Black holes ruled out as universe’s missing dark matter
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Why did the Big Bang not just produce a Big Hole? IOW, if all the current mass of the universe was in a small volume wouldn’t it have promptly created a black hole?
I’m assuming the answer has something to do with mass not actually existing in its current form until the universe expanded enough. However I don’t have any mental framework to understand why that would be true. If someone reading this knows the answer and can point me at it, I’d be grateful. TIA!
Just stumbled upon this: https://www.reddit.com/r/askscience/comments/8p7hnn/where_an...
Another possibility is that black holes are places where lots of mass accumulates in the same place in space, while the big bang was a rapid expansion of space itself. Even if there was enough mass in one spot to be what we'd consider a black hole, the space it occupied expanded, dragged the mass along with it, and ripped the black hole apart.
It does. So do pressure and stresses. The full "source" of gravity in General Relativity is the stress-energy tensor, which includes all of these things.
If there was no mass then what made the energy slow down?
For example a photon will travel at the speed of light in a vacuum indefinitely.
In what scenario does energy just slow down without interacting with matter?
A single photon cannot have mass because it has zero energy in the reference frame where it is at rest (zero net momentum). But a pair of non-parallel photons can have rest-mass, and indeed the mass of the photons inside a star is considerable, for example.
Not if you're talking about what the source of gravity (spacetime curvature) is. Massless particles still have energy and still cause spacetime curvature.
Yes, but not in a context where radiation is present, since radiation can have energy but has no rest mass (rest energy).
I didn't catch this before, but it is not correct. There is no such thing as a frame in which a photon is at rest.
This is partly true. During inflation, the universe was vacuum; all of the energy was in the "false vacuum" state of whatever field caused inflation (it's usually called the "inflaton" field, which IMO is a very confusing name). When inflation ended, all of that energy got transferred to the Standard Model fields, forming matter and radiation at very high temperature and expanding very rapidly.
So the "all energy at first" part is true; but the "had to slow down to become mass" part is not. The matter and radiation was there as soon as inflation ended; it didn't have to slow down first.
Check out Alan Guth's inflationary universe - a surprisingly accessible book on a deeply complex subject.
Someone please correct me where I'm wrong!
I suppose it's even somewhat plausible that the answer to your question, in combinations with the other theories, are "all true", and that for various reasons or models the first N big bangs did result in immediate/fast collapse back to another big crunch/black hole, and that each subsequent crunch/black hole created another universe, until there was a universe that survived long enough to create several black holes, and so on and so on...
[1]https://en.wikipedia.org/wiki/Big_Bounce [2]http://evodevouniverse.com/wiki/Cosmological_natural_selecti... [3]https://www.amazon.com/Life-Cosmos-Lee-Smolin-ebook/dp/B004T... [4]http://evodevouniverse.com/wiki/Cosmological_natural_selecti...
And that's why you didn't get a giant black hole. There was a lot of mass at very high density, and gravity was pulling very hard at it - but it was pulling (almost exactly) equally hard in all directions.
A finite universe would be similar, just adding a dimension.
We have no clue what is beyond the explosion itself and, for intents and purposes, that expanse is infinite by current understanding. Does that expanse contain other explosions? Don't know, there hasn't really been an observed overlap so far.
You could imagine that the explosion is happening on an extra dimension and our three dimensional universe is the wave front of that explosion. Except that the math doesn't actually require the extra dimension to exist nor there is any evidence that it does.
edit: also the cited diameter is only for the visible universe. The universe is currently understood to be infinite.
[1] my understanding this applies only to points of the universe that are not otherwise gravitationally bound with each other.
What isn't infinite is the observable universe. But the observable universe is just the view we have, its boundaries are defined by the observer. In fact my observable universe is different from your observable universe, by an insignificant amount.
When physicists talk about the universe, it usually means the observable universe. Simply because for us, that's all we have.
Wikipedia for one says the following. There is no mention of infinity.
"The Universe is all of space and time[a] and their contents,[10] including planets, stars, galaxies, and all other forms of matter and energy. While the spatial size of the entire Universe is still unknown,[3] it is possible to measure the observable universe."
I don't know the details, but I was told that with these assumptions, proving that the Universe is infinite is only a matter of mathematics.
That would mean you can communicate faster than light by moving a large mass.
