EDIT: Let’s cool it with the downvotes, dudes. We’re not out to cut funding to your black hole detection chamber or revoke the degrees of chiropractors just because a couple of us don’t believe in it, okay? Chill out, participate with the prompt and continue with having a nice day. I’m sure almost everybody has something to add.
Dark matter. Sounds like a catch all designed to make a math model work properly.
You’re not wrong. According to the current scientific understanding of the universe, that’s exactly what it is. They just gave it a badass name.
Do you want slightly darker matter? Cause that’s how you get slightly darker matter!
Other way around, the math model worked fine without dark matter, and it was experimental observation that revealed DM. And yes, the term dark matter is a catch all by design because we don’t have a single theory on it yet.
Do you think solutions to dark matter are tied up in a unified GR + quantum mechanics theory?
I would be surprised. Quantum Gravity becomes relevant in very extreme energy conditions, while dark matter is relevant in the normal universe.
That sounds like it’s trying to take large scale phenomena and make them work on the quantum scale. What if the solution is the other way around: make modified quantum mechanics work on the large scale? (I guess those are effectively the same thing. You’d need a quantum gravity theory one way or another. Sorry, layman here. Just spitballin’ ideas)
The experimental observation did not reveal Dark Matter. Nobody has seen or proven Dark Matter, actually. That’s why it is called Dark Matter. The observation just showed that the math model was flawed, and they invented “Dark Matter” to make up for it.
My personal take is that they will one day add the right correction factor that should have been in the fomulas all the time.
Just like with E=mc² not being completely correct. It’s actually E²=m²c⁴ + p²c². The p²c² is not adding much, but it is still there.
I know that it is not a simple scale thing here. So it might be something else. My bet is that is has something to do with angular momentum,
And how does this fit the data?
I’m no astrophysicist - I just design computer chips. But this issue of “We need dark matter” came up with rotating galaxies, didn’t it? So I’d look into that direction if there is a potential connection. Classic bug hunting technique.
The Bullet Cluster, among several other systems, are very strong evidence that dark matter is actual baryonic matter that does not experience significant (or any) electromagnetic interactions. What we see when we look at these kinds of systems is that there is all evidence of STUFF there, but we cannot see the stuff. It’s not an indication of a poorly-performing math model missing a function term.
It would be like if we saw ripples in the water like we know exist around a rock. But we don’t see a rock. Sure, MAYBE we just fundamentally need to rewrite our basic rules of fluid mechanics to be able to create these exact ripples. But the more probable explanation is that there’s a rock we can’t see, and falsifying that theory will require just HEAPS of evidence.
The evidence we have suggests overwhelmingly that there is actual stuff that has mass that we simply do not have the tools to observe. Which isn’t all that surprising given that we are only JUST starting to build instruments to observe cosmological phenomena using stuff other than photons of light.
How would you know the difference? All the evidence of “STUFF” being there is obviously gravity based, as no other factors are involved. So that “STUFF” has a number of parameters that can be determined from the postulation of it’s existence: It should be baryonic to have the mass, and it should be stable, or one would probably observe energetic events related to state changes. Another point is: if it has mass, why does it not just clump together? I guess one can also rule out that it is charged, or one might see electromagnetic interactions. Did I miss a key parameter? Did I misunderstand anything here?
So do you know of any 3 (or maybe even 5 or 7) quarks baryon that would fit the pattern? The amount of combinations is limited, and CERN and others have created so many different particles over time that something of that kind that is actually stable should have made an appearance? Or are there any theoretical works on what kind of particle this could be, matching the pattern?
And, by the way, I would not call it a “poor performing” math model, as it covers quite a lot of the world we can observe. I deliberately used the term “incomplete”.
So have you actually looked into the data at all?
Sounds like the retired engineer that has a theory cliché.
Yeh, that’s how the scientific method works.
Observations don’t support a model, or a model doesn’t support observations.
Think of a reason why.
Test that hypothesis.
Repeat until you think it’s correct. Hopefully other people agree with you.
People are also working on modifying General Relativity and Newtonian Dynamics to try and fix the model, while other people are working on observing dark matter directly (instead of it’s effects) to further prove the existing models.
https://youtu.be/3o8kaCUm2V8
We are in the “testing hypothesis” stage. And have been for 50ish years
“Repeat until you think it’s correct. Hopefully other people agree with you.”
Dark Energy has entered the chat.
For those with time to spare: study all you can about neutron stars (including magnetars and quark stars), then go back to “black holes” (especially their event horizons and beyond) and there’s a good chance you’ll feel like a lot of aspects in BH theories are mythologies written in math - all of it entertaining, nonetheless.
