Astronomer Claims 'Direct Evidence' of Gravity Breaking Down (vice.com) 118
A scientist has observed a "gravitational anomaly" in certain star systems that could potentially upend a fundamental assumption about the universe, according to a new study. Motherboard reports: Kyu-Hyun Chae, an astronomer at Sejong University, has now put these models to the test by analyzing the accelerations of stars in 26,500 wide binaries located within about 650 light years of Earth using imagery captured by the European Space Agency's Gaia observatory. Scientists have previously searched for signs of modified gravity in these systems, but Chae took the next step by developing a new code that could account for special details, like the occurrence rate of so-called "nested" binaries in which the loosely orbiting stars also have close stellar companions. The new data suggests that when the gravitational accelerations of these stars slip below one nanometer per second squared, they begin to move in ways that are more aligned with MOND models than by the standard model. Chae said the findings offer "direct evidence for the breakdown of standard gravity at weak acceleration" and reveal "an immovable anomaly of gravity in favor of MOND-based modified gravity," according to a recent study published in The Astrophysical Journal.
In the new study, Chae reports what he calls "clear evidence" that the movements of binaries at points of weak acceleration seem to sync up with a particular MOND prediction known as AQUAL, according to the study. This discovery suggests that the standard view of gravity cannot account for these motions at low accelerations, which may inspire scientists to rethink aspects of Newton's inverse square law of gravity and Einstein's general relativity, as well as the necessity of dark matter. "Because a large amount of dark matter -- six times the baryonic or ordinary matter based on the standard model -- was required by assuming that general relativity was valid in the low acceleration limit, such a need for a large amount of dark matter is no longer valid," Chae explained. "This does not necessarily preclude the possibility that new particles, such as sterile neutrinos, could not be found. But, it is clear that there is no need for as much dark matter as required by general relativity." "When the results started to show up from my new and more reliable code, my initial reaction was that it was unbelievable," Chae said in an email to Motherboard. "I was feeling like I was dreaming. It seemed so unreal. This is because my results did not match any previous results."
"Several previous results even claimed that the standard gravity was preferred by wide binaries data including Gaia DR3. One group has been claiming an anomaly for some time, but the anomaly seemed not to match well the predictions of existing modified gravity theories. However, those previous studies did not self-calibrate or fully take into account the amount of hidden nested binaries."
In the new study, Chae reports what he calls "clear evidence" that the movements of binaries at points of weak acceleration seem to sync up with a particular MOND prediction known as AQUAL, according to the study. This discovery suggests that the standard view of gravity cannot account for these motions at low accelerations, which may inspire scientists to rethink aspects of Newton's inverse square law of gravity and Einstein's general relativity, as well as the necessity of dark matter. "Because a large amount of dark matter -- six times the baryonic or ordinary matter based on the standard model -- was required by assuming that general relativity was valid in the low acceleration limit, such a need for a large amount of dark matter is no longer valid," Chae explained. "This does not necessarily preclude the possibility that new particles, such as sterile neutrinos, could not be found. But, it is clear that there is no need for as much dark matter as required by general relativity." "When the results started to show up from my new and more reliable code, my initial reaction was that it was unbelievable," Chae said in an email to Motherboard. "I was feeling like I was dreaming. It seemed so unreal. This is because my results did not match any previous results."
"Several previous results even claimed that the standard gravity was preferred by wide binaries data including Gaia DR3. One group has been claiming an anomaly for some time, but the anomaly seemed not to match well the predictions of existing modified gravity theories. However, those previous studies did not self-calibrate or fully take into account the amount of hidden nested binaries."
maybe (Score:3)
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The same can be said for every single model based on dark matter.
