B Unraveling the Mysteries of Dark Gravity

[Rotating Wave]

TL;DR Summary

Though I am a beginner, I do have a severely (I think) advanced question concerning Dark... Substances.

There are anti-protons and anti-electrons (anti-neutrons, too?), and "Dark Matter" and "Dark Energy" and, presumably, a "mirror version" of everything in our universe. I don't know a GREAT deal on this subject and I wondered: Is there a "Dark Gravity" that is throwing off our calculations with gravity? Or does it have to be something missing from Einstein's equation (like his was filling in something missing from Newton's equations?

 

[Ibix]

Antimatter, dark matter and dark energy are three different things. All particles we're familiar with have an antiparticle, yes, although at least in the case of the photon it's its own antiparticle. Antimatter is a well understood phenomenon.

Dark matter and dark energy are simply proposals that cover mismatches between our theories and reality. Dark matter provides invisible extra mass to make galaxies massive enough not to fly apart under their observed rotation, and also explains some structure in the cosmic microwave background. Dark energy provides a slight tweak to the expansion rate of the universe that you cannot provide by messing around with matter and radiation density.

Dark gravity appears to be a term you've invented yourself. However there are modified gravity theories that attempt to explain the phenomena normally explained by dark matter and dark energy. There are various modifications to Newton's theory of gravity (modified Newtonian dynamics, MOND) that do explain galaxy rotation curves rather well. However, they don't explain the CMB structure that dark matter does, and attempts to make similar modifications to general relativity have always failed.

So alternative gravity theories versus dark matter and dark energy is still an open question. The weight of opinion seems to side with dark matter and dark energy at the moment, but time will tell.

 

[weirdoguy]

Dark gravity appears to be a term you've invented yourself.

He invented another meaning of this term, but the term appears in google search and arxiv: https://arxiv.org/abs/0711.0077

 

[Rotating Wave]

Yeah, I made the term up, but only to try to explain a concept. I didn't know it was already a term being used (guess I should have googled it first). And, I knew that anti-particles were different from Dark Substances, but I did not realize dark substances were not part of the same thing.

But COULD they be part of the same thing and we just aren't putting them in the same category? Well, I guess they could be, since it appears we basically just made them up to account for unexplained phenomena (or, perhaps, found the unexplained phenomena and labeled it thinking we did not yet have the explanation?) in our normal calculations.

People laugh at me a lot because I conceive new things based on my limited knowledge. I don't act on it as though it's true, but... hypothesize about it and present it for evaluation.
I ask this one because I wondered if perhaps space has its own gravity - perhaps too small to notice usually, but on a massive scale it becomes more noticeable. And on a minute scale isn't even worth mentioning, and that is why the different scales of size have different apparent mass/energy/gravity behaviors.

But, like I said, I'm just presenting an idea for understanding. I'm sure it's probably not a valid hypothesis, but unless you present it for fact-checking, or figure out how to make the equipment and test it yourself, you can't be positive it's invalid. To me anyway.

You both have already provided me with a great deal more information than I already had, and I truly appreciate it. And, I apologize for my ridiculous questions. Like I said, I can't know they're ridiculous until I've researched to discover that, you know? Thank you again, Ibix and weirdoguy, for the input. I appreciate it.

 

[Ibix]

But COULD they be part of the same thing and we just aren't putting them in the same category?

Dark matter is a form of matter that just doesn't interact electromagnetically (perhaps apparently a minor difference that turns out to have Implications). Dark energy is a negative pressure term in the Einstein field equations. Beyond the name, there's no real similarity between the phenomena (which is probably an argument against "cool" naming conventions in physics). They may turn out to have a common cause in a successor theory to general relativity if modified gravity is indeed the correct approach, but very unlikely if they are actually forms of matter and energy. Dark matter is not uniform throughout space; dark energy is.

hypothesize about it and present it for evaluation.

This is a common approach, but it's extraordinarily inefficient. The problem is that you need to understand our current theories well enough to manipulate them and our current observations well enough to understand what the differences from theory actually are before you can really understand the problems. And if you don't understand the problems your hypotheses are little more than blind guesses. This site therefore has a "no discussion of personal theories" rule.

If you want to learn about the science this site can help you a lot. I'm an amateur myself these days, and can personally attest that there's a lot of reliable stuff (lecture notes, textbooks, online lectures) out there to get you a solid foundation, and that there are a lot of skilled people here willing to help with that. But our experience is that unfounded speculation is a waste of everyone's time. It's a bit like discussing the game in the office on Monday morning - we'd rather spend the time playing the game ourselves, learning to play ourselves and teaching others.

 

[Rotating Wave]

Dark matter is a form of matter that just doesn't interact electromagnetically (perhaps apparently a minor difference that turns out to have Implications). Dark energy is a negative pressure term in the Einstein field equations. Beyond the name, there's no real similarity between the phenomena (which is probably an argument against "cool" naming conventions in physics). They may turn out to have a common cause in a successor theory to general relativity if modified gravity is indeed the correct approach, but very unlikely if they are actually forms of matter and energy. Dark matter is not uniform throughout space; dark energy is.

