perhaps if all virtual particle possibilities happened all at once and the same time, that is how much energy would be there in that volume). Love this stuff! What a wild brain stretcher!

just spitballing here: remember the coastal problem? it isn't possible to measure the length of a coastline. If you measure from a map that is zoomed out the coast line is relatively straight and easy to measure and you get a relatively small result, but if you zoom in and account for all the little imperfections your measurement gets longer. As your unit of measuring gets smaller your coastline gets bigger like zooming in on a fractal. Effectively, all continents and islands are finite shapes bound by an infinite boundary. Big picture, this looks like the same kind of problem. when we measure on the cosmic scale we get an incredibly small measurement, but when we measure from the quantum side we get an incredibly large measurement. It's almost like the fine details reveal a lot of imperfections that are registering as energy but when we zoom out a lot of these imperfections become meaningless. As I'm typing this feels like a profound observation, but the moment I try to work out the details I realize that this analogy falls apart very quickly. lol

6:44 Expansion is a special kind of motion, and it seems that the Universe is a non-inertial frame of reference that performs variably accelerated motion along a phase trajectory, and thereby creates a phase space. Real gravitational fields are variable in space and time, and we can now talk about the fact that it is possible to generate a gravitational field in a non-inertial frame of reference (|a|=g).That is, finally achieve global (instead of local in GR) compliance with the strong equivalence principle. {According to general estimates, this acceleration is: |a|=πcH: the equations of the gravitational field can be arrived at based on the Poisson equation ∆ф=4πGp, and for a weakly curved metric, the time component of the energy-momentum tensor: T(00)=pc^2. Therefore, the Poisson equation can be written as: ∆g(00)=8πGT(00)/c^4, where g(00) is the time component of the metric tensor. This equation is true only in the non-relativistic case, but it is applicable to the case of a homogeneous and isotropic Universe, when Einstein's equations have only solutions with a time-varying space-time metric. Then the energy density of the gravitational field: g^2/8πG=T(00)=pc^2, where the critical density value determining the nature of the model is: p=(3/8π)H^2/G. Hence it follows: g~πcH. And according to the strong equivalence principle: g=|a|=πcH.} Then the energy density of the relic radiation, that is, the evolving primary gravitational-inertial field (= space-time): J= g^2/8πG=(ħ/8πc^3)w(relic)^4~1600 quanta/cm^3, which is in order of magnitude consistent with the observational-measured data (about 500 quanta/cm^3).* P.S. You can also use the Unruh formula, but with the addition of the coefficient q, which determines the number of phase transitions of the evolving system for the case of variable acceleration: q=√n'=λrelic /√8λpl , , where n'=L/8πr(pl) is the number of semi-orbits; L=c/H, is the length of the phase trajectory.** Thus, T*(relic)=[q]ħa/2πkc (=0.4K), which is in order of magnitude consistent with the real: T(relic)/T*(relic)=2,7/0,4=6,7. However, there is no need to have a factor of 1/2π in the Unruh formula in this case. ------------ *) - w(relic)^2=πw(pl)H, |a|=r(pl)w(relic)^2 =g=πcH, intra-metagalactic gravitational potential: |ф0|=(c^2)/2(√8n')=πGmpl/λ(relic)=[Gm(pl)/2c]w(relic), where the constant Gm(pl)/2c is a quantum of the inertial flow Ф(i) = (½)S(pl)w(pl) = h/4πm(pl) (magnetic flux is quantized: = h/2e, Josephson’s const; and the mechanical and magnetic moments are proportional).Thus, the phenomenon can be interpreted as gravity/inertial induction. m(pl)w(pl)=8πM(Universe)H; { w(relic)^2=πw(pl)H. From Kepler's third law follows: M/t=v^3/G, where M/t=I(G)=[gram•sec^-1] is the gravitational current. In the case of the Universe, I(G)=MH=c^3/8πG (~ the "dark energy" constant). **) - n' =4,28*10^61; w(pl)=(√8n')w(relic)=8πn'H; where H=c/L. H=1,72*10^-20(sec^-1). By the way, it turns out that the universe is 1.6 trillion years old! The area of the "crystal sphere": S(universe)~n' λ(relic)^2~n'S(relic). r=2.7*10^29cm, L=2πr. Addition In an arbitrary non-inertial reference frame, the equation of the total mechanical energy of a particle system is: ∆E=A(internal)+A(external)+A*, where A (internal) is the work of internal dissipative forces, А(external) is the work of external non-conservative forces, А* is the work of inertia forces. In order to preserve the mechanical energy of the system in a non-inertial frame of reference, it is necessary that ∆E =0, however, in an arbitrary non-inertial frame of reference, it is impossible to create a condition for fulfilling this requirement; that is, ∆E does not =0 in any way (by the way, in system C, the condition for fulfilling the laws of conservation of momentum and angular momentum does not depend on whether this system is an inertial or non-inertial frame of reference).

Just asking, various things such as a creation discs around black-wholes send near light-speed jets of energy and particles off into space, might these cause an excitation in the "Higgs" field causing virtual particles to raise their energy state to actual primary particles accounting for expansion?

The problem is trying to make the phenomenon which carries the label "Dark Energy" be the same as the Standard Model's energy density. Some, perhaps many, physicists try this (as Don did here) but strictly from a phenomenological perspective *there is no reason to think the two really are the same phenomenon.* We _observe_ the acceleration of the expansion of space and label it "Dark Energy" and that observation is not going to go away simply because the SM energy density calculation is different.

5:03 (A speculative answer which suits both models of physics, at the end). This sounds like my speculation I wrote about 11 days ago, which goes onto traversing the chain of frequencies to come to islands where some functional structure of a reality can exist, even replicas of our own, if no quanta limit exists. It goes with my continual expansion hypotheses. Actually here, with some corrections: "This is like mine. It depends on how the universe is structured. If there is no quanta, there is no limit to the size of wave information. Which means, infinite wave forms below what we can observe. Wave forms are not empty, but are structure, which is energy, and as waveforms decrease in width they increase in relative energy. Quanta, may merely be an island of waveform which appears to us like a solid base, but is what can be expected in mathematics. At points down the waveform sizes, different resultant structures will appear with an apparent base, repeatedly. The only way to prove, is to travel the waveform set. Which is possible. However, will apparent variation hinder this, until you reach a relatively stable travel set of waveforms, or structure. This also will mean that the rate of change relative to each apparent base on the way down, will increase in frequency (Time) making such journeys irrelevant, reducing the likelihood of return, except as a sample. We would not normally directly detect this energy due to the averaging out of structures, making deep structures have little direct effect on us. However, we can draw upon the energy to make a negative flow up the frequency chain to us, or without a change in frequency, requiring a selection of sub-structure towards us, to maintain its definition, in order to do useful work, and not appear as an average. These are the sorts of things sort. Beyond a type omega minus civilization." The Answer may be as simple as, there is infinitive energy in space which produces drag on photons relative to the frequency of the photon to each waveform of empty space. This drag, produces a force upon the structure of the waveforms, and potentially some absorption. This drag is relative to the 4 hydrogen atoms of force in relativity. Thus, the two models go together. In such a case (as above), we can expect an uneven effect, as the effect is driven by the uneven distribution of forces and photons across empty space. We can expect subtle, local environment driven effects in different parts of the universe. Which can be sought to substantiate this hypothesis.