@tio
> But singularity is weird and still just an assumption isn't it? What is a point?

I don't know man, they're just super weird. I think the singularity idea was proposed because its gravitational pull is so strong that it pulls light and swallows it, I don't think a star can do that.

My understanding about black holes are pretty basic & I haven't read any of these proposed theories. I think the singularity idea & the general theory of relativity are more widely accepted, IDK.
@tychosoft

@futureisfoss @tychosoft Yah ofc they are weird, I just entertained an idea I had. It is a fun discussion. But to have answers you need to do science, and that I cannot :D . I love these mysteries.

@tio
Yeah, its fun to think about stuff like this, I used to do that all the time. But without doing the actuall science, all we do is kinda like a philosophical pondering of the endless possibilities, its still fun though 🙂
@tychosoft

@futureisfoss @tychosoft oh no not the word "philosophical" hahaah. We are just curious. :D thats all.

@tio
Does the word philosophy confuse you ? Haha, I'm just curious 😄
@tychosoft

@futureisfoss @tychosoft It is very much associated with the field "philosophy". Which I hate since it is a lot of bla bla bla. You can't murder every interesting conversation by calling it philosophy haha. It is simply an interesting conversation. I don't want to talk about reason, and logic, and nonsense concepts :D - i am just allergic to that word.

@tio
We try to categorize things into different topics. This is sometimes helpful, like if someone said they're interested in physics and someone else is interested in chemistry, we'll have a rough idea of what they mean. But often times we can't really categorize everything into one or the other. Like asking if a hyena is a dog or a cat ? We invented these words like cat & dog, they're not real.
@tychosoft

@tio @tychosoft
I don't know if it should be called philosophy, but there should be a word for things that cannot be disproved, but can't really be proved either. There are people who argue that free will is an illusion, and some others say we might be living in a simulation. There's no way to disprove these theories, we can only just ponder about them.

@tio @tychosoft
"Problem of other minds" is a perfect example of this, since there's no way to prove/disprove it. This is similar to the question "Is your red the same as my red?", Vsauce did a video about this problem - https://www.youtube.com/watch?v=evQsOFQju08

You're right, these might be a bit "bla bla bla", its still quite interesting to think about. They really show us our limitations, we can't know the answer to everything.

@futureisfoss @tychosoft Yes but philosophy means very much nothing of essence. And we talk about categorizing not animals and such, but discussions, which is even more abstract. It is great to think and come up with ideas about whatever you like, but to make a "category" out of these is too much for my personal comfort. I do not think it helps :P .

@tio
Yeah, maybe trying to categorize discussions is not that great. There are times where these could be useful, like the example of physics & chemistry, but it doesn't mean anything other than a rough idea of what we're talking about.

I don't know if there's any reason to be against the field of philosophy, that Vsause video I sent you earlier is pretty philosophical, but I can't say I never learned anything from it :)
@tychosoft

@futureisfoss @tychosoft Well I had several discussions with people who studied "philosophy" and they all ended up very badly with them bla bla blaing so much that even they got confused. Maybe my distaste comes form there.

@tio
I've never talked with anyone who've studied philosophy, so I don't know. Because a lot of these are just speculations, I assume a lot of shitty theories might've ended up in this field, haha. But if you talk talk to the right person, I think every field can be interesting ;)
@tychosoft

@futureisfoss @tychosoft idk...philosophy to me, from what I've read about it, is a confusing and bla bla bla field. But I am sure there are interesting aspects of it.

@tio
Its not actually a hole, you know that right. It just pulls everything in to the singularity, that's just an extremely powerful gravity. And for where does this matter go, there are theories saying its like wormhole, so it spews everything it swallows somewhere else. There's also Hawking radiation, which is more widely accepted I think. It solves this information paradox, because it shows that black holes radiate away.

@futureisfoss Well they call it a hole...I know is not like a normal hole. But as far as I understand it doesn't spew what it swallows somewhere else since you can see it growing and account for the stuff it swallows. The Hawking radiation is simply a proof that they also lose "stuff". Stuff gets out. And probably that's normal matter since we can "see" it.

"It just pulls everything in to the singularity" - so you're saying it pulls stuff into that "point"? Then why are these black holes bigger, smaller, have a shape, a mass? I don't get it :D

@tio
"It just pulls everything in to the singularity" - so you're saying it pulls stuff into that "point"? Then why are these black holes bigger, smaller, have a shape, a mass?

