Also
https://news.ycombinator.com/item?id=43372271 ("Is our universe trapped inside a black hole? This JWS Telescope discovery (space.com)", 56 comments)
https://news.ycombinator.com/item?id=43372271 ("Is our universe trapped inside a black hole? This JWS Telescope discovery (space.com)", 56 comments)
This is the subtitle of the article. It’s such a great summary!
Does it mean that we are, potentially, on one of two poles(?) of the observable universe, if we're observing most galaxies around us rotating a certain way?
Or maybe they're just billboard sprites, always facing the camera, with clockwise animations.
> "The re-calibration of distance measurements can also explain several other unsolved questions in cosmology such as the differences in the expansion rates of the universe and the large galaxies that according to the existing distance measurements are expected to be older than the universe itself.”
Or is it just relative to all the other galaxies?
Related question: the horizon of a black hole is expanding when the mass increases. Could this map to the expansion of our universe, which seems to expand faster and faster?
But if objective spin directions are roughly evenly split because the universe is isotropic, the spins from our viewpoint ought to be evenly split as well.
If they're not evenly split, the universe must have a preferred axis, which would be an amazing discovery. I guess if the preferred axis just happens to align with our own galaxy, that would support the alternative theory that it's due to an observation effect such as doppler shift.
Either way, it's incredibly cool to have such a simple but totally unexpected observation pop up out of nowhere.
How does this work? The page it links to doesn't explain why rotation would matter.
Edit: To clarify - one side of the galaxy would be moving towards us, and one away from us, no matter which direction it spins in, so this should not affect the average brightness of the entire galaxy.
The original paper (https://academic.oup.com/mnras/article/538/1/76/8019798?logi...) links to a few papers discussing this, among them https://www.mdpi.com/2073-8994/15/6/1190 It doesn't answer my question (or if it does, I didn't understand it), but it gives a magnitude for the expected effect on brightness - 0.6%. I do not think that would explain the 1:2 ratio of observed spin directions.
If I'm following correctly, the "we're inside a black hole" idea is a major reach, connecting at least two unrelated concepts (black holes could contain baby universes; black holes have spin). But it's a really interesting idea and not obviously wrong.
"A preferred axis in our universe, inherited by the axis of rotation of its parent black hole, might have influenced the rotation dynamics of galaxies, creating the observed clockwise-counterclockwise asymmetry,” Nikodem Poplawski
I found this a little surprising as well
I imagine there was already a preferred spin of gases immediately after the big bang, just due to random chance, so why wouldn’t that be preserved more or less?
But how does that work?
Matter-antimatter ratio
Left vs right handed molecules
Now galaxy spin directions
Maybe there are others I missed too
I can’t figure out why the Doppler Shift would make the entire galaxy brighter. I assumed it would make the rotation side spinning towards us brighter. But also redshift the side spinning away.
"the rapid decay of pions is governed by the weak force — the only fundamental force with a known mirror asymmetry"
https://www.quantamagazine.org/cosmic-rays-may-explain-lifes...
That would seem way more surprising than relative to a arbitrarily selected common upwards direction and it would imply that we are somehow at the center/top of the universe.
Note that this is not that easy to determine:
When done manually, the determination of the direction of rotation of a galaxy can be a subjective task, as different annotators might have different opinions regarding the direction towards a galaxy rotates. A simple example is the crowdsourcing annotation through Galaxy Zoo 1 (Land et al. 2008), where in the vast majority of the galaxies different annotators provided conflicting annotations. Therefore, the annotations shown in Fig. 1 were made by a computer analysis that followed a defined symmetric model (Shamir 2024e).
I'm not sure about the other examples. But maybe it's a similar reason that it is not a 50:50 ratio?
2. If we are inside a black hole, where is the singularity?
Study is at around 3σ (like 62 heads in 100 flips). It is more likely that future studies disprove it, and this is an issue with the methods, if I am of the betting type... :-)
It would also imply that our whole universe is rotating - the only reason this happens on Earth is because of our planets rotation and the Coriolis effect.
Hence the farther we observe stuff, the earlier in time it happens. And if an observer moves to a different location, they will still be at the center of the universe (aka light cone).
High energy can spontaneously form matter antimatter pairs. In the early universe, the heat of the universe was very high, so this was common, constantly happening.