That mass was not outside its light cone in the past. (This is one of the main points given in favor of inflation models: that they solve the "horizon problem" because the inflationary expansion means that mass over a region much wider than our observable universe was within our past light cone at the end of inflation.)
It’s a meaningful difference, but still avoids the black hole problem.
PS: The math really does not say anything about t=0, after ~t=10^-30 to t=1 seconds you don’t get black holes.
If you are talking about actual light, it is not correct to say that it travels, say, one light-second in spacetime. The arc length along a light ray's path in spacetime is zero, because it's a null worldline. The same goes for the boundaries of light cones, which are what I think you are actually trying to get at: light cone boundaries are null surfaces, so arc length in spacetime along them is zero.
However, I don't think what you actually meant by "one light-second" was "distance in spacetime along the boundary of the past light cone". See below.
> Not light second as a unit of distance in 3d space at t=0.001 seconds which is a rather meaningless number at that point.
No, it isn't. It's a perfectly meaningful number: a distance in the surface of constant comoving time labeled by the coordinate t=0.001 seconds (or whatever time you want to pick). And if you are trying to describe "the size of the observable universe", this kind of distance is indeed what you need to specify.
Your error, however, is to assume that at t=0.001 seconds, the observable universe was 0.001 light-seconds in size. It wasn't. Such a conclusion would only be valid in flat spacetime, but the spacetime that describes the universe is not flat. It is actually non-trivial to come up with a correct expression for the size of the observable universe as a function of comoving time (and the actual expression is model-dependent--for example, it depends on how long your model says the inflation epoch lasted).
> The math really does not say anything about t=0
I agree. I wasn't saying that it did. The inflationary epoch is not modeled as starting at t=0.
> after ~t=10^-30 to t=1 seconds you don’t get black holes.
Where are you getting these numbers from?
BTW, expansion alone is not quite enough to answer why the early universe didn't collapse. You can have very rapid expansion, yet a closed universe which eventually comes to a standstill and then starts shrinking. A better answer is that the universe is very close to having critical density, i.e. just enough mass to expand forever at an asymptotically declining rate, absent new drivers of expansion (i.e. dark energy).
One thing our answers have in common is fine-tuning: the universe started out ridiculously homogeneous, and ridiculously close to the critical density. Inflation provides a way to explain both those properties, but (as critics are fond of pointing out) at the cost of fine-tuning the hypothetical microphysics needed to drive it.
First you need to understand that the Big Bang was not an explosion of matter into space, it was an explosion of matter and space (technically space-time). This might be hard to wrap your head around, it might be easier to think about space-time as non-infinite, say curving back on itself like the surface of a balloon (though as far as we can tell it is infinite).
Second, during the early Universe just after the Big Bang when the energy density of the Universe was incredibly high the density was nevertheless incredibly uniform. So, let's say you are inside a soup of matter and energy with a density as high or higher than the core of a star, but there is matter in every direction, what way is gravity pulling you? This is the other non-intuitive bit, gravity isn't pulling you in any direction. Pick a volume of matter in space around you and consider how its gravity affects you, for every single volume there is a corresponding volume on the opposite side of you that has exactly the same mass and is exactly as far away from you, cancelling out the gravity from the first chunk. And this is true for every single bit of volume around you, there's a 1:1 mapping of bits of stuff around you with other bits of stuff on the opposite side of you which exactly counterbalances the gravitational force from the first bit. The gravitational field is uniform, so nothing collapses, no black holes form, no stars or planets form either.
It's only after the Universe continues to expand and minute variations in local density are gradually amplified (over millions of years) into denser and denser clumps that it becomes possible to form galaxies and galaxy clusters/super-clusters (and thus black holes).
Now, we don't know for sure whether or not there were isolated little "super clumps" of extra density in the early Universe which allowed for the formation of black holes prior to the formation of galaxies (so-called primordial black holes). That's one theory for explaining the existence of supermassive and especially ultramassive black holes, but it's unconfirmed. However, now it seems as though we have enough evidence to show that primordial black holes can't be the explanation for the evidence for dark matter.
This is a type of statement I have read many, many times, but to me, it's the same as saying "wakalixes!". I've never read anything that gave me a hint of why and how there should be a difference between two objects receding from each other and "space itself" expanding.
