Could dark matter be just black holes?

[alpal]

This is interesting - about Black Holes - could they account for all the Dark Matter?

https://www.forbes.com/sites/startswithabang/2020/07/07/could-black-holes-be-the-dark-matter-our-universe-needs/?sh=5604ab5829bb


Could Black Holes Be The Dark Matter Our Universe Needs?


Ethan Siegel - Senior Contributor

Jul 7, 2020,02:00am EDT

So what about the idea of black holes? After all, black holes:
are dark,
don't emit light,
can have an enormous amount of gravitation, and
definitely exist, unlike (at least most of) the particle candidates we've concocted for dark matter.
The idea that black holes could play a role in solving the dark matter puzzle is an old one, going back many decades.


The idea that our Universe's dark matter might be black holes is interesting and deserves scrutiny, and get revived periodically as new generations of scientists take an interest in the old idea for themselves. But the data simply doesn't support it. Black holes as dark matter are both highly constrained and disfavored for numerous reasons, both theoretical and observational. Until new evidence supporting them comes in, don't believe the hype surrounding them, no matter how fashionable it becomes.

[AstroViking]

My theory is that this "dark matter" is merely compressed cynicism, and it's found in every workplace where Sys-admins and IT security people are employed.

[alpal]

I was hoping for some serious responses. :)

[xelasnave]

The proposition seems to be totally unsupported speculation and I am serious.
Why not say black holes are responsible for baldness if we are making stuff up?

OK I feel I am entitled to one guess...dark matter does not exist and comes from an unsupported reliance on sums that ignore the observations in favour of the sums and overlooking the reasonable conclusion that gravity must be derived from the pressure of everything manifesting as a external force as opposed to an unestablished attractive force and as an external force explains the unexpected galaxy rotational curves...
Perhaps if we made the sums fit the observations rather than the other way around we could avoid wasting time in un necessary speculation.

Alex

[alpal]

If you do a Google search you'll see a mountain
of evidence that dark matter exists.

Some scientists have tried to explain it with the MOND theory:
https://physics.aps.org/articles/v14/143

The MOND theory was devised more than 30 years ago as a way to explain galactic rotation data
without invoking the existence of the mysterious dark matter.

[xelasnave]

Why would you assume I make my statement from an uninformed position?

Just because we do not have the answer that is no reason to believe the current understanding of gravity has delivered to us the correct picture...why is that so difficult to understand. Gravity is the force that rules everything and yet we do not know how it works but armed with that flaw in our understanding fools feel free to speculate.

Here's a novel idea...we make an observation that tells us that to make our sums work we need a truck load of matter that we can not detect, other than by our sums,...why not conclude our sums are not reliable when applied at this level...again ask how do we know dark matter is there.the sums ..what observation , other than our sums, do we have?

Hmmm just because we can not answer that does not mean our current sums are telling us the truth...and always factor in....we do not know what it is that we do not know...

Alex

[alpal]

You seemed to be invoking the MOND theory without stating its name.

[xelasnave]

Well I thank you for trying to assist that is most kind.

I believe that Le Sage was on the right track however as is the way new ideas will try to discredit all that goes before them unless they use the frame work for the new idea and sadly his notion has become a taboo approach..

However it is so logical I fail to see why it is not given any credibility nor why the existence of a determination to avoid accepting there must be an aether and all that comes from that acceptance... now tell me just one experiment that has shown there is no eather.

Alex

[alpal]

The Aether is another topic -
here is an interesting scientific paper that proves it exists:


https://www.researchgate.net/publication/26842358_Combining_NASAJPL_One-Way_Optical-Fiber_Light-Speed_Data_with_Spacecraft_Earth-Flyby_Doppler-Shift_Data_to_Characterise_3-Space_Flow

[xelasnave]

Thanks for that excellent stuff.
Alex

[Addos]

Suggest you check out Dr Paul Sutter's recent podcast on the evidence for our current understanding of dark matter, and how popular alternate theories such as MOND and Teves dont hold up at certain observational scales.


https://www.youtube.com/watch?v=qm0dYbs5Dkc

[xelasnave]

Thanks for posting that for me...however I am not unaware of the current thinking the fact I don't agree should not be taken as evidence that I don't know what is out there...try me. ;)

The claim is dark matter exists I maintain that has not yet been established.