The problem as always if fine tuning. If the early universe was 60-40, that would be understandable. If the early universe was precisely 50-50, that’s fine too. But the universe was 50.0001-49.9999 or something like that, and then all annihilated. It’s too big a difference to easily be random chance, and too small a difference to be easily explained by a starting condition what wasn’t precisely tuned by some mechanism.
I think it's enough to say that it was spinning. There was an imbalance tending toward a direction.
I think there is a men in black scene, where an alien is rotating the universe globe like a toy they are playing.
(Though one of the papers notes that the tiny change in brightness this causes isn't enough to explain the large difference in spin directions)
And just like there is no still point in the universe, there is no up or down. So yes, it may be true that, IF you select a couple of arbitrary points in the universe to be up and down, THEN you can count how any galaxies spin left vs right. And it is way cool to find out that it doesn’t appear to be 50/50, and to wonder about why. But I think the article author did the readers a disservice by glossing over the “no up or down” fact.
Or maybe not, anyways back to work.
While we don't believe we're the center of the universe, I believe we're limited by instrumentation to determine its size. Best guess now is 100B LY in diameter.
The one thing that stuck with me is how frequently things we believe to be true are disproven.
This does not surprise me:
> “If that is indeed the case, we will need to re-calibrate our distance measurements for the deep universe,”
But the observable universe is a fraction of the whole thing. The "best guess" right now is that the total universe is flat and has no end.
If it's bounded, 100B LY is orders of magnitude below the most conservative lower-bound estimates, which I believe start at around 300-500x that size. (With huge error bars on all sides.)
What the original article explains, is that this is relative to our observer point of view (obviously).
It's still very interesting, since, disregarding any potential interaction in our local group, randomness was expected and we should see around 50/50 rotating either way unless one of the explanations came into play.
I can’t think of any that would make much sense as top/bottom would mean that there needs to be a relative universal point to reference and as far as I know, that doesn’t exist.
Did it require JWST to notice this, or did we just _not check_ until now?
Is there a notable asymmetry in, say, the spin directions of galaxies contained in the Hubble XDF?
EDIT:
This doesn't make a lot of sense. Lior Shamir has written that a lot of unrelated sky surveys recently have shown an asymmetry in the past few years, but only down around ~2%.
https://www.mdpi.com/2073-8994/16/10/1389
https://aas.org/sites/default/files/2020-05/lior_aas236.pdf
JWST's asymmetry in both early work and more recent deep fields is more than an order of magnitude stronger.
EDIT2: Notably they show anisotropic asymmetry: The galaxies are different rotations when you look in different directions, with something like +6% in one direction and -5% in another. But still nothing like the +50% now being reported as a general feature.
Organic chemistry found on meteors shows that non-terrestrial sources are equally left vs right-handed.
However, the rest might be caused by one or more errors in our premise. The most likely culprit being cosmological principle.
or i suppose this is clockwise/counterclockwise in regards to the direction they're moving in?
2/3 doesn't seem that significant if they think it should be a 50/50 split, we might just not be seeing enough
That doesn't make sense for this particular context though. The direction of "up" of another galaxy doesn't change depending on where you are as an observer...
Then again, it's only two-thirds of the galaxies that have "up" facing us - which isn't that surprising. If something like 99% of their "up" was facing us it would seem more special.
I think in general it would be unusual if they didn’t rotate. Any large non-uniform mass of gas or rocks when colliding will induce some rotation. What is odd though is that for galaxies we see more of them spinning one way than another.
Would that be same kind of question as “where did the Big Bang come from?”. That’s a lot of energy that came from somewhere as well seemingly for no good reason.
I also wondered immediately about dark matter; could it be that’s where the counter-balance of momentum went? Like most galaxies spin one way and most dark matter would then have to spin the opposite way.
I am not a physicist so this is all random guessing of course.
Whatever asymmetry you're visualizing for one galaxy, its mirror-image galaxy is equally physical, and possesses the same asymmetry.
Which would also be the reason we have the laws of physics we do in general.
Anything seemingly ad hoc in our universal (from our vantage) viewpoint is potentially explainable as a pocket among all other possible distributions/combinations of relations.
The other question is - what does the rotation of our own galaxy have to do with it? Let's keep the Solar system as is, and mirror the rest of the Milky Way around it, so that it is now spinning the opposite direction. Why should this affect the apparent brightness of other galaxies? Especially since the Solar system is effectively moving in a straight line, on the scale of a human lifetime.