Re: maybe (Score:3)
I mean, the headline is sensationalist bullshit. What heâ(TM)s found is evidence that at low accelerations gravity either isnâ(TM)t as strong or doesnâ(TM)t work. That being evidence of MOND being correct Iâ(TM)m not so sure about. The evidence that MOND isnâ(TM)t correct seems too huge. In particular, the fact that gravity seems to behave differently in different galaxies seems to make dark matter a much better explanation. Specifically, thereâ(TM)s at least one galaxy we
Stronger [Re: maybe] (Score:2)
I mean, the headline is sensationalist bullshit. What heâ(TM)s found is evidence that at low accelerations gravity either isnâ(TM)t as strong or doesnâ(TM)t work.
quick correction: the opposite. The result says that the observed gravity at the low-acceleration limit is stronger than predicted.
That being evidence of MOND being correct Iâ(TM)m not so sure about. The evidence that MOND isnâ(TM)t correct seems too huge. In particular, the fact that gravity seems to behave differently in different galaxies seems to make dark matter a much better explanation. Specifically, thereâ(TM)s at least one galaxy we know of where the baryonic matter seems to be all the mass needed to explain the speed of its starsâ(TM) rotation. Further, we see gravitational lensing in areas of space with no baryonic matter.
Yep. Interesting. I'm a little dubious based on the fact that previous analyses of this data set did not see evidence of (slightly) anomalously strong acceleration, which makes me wonder about how reliable the corrections are which he made to the data in order to uncover the effect. But that's something for the experts in the field to look at.
It's not quite true that the resul
Re: Stronger [Re: maybe] (Score:2)
It'd be interesting to see, for example, if the MOND flavor he suggests (or any other, for that matter) explains the difference in odd and even peaks in the power spectrum of the CMB.
Classically, since MOND predates the CMB power spectrum and failed to predict that, some MOND versions retroactively add new fields to the universe's content. So while they don't call it that, they're effectively reintroducing Dark Matter, the very thing MOND tried to do without.
On another note, if the observations of this rese
Re: Stronger [Re: maybe] (Score:2)
Whatever dark matter hypothesis they came up with would have to add anti-gravity somehow. MOND gives a way to explain the existence of extra gravity across the whole universe. If you find a galaxy that doesnâ(TM)t need extra gravity (which we have), then for MOND to be correct you now need a way to subtract gravity from that galaxy somehow. Thatâ(TM)s not likely at all when compared to âoethereâ(TM)s just extra mass we canâ(TM)t seeâ.
Personally Iâ(TM)m a fan of fuzzy da
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Since the measurement, if confirmed, says that low accelerations (ie, at high distances) are (very slightly) greater than expected, an explanation using unseen matter doesn't require antigravity, but posits additional mass between the two stars.
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Right? I keep hearing about the need for 'dark matter' but every few months someone either finds further evidence that it is bullshit
Huh? I've never see any evidence given that the dark matter hypothesis is "bullshit", and there have been some very good observations in support of the hypothesis (primarily from gravitational lensing), although we'd like to actually find it before saying "we nailed it". What we do see every few months is alternate hypotheses being touted (almost always MOND or variants of the MOND hypothesis).
or uncover even more of the supposedly missing mass in our universe. And all the dark matter proponents simply say 'we will eventually find proof that it exists outside our math. Someday. Maybe. Won't you fund us more?'
Right now dark matter is still the leading hypothesis to explain galactic motion. The alternative hypotheses have
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The entire idea of "dark matter" and "dark energy" is because it is needed to fix are lack of understanding of the entire issue around gravity. They people who promote those theories are invested in research around it, and you won't every hear them say the emperor has no clothes, even though it may look like that.
Dark matter/Energy has been made up to fix the lack of understanding. Maybe us not understanding gravity completely might be a simpler/cleaner answer than making up something that in all the year
Re:maybe (Score:4, Informative)
Dark Matter and Energy are not hypothetical explanations, just the names we gave the problem of discrepancies between our models and observations, there's nothing to prove there. The actual hypotheticals to be tested are things like axions, wimps, MOND, a cosmological constant, etc...
Re:maybe (Score:5, Informative)
We'll know soon enough. Chae's code and data is sitting right over here [zenodo.org]. He's certainly not hiding the ball.
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Yeah, sure. (Score:2)
Also, room temperature superconductors, tired light, aliens in chains, etc.
