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OddClass134 t1_ja7p1zb wrote

Dark matter isn't actually "proven". The name really means more "stuff we don't know what it is yet". As such, you can't really model it, because we don't know what it is.

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praetorion999 t1_ja859zd wrote

Haven't the effects of it been observed like through gravitational lensing or is it still possible that a different theory of gravity is correct and explains it without dark matter?

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mkorman11 t1_ja8x7iv wrote

The effects of dark matter have been observed through a variety of effects across a vast array of scales, from galaxies, to galaxy clusters, to the cosmic microwave background.

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OddClass134 t1_ja8hbtw wrote

I'm not an expert, but I did attend a talk with an expert last week. It seemed his* theory is sort of neither, but rather that general relativity models just aren't being applied correctly. So underlying theory is the same, dark matter doesn't exist, but the math isn't mathing.

Edit for clarity

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praetorion999 t1_ja8kv0d wrote

Wait they actually said dark matter doesn't exist? We already know general relativity is wrong/incomplete because it isn't quantum compatible

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OddClass134 t1_ja8lq8e wrote

I mean doesn't exist in the sense of it not being-- as is commonly implied-- a "thing" that is invisible to us. It does exist in the sense of being the name of an observed inconsistency with our models, but the theory he presented was that it is a failure of the models to accurately model what we already know about, rather than it being that there is something out there (invisible mass, undiscovered particles etc) we don't know what it is.

Just one guy though. I'm sure opinions differ.

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ForTech45 t1_ja8tj6a wrote

I think you misheard what that guy said, because the leading theory is still 100% an unknown subatomic particle, and I would hazard to guess that 90-95% of physicists in a field involving dark matter believe that it is just that— matter that only interacts with gravity, or interacts extremely weakly with the other known interactions.

Most of the debates around dark matter are around the question of “what TYPE” of matter is it and there is really only one fleshed out alternative theory— MOND and it’s various offshoots— and it’s clunky and overly complex due to initial failures, and it still fails fully resolve the initial issues that led to the need for dark matter.

A universe filled with a cold subatomic particles that ONLY interact with gravity (not even itself) not only fixes most of the problems that required dark matter in the first place, but people are using it in other areas (universal structural evolution and such) and it works there, too.

Until dark matter is experimentally observed, it is still an open area of research…. But given decades of failures of alternative theories and cutting edge research discounting other theories, it’s getting harder to treat the cold WIMP theory as anything but accepted.

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OddClass134 t1_ja9iixt wrote

>I think you misheard what that guy said, because the leading theory is still 100% an unknown subatomic particle, and I would hazard to guess that 90-95% of physicists in a field involving dark matter believe that it is just that— matter that only interacts with gravity, or interacts extremely weakly with the other known interactions.

Ah, well yes then, I suppose that is the leading theory. That was not however the theory he presented.

He did not speak directly to or for its existence, but he did speak about how many of the effects attributed to dark matter may well be explained through re-examination of the theory of general relativity itself.

He began the talk with a criticism of a lot of high energy physics and particle physics. The association may have been one I made on my own, but the implication seemed to be that this theory was an alternative to the subatomic particle theory.

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ForTech45 t1_jaa67si wrote

What did he call the theory? What was the speakers name?

There are many alternatives, but very few are fleshed out and most are just frameworks

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OddClass134 t1_jaabdhx wrote

I dont hope to put anyone on blast, as it wasnt my presentation or my paper and I may be wrong.

I also think Im not being clear here when I say "theory" and considering the topic, I probably shouldnt throw that term around. I meant more the argument of looking at modifications of GR rather than for undiscovered particles. Which modification one supports is a different discussion.

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ForTech45 t1_ja8toyf wrote

It hasn’t been “proven” because it hasn’t been experimentally observed.