But between any point in one galaxy to another, just as much matter will be moving closer as moving away. Regardless of same or opposite rotations.
But perhaps greater red shift and greater blue shift (as apposed to lesser of both) as a practical matter of telescopes vs. their cross spectrum sensitivities, means more light detected.
I see no way it influences the light emitted, but maybe I heard just too little of physics? BTW, does the direction of magnetic field of galaxies correlate with the direction of their rotation?
edit: Ah, maybe magnetic field can polarize the light? And when you have two magentic fields they polarize in one direction or in two different, and maybe it influences observed brightness of the light? Or maybe it is just an uninformed guess?
That seems like an example of "streetlight effect." The streetlight effect, or the drunkard's search principle, is a type of observational bias that occurs when people only search for something where it is easiest to look.
Pardon the cheesy domain name, the content is very relevant.
Maybe there is an 'incentive' for universes to form with physical constants tuned to produce black holes with the available energy in that universe.
https://www.comsol.com/blogs/why-do-tennis-rackets-tumble-th...
Spiral galaxies spin, they do not tumble unless hit by another galaxy.
Elliptical galaxies are like gravitational convection and don't really have cohesive "rotation", however.
You can say the exact same thing about mass. Obviously it came from somewhere. And it could have taken angular momentum with it.
This means that all known ways to create or destroy matter, also creates or destroys an equal amount of antimatter.
It turns out that most attempts to extend the Standard Model allow violations of baryon conservation. This could explain the dominance of matter in our universe. However none of those attempts have been able to make any predictions that matched experiment. And so it remains true that all known physical processes perfectly conserve the baryon number.
(It is also possible that baryon number really is conserved, and dark matter is actually dark antimatter. But we lack a theory of what dark matter could be that predicts this.)
This property of this set of 8 particles is analogous to the similar property of the set of 2 particles composed of a particle and its anti-particle, and to the similar property of the sets of 4 particles that can be involved in a weak interaction (the intermediate weak bosons convert one 4-particle interaction into a couple of 3-particle interactions, but when looking at the overall inputs and outputs, all the weak interactions are 4-particle interactions), which ensure the conservation of various quantities over such interactions.
This means that it is possible to conceive an additional kind of interaction, which unlike electromagnetic interactions between 2 particles and weak interactions between 4 particles, involves 8 particles, so it has a much smaller probability of occurring, i.e. it is a much weaker interaction than the weak interaction, and through which, when provided with enough energy, quarks + electrons + neutrinos could be generated simultaneously without generating anti-matter.
While there is no evidence yet for such an interaction, it is conceivable that at least during the circumstances of the Big Bang, such an interaction could have existed, so all the quarks and leptons could have been generated from some unknown bosons, just with enough initial energy and with conservation of all quantities for which there are solid reasons to believe that they must always be conserved, like energy, linear momentum, angular momentum, electric charge and color charges. (Unlike for the baryon number, for which there is no other reason to believe that it must be conserved, except that the strong, weak and electromagnetic interactions happen to have this behavior.)
Maybe black holes don't have a singularity:
There's nothing special about matter or antimatter. Same energy, just opposite charge. All else being equal, they should be created in equal amounts. As far as we're aware, there is no special property that would make the universe preferentially create more matter than antimatter.
There's also no requirement that the configuration of matter and antimatter be "stable" for whatever definition you want to apply. The only rule is that conserved quantities stay conserved.
[^]: Ignoring ejections. But black holes also don’t “eject” mass. Or maybe they do? Hawking Radiation is weird.
The important part is that at any given point on the elastic strip, both sides are getting further away. Everything else is getting further away.
You might think if A-B-C-D are points on the tape and A-B are expanding and C-D are expanding, then B and C must be squished together, but the distance between them is also expanding. You have infinite elastic, but you also have infinite room to stretch it (even along the direction it already occupies). You now have A--B--C--D.
It's tempting to think about that stretch from the point of view of the floor/table beneath the elastic, in which case some parts of the elastic move faster than others as they stretch, but if you always think from a point on the elastic, then the speed of the rest of the elastic depends on how far away it is. Stuff twice as far away moves away twice as fast. Stuff infinitely far away moves away infinitely fast. That's true for every point on the elastic. No bunching up.