When they move 1 meter apart from each other through space, they'd move 1 meter back again to meet up. But when space itself is expanding between them, they've moved 1 meter apart but now to get back together they have to move 2 meters.
This has some other subtler ramifications. It means that the space between the two objects can increase at faster than the speed of light (because you can't move through space faster than light, but space can expand faster than light). Also, with the Higg's field's nonzero rest value _energy can be created from nothing_ by creating space. Yes, this violates conservation of energy.
Say they are two objects in the universe A and B. New space is created between A and B faster than the speed of light. There is a USB drive carrying a dump of wikipedia on B.
Does this imply information is now moving faster than the speed of light?
By geometry, the shortest distance between two points is a straight line. If A and B are two stationary objects, with a straight line being shortest distance between them. Then space is basically a twisted thread like path between A and B, More thread is created every time instant 't' than light can travel through it?
And if some one figures out a way to walk from A to B in a straight line then they can walk faster than anything that can walk on the thread?
_ _
|_|---------------|_|
A B
_ -----\____ _
|_|--/ \-|_|
A B
Figure 1 is the fastest possible way of going from A to B
If more space is added, and yet A and B remain at fixed positions, the only way this model will work is the path(possible way to go from A to B) gets looped/twisted and turned. In this case A and B remain at fixed positions but new space gets created. Its also possible in this model that as more and more loops get created fast enough, even by travelling at 'c' one can never arrive at B.
If the space is not looped or twisted this how A and B will move apart at increasing time instances t1, t2, t3
t1:
_ _
|_|--|_|
A B
_ _
|_|---|_|
A B
_ _
|_|----|_|
A B
_ _
|_|-----|_|
A B
tn:
_
|_|----------------
A
If the objects were stationary, this is how it will look
t1:
_ _
|_|--------|_|
A B
_ _
|_|---/\---|_|
A B
_ _
|_|---/|\--|_|
A B
_ --- B
|_|---/ |---
A (many loops)..
If you would crumble up the sheet of paper to a small ball than that would be a different embedding of the two dimensional space in our three dimensional space but importantly the two dimensional space would remain unchanged. That is a two dimensional creature living on the sheet of paper could not tell the difference between living in a nicely flat sheet of paper and living in the crumbled up ball of paper.
And that is the same in your picture, space is the string between A and B and you can not tell the difference between it being embedded in a straight or curled up manner. Even more importantly a space does not require any embedding at all. It is a limitation of our brains that we can only imagine a two dimensional space as a sheet embedded in our three dimensional space. A and B can get further apart without being embedded in any space and moving away from each other in the embedding space or having new space curl up in between them.
So your mistake is to assume that our space must be embedded in another space in order to be able to expand. This might be the case but it is not necessary and we have no evidence for that. It also starts an infinite regress, why wouldn't the space our space is embedded in be embedded in yet another space? And then that one and the next one and so on.
If our space was indeed embedded in another space and curled up there, than your suggested faster trip from A to B would be the equivalent of a two dimensional creature leaving the crumbled up ball of paper into the third dimension, moving a bit through our three dimensional space, and then falling back into the paper at a point nearby in our three dimensional space but potentially far away from the starting point if you moved only inside the crumbled up sheet of paper. You would literally have to leave space-time and move through a space that is not our space-time.
This is in some sense very similar to wormholes but in that case you do not have to leave space-time and move freely through the embedding space but you can follow shortcuts inside space-time due to the topology of it. But again there is no need for any embedding space even if all the pictures of wormholes show space-time with the wormhole embedded in another space.
... except on the edges... but maybe there wasn't an edge and space is sphericalish? And if it was back then, why wouldn't it be now? Which brings the question: if you go far enough in one direction, do you come back where you started? Can we figure out whether that's the case?
No, because it was expanding too rapidly. The usual intuitions about how much mass in how small a volume it takes to make a black hole assume that the mass is stationary, or nearly so.
[edit] and it seems this is true and can be explained by the space-time matrix not being bound by light speed limits.
No. No particle of matter outruns a light ray at the same location and moving in the same direction. Or, to put it another way, all pieces of matter are moving within the light cones at their spacetime locations. "Moving within the light cones" is the correct General Relativity version of "nothing goes faster than light".