I'm no expert, but from what I understand, what they mean by the size is the event horizon. The event horizon is a boundary inside which light can no longer escape. So intuitively, this event horizon should expand when the mass increases because gravity increases with mass.

@futureisfoss hmm isnt the event horizon the boundary between that dark circle (what i call as the black ball) and the visible matter? Something like this_


And the entire black disk is that "singularity"? Maybe I am confused....

@tio
This video explains it very well - https://www.youtube.com/watch?v=QqsLTNkzvaY

Its really interesting cause there's a lot we don't know about black holes, maybe the truth is even more weirder than our theories, haha.

@futureisfoss Yup very good video. Explains very well. However considering that it is is difficult to understand these monsters even my theory may end up being correct haha. In the end doesn't matter at all, what matters is that these exist and are mind blowing.

@tio
Yeah, like I said, the reality might be even more crazier that both of our theories, lol 😂

@futureisfoss It very likely is!

@tio
BTW, from what I know about black holes, they don't have a shape. I've heard about spinning black holes, but never a cube/pyramid shaped one 😁

@futureisfoss Well we can't observer them, remember!? But we can observe the outer side of them when they have lunch, and we for sure see a disk-like shape. Which can, in fact be spherical.

@tio
Oh yeah, the singularity might be of any shape, we don't really know much about the inside, everything after the event horizon is just black

Most black holes I've seen in pictures and stuff have a spherical event horizon, and I think the disk you're mentioning is things orbiting these black holes that glow because of their heat, that video explained it. If the event horizon is spherical, the stuff inside should be spherical too right ? I don't know enough about gravitational fields to know

@futureisfoss

Oh yeah, the singularity might be of any shape, we don't really know much about the inside, everything after the event horizon is just black

Could also be that there is no such thing as singularity...

If the event horizon is spherical, the stuff inside should be spherical too right ?

Sounds right to me but how can we know :D. If I think about my black ball theory then yes haha.

@tio
> Could also be that there is no such thing as singularity...

Could be, but the mass of the black hole still has to exist somewhere inside the event horizon. The idea of a singularity is probably used to explain the extreme gravitational pull, maybe it'll have less space-time curvature if the mass is spread around VS on a densely packed point. So more space-time curvature means more gravity. I'm still not sure how scientifically proven this singularity thing is, this is my understanding.

@futureisfoss Isn't a star that's 1km in diameter and has 1 tonne mass, having the same gravitational pull of a star that's 10km in size and still 1 tonne?

@tio
Yeah you're right, the gravitational pull will only differ with mass and distance, I was thinking of the spacetime curvature analogy.

@tio
But if you think about it, size does make a difference. If you're falling into a 10km size star with 1 tonne mass, you'll experience the same gravitational pull as a 1km size star with the same mass. But remember, gravity increases when distance between you and the star reduces, so you'll keep on accelerating as you move closer to the star. So on a 10km size star, the closest you can get to it is 5km (its radius). But on a 1km size star, you can go up to 0.5km where gravity is stronger 🙂

@futureisfoss I think this video explains it well www.khanacademy.org/science/co… - if am object is much smaller but has the same mass, then an object can get closer so the gravity is much stronger. But now we know that even the black ball, what they call as event horizon , is much smaller than a star. So it is already insanely dense and small. Like crushing multiple stars in a few km round object. Now what they are saying from what I understand from you, is that this mass of a black hole is not that black disk we observe, but a tiny point in the middle. This sounds very insane haha. Might be true tho, but insane. My black ball theory sounds less insane in that regard :D

@tio
That video is talking about the same thing I said earlier. So its confirmed, dense objects have higher gravity 🙂

> this mass of a black hole is not that black disk we observe, but a tiny point in the middle.

Of course, the event horizon is not a physical boundary like the boundary of a ball, its a point after which light can no longer escape from the gravity of the black hole. And gravitational field is always much larger than the size of the object, think about sun pulling on earth.

@futureisfoss

Of course, the event horizon is not a physical boundary like the boundary of a ball, its a point after which light can no longer escape from the gravity of the black hole.

