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Well, certainly this is conjuring up an observation which yet remains to be seen “out there”. However, there IS an observation which may be one of the largest string physics effects ever seen: A cosmic string (!). The corresponding article has been published some time ago and can easily be found in the Cornell archive. Having a really strong clue of a cosmic string (according to a prediction of string theory) sets a very high standard which is hard to be challenged.
If superfluidity sets in at mK-level, the CMB-radiation being around 2.7 K, at least the disk of a spiral galaxy, especially the core (or bubble) is significantly warmer than that (not to mention a galaxy cluster, in which the ICM heats up pretty much), it is hard to understand how the mK-level could be attained and maintained. Unless this is explained to the inclined visitor, it is an interesting theory, but lacks physical relevance.
By the way: Wasn’t it mentioned earlier that dark matter is NOT a particle known from the Standard Model ?! Now we are told about dark matter atoms ?! MOND is indeed worth while pursuing. For one, the presented evidence of galaxy rotation curves fit extremely well, even as prediction (!). Then, the Cornell archive contains lots of articles dealing with MOND and confirming the applicability for galaxy clusters as well (there are some fundamental misinterpretations around which obviously are maintained here). Moreover, and this is a hypothesis intensely discussed lately: the MOND-acceleration is pretty much in the same order of magnitude as the multiplication of H (the Hubble factor) and c (speed of light); an extremely fundamental relationship that should be examined further.
I consider it unlikely that dark matter could be a particle, given the contents of the Standard Model and the decades of intensive research (theory und experiments) since the assumption of unseen matter, added by the discovery via the HST that there are about ten times more galaxies in our universe than previously estimated. So, there IS matter that had not been seen so far. (First line of argument.)
Then, it has been an assumption that Kepler’s laws would apply to large objects (a reasonable one, but an assumption nonetheless). There are different theories around that don’t share that assumption, and one of the most convincing one is MOND (by Milgrom). Very strong evidence, added by explanations for observations that cannot be done otherwise. (Second line of qrgument.)
As a “jury member”, my vote would be against dark matter. It has also been observed (HST) that there are about ten times as many galaxies in our universe than estimated earlier. Unfortunately, there has (to my current knowledge) not been any follow-up analysis as to whether this discovery could “balance” the suggested amount of dark matter”. But given the failure of any evidence of a dark matter particle despite enormous efforts over a large timeframe, given this discovery of much more matter in our universe than estimated, my conclusion would be to dismiss dark matter and turn to the real matter that had not been seen earlier.
Obviously Dark Energy is as real as inflation is, and it is most likely the same thing, just at a significantly different level of its potential energy, which these days is some 10^120 or so less than at the “ignition” of the universe. We assume (and hope) that we have arrived at the minimum level of this inflaton potential – and not a “false” one; if so, the ultimate fate could be a transfer (tunneling) from this false to the true minimum, with devastating results.
It was the Israel physicist Milgrom who suggested the MOdified Newtonian Dynamics, MOND, which from the beginning solved the puzzle of the galactic rotation, confirming several predictions since then. Zwicky’s idea was the stroke of a genius at the time, and Rubin did no less. Of course it was necessary to try to find this unseen matter. A survey with the HST revealed about 10 times more unseen galaxies than accounted for so far. The gap is closing. Consequently, I think that both ways need to be taken: Observe, evaluate – and don’t rule out anything prematurely.
The 4% only came in when the accelerated expansion of our universe was discovered, soon coined “Dark Energy” (aka cosmological constant and still confused with the vacuum energy or vacuum expectation value, which is a different story). It was this discovery that affected my assessment of how much we do NOT know – yet.
You said earlier that a true paradox invalidates a theory. Here you claim that the paradox is NOT solved, which implies that the Theory of Special Relativity is false. Btw: An entirely different situation compared to the Twin Paradox, which turned out to be false, as one of the twins left the common frame of reference and accelerated away (and back); hence confirming the theory of SR. (To note, for good measure: This paradox is solvable in the same way as the twin paradox’s is.)
Time is not seen as a dimenson by everybody (not even by Einstein himself, if memory serves). This makes the “diversion”-idea quite troublesome (or awkward). Even the “diversion” thought itself doesn’t make things any transparent: Given space dimensions, a time “dimension” is necessarily something entirely different and cannot be compared 1 to 1.
There are several significant flaws in this story, which would impact, to name a very similar example, the “twin paradox”. Transferring this example to the twins, the leaving twin would have to post-process his brother’s clock, setting it back conveniently to reach some analogue result as in this example. The key point is that the start, both with the twins as in this example, represents a COMMON frame of reference, which one is leaving. There is no point in suggesting that the partner is moving whilst it should be very clear who the moving part is – both in the twin paradox as here (again) between George and Gracie. The example means stretching relativity beyond the limits.
I’m not convinced at all:
There is a past which we can trace back, on a cosmic scale right down to the big bang, and we are fairly sure about the cosmic history or, if you will, the cosmic past – on large scales.
The present is a “floating” point transferring permanently from the past to the future. For us humans, it should be one of the major endeavors to “grab the moment” and live it.
The future is unknown. We can speculate to some extent and on some scales what the future might hold, such as the transformation of our Sun into a red giant and then a white dwarf, or the mergers first with Triangulum and later with Andromeda or, looking out even farther both into space and time, the picture of “our” cosmos being a single, quite massive galaxy – and nothing else within what we know as the cosmic horizon.
Something like a “now slice” ? I consider it absolutely meaningless, and it certainly is different from any idea of simultaneity (which we usually understand to have some meaning in terms of mutual relation, being between events ot in relation to us).