Just because dark matter has not yet been overthrown that does not mean that the prospect of it being discarded at some future time is impossible.

GR comes from applying the principle of equivalence and thereby using the formula for acceleration ...the very nature of equivalence means you are using something other than the matter under investigation rather than the subject of the matter under investigation..it would seem to me that there could be opportunity not to get it right at a universal level...

That is why I say that until we can determine how gravity works ( quantum explanation) we should be careful believing that an invisable matter exists when the only evidence for same is the equations that says that it is there...

If gravity is seen as an external force then the rotation curves are to be expected...give it some thought before you casually dismiss the notion.

Now of course I am a layman and hence the dogged desire to understand how something works and not entirely rely on equations derived by applying the principle of equivalence.

Clearly they work and yet in the case of dark matter they do not fit the observations...perhaps room should be left to consider that in this area the equations are unable to describe the observations rather than shoe horning the observations to fit the equarptions..is that unreasonable?

The dangers of such an approach are obviously not realised by those who believe the equations are the definitive explanation of gravity.

The thing that works very much against progress is the belief that GR puts the matter to rest and rather than fund research to find a way forward GR attracts, in my view, so much funding that does no more than assure everyone in the business that they are right..look into the funding as it will take your breath away.....you will not move forward while we fail to point out the obvious..tell me what in GR has not been tested?...the observations re galaxy curves point more to a failure of the equations at the galactic scale than there being some otherwise undetectable matter.

Fortunately I know how gravity works:P and that is all that I care about but it saddens me that the world can not work out how gravity works as that would be the most important knowledge humans could gain.

However if anyone wishes to discuss gravity I am more than happy to do so as it has been my passion for perhaps more than thirty years but I am a mug after all and as such happy to be shown what I do not yet know.

And I assure you I will not make any rat bag claims or try to discredit what we already know ...I do not think one has to tear down what went before to establish a new idea...

I am only a layman so disussion can only be at that level but I an happy to venture deeper;)..

Alex

[Stonius]

I agree, Alex, if your model predicts something like dark matter, then you look for experimental evidence supporting that prediction and fail, the model should be falsified, pending new evidence.

At this point I think there is something wrong with our fundamental understanding of gravity, rather than an undetectable darkmatter.

[xelasnave]

Thank you for your post Markus.

The biggest critism of the fundamental " push gravity" approach which translates into gravity being a universal pressure is that " they" can't find the "particles" yet ironically there have been many mines housing cleaning fluid to catch dark matter...not sure if they have found many yet.

I wish I had the inclination and the ability to write a computer program to replicate what must occur in reality which is that at any point..any point..there is a little piece of the universe passing thru that point at C presumably ( make a list)..and for every point in the universe...an easy way to contemplate the reality that I "see" is to imagine a single point and make it the centre of a ten billion light year sphere.larger or smaller will make little difference..now imagine how many trajectories thru that point..near infinite would be a reasonably good guess from a geometric point of view...however then think how many "particles" or energies travel along each trajectory and then ask would this not create the gravity pressure I suspect? But in such a program I feel that one could place a galaxy and observe the rotation curves... I can imagine it and I just know that program would demonstrate that dark matter is not real.

I like putting lens in this environment (You can draw this in two dimentions to get the point) and asking which way the light will bend on the basis the "fat" part of the glass shields to produce a slight imbalance on either side of this pressure and where the light will then need to travel the lens restricting the flow more on one side than the other.

If you are able to do both the things I suggest you can get an insite into how it all works...

The main thing is to think about how it must work and finally that reduces to the system I suggest...but hey I am only a mug so it is just speculation..I never invest so heavily in an idea that I will insist that I can only be right..but what makes me think I am on the right track is we take for granted a force we call attraction exists but when you think about it there is no way each object can have such a relationship with everything else...the pressure idea is simple and avoids unestablished forces such as attraction.

I hope you and yours are all doing well.

Alex