You know, Slashdot doesn't have to propagate every claim anyone makes. If it's an actual big deal, we'll find out. 'Til then it's just noise
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Loosen your corset, Grasshopper. These stories are an endless fount of amusement.
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The ones that are obvious frauds, or can't be tested by anyone else, yes. But this is based on clear evidence and the code is visible. So it's definitely "news for nerds" even if it's not your particular area of interest.
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Also, room temperature superconductors, tired light, aliens in chains, etc. You know, Slashdot doesn't have to propagate every claim anyone makes. If it's an actual big deal, we'll find out. 'Til then it's just noise
This one is actually in a peer-reviewed journal.
That doesn't mean it's right, but it does mean it's worth taking seriously, not just a wild claim with no real evidence.
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Stick to MSNBC for news then.
People being normal is the opposite of progress.
Only oddballs venture outside the norm.
Hopefully a step to understanding gravity (Score:2)
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Not down a gravity well as this seems to apply when acceleration is very small.
Probably (Score:5, Funny)
Re: Probably (Score:2)
Mod parent up!
Dubious. (Score:5, Informative)
Gravity Breaking Down
breakdown of standard gravity at weak acceleration
MOND-based modified gravity
This all seems fine and dandy, but... Is MOND a theory about modified gravity at all? I thought MOND (which means Modified Newtonian Dynamics, by the way) attacked not the Newton's law of gravity in particular, but the more fundamental Second Newton's law of mechanics, about the linear relationship between force and acceleration. In short, the MOND theory has nothing to do with gravity. If it had, it would be called MONG, instead of MOND. The unfortunate (?) fact that Isaac Newton's name is associated with both the laws of gravity and the fundamental laws of mechanics has probably confused some journalists and maybe (I hope not) some physicists as well.
Re:Dubious. (Score:4, Informative)
Is MOND a theory about modified gravity at all?
According to the MOND Wikipedia article [wikipedia.org] "MOND is an example of a class of theories known as modified gravity, [wikipedia.org]"
(I am not making any claim personally here, I had never heard of this until 15 minutes ago)
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Is MOND a theory about modified gravity at all?
Yes.
Very Cool (Score:1)
Interesting, I wonder how much processing it requires to do algorithmic model searches likes these? I would also like to know who much searching he had to do before he found an anomaly.
Hopefully with James Web and the fact that there are uncountable galaxies, this will make it very easy in the future to test new theories and find anomalies that point out edge cases in our theories of gravity. Maybe even unlock the secret of efficient space travel.
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I wonder how much processing it requires to do algorithmic model searches likes these?
Kyu-Hyun Chae has been using 128 cores/threads to run his Python multiprocessing software. So an EPYC or XEON machine with likely two or four CPUs. Not much really. You could by one yourself for less than $20k.
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No need for a fat server box with multiple sockets. Even a single Threadripper from 2020 can run 128 threads for like $2k, and that's only a consumer grade CPU.
By 2023, you can get 64-core SBCs...
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By 2023, you can get 64-core SBCs...
Where? It's 2023, in case you're somehow unaware.
And even so, the cores in question aren't tiny little just barely super-scalar ARMs with next to no cache, saving battery power.
On the other hand, he's doing this in Python... Might be that you could do the same in a fast language and 16 cores.
Re: Very Cool (Score:2)
The python libraries used are very likely the specific physics libraries and floating point libraries, and they are mostly written in C and compiled to machine code. Good luck improving the runtime of that code in another language.
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A sleeping thread is not running. Heck, it's not even runnable.
A Shortfall of Gravitas (Score:2)
Let me guess (Score:5, Funny)
The observatory is located in a basement in downtown Seoul, South Korea?
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I am in Seoul right now, will check basements for new discoveries.
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If I read the summary correctly, the observatory is out in space, the administration offices are in Europe. This guy was doing analysis of publicly reported data.
When my results do not match, I check my results.. (Score:3)
... almost always it is my mistake...
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I'm reminded of my favorite ST:TNG quote [youtube.com].