For those who seek extra credit, study zero-point energy before reflecting on cosmic voids, galaxy filaments, galaxies, gravitationally bound celestial systems, quantum chromodynamics and neutrinos. Then, ponder the relativity between neutron stars, zero-point energy and hadron quark sea.
The attempts to measure dark matter directly have gotten incredibly sensitive and still haven’t found anything.
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Multiple experiments to detect dark matter directly here on earth have been constructed. They expected a handful of detections a year given the estimates of local dark matter densities. Those experiments have not yielded any detections. This sets very restrictive limits on candidates for particle like dark matter.
I’m fully aware of astronomical observations that suggest the need for dark matter. That’s not what I was referring to.
So far, astronomical observations are all we have, the lack of terrestrial observations have only been able to elliminate candidate particles, not measure them.
Yeah, it’s legitimate science being done, but some people treat it as sacred and would fight you to no end because they say Dark Matter is some certainty, rather than approaching it with the proper scientific skepticism or with a statistical outlook.
For the most part believers in Dark Matter are cool, but a vocal minority practically worship it as the only possible truth.
The certainty is that there is something there, we just don’t know what it is. The name “dark” anything is irrelevant.
If a new hypothetical model showed that either some far off unobserved mass(es) or the currently observable mass can have the gravitational effects that were previously explained by dark matter, or any other far off idea about the nature of gravity at large scale: then there would be evidence there is nothing there. Currently there is no evidence that something is there, just that there are forces and motions that are not understood.
“just that there are forces and motions that are not understood.” - aka, there’s “something” there… Doesn’t have to be a physical something. You’re intentionally misunderstanding or misinterpreting just to try and win points on the Internet.
I mean, they are working on adjusting Newtonian dynamics for the situations where gravity between objects is low. This would fix the model for the strange galaxy spin and where 2 stars orbit eachother.
The issue with this is there are too many unknowns as we have a (relatively) fixed point of perspective. But statistical analysis is working on reducing the impact of those unknowns, and there is likely a paper published in the next few months regarding this.
Then, I guess it’s a matter of understanding why this applies. And maybe it applies because of dark matter, and it all wraps back round to an undiscovered thing.
Or, perhaps Newtonian dynamics isn’t complete but has been accurate enough to withstand all our testing (like taking 9.8 as the value of G on earth, even though it varies across the globe, and the moon/sun/planets also have a miniscule impact. For everything we do on earth, 9.8 is accurate enough)
Dark matter still has strong scientific support, although still undiscovered.
Modifying Newtonian dynamics has so far been disproven.
Both are worthy of pursuing
Okay I see what you mean, the meaning of your words missed me the first time, sorry. You’re saying something is happening, not necessarily that something else exists to cause it.
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Modified gravity theories are a well explored alternative to dark matter, but they aren’t popular for the simple reason that dark matter fits the observational data far, far better. Because currently there is evidence that something is there, extensive evidence.
All of physics is a “math model”. One we attempt to falsify. And when a scientist does prove some part of the model wrong, the community leaps up in celebration and gets to working on the fix or the next.
Dark matter started as exactly a catchall designed to make the model work properly. We started with a very good model, but when observing extreme phenomenon (in this case the orbits of stars of entire galaxies), the model didn’t fit. So either there was something we couldn’t see to explain the difference (“dark” matter), or else the model was wrong and needed modification.
There’s also multiple competing theories for what that dark matter is, exactly. Everything from countless tiny primordial black holes to bizarre, lightyear-sized standing waves in a quantum field. But the best-fitting theories that make the most sense and contradict the fewest observations & models seem to prefer there be some kind of actual particle that interacts just fine with gravity, but very poorly or not at all with electromagnetism. And since we rely on electromagnetism for nearly all of our particle physics experiments that makes whatever this particle is VERY elusive.
Worth observing that once, a huge amount of energy produced by stars was an example of a dark energy. Until we figured out how to detect neutrinos. Then it wasn’t dark anymore.
In short, you’re exactly right. It’s a catch-all to make the math model work properly. And that’s not actually a problem.
My personal dark matter theory is that 80% of all stars are surrounded by Dyson Spheres.
Well that’s a fun hypothesis that should be falsifiable. Why not write a paper with some maths predictions? That is a pretty extraordinary claim, but definitely fascinating.
I just read up on it a bit, and there’s multiple things disproving my theory:
Respect looking into it further. If you’re into to this sort of stuff, you might like YouTube channel Isaac Arthur.
I wish more people were like you on the internet
I know, I was so hype a few years ago when a new gravity well model supposedly eliminated the need for Dark Matter, but recently it’s been in the news as a scandal that also doesn’t fix everything.
Modified Newtonian Dynamics (MOND). It’s been the dissenting voice in the modern Great Debate about dark matter.