I never finished the book, but this reminds me of God's Debris by Scott Adams which explores a philosophy of pandeism (where God annihilated itself and became the universe).
In other words, your observable universe is different than mine and that's both spheres we're in the middle of. That suggests the universe itself probably isn't a sphere.
If you flip 2n fair coins, you expect n+δ heads and n-δ tails, where δ is (IIRC) sqrt(n/2). Going much away from that becomes infintessimally unlikely.
Probability is a subject famously easy to get wrong, so be careful with what I'm about to suggest: I *think* you could argue that in the moment prior to the inflation epoch spreading everything out just enough that pair production stops*, any given particle in our horizon is a coin toss of matter or antimatter.
Number of observed atoms in the universe is about 6e79 (http://www.wolframalpha.com/input/?i=how%20many%20atoms%20in...), so 6e79 = sqrt(n/2) -> n = 7.2e159 due to protons, and the same again for electrons; as we don't see significant signs of antimatter, any around must have annihilated a long time ago, so in this scenario we should expect to see ~7e159 (red-shifted) photons from the supermajority of particles which have annihilated.
It's outside my field to know how that compares to cosmologist's observations.
* won't that be at different times for protons/neutrons and electrons?
I can't get good answers on the expectations for either "why are protons and electrons counts the same" or "what is the observable consequence if they're not?"
It seems to have caught on, but one could still doubt its applicability to all phenomena at all scales.
The observable universe is the only true sphere.
The observable universe is expanding into the unobservable universe.
What would be interesting is to run a diff on the cosmic microwave background and the pictures from the James Webb space telescope to figure out where the true centre of the universe is, and derive the poles from there.
But then, what is the universe? One way to think of it is to imagine that every galaxy has at least one intelligent species with their own observable universe. The universe is the sum of all observable universes. The very nature of how to sum them together, what it means to combine multiple sets of thing which include items that don't exist relative to other items in the set, is a question we can't really answer yet. Because of this, even a question like the size of the universe is unknown, and even the question of if more of the universe exists outside of the observable universe isn't simple to answer and gets into the nature of what it means to exist. If someone exists in the universe, but not in the observable universe, it becomes an instance of Russell's Teapot.
https://cds.cern.ch/images/CERN-HOMEWEB-PHO-2022-023-1
Observing the edge is effectively looking back in time, to see the conditions of the universe closer to the time of the Big Bang.
New telescopes keep expanding that edge, and new particle colliders (such as those at CERN or Fermilab) keep "bashing 2 rocks together to make fire" - recreating the conditions of the Big Bang to see what comes off.
What I'm not sure about is whether the speed of light (assumed to be constant) is correlated with the size of the observable universe. Perhaps a physicist could shed some light on that question. Relativity means that galaxies that are moving at the speed of light away from one another (one travelling at c, another travelling at -c) have a relative velocity of higher than the speed of light (|c| + |-c| = 2c).
There's also the theory of the One Electron Universe, which I quite like (though that reveals my bias as an electronic systems engineer). Perhaps what we see is the One photon universe. https://en.wikipedia.org/wiki/One-electron_universe
Hopefully this rambling makes sense to someone!
In GR curved trajectories lead to "weird" observations. For instance, I'd expect the side of the remote galaxy that is closer (visually, for you as an observer) to the center of your galaxy to be gravilensed slightly more than the other side. Because the effect is non-linear, it does not just compensate when sides are reversed.
P.S. Not claiming this has any significant effect on the described phenomenon, just that mirror symmetry does not apply.
Instead of thinking of it like spin, think of it like heads or tails. Both are binary measures and frame of reference doesn't matter. For example if you're flipping a penny on a glass table and someone is looking from the bottom, they'll see the same ratio as you.
In a fair universe you'd expect pretty much a 50/50 heads/tails clockwise/anti-clockwise outcome. But instead we something like 66/34 or 75/25. The actual direction of spin doesn't matter. The fact the measurement is unbalanced does.
With that said, when the universe was younger things were way way closer so would it be possible for things like very early massive quasars to inject powerful magnetic fields in the otherwise dark universe at this time and bias matter falling into galaxies to one direction or another?
Real science will be when they survey the entire sky, with many small deep-field images.
There are ongoing debates whether the actual Entire Universe is infinite or not.