Linear term? (Score:3)
Quantization (Score:2)
So there's a linear term in the gravity equation, and it only shows up when the quadratic term becomes really tiny?
More likely the universe is quantized at some small scale, and we're seeing quantization effects of what we think are real numbers (in the mathematical sense) are actually rational numbers of quantized measurements.
If the universe is based on rational numbers (essentially - any dimension is quantized by integer measurements of some very small value) then the universe is computable. The results of any interaction can be computed from a sufficiently fine measurement of the parameters of the start position, wi
Re: Quantization (Score:2)
I recently read an article about someone using Intuitionist mathematics (no real numbers) to prove that you cannot compute everything from a know starting position, hence time is irreversible.
Can't find the article right now but I think it has some bearing on your statement.
Interesting (Score:5, Interesting)
The highest probability would seem to be buggy code or flawed assumptions.
However, MOND is an interesting concept and it's entirely possible that both MOND and conventional Dark Matter exist. Dark Matter seems to be all but certain, but there are cases where there's no detectable Dark Matter where models say there should be, and predictions for gravity are all wildly wrong at the quantum scale. The idea that current models of gravity, or its effect, need tweaking where gravity is very slight seems reasonable enough.
Having said that, physics at this level isn't "reasonable" and continues to kick common sense in rather painful areas, so just because the models seem to break down in very low gravity doesn't necessarily mean what it seems to mean. Physicists are paid to study this sort of stuff precisely because nobody is going to produce an inspired guess on social media that's worth a damn.
Still, if they discover that you need MOND to get gravity to behave properly under these sorts of extreme conditions, IN ADDITION TO having Dark Matter, it would not at all shock or surprise me.
Re:Interesting (Score:5, Interesting)
So, when you've got 2 theories that both don't quite fit observations, both require a manually tweaked scalar field that no other theory explains, do you pick the one based off of Newtonian dynamics (easily disproven below the classical limit), or the one based on the equivalence principle? (that pesky thing we've yet to disprove in any manner at all)
The answer is the latter. And that is why MOND is not the predominant explanation for gravity.
MOND corrected to account for relativity is a shit show, with different a0 values required for every fucking galaxy.
If there is indeed something funky that happens to gravity at low accelerations, it isn't caused by MOND, at least not as formulated.
Re: Interesting (Score:2)
MOND doesnâ(TM)t fit observations even with dark matter. Weâ(TM)ve observed at least one galaxy where baryonic matter is all thatâ(TM)s needed to explain the rotations speed. That means that MOND predicts too much acceleration in that galaxy, and no amount of adding dark matter is going to fix it.
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Yeap, If the models for how stuff is created are off, there could be smallish black holes/older neutron stars not consuming anything (so invisible) and/or any other number of cold non-luminous objects around that we cannot see and aren't counting (except via gravity) especially if said objects are not bound to a solar system that you can detect oddities in the orbit of the luminous objects in the solar system.
Dark matter is still tweaking their models and still don't always work right without adjustments,
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The gravitational distortions are cold (having non-relativistic velocities) and non-baryonic.
There is room in observations for some fraction of the measured mass being baryonic (black holes and neutron stars that don't fit theory), but not nearly enough to account for the observed large-scale curvature of spacetime.
The reason DM seems as it does to you is because you are ignorant to the evidence for it being non-baryonic.
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Given how much indirect data mass approximations use(both those based on gravity/inertia and on light) it could easily add up to 300% error.
The quantity- absolutely.
But you missed the point, no error bar gets rid of the observational evidence that the missing mass must be cold, and non-baryonic.
Lambda CDM is absolutely falsifiable (and is constantly under attack- which is good)
Lambda CDM is just a model. It has implications on the contemporary distribution of DM, but in no way does it rule out DM-less galaxies.
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To see what baryonic is and what isn't you'd need a collider.
Or a telescope. It's that simple.
The gravitational lensing of DM is immediately apparently and calculable. There's a lot of unknowns after that, but one thing isn't- the lensing isn't caused by ultra dense objects.