This is a common approach, but it's extraordinarily inefficient. The problem is that you need to understand our current theories well enough to manipulate them and our current observations well enough to understand what the differences from theory actually are before you can really understand the problems. And if you don't understand the problems your hypotheses are little more than blind guesses. This site therefore has a "no discussion of personal theories" rule.

If you want to learn about the science this site can help you a lot. I'm an amateur myself these days, and can personally attest that there's a lot of reliable stuff (lecture notes, textbooks, online lectures) out there to get you a solid foundation, and that there are a lot of skilled people here willing to help with that. But our experience is that unfounded speculation is a waste of everyone's time. It's a bit like discussing the game in the office on Monday morning - we'd rather spend the time playing the game ourselves, learning to play ourselves and teaching others.

Ok. I didn't realize about the rule. But, I wasn't actually just proposing my own theory, but trying to understand the principles it would require to be valid/invalid.

From the comments here, I learned that "dark" is not a type or subset, but more of a term meaning (if I'm interpreting correctly) "still dark in comprehension; unclear or mysterious." I had been under the false impression that they were related in a different way than just their mysterious nature.

I am still studying the basics - or, rather, refreshing on them - but also have a few conditions that keep me from moving forward. I'm ADHD/HFAS and I try REALLY hard to stay focused on one thing but it makes my brain jump to other things. Like here, I wasn't even on the thought of "dark" anything but electromagnetism and somehow my brain went from there to gravity (I think it was the similarity of their equations) and then... idk. Somehow that ended up at "dark gravity" and I kept trying to go back to electromagnetism but couldn't focus and kept coming back to this concept.

So I asked to get it out of the the way and let my focus get on track again, while hoping to also learn some things that, even if they don't stick right now, might make it easier to understand them later when I get to them in my study progression.

I don't mean to violate any rules with it and would like to know if anyone knows of any sites meant to discuss such hypothetical possibilities so I don't break the rules again?
Again, I didn't mean to, and I'm sorry for wasting people's time with it. I didn't realize that would be what I was doing and I feel bad about it. So, please, any references where I could do this without it being a waste of time, but also where it can be factually contested and not just discussed and amused over, would be very helpful.

 

[jbriggs444]

where I could do this without it being a waste of time

To be blunt, there is no such place. There are places where you can engage in speculation without wasting our time. You will certainly waste someone's.

Looks like sci.physics is still around. And after ten years away, the names still look familiar. Signal to noise ratio has to be microscopic by now: https://groups.google.com/g/sci.physics

Note that sci.physics pre-dates the Internet. It dates back to UUCP and usenet.

 

[etotheipi]

Looks like sci.physics is still around. And after ten years away, the names still look familiar. Signal to noise ratio has to be microscopic by now: https://groups.google.com/g/sci.physics

Goodness, I really wish I hadn't clicked that link . In the words of ol' Ben, "you will never find a more wretched hive of scum and villainy". Makes me very grateful that the mods do a fine job of maintaining order around here, and making sure that the occasional crackpot is booted into to the trash compactor

 

[jbriggs444]

Goodness, I really wish I hadn't clicked that link . In the words of ol' Ben, "you will never find a more wretched hive of scum and villainy". Makes me very grateful that the mods do a fine job of maintaining order around here, and making sure that the occasional crackpot is booted into to the trash compactor

Usenet is a worked example of what happens when you have unmoderated discussion groups. The original implementation model was essentially unmoderatable. Attempts to moderate with "retromoderation" (forged cancellations) and the "Usenet death penalty" proved inadequate to the task.

The existence of whimsical groups such as "alt.swedish.chef.bork.bork.bork" was a nice touch.

 

[PeroK]

In the words of ol' Ben, "you will never find a more wretched hive of scum and villainy".

Is that Ben Jonson?

 

[jbriggs444]

Is that Ben Jonson?

Star Wars, Obi Wan, "Old Ben".

 

[Rotating Wave]

To be blunt, there is no such place. There are places where you can engage in speculation without wasting our time. You will certainly waste someone's.

Looks like sci.physics is still around. And after ten years away, the names still look familiar. Signal to noise ratio has to be microscopic by now: https://groups.google.com/g/sci.physics

Note that sci.physics pre-dates the Internet. It dates back to UUCP and usenet.

I wouldn't call it a waste of time as long as information is exchanged. It's certainly going to save time for me because I can then return my focus to my studies quicker. In some senses it will hinder progress but, as long as it is meeting a goal, it does not waste time, in my perception.

However, I understand how it does here, as that is not the goal of this site, so... not meeting the goal === waste of time.

But thank you for the resource (and the fascinating background of it). I will use those such sites to discuss the "overflow," and reserve this specifically for my direct studies.
My apologies to everyone whose time I wasted, and my gratitude for sacrificing it to help me understand. Thank you.

 

[Rotating Wave]

Goodness, I really wish I hadn't clicked that link . In the words of ol' Ben, "you will never find a more wretched hive of scum and villainy". Makes me very grateful that the mods do a fine job of maintaining order around here, and making sure that the occasional crackpot is booted into to the trash compactor

I hadn't gotten to the link yet...
Is it really that bad? Like, on the level of flat-earthers?