That said: I'd wait a bit here. This is a single-author paper by a non-astronomer (he's a CS professor). The sample size seems small (N=263), and the measurement coarse (he's just bucketing galaxies into "rotating in the same/different direction as the Milky Way"). And the technique may be too novel for its own good. The gold standard here would be to look at differential redshift, but all he's doing is applying a ML filter to detect the "twirl" direction in the image of the spiral galaxy. Which... might be amazingly effective or might fall on its face because of bugs in the filter.
But the signal seems strong, though (158 vs. 105 galaxies in each direction).
Basically, I'd wait a bit for someone to try to replicate with more data and more conventional measurements.
Let alone all other possibilities combined.
https://academic.oup.com/mnras/article/534/2/1553/7762193
https://ui.adsabs.harvard.edu/abs/2021ApJ...907..123I/abstra...
https://ui.adsabs.harvard.edu/abs/2017MNRAS.466.3928H/abstra...
>Take his claims about JWST as an example. In 2024 he wrote a paper about some early data, claiming to find more galaxies rotating with the Milky Way. He claimed based on a sample of just 34 galaxies that the signal was significant. Now he has looked at a wider dataset of the same area, which should allow him to verify his analysis. But it shows exactly the opposite, more anti. So he writes a paper saying this new result is definitely significant but doesn't reflect on the fact he has written two papers which contradict each other. He has failed to reproduce his own result. The take away is that his results are not as significant as he claims. He's also looking at a tiny area, and nearby galaxies can have correlated spins. He doesn't take this into account either. There are multiple JWST fields in different directions he could examine in different directions to test his claims, there are two JADES fields, but he only publishes one.
>I do wish the MNRAS editors would take measures to stop publishing low quality claims like this without more robust review. If you look at the text, it’s largely repeating results from his old papers. There’s very little discussion of the new results.
source: https://www.reddit.com/r/cosmology/comments/1ja9i53/the_dist...
The question starts to become very philosophical if there is a backup system for this universe. Everything being saved, for eternity, in infinite time. It would require very advanced computational power and storage, but it would probably work in binary (but that's just the kind of thing a computer engineer would say).
Maybe, though, the observable universe is rotating clockwise around a centre that is in the unobservable universe, and time is just a measure of how many rotations have been made since the Big Bang.
Im thinking: what if there are a bunch of massive objects like black holes in certain directions that are causing the light to bend in a certain way. So what would normally be light coming from the top of the galaxy plane, is actually light reaching us from the bottom of that plane. Would this slew the distribution of the spin one way - I don’t know.
The equation is on Wikipedia. https://en.wikipedia.org/wiki/Lorentz_factor
The terms are: v is the relative velocity between inertial reference frames, c is the speed of light in vacuum, β is the ratio of v to c, t is coordinate time, τ is the proper time for an observer (measuring time intervals in the observer's own frame).
If we could compare the time as we know it (based on the SI unit of seconds using an atomic clock) against the time at the singularity at the centre of the universe, we could figure out whether we're in a black hole, whether we're at the event horizon, or whether we're outside.
But we would have to assume space is a vacuum, which isn't entirely true.
*) The article is from March 17.
Trying to see beyond the edge would be like trying to peer out of a black hole. It would probably look blue, like Cherenkov radiation. (but I'm biased, due to having blue eyes).
If the Entire Universe is infinite, then it's eternal in time. And then we get philosophical again.
While I agree with your correction and this always bugs me, the common usage of the phrase "begs the question" seems to have become synonymous with "raises the question", as opposed to what I understand to be its former — and perhaps original — meaning which was associated with the informal logical fallacy by the same name.
And yes, I'm familiar with Dawkins' famous retort when someone asked how magnets repel things.
I don't think the universe is considered to have any significant rotation, however. Is this due to scale for us to measure, and/or having nothing external to compare against?
But there is no reason to think that the universe has a net rotation. It could have one; you don't need a frame of reference to detect rotation. (The same way you feel centrifugal force.)
It would be huge if it were shown to have a net rotation. So huge that I take this claim with skepticism until heavily confirmed.
But what could possibly happen other than they act like all other physical objects do? It boggles the mind to think how broken physics would have to be to accommodate a second correspondence principle for the big-but-not-too-big scale...