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Whatever creates the gravitational distortions we observe isn't dark. It's invisible. It's non-baryonic.
Re: Interesting (Score:2)
Is positing different amounts of dark matter in every galaxy different from positing a different a0?
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Newtonian Dynamics is correct only above the classical limit.
Below it, it's flat out wrong, and demonstrably so. Very, very fucking easily.
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I think you get above and below wrong.
No.
For everything that is relevant in Space flight: Newton is just fine.
Yes.
If you you use one way of calculating something, and then another way of calculating the same thing: none of the ways is *wrong*. One might be more accurate, that is all.
Inaccurate is wrong.
But be my guest: show us how you calculate a flight from Earth to Mars using Newtion mechanics and then Einsteins. Same trajectory of course. And a rough calculation how much that is in fuel molecuels would be nice, too. Does not really matter if you are of by 10 or 20 magnitudes: regarding the difference of fuel molecules used.
No, because you have created a limiting qualifier that excludes the areas where Newtonian dynamics is flat out wrong.
I can do the same: "Now try that trip at 0.9c"
And then explain to us, how one can be wrong and the other "less wrong" when both make you end up in the exact same spot. Give or take a few wavelength if light ...
No, because you have created a limiting qualifier that excludes the areas where Newtonian dynamics is flat out wrong.
So, what is your wild guess? Lets talk about fuel? Aka energy? We sent a rocket from Earth to Mars. You calculate it Einsteinain, I calculate it Newtonian: what is the difference in fuel usage? 10%? 1%? 0.5%? Or so close to zero that you can not judge who calculated it better?
I have a better example.
Calculate the orbit of Mercury using Newtonian dynamics over the course of a year, and then fly your very Newtonian-valid-velocity ship to where you predict it will be.
If your
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It will be exactly there.
It absolutely will not be.
The orbit of Mercury precesses.
The difference between Newtonian gravitation and General Relativity is 43 arcseconds per century, or 0.43 arcseconds per year, or 0.1035 arcsecond per orbital period (88 days)
The fastest trip to Mercury ever was Mariner 10, at 147 days, or 1.67 orbital periods, or 0.172 arcseconds of perihelion precession.
Mercury has an orbital aphelion of 69,816,900. That aphelion mapped to a circle around the sun (as the precession follows) has 438,672,512km of
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Dark Matter seems to be all but certain
It is possible I misunderstand things that others have discovered; however, I believe it is literally impossible for Dark Matter to actually exist as such. What I mean is this:
Dark Matter is a placeholder or variable to hold an unknown. Let's assume they assign the value of 12 to it (random easy number). That 12 is not necessarily a 12 at all. It could be 6+6 or 4x3 or 3+3+3+3 or even some exotic equation that ends up resulting in 12. 12 is just the placeholder. 12 is not 'real' in this regard.
Dark Matter d
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Sorry, but Dark Matter COULD be a unitary entity. I don't think there's any reason to believe it is, but AFAIK it could be. And in the absence of better ideas, people tend to strongly prefer the simpler one.
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Sorry, but Dark Matter COULD be a unitary entity.
You are, in theory, correct. I am wrong for excluding the outrageous. My apologies.
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The highest probability would seem to be buggy code or flawed assumptions.
Or (from the article)...
when the gravitational accelerations of these stars slip below one nanometer per second squared
...maybe they are just high if they think that they are getting measurement resolution down to the nanometer per second.
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The highest probability would seem to be buggy code or flawed assumptions.
Wait, wait, wait. Let's not discount a closed temporal loop caused by an antimatter explosion. That happens all the time.
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Ummm... what do you mean "matter". If you said "we detect apparent mass" I'd agree, but "matter"...well, that's an assumption. In fact the existence of matter at all may be an illusion, if I understand quantum field theory properly in this regard. But none of our detections of "dark matter" imply anything particulate, or if they do I don't know about it.