The coordinate speed of pieces of matter can be greater than c, but in a curved spacetime that, in itself, is not a problem.
> A second issue is in Time 0.0001 seconds the observable universe is only a 0.0001 light seconds radius which limits how much mass could form a black hole.
That is, if you imagine all that mass-energy springing into existence in a vast universe (but with every point much closer to each other than today), there was not enough time for all that energy to notice the gravity of the surrounding mass-energy density and collapse into a black hole. Add to that the expansion rate (inflation), and the extreme uniformity of the young universe (which means gravity would have been pulling every thing in all directions rather than "inward" towards a soon-to-be-black-hole-center), and a collapse was impossible.
You can't; this violates conservation laws. In other words, there is no solution of the equations of GR that describes mass-energy springing into existence in a universe that was empty up to that point.
At the end of inflation, matter and radiation in the form we know them today (the quantum fields described by the Standard Model of particle physics) got a huge amount of energy pumped into them; but that energy did not come from nowhere. It came from the inflaton field--the field that caused inflation up until that point--so that energy was already there and there had already been plenty of time for its gravitational effect to be "noticed".
Back in my undergrad physics days, I postulated that our "universe" could be a big black hole inside some "extraverse". I worked through classical gravitational calculations to determine, from an estimate of the mass density of the universe, what the Schwarzschild radius (aka event horizon radius) of that black hole would be, and it came out to between 5 and 40 billion light years or so (the density of the universe is hotly debated, see other discussion in this thread about dark matter), which is at least the right order of magnitude.
For any constant nonzero density form of matter, if you pack enough of it together in a sphere in a flat spacetime, its Schwarzchild radius will eventually exceed its radius. This is because the Schwarzchild radius is proportional to the mass, but the radius of the actual matter is proportional to the cube-root of the mass.
It's a fun thought experiment, but not physically meaningful in this universe because our spacetime is expanding, and the original calculations assume there's nothing at the edge pulling 'outward', but in our universe there is.
You can't do this in flat spacetime, because the matter curves spacetime, and the denser you pack it, the more it curves spacetime.
The point of the thought experiment was that you start with a universe with no other matter in it that's not expanding, both of which conditions our universe violates.
No one really knows anything about the universe before 10^-42 seconds, and there is no physics to describe what likely happened. Photons/light and matter as we known it didn’t exist and wouldn’t for another 400,000 years.
There are many very deep issues that are explained pretty well here https://youtu.be/JDmKLXVFJzk It’s pretty heady so be ready
From the perspective of light, what is the difference in the universe at the instant of the big bang and some time after it? Well... potentially nothing. The structure of the universe only makes sense from within the context of the universe itself. The space of the universe only makes sense inside the universe. The time of the universe only makes sense inside the universe.
It's not the case that the big bang exploded material into empty space. The amount of energy/mass in the universe has never changed from the perspective of the universe. The big bang is the distinction of structure in the universe. What is the difference between a point and an infinite space of uniformity? When an infinite space of uniformity loses absolute uniformity, what happens?
Why did the universe not collapse into a singularity? Because it was already a singularity. It would require some kind of structure in space in order for a "collapse" to make sense. As soon as the structure is created, it is no longer uniform, and so it will no longer collapse uniformly - especially if space is expanding at the same time. I suspect there are several black holes at the "centre" of the universe, but I can not think of a way for all the matter to collapse into a singularity.
There is Universe n-1 (before ours). Last matter and anti-matter collide. Then, as there is nothing and as there is everything, the cycle begins again since we can't achieve "the balance". A big bang occurs, a universe n is born, with it's own set of laws (the laws of physics, like a new buildconfig). Everything slowly spreads and gets into perfect balance. Then everything dies. Then the last bits of matter stop existing. The Boom. A new universe is born, n+1. It has it's own set of constants. Maybe they aren't balanced properly, so it lives for a short moment and then dies and n+2 is born. And so on and so on.
In that case the big bang is compatible with a universe that has always existed and did not have a beginning
If the world has begun with a single quantum,
the notions of space and time would altogether
fail to have any meaning at the beginning;
they would only begin to have a sensible meaning
when the original quantum had been divided into
a sufficient number of quanta. If this suggestion
is correct, the beginning of the world happened
a little before the beginning of space and time.