I feel like maybe I'm misunderstanding your sentiment, because this seems like a basic shared fact: a clock anywhere in the universe is still a clock.
So it’s a similar question. Where does this asymmetry come from.
Of course as an arrogant computer scientist I think they're downright kooky for not basing it on the galaxy, but ce la vie. Presumably there's one of those too, and this just wins for boring social inertia reasons as much as for any technical ones.
image: https://geoscienceaustralia.github.io/ginan/images/ICRF-75pc...
wiki: https://en.wikipedia.org/wiki/International_Celestial_Refere...
Of course this doesn't really matter for the above musing since top/bottom would purely be conventional based on our viewpoint, but otherwise illuminating on the issue of understanding rotation directions across the universe.
"We conclude that the hemispherical power asymmetry still remains as a challenge to the standard model." [1]
The density makes the scale recursion less mysterious.
The visible universe is redshifted and galaxies are getting further and further away. So jumping straight to “we are in a black hole” is weird
It is far more plausible that there is some coriolis like spinning effect in a higher dimension, even if the universe is flat it could have similar effects to how the earth’s spin makes cyclones all spin in the same direction.
Problem solved. Next?
It should be fairly easy to determine the rotation direction of any (spiral) galaxy we can see, based on reasonable assumptions about the relationship between rotation and the configuration of the spiral arms. There should be thousands or millions of visible galaxies for which this could be determined (out of the estimated 2 trillion galaxies in the observable universe). Perhaps I'm missing something, but why bother reporting a result from such a tiny sample?
It should also be possible to derive more detailed information that just clockwise vs. counter-clockwise. The rotation of a galaxy defines a direction (the galaxy's rotational north pole) and a point on the surface of an imaginary sphere. This could be determined by the galaxy's apparent rotational direction, its orientation, and its position in the sky. It would be interesting to see a plot of those points. In principle, they should be random. (If the points spell out "Go stick your head in a pig", I'll be very sorry that Douglas Adams didn't live to see it.)
Just because something is untestable today doesn’t mean it will be for all time. However, the untestability problem has started to creep much more deeply into cosmology and high particle physics in particular - our technology and models aren’t staying enough ahead to provide a lot of fertile testable ground.
A statistically unlikely arrangement of cosmic objects relative to earth only - earth in particular, violates not just the properties of the big bang but "the cosmological principle" and common sense. It's a garbage theory, a headline that makes a math person just have a "how stupid do they expect the average person to be" reaction.
Is it really your honest position that everyone has been doing cosmology wrong and you would have known better?
Similarly, the dynamical spacetime around a black hole not near any other black hole can couple with quantum fields -- even fields in a no-particle "vacuum" state as measured by an observer, for example one in orbit around the black hole -- with the result that Hawking radiation is produced.
Both gravitational radiation and Hawking radiation carry away energy (in the sense of ability to do work, per the "sticky bead" argument) from the environment immediately around a black hole. This in turn means that the horizon radius will be less than it could be.
So as a Hawking-radiating isolated black hole will tend to shrink (if it's not fed by hotter cosmic microwave background radiation, for example), the mass of a post-merger binary black hole will be less than the sum of the unmerged binary.
Just because things can't cross from the inside of a black hole horizon to the outside doesn't mean the horizon is always the same -- the horizon can grow and shrink dynamically when interacting with other self-gravitating bodies, with matter like dust or starlight, or with "the quantum vacuum".
I'm not. I was unable to substantiate that anyone named Dawkins, Richard or otherwise, made or is popularly associated with a comment about magnets. What was the retort?
If you take the approach you describe, I think you'd have incorrectly dismissed the observation that distant continents look as if they could fit together like jigsaw pieces, as it implied the impossible theory of continental drift. Isn't that just the same sort of outlandish, clearly ridiculous observation as "there's an asymmetry in the way galaxies rotate"? Except of course that one observation is correct, and the other isn't. You can falsify it just by checking the observation, rather than dismissing it out of hand as impossible.
Edit to add: maybe a better comparison would be to the violation of parity conservation in the weak force, as proposed by Yang and Lee, although I just learned from wikipedia that the actual experiment was performed by Wu. If you think that isn't a valid analogy, I'd be really interested to learn why.