At least thats what they theorize ;)

And gravitational field is always much larger than the size of the object, think about sun pulling on earth.

Same for a black hole, it extends far more than that dark disk (ball).

@tio

> At least thats what they theorize ;)

I don't know if its just a theory, what's happening inside a black hole we can't know, but we can observe the surroundings to prove that there's extreme gravity there that even light can't escape. Remember, light only moves in a straight line, but massive objects can bend the space-time curvature to bend its path. This has been proven, I recommend you look more into general theory of relativity, its very interesting :)

@futureisfoss hahaahha no no i am familiar with that. but maybe there is a very dense ball from which light can't escape, or maybe it is made out of dark matter and we don0t know wtf that is :).

@tio
https://www.youtube.com/watch?v=0sr1Xeocuuc

I've been thinking about this video you sent me....... And I think I get it now, I understand why they theorized singularity to be a point. This is even more stranger & weirder than I thought, haha.

@tio
So when a star dies and it collapses under its own gravity, 3 things can happen. If the repulsion between electrons are able to prevent the collapse, then it becomes a white dwarf. If the repulsion between neutrons stop the collapse, then it becomes a neutron star. But if the star is too massive and even those nuclear forces can't stop the collapse, then there's no other force known to science that can stop it from collapsing on its own. So it collapses into an infinitely dense point !

@tio
Just think about that for a moment, this is one of the craziest shit I've ever heard, and its hard to believe these things actually exist ! 😲

Its really hard for me to grasp this concept, because its so different from everything I've experienced in my life. My intuition tells me that if more stuff gets sucked into the black hole, the singularity should get bigger. But it doesn't !

@tio
The reason why we can't compress everything into a point in real life is the same reason why I can't push my hand through the wall. The atoms/electrons in my hand repulses the atoms/electrons in the surface of the wall. But inside the black hole, the gravity is so strong that it overcomes these repulsion between atoms, so there's no other force to prevent it from collapsing into a point.

@tio
No matter how much stuff you throw into a black hole, the singularity will remain the same size. The mass of the black hole will increase and thus the gravity increases, so the event horizon will get bigger. But the actual size of the singularity won't increase, it'll just collapse everything into that infinitely dense point. This is just insane 🤯

@futureisfoss

My intuition tells me that if more stuff gets sucked into the black hole, the singularity should get bigger. But it doesn't !

Maybe it does....

@tio
I don't think it does, haha. I know its a little hard to understand but that's what makes black holes interesting, its not like anything we've seen before.

@futureisfoss Yes but what if under that tremendous pressure it creates dark matter? :) I dont see that as a wild idea.

@tio
If you're saying tremendous pressure can turn matter into dark matter, yeah it sounds plausible. This would also explain why stuff pulled into the black hole also become dark matter, because one thing that black holes and a collapsing star have in common is pressure ;)

I still have some doubts as to what happens after it turns into dark matter, but considering how little we know about them I don't think there's any point in us arguing over what "might" be happening, lol 😅

@tio
That disk shape could also be something called "gravitational lensing" which happens around the event horizon. Its kinda weird TBH, crazy things start to happen when the gravitational pull is so high !

@futureisfoss Thanks for engaging I learned more things because of that. I wsn't aware that they are saying that a black hole is a black nothing but its mass is in a very dense center thats super small. I had the wrong impression that the black hole is the entire black thing. Maybe that's what made me think about it being a black ball. These two videos explain it well:

ytb.trom.tf/watch?v=poE8CuucCE…
ytb.trom.tf/embed/0sr1Xeocuuc

Although I will have to update my theory ( :)) ) it still may be wrong the way they are theorizing about it now. Maybe there's still a black ball instead of a black hole, and it is made of a different type of matter, maybe even dark matter.

You did great at explaining this, and I am very happy you have engaged in such a discussion :).

@tio
Those 2 videos are very good 👍

My confusion regarding this black balls theory is this:

1. Not even light can escape a black hole because its so dense that the gravity is in the extremes. But if it was a ball the same size (of event horizon), then it wouldn't be this dense and wouldn't have that much gravity

2. We don't even know if matter can become dark matter, let alone say that stars exploding will cause it. Its called dark matter cause we literally know nothing about it, lol 😂

@tio
Thank you for engaging as well, we could discuss these things for hours without getting bored, haha 😄