But most models treat it just as a subatomic particle that only interacts with gravity

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Cryptizard t1_ja7pvyw wrote

I think what you are looking for is the concept of a dark matter halo. It is the current best understanding of how dark matter is distributed around galaxies. If you use google you can find some diagrams of what it would look like if we could see it.

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Kind-Truck3753 t1_ja7k0rb wrote

How are you planning to make a physical model of something we can’t see…?

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Poise-on OP t1_ja7k4bg wrote

Based on the theories, im not trying to make it super accurate or anything, i just want to loosely represent it visually in a way i can explain to other people

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OmegaMordred t1_ja7mtpl wrote

You are joking right?

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Poise-on OP t1_ja7nbnp wrote

No😭 English isn’t my first language, and im a high schooler with no science degree or profound science knowledge, im not sure why my question sounds so stupid, please let me know so I can clarify (although im pretty sure now that my question is stupid inherently🥲)

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bostwickenator t1_ja7qb4j wrote

You question isn't stupid but the other person is stuck on the fact it's invisible so you can't see it. Now I think that isn't a problem because you can make an analogy which you can see.

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soundsthatwormsmake t1_ja7rtut wrote

So far dark matter and dark energy are 100% invisible. They are called dark because they are unseen. They are hypothetical. Dark matter is inferred to exist because there is not enough normal matter to explain the gravity effecting some galaxies. Dark energy is inferred because the expansion of the entire universe is accelerating much faster than can otherwise be explained.

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Poise-on OP t1_ja7s9oh wrote

Yes, and i wondered if i could represent the functions of it, i know i cant make an invisible model, thank you for this specific info tho! i appreciate it

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kassell t1_ja7yn83 wrote

BBC Horizon has made some documentaries in which they try to represent dark matter and dark energy. It looks nice and they even show some shots of how they made those sequences. Sorry I'm too busy to look those docs up for you now.

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ChrisARippel t1_ja8dq25 wrote

Have you considered making a the Cosmic Web?

Though many people have heard of Dark Matter and Dark Energy, I suspect fewer people have heard of the Cosmic Web. The idea will be new.

  • Matter and dark matter condensing into filaments. Where filaments cross galaxies appear.

  • Dark energy expanding voids between the filaments.

  • The Cosmic Web is impressively BIG.

10 year old video

Building the Cosmic Web on a computer. Part 1

Millennium Cosmic Web Simulation Project

There are more cool videos of Cosmic Web, e.g., tours through the web, etc. for a presentation.

Articles

Clues about Cosmic Web

Spinning Cosmic Web

Possible photograph of Cosmic Web

Cosmic Web could be hiding new physics

I think you could also imitate a Cosmic Web with cotton fibers, glue and paint.

Good luck.

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solidcordon t1_ja7ptxo wrote

Probably best to start with what you think these terms describe in terms of observed phenomena.

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bostwickenator t1_ja7qg2c wrote

Which of the properties of dark matter are you wanting to try and represent? Similarly with dark energy what do you want to show people?

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Poise-on OP t1_ja7sgmk wrote

I want to represent how they affect baryonic matter, like showing how baryonic matter behaves without the concept of dark matter vs how it behaves when dark matter is applies

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Hot_Egg5840 t1_ja7uuvj wrote

Just an artistic take on this, how about a scene depicting God at the drafting table crinkling up and ripping a design with a bunch of other wadded up designs on the floor.

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indrada90 t1_ja82qgk wrote

I think the problem you're gonna run into is that we really don't know. There are certainly reasonable models available, but there is lots of disagreement, and most of them will just look like a fuzzy black ball with a galaxy inside

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space-ModTeam t1_ja8uosr wrote

Hello u/Poise-on, your submission "How to make a model of dark matter and energy?" has been removed from r/space because:

  • Such questions should be asked in the "All space questions" thread stickied at the top of the sub.

Please read the rules in the sidebar and check r/space for duplicate submissions before posting. If you have any questions about this removal please message the r/space moderators. Thank you.

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