If find this question fascinating. Matter can only ever exist with respective anti-matter. Question is where has all the antimatter gone? Are there processes were it does indeed behave different from matter? So where is it? Since a photon and antiphoton are the same and do not absorb each other, we should be able to see it, shouldn't we?
I still want to believe in the antimatter universe where there is some evil twin of mine.
https://en.wikipedia.org/wiki/Sundial#In_the_Southern_Hemisp...
So "clockwise" is because the Earth's axis of rotation about itself is not too far from perpendicular to its orbital plane of rotation around the sun, and because the Earth rotates counter-clockwise from the perspective of someone hovering above the planet's north pole. This is the right-hand rule.
Earth's axis of rotation (and orbital plane) is fairly well aligned with most of the round bodies in the solar system, except notably for oddball tilted Uranus and anti-aligned Venus (and the pretty different orbital planes of the minor planets like Pluto and Eris).
The sun's north pole (following the right-hand rule) and south pole do not point to anywhere particular in the galaxy, and its axis of rotation is highly tilted with respect to the axis through the central bulge of the Milky Way. A nice diagram that seems to have originated from the European Southern Observatory: <https://www.physicsforums.com/attachments/motion-of-earth-an...>
Most disc-like structures we've found tend to be randomly oriented compared to each respective host galaxy's polar axis.
For spiral galaxy rotations we have much better data from mostly edge-on views because we can measure the doppler shifts of molecular clouds at their margins; the advancing side will be less red-shifted than the trailing side. Spectral lines also broaden with the magnitude of rotation. AFAIK there is nothing at all unexpected about the distribution of trailing vs leading edges on our sky; the mystery is in the magnitude of the rotation of these outer gas clouds compared to things like their galaxy's apparent optical brightness or other markers of mass.
Also fun is that for elliptical galaxies, these gas clouds don't rotate around the equatorial bulge of those that have them. They instead tend to move mostly radially deeper and shallower within their host galaxy.
So if galaxies don't choose the rotation of their internal components like star systems or radio-loud objects like pulsars and relativistic-jet-equipped black holes, why (accepting for the sake of this argument that this garbage paper is correct about there being a bias in face-on spiral galaxies) would a distant galaxy affect us more than our own?
But we observe a bias. Now, that could just be chance — but it's more likely that we've missed something somewhere so our assumption was wrong. One specific possibility is that the universe has an intrinsic spin, which might be because (per the article) we're inside the event horizon of a black hole which is spinning.
Also, yes: we are at the centre of our observable universe.
We can say that any particle inside the horizon is inevitably headed to the center. (That's why we can't say any more: no other information can escape.) That does lead to a problem in that all of the mass would be concentrated at a single point at the center, whose density is division-by-zero.
But I wouldn't put too much weight on that. We already know from quantum mechanics that there isn't really any such thing as a "point". The math is still a problem, but the solution almost certainly lies in that direction.
Are you sure you understood the comments completely?
It’s my honest opinion that anyone assuming away phenomena like turbulence, without credible proof, cannot be relied upon to have accurate insights.
So yes whenever I do have better insights, than by definition that’s more than 100% of the population who do not.
This is generally true, but such ideas are kept outside the realm of science until they are. In this case specifically, all our knowledge points to this remaining untestable as it would require FTL travel which is on par with violating conservation of energy or time travel. It even allows solving the halting problem (Turing machine in timeloop until it halts, you outside of the timeloop can then check if the Turing machine in the timeloop ever left it).
It is entirely possible that there are things which are true which science cannot verify because of the underlying philosophy by which science operates. Things that exist outside of the observable universe, if FTL travel is truly impossible, would fall outside the realm of science.
>The mere fact that two observers have different observable universes indicates it is indeed an illusory artifact.
Do they? The nature of the observable universe is that, if you can communicate with someone else, any information they can receive and pass on to you is part of your observable universe as all information travels at the speed of light or slower. If they can receive information and cannot pass it on to you, they are not part of your observable universe any longer and no longer exist (exception if FTL interactions are discovered). Thus the only observers that exist in a way you can interact with, can make any testable hypothesis concerning, and thus can be considered by science, are observers in your observable universe.