The expansion is an expected behaviour of space time, and is predicted by general relativity given a certain parametrization of the density of matter an energy of the universe. To explain the acceleration, though, a large energy parameter is required, which has not been yet identified with any known process, although many theories exhist; as placeholder the parameter is known as dark energy. It is of course possible, but generally considered unlikely, that general relativity is incomplete and another theory could explain the acceleration without dark energy.
And it's not that the lightspeed increases with time, either. Rather, so they say, space expands - which is imaged trivially by stretching the space axis. I suppose that's normalizing for time and you could just as well fix space and compress time, invariably, to arrive at your notion, with a total lack of rigour at that.
So normalizing for
It depends on what you mean by "the big bang". The strictly correct meaning of "the big bang" is "the hot, dense, rapidly expanding state of the universe that is the earliest state for which we have good evidence". We know that state occurred a finite time ago--about 13.7 billion years.
What we don't know for sure is what came before that state, or how far into the past whatever came before it extends. The current best theory we have is that it was some kind of inflationary epoch, but different models of inflation give different answers to the question of how far back in time that epoch extended. AFAIK the possibility that inflation extended infinitely far back in time (i.e., that there was never any "initial singularity") has not been ruled out.
The expansion is accelerating now, but from the big bang up until a few billion years ago, it wasn't; it was decelerating. So you can't just extrapolate the current acceleration back in time.
I’m not claiming dark matter doesn’t exist, only that I fear the human tendency to run with a hypothesis too eagerly and discard alternate options.
Similar to how everyone seems to speak as if Hawking radiation is a given fact, when it is thus far completely unproven and nothing more than a suggested idea.
With regard to the article, it could still be that there are many young smaller black holes, too small or even too short lived for the methods employed here.
The primary focus on matter as the candidate is that if you don't believe that some form of matter is responsible, you begin having to explain how a lot of our Laws are incorrect. Dark Matter is really a problem that we have a notion how our Laws should work at the cosmic scale, yet they don't. And yet, we don't see any obvious reason why they shouldn't give how thoroughly we've tests these Laws.
For instance, if you say that our equations for gravity is off, why is it completely consistent for everything in our solar system? Why is consistent down to the most precise test for gravitational frame pulling? It seems to be only different when you talk about very large masses creating gravity on objects tugged at very long distances. Why does it just cut over to different behavior?
If you say that gravity is emergent, then how do you explain the standard model's place for the graviton? Granted, it's not testable (gravity is so weak it's beyond direct testing), but it seems to be fit right in to a spin-2 tensor where we would expect a gravity-like particle to be. Why would you expect that to not be true?
That said, Dark Matter matter candidates are getting weeded out pretty quickly, these days. No new types of particles are being discovered, and Dark Matter observatories are largely coming up empty. But, that's science: got an idea? Test it and let the results speak.
As an aside, I think one thing to remember is: just because science doesn't know the answer to something, it often knows what can't be the right answer. Look into the theory's and their criticisms.
I'm completely ignorant of the subject so I don't know how crazy that might sound.
The Newton/Einstein definition is that it is an effect by mass on space/time. Mass always travels in a straight line (unless acted on), but mass causes space/time to curve. So, what we see as gravitation attraction is a fake force. No different than being "pushed" into the back of your seat when a car accelerates. You are staying still, the car is moving forwards. The Newton/Einstein definition does not specify any mechanism. The description, however, is highly specific, and so far every test for the most subtle effects have been validated. Well, except for cosmic structures.
Quantum mechanics says that particles emit/receive interactions via the graviton carrier, and that it can be quantized and transmitted via waves. In the last few years, we have detected gravitational waves. It fits perfectly and exactly as we would expect over cosmic distances. Unfortunately, the amount of energy necessary to detect an actual graviton is beyond anything we can expect to be able to produce for the forceable future and likely will never have the resources. So that is out. Also, it makes no claim on how it can affect space/time.
So, just like we original argued over whether or not it was particles or waves, I think this paradox strongly suggests that we're just not looking at gravity correctly. I suspect that the real problem is "What is time?" Why do things experience different rates of time? It seems obvious to me that gravity, time, and entanglement are related. Gravity is very likely to be Dark Matter: a stand-in name until we can grasp the fundamentals.