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"Matter" means fermions. The dark matter hypothesis attributes the missing mass to fermions. There are basicaly two options: (1) fermions that don't interact electromagnetically and (2) ones that do but are arranged in such a way that we can't see them. We've discovered examples of both: neutrinos, black holes, brown dwarfs, rogue planets, etc. However, even all together those don't seem to make up much of the missing stuff, suggesting that possibly there are one or more additional fermions out there that w
MOND has a certain Occam attraction. (Score:2)
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But astronomical data is so, so tricky.
So it was in Artistoteles' time.
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The most we can say is that the maths checks out and agrees with a lot of observations. And it can't explain some observations without something extra.
So... do we have direct proof of Einsteinian gravity?
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Sure, it was reasonable for a long time. Gravity comes from stuff, so if things are moving like there's more stuff but you can't see it, look for the weird stuff. But the longer you don't find
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Just like with Dark Matter. We see its effects in some data. It's not just galaxies. There's also LCDM.
MOND has been around for a while, and has made as much progress as string theory.
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Relativity is verified far past the point of what science considers a valid discovery, although it's accepted to be incomplete on small scales. Dark Matter is not itself a theory, it's a hypothesis based on theoretical interpretation of the data that has not yet proven out. MOND is a variation on theory that removes the necessi
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As for your goat example, if you conducted a valid scientific test on whether goat sacrifices cause sunrises, you would quickly prove the lack of connection when the sunrise is unaffected by the presence or absence of such behavior. If somehow there were a connection, it would take more time to establish statistically, but you
Re:MOND has a certain Occam attraction. (Score:4, Interesting)
FWIW, we know that either relativity, quantum mechanics, or both are wrong. We don't know how. Both pass every test we can throw at them, but the disagree about some predictions where we can't test them.
OTOH, both dark matter and dark energy may be fudge factors to allow relativity's gravity to work. Perhaps. And quantum mechanics has a few rocky places too. So we want a better, more encompassing, theory. Finding one that fits all the data, though, is a real problem. Everything so far has too much hand waving to take seriously.
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Michio Kaku's book Hyperspace has an interesting idea: there's a tension between newly developed forms of theoretical math and evolution of human intelligence/insight at a practical level. All the math for SR and GR existed (and was no small feat to develop), but it took an Einstein to have the fundamental insight into the nature of spacetime. Kaku suggests that in our modern era we have developed some highly esoteric math that so far has outstripped the ability of humans to practically apply it. Thus i
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Like the ether people thought was needed for fields to travel.
Gravity is not a fundamental force (Score:2)
Gravity is not a fundamental force like everyone seems to believe. Gravitic effects are the relative interaction of the space field and the time field interacting. It is rather like how electromagnetic effects are the relative interaction of the magnetic field and the electric field.
I understand if you do not believe my claims; however, if you accept the claim that gravity is indeed a fundamental force, then you will need to justify your belief in order to fully discard my belief.
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Gravity is the warping of spacetime though I've never heard space or time referred to as fields. They are affected by fields.
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If there is nothing. Then nothing exists. So 'something' has to exist for other things to exist.
I think it is safe to assume that in some manner, SpaceTime exists.
How does it exist? How is it expressed? I have no human words other than 'field' to describe it.
Pure conjecture with no basis in Reality: SpaceTime and ElectroMagnetic fields are created by energy in 'certain' states. The end result is something we call 'Mass'. Mass can show 'field' effects, despite not being classified as a field.
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This is an interpretation of general relativity, one Einstein wasn't a big fan of, incidentally.
In the interpretation, spacetime is the gravitational field, not the other way around.
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I once tried to put together a theory were gravitational attraction was caused by quantum uncertainty interacting with time slowing down where mass increases. So a distant observer would see it tending to spend more time (his framework) closer to a mass than distant from it, while in the framework of the particle it was spending equal times in both locations.
Well, I couldn't make it work, but I still think it may be the answer. And it explains why gravity is so weak.
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That is very interesting. It sounds like a valid path of pursuit. I hope you can work on it to deliver more details.
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Sorry, but if it's going to be done, someone else is going to have to do it.