The observable universe is defined as natural light reaching us. It says nothing about repeaters. If someone id at the edge of your observable universe they could still send you a message. They’re observable universe would necessarily include light that wouldn’t reach you due to expansion. Of course, it is possible we’re within a black hole or some other weird space time geometry in which the universe folds in on itself in which case it is possible the observable universe is the universe. I’m not saying that’s impossible since we don’t know. I’m simply stating my Bayesian priors based on my understanding of the evidence collected so far about the CMB and what it and the theoretical models we have suggest. It doesn’t make other theories less valid, it just means where I’d make a wager if I had to. As you say, right now it’s not capable of being a scientific theory and it’s a stretch to even be called a hypothesis.
Still, this is just a reversion to our natural state where we have philosophical ideas grounded in the best knowledge we have trying to find ways to unlock the secrets, not unlike ancient Greeks. We might succeed or we might not but I still think it’s a scientific pursuit grounded in the scientific method in some way. For example, we have no way of really confirming whether our models are correct about estimating the distance to stars. Still, we think it’s true enough because it works locally. Science is and always has been a fuzzy endeavor of truth seeking and only local models of simple interactions have a “nonexistent” amount of error.
If you were inside a black hole you wouldn't be able to see light from "deeper" because it wouldn't be able to travel towards you.
This is not what we see within the universe, so I don't think we can be inside a black hole
I don't think it does once accounting fully for relativity (and assuming perfect sensors, so the idea of information being too redshifted to be detected isn't a factor until that information no longer exists within the universe, and immortality of participants, and near light speed travel).
Say Alice and Bob can communicate X years apart at near C speed. At any time, Alice can jump on a spaceship and reach Bob in ~X years. Therefore, anything in Bob's observable universe at that time counts as also being in Alice's observable universe.
If the distance is so far apart that one day space will expand too fast, then there is a moment where Alice stops being able to travel to see Bob ever again. At that moment, Bob's observable universe is now distinct for Alice's, but they also can no longer communicate.
Bob could get on a spaceship going near C away from Alice and access information that is outside of Alice's observable universe, but Bob only crosses that barrier when he moves far enough away from Alice that he exits her observable universe. (Technically I think you get some sort of infinite sphegettification of Bob leaving as he crosses Alice's observable universe's event horizon, where he never fully leaves and sends back photos that become more and more red shifted until their wavelength equals the diameter of the observable universe.)
So Bob has an observable universe that is different from Alice's, but it is predicated on him exiting from Alice's observable universe to access it. Either he accesses it and stops existing to Alice, or he doesn't access it and eventually it falls out of what he can possible access. The only part he can access and still communicate back to Alice is the part within Alice's universe. It is a bit like a superpower to turn invisible only when no one is looking... sorta kinda...
Given enough time, Alice and Bob either drift together until they clearly share the same observable universe, or eventually drift apart to the point expansion of space shifts them into two separate unrelated observable universes and they stop existing relative to each other.
Theory or data/observation is a sort of layered thing. The lowest data level is the data that the Webb or whatever telescope gets, then you have the theory that what's being represented in galaxies and you have all suppositions of standard cosmology and in that you have a posited theory that galaxies as viewed from earth rotate in a "given direction".
The thing about this theory/observation/whatever is that it's a pattern that, if true, would only be visible on earth (or in vanishingly small area relative to the claimed area of the pattern). If such a thing were happening, it wouldn't just contradict current physical laws. It would contradict the paradigm science has had since Newton that physical laws apply uniformly throughout the cosmos and especially that the earth isn't the "center" of the universe. The observation of continents fitting together or violations of parity conservation aren't analogous because they involve things that can be meaningfully observed anywhere.
All this is to say "extraordinary claims require extraordinary evidence". As far as investigating. I could or someone could, spend the effort needed to investigate this. But science actually should have one level of claim+evidence that's "interesting, let's investigate" and another that's "oh dear, that's really crank stuff and you'd need to truly vast evidence before I'd even look". Other science would be overwhelm by bullshit.
I’m willing to concede I don’t know enough about the actual math of cosmology and relativity to say. How certain are you in your reasoning? I’m willing to admit either case could be possible and neither is a testable prediction at this time but maybe my first principles reasoning is outright flawed?
It seems impossible for this to add to your argument.
I don’t see any obviously titled ones on Google Scholar, such as proving it’s impossible for turbulence to “introduce net angular momentum”.
But.. no, I don't have a convenient citation for you. And at least for the "angular momentum is conserved thing", I'd be surprised if you'd find a google scholar paper, this is early GR