 

[Rotating Wave]

Wow. I just looked at the link.
I really am sorry if that's how I come across. I promise I don't believe what I present to be true just because I presented it. I'm actually HOPING people will tell me it's nonsense so I don't focus on frivolous things and can study enough to not have to ask such questions but be able to figure out the answers through pre-tested and established methods (the knowledge of science and its method).

One more question:
How do you close a thread? I don't want people to waste their time on one if it shows to be a waste. Still pretty new to the site and still learning the navigation of it.

 

[phinds]

I wouldn't call it a waste of time as long as information is exchanged.

It's hard to see how you consider ruminations on hypothetical / non-existent "science" an exchange of information. Better you focus on REAL science.

 

[jbriggs444]

Wow. I just looked at the link.
I really am sorry if that's how I come across.

No worries. Those guys are hard-core crackpots. Completely immune to rational engagement. It is clear that you are not nearly that far gone.

How do you close a thread? I don't want people to waste their time on one if it shows to be a waste. Still pretty new to the site and still learning the navigation of it.

The standard practice is to leave threads out there "forever". If they end up attracting off-topic traffic (such as a discussion of Usenet, *cough*, *blush*), that content might be cleaned or the thread closed to further postings.

 

[mitchell porter]

I wondered if perhaps space has its own gravity

The "zero-point" energy of the quantum fields that fill space, should certainly be a source of gravity, actually so much gravity that the universe should look quite different; and how this is resolved in the real world is one of the unsolved mysteries.

It's an aspect of what's called the "cosmological constant problem". The zero-point energy of all the fields should add up to a vacuum energy that is a source of gravity. Maybe that's what dark energy is, but then why is it as small as it is? Well, maybe if it was any bigger, we wouldn't exist (anthropic principle), and so it was logically inevitable that we find ourselves in a possible world where negative and positive zero-point energies mostly cancel out. Or maybe there's some symmetry like supersymmetry that is the real reason for this cancellation. Or maybe there's some kind of graviton screening effect that traps the gravity of the vacuum energy, and dark energy is a quintessence field and not vacuum energy at all...

 

[Rotating Wave]

It's hard to see how you consider ruminations on hypothetical / non-existent "science" an exchange of information. Better you focus on REAL science.

As an example, here I posed a rumination. But, I learned about the differences between dark substances and found they are not related in any known way other than their naming. I also learned that a photon is its own antiparticle. Information was exchanged. I also learned that this "discussion" part of this site wasn't intended for general discussion in science but for discussion of pre-established principles in science.
So, just as I didn't see how it was not possible for my principle to be valid, yet it was still true, so also just because you don't see how it is not a waste of time doesn't make it so. If one fails to find anything of worth in a discussion, then it is a waste of time for them. But relativity applies here as well. Not everyone will fail to gain something from a conversation another has failed to gain from.

 

[Rotating Wave]

No worries. Those guys are hard-core crackpots. Completely immune to rational engagement. It is clear that you are not nearly that far gone.

The standard practice is to leave threads out there "forever". If they end up attracting off-topic traffic (such as a discussion of Usenet, *cough*, *blush*), that content might be cleaned or the thread closed to further postings.

Thank you for that. I was taking it to heart, thinking I was referred there for thinking like that. I appreciate this more than you probably understood I needed to hear this.

 

[Rotating Wave]

The "zero-point" energy of the quantum fields that fill space, should certainly be a source of gravity, actually so much gravity that the universe should look quite different; and how this is resolved in the real world is one of the unsolved mysteries.

It's an aspect of what's called the "cosmological constant problem". The zero-point energy of all the fields should add up to a vacuum energy that is a source of gravity. Maybe that's what dark energy is, but then why is it as small as it is? Well, maybe if it was any bigger, we wouldn't exist (anthropic principle), and so it was logically inevitable that we find ourselves in a possible world where negative and positive zero-point energies mostly cancel out. Or maybe there's some symmetry like supersymmetry that is the real reason for this cancellation. Or maybe there's some kind of graviton screening effect that traps the gravity of the vacuum energy, and dark energy is a quintessence field and not vacuum energy at all...

I understand that zero-point energy, gravitons, and such are hypothetical as well, but more plausibly valid than most (so, allowed to be thought of under the principle of Occam's razor). But it does make me feel better to know it's possible my brain isn't just throwing absolute garbage at me but things that are still plausible (granted, on the basis of other hypotheticals).

And now I also know which field to direct my studies later to continue investigating - if the question is still a question then. For now, my brain is satisfied knowing the information given here and is letting me focus again on other things. (I really don't like that it hijacks my thought like that and it's a relief to be able to focus on what I want to again).

Thank you everyone for helping me to understand. I didn't absorb ALL the information, but I got quite a bit and know what to go to further understand. And I apologize again for causing you to detour from your interests and foci. But, i promise I won't let it be a waste of anyone's time, even if they don't understand how their time was put to use.

Back to electromagnetism. !!