Sorry for the late reply. Why is that? What determines the amount of energy needed to detect a given particle?
We have observed specific phenomena but not that which created such phenomena.
As far as "Black Holes" as per theoretical descriptions are concerned, they cannot exist in a finite time universe as far as we (the observers) are concerned. The theoretical models used all have as a basic assumption that increasing gravity (whatever that may be) will cause a slow down in time as observed at distances away from such increase. As such, all phenomena involved in the creation of such entities will slow to a complete stop as far as we are concerned.
Hence, if the universe is of any finite duration, we will not have seen the creation of even 1 black hole of any kind. On the other hand, if the universe has existed eternally, it is still likely that these entities are still in the process of formation and not yet in existence.
I don't doubt we are seeing some interesting phenomena, but not the entities called "Black Holes". The argument for the creation involves changing perspective to some observer who is falling into or through the event horizon (choose which one of these you want, as there are apparently a couple of choices here in the theoretical models). Since we are not such observers, that perspective is actually irrelevant to us. What is relevant is what we observe in the universe at large.
The basic problems (irrespective of mathematical assumptions) with the processes of "Black Hole" generation relate to non-uniformity of compression, time dilation and other basic assumptions for the "Black Hole" models.
I find the reasoning used for the existence of "Black Holes" in our universe to be lacking in logical rigour and appears to have a lot of hand-waviness to it.
I am currently reading the documentation for the Metamath system and there are some quite enlightening comments in that about mathematics and those who study it. Especially as it relates to us who are not mathematicians as our career. One of these relates to the amount of "faith" we have to exhibit when trusting that specific "proofs" are in point of fact true. Even mathematicians who are not in that specific speciality do not have the necessary background to verify any proof outside of their own mathematical area.
Mathematics is a profoundly useful tool but as we have seen in the past and we will see in the future, it has problems (like all areas).
The evidence for the existence of black holes is incredibly strong at the moment. In fact in some ways it's stronger than the evidence for the existence of atoms about a century ago. Nobody except cranks or extreme contrarians seriously disputes the theory these days.
https://en.m.wikipedia.org/wiki/Magnetospheric_eternally_col...
I rather think we'd have noticed the difference from LIGO gravitational wave measurements of BH mergers, but maybe not?
--
We have made certain observations that are assumed to be the result of matter falling into a "Black Hole". We do not have any observations that show us this as a fact. Read the observational material very carefully.
Go back over the last few decades and see how many times it is declared "we have seen x for the first time", where x is the is the same entity each time, in this particlualr case "Black Holes".
Men (women, children) want to believe that they have a certain handle on the truth and reality. What is very unpleasant to most is not having that certainty. This applies to all people across the board and even more so to those whose expertise is dependent on their being right. Many scientists are in this category.
It is often difficult to sit in the place of recognising that we just don't know. We have some ideas which, on the evidence, give a handle to investigate further, but we should understand that our understanding can be turned on its head.
The evidence for the existence of something is there, yes. But, is it a "Black Hole" of the theory presented, hmmm, that is unknown and for the time being, unknowable. As we cannot get out there and actually do the appropriate experiments to test this. We can only do remote observations and these can be easily misinterpreted.
>>Nobody except cranks or extreme contrarians seriously disputes the theory these days.
The problem here with this view is that it has been "cranks" and "extreme contrarians" who have brought about the biggest changes in science. There are Nobel Prize winners amongst them. All views about the nature of our universe should have those who dispute it. This should spur on our investigations into the nature of the universe. If we are unable to handle someone disputing our models and theories of the universe, then what are we doing? We are not serious about expanding our knowledge, we are serious about our reputations and being right.
The biggest problem for science today is that people don't trust it because it keeps getting things wrong, yet all the while saying that it is the only source of truth.
Science is one of a group of tools we can and should use to investigate the universe around. It has its limitations as does all the other tools we have and we need to recognise that though this tool is helpful in understanding, it is not the tool that gives us the truth.
In your eyes, that evidence may be "beyond a reasonable doubt", but from my perspective, that evidence barely scratches the surface of what we need.
Science is not about dogma, it is about investigating the universe about in a systematic way and looking at all sorts of models and theories that can provide a handle on understanding.