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It is not Creationist reasoning; although it does resemble it.
If you tell me that you believe everything was 'created' and I tell you I believe everything evolved and then say, "You will need to justify your belief before you can fully discard my belief.", then what is really being asked for here?
Believing that Gravity is a fundamental force is an absurd belief... as is my belief that Gravity is NOT a fundamental force. What I am saying is, "Prove you are right and I will know I am wrong.".
I see absolutely
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It is the electro-magnetic force and the weak force that were first unified. The theory unifying the strong force with the electro-weak force has not yet been experimentally c
I'm not an astrophysicist... (Score:5, Interesting)
...but I've operated telescopes for hundreds or thousands of astronomers and astrophysicists, operated a range of professional astronomical instruments (by which I mean imagers, spectrographs, polarimeters etc. weighing from tens to thousands of pounds, not amateur gear), and taken a lot of data (for a collaboration including Saul Perlmutter, doing follow-on research to his Nobel-winning dark energy stuff). So I'm not unfamiliar with astrometry and with small red/blue shifts in spectra.
When I read this sentence:
The new data suggests that when the gravitational accelerations of these stars slip below one nanometer per second squared, they begin to move in ways that are more aligned with MOND models than by the standard model.
I want to know what instrumentation this guy is using that's capable of reliably measuring the gravitational accelerations of stars to sub-nanometer/sec/sec precision, with high confidence. That kind of precision and reliability is very impressive, if you can actually get it.
And if he's just crunching data from GAIA without any followup data-collection using some non-GAIA hardware, I want to know whether GAIA's own science team are claiming that kind of precision for their own data, and if so, with what level of confidence.
I'm probably going to have to read the paper... /sigh.
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So I read an article about a related paper, in which the Gaia folks say they've analyzed almost 3 years worth of data and determined that the acceleration of the solar system toward the galactic center is something like 0.23 nanometers/sec/sec. Which is very precise. But the wording there makes it clear that this is a calculated average rather than an actual observational measurement. That makes a lot more sense.
High precision? (Score:2)
At 1 nanometer/sec you'll be very vulnerable to any x-th order instrumentation issues and/or algorithm issues. You're talking about measuring stellar objects many light years away at scales of about 1 atom.
Are nested binaries just epicycles? (Score:2)
Gravity issues aside, is epicycle theory compatible with these galactic observations?
The inflection point is the key result (Score:2)
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It didn't actually. The first mentions of dark matter were sort of hazy calculations involving stars in our local stellar neighbourhood. Zwicky in 1933 observed that the Coma cluster seems to have more mass than would be inferred from visual observations. Galaxy rotation curves came last, in 1939.
Refresher course on Scientific Methods (Score:2)
See this video of Richard Feynman's lecture: https://www.youtube.com/watch?... [youtube.com]
isn't "dark matter / energy" the explanation ? (Score:2)
Didn't the terms "Dark Matter" and "Dark Energy" get created to address these unexplained aspects of gravity in astronomy ?
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but my question is are we just saying that there is the same anomalies but we don't like those placeholders any more ?
Extrodinary Claims (Score:2)
related to relativity breaking down? (Score:2)
or maybe this is a prelude to bans on faster-than-light travel breaking down, but only within observed sizes of the universe exceeding what is allowed by on red-shift estimates of farthest astronomically measurable (visible) structures....???
Or maybe this is just a prelude to breakdown of current physical "constants", etc...?
.
Bullshit Study (Score:2)
This is a bullshit study that's an excellent example of the sort of p-hacking you can do by tweaking a model. Expect future studies to show this is bullshit in two to three years. This is why we need preregistration as a prerequisite to being published.
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So,
It doesn't require the introduction of hypothetical dark matter.
Bullshit. Like MOND, it just needs less.
Re: (Score:2)
Re: (Score:2)
Note that this isn't an indicator, or a claim by me that EG is "wrong", only that it doesn't get rid of the need for non-baryonic cold dark matter (yet).
Re: In any case ... (Score:2)
Is absence of evidence evidence of absence?