On one side are the dark matter scientists who think there’s a vast category of phenomenon out there FAR beyond our current science. That the universe is far larger and more complex than we currently know, and so we must dedicate ourselves to exploring the unexplored. The other side, the
On the other you have the MOND scientists, who hope they can prevent that horizon from flying away from them by tweaking the math on some physical laws. It basically adds a term to our old physics equations to explain why low acceleration systems experience significantly different forces than the high-acceleration systems with which we are more familiar – though their explanations for WHY the math ought be tweaked I always found totally unsatisfactory – to make the current, easy-to-grock laws fit the observations.
With the big problem being that it doesn’t work. It explains some galactic motion, but not all. It sometimes fits wide binary star systems kind of OK, but more often doesn’t. It completely fails to explain the lensing and motion of huge galactic clusters. At this point, MOND has basically been falsified. Repeatedly, predictions it made have failed.
Dark matter theories – that is, the theories that say there are who new categories of stuff out there we don’t understand at all – still are the best explanation. That means we’re closer to the starting line of understanding the cosmos instead of the finish line many wanted us to be nearing. But I think there’s a razor in there somewhere, about trusting the scientist who understands the limits of our knowledge over the one who seems confident we nearly know everything.
There’s no scandal. Some people who are leading proponents of MOND theory recently published a new paper using what might be the best scenario we currently have to detect MOND (wide binary stars), and their more precise calculations…are not consistent with MOND. They published evidence against the very theory they were betting on.
https://youtu.be/HlNSvrYygRc?si=otqhH6VINIsCMfiS
The best kind of researchers, I bet that really took a lot of courage to do since it’s so far from human nature.
You would like this https://www.youtube.com/watch?v=PbmJkMhmrVI
I am curious if the opposite of dark matter could be true; while dark matter inside galaxies would explain galactical motion, couldn’t the same be explained by something repulsive BETWEEN galaxies? If the latter were the case, it would also explain dark energy.
The observations of systems like the Bullet Cluster imply that dark matter is actual material – baryonic matter. Stuff that exists in specific locations and has mass. Modifying the math of the physical laws does not explain these observations without absolutely going into contortions where dark matter explains them quite elegantly.
I mean that is pretty much correct. We don’t know what it is, but we can see it’s effect
Even more so Dark Energy
Great example, and this brings up a great point about this topic - there’s a difference between what’s a scientific pursuit vs. what is current established scientific understanding.
Dark matter is a topic being studied to try to find evidence of it existing, but as of now there’s is zero physical evidence that it actually exists.
Its observed gravitational effects is evidence. Otherwise nobody would have given it a name.
Proof of gravity from an unknown source affecting an object isn’t indicative of that source’s characteristics, though.
We don’t even know if the force involved is gravity. In fact we don’t even know if a force is involved at all.
I mean yeah that’s why it’s called dark matter. Because we know nothing about it except that it has gravity and doesn’t interact much (if at all) with electromagnetic waves.
The problem is Dark Matter is a theory that proposes specifically currently unobserved matter exists to solve our math problem. That’s not something we can automatically assume, imo. It’s looking highly probable, but not certain. It’s not just a blanket term for impossible to understand forces, okay, it’s not a pseudonym for C’Thulu, it’s a very specific solution among many.
Nobody “automatically assumes” anything. Dark matter is the best candidate of possible explanations because it explains observation and still fits the standard model. Even if they find the necessary particles eventually, nobody would call it certain though. Certainty is a unicorn.
People in this thread literally are calling it a certainty. I’ve basically said the exact same thing as you and gotten downvoted to heck for it.
Well, not really. Your first reply to me got downvoted because you setup a strawman - arguing against something that wasn’t even the point.
Your second, the one you claimed said the same as mine, insinuated Dark Matter is just some mathy explanation among many. This doesn’t give it credit. It’s the current no 1 explanation with lots of evidence. Still didn’t get downvoted though.
There’s extensive evidence of it’s existence. We just don’t know much about its nature.
I’m with you here, I don’t understand dark matter and dark energy and the expansion of the universe. We see shit moving all the time in the universe. I’m still not convinced we just don’t understand the motion of the universe outside our envelope of observation and it’s explainable with conventional matter and energy. Im trying to learn a lot tho. I’m gonna watch that video someone posted to you.
Interesting tidbit for you. You’d think if it was a math model not working properly that could be explained away with adjustments to the model that we’d be wrong looking at all galaxies. And yet there are galaxies out there that appear to be missing dark matter!
https://science.nasa.gov/missions/hubble/mystery-of-galaxys-missing-dark-matter-deepens
https://www.space.com/galaxy-no-dark-matter-cosmic-puzzle
It doesn’t solve the problem but, it adds to the intrigue I think.