But none of those models or theories will ever be the "truth". They can be adequate for the purposes needed, but outside of those limited areas, other models will be required. These other models will give a better description and handle within their limits. For all the desire for a "theory of everything", it will not be achieved. There will always be anomalous observations.
Whether you agree or disagree, that is simply your choice and anything I say will be seen through your filters and biases. That is what happens to all of us.
You can believe that GR is the "bee's knees", I can believe differently. You can believe in little blue fairies living at the bottom of your garden, if you like. I put little blue fairies in the same basket as "black holes".
We have lots of very interesting observations of lots of very interesting things out there. I just have problems with the inconsistencies of the models used to describe these things.
Do you believe in gravity? We've never observed it directly, always just its effects.
Can we use it, yes. But to believe that it is true, that is something quite different.
The science discussion about the existence is settled, as evidenced by your complete lack of any concrete objection to the interpretations. (Just saying "measuring is ambiguous, maybe we didn't understand it properly" like it is an objection is typical cranking)
I have no doubt that something was observed, but what that was will take far more research and repeated events that can be backed up by other observational means before we have any real evidence before us.
The science is only settled for those who want certainty in their models and theories. For practical uses, one can believe that electrons exist and act in particular ways and we build "technology" based on those "beliefs". Yet, we still do not have any real handle on what these particular entities are.
I used to believe in "black holes" and other assorted entities. I had no problems with these things, until I started noticing the discrepancies. It made me take a longer look and I realised that we know far less than we think and we understand far less than we think we do.
I live country that experiences climate change, yet, what I find interesting is that if you have questions about whether or not it is anthropogenic, you are immediately classified as a denier. The same goes for many different areas in science. If you don't accept the dogma you have to be a "crank".
What science needs is a higher level of scepticism than what it currently has.
Too many of the "settled" things are not "settled" at all. We have barely scratched the surface of the universe around us and the major failing we have is this desire to be certain. There are huge amounts of experimental observations that are showing that we really have no clue and an enormous number of new models are being developed as the years go by.
If you want to stick to reading Gorgias of Leontini that is fine, but please don't bother the rest of us that do accept the world outside as real.
We should be accepting that our models and theories are both incomplete and wrong, irrespective of how useful they are. Every model and theory has its points of failure. That should be expected and is not a problem. Starting from that basis, we keep investigating to get better models or theories that help us gain a better insight into the universe around us. If that means giving up one model for something completely else, then what's the problem. Our universe is beautiful, complex, a place of incredible wonder that we can have an exciting time exploring and discovery.
There is a vast difference between the reality of the universe and what our models and theories are. The first is the territory, the second is only a map and maps can be notoriously faulty.
In regards to your reference to Gorgias of Leontini, I had to look that up. I chuckled. Is it possible that some of the "superstars" of science today are modern students of him?
It is just assumed that the event horizon and all of the associated effects will occur in finite time. It is taken as a given that "Black Holes" exist without questioning all of the assumptions being made regarding these entities. When anyone questions this view, the amount of disdain and ridicule expressed to them is just ridiculous.
Those expressing such disdain and ridicule do not even attempt to answer the questions - it is immediate ad hominen attack. This is the attitude that encouraged me to investigate the matter further and the conclusion is that those experts who support the idea of "Black Holes" have a mindset of "we are the authority and who are you to question us". They are so blinded by there own brilliance that they cannot see the forest because they have their noses up against the ground. It is a sorry state of affairs when dogma gets in the road of investigation.
There are no stupid questions, ever. However, there are many non-answers given.
It seems like you're just placing restrictions on the term "black hole" that no one else is.
" An as-yet unpublished reanalysis by the same team using an updated list of 1,048 supernovas cuts the limit in half, to a maximum of about 23 percent, further slamming the door on the dark matter-black hole proposal. "
Since dark matter makes up 85% of total matter this rules out black holes as the primary contributor.
Get back to social mining you minions, you.
The supersolid dark matter displaced by a galaxy pushes back, causing the stars in the outer arms of the galaxy to orbit the galactic center at the rate in which they do.
Displaced supersolid dark matter is curved spacetime.
The Earth displaces the 'stuff'. The displaced 'stuff' pushes back. The displaced 'stuff' pushing back is gravity.
Curved spacetime = Geometrical representation of gravity.
Displaced supersolid dark matter = Physical representation of gravity.