Black Holes

[Dinnercore]

https://eventhorizontelescope.org/b...ent-horizon-telescope-be-presented-april-10th

Just dropping this here, we will see the first 'direct' picture of a black hole soon. Hopefully.

Or check in on the livestream 9 a.m. EDT https://www.nsf.gov/news/special_reports/blackholes/

 

[Caring1]

Dated April 1st hmmmmm

 

[dorsetknob]

https://www.msn.com/en-gb/money/tec...iverse/ar-BBVMH7r?li=BBoPWjQ&ocid=mailsignout

 

[lexluthermiester]

https://eventhorizontelescope.org/b...ent-horizon-telescope-be-presented-april-10th

Just dropping this here, we will see the first 'direct' picture of a black hole soon. Hopefully.

Or check in on the livestream 9 a.m. EDT https://www.nsf.gov/news/special_reports/blackholes/

It is going to be very interesting!
As a pretext, anyone curious should watch the following from Veritasium;

He gives an excellent explanation of how things work.

 

[delshay]

Here's the youtube Link

 

[biffzinker]

So we've went from this image the Hubble Space Telescope snapped back on July 6, 2000.

Now we have this image.

The first image of the environment around a black hole. As a matter of fact, it's not all dark.

https://arstechnica.com/science/201...-gives-us-first-images-of-what-its-named-for/

 

[SoNic67]

Hubble didn't had enough resolving power.
The minimum angle that we can see is dictated by the size of the collecting device (and wavelength/frequency captured).
Hubble has a 2.4m mirror and captures light (short wavelength).
This new result is equivalent to a capture device several thousand miles wide, but capturing radio signals, so it could resolve the actual hole while not being obscured.

 

[Animalpak]

well at the end the hollywood movies and documentaries they where right with the design.

 

[MrGenius]

So when you watch something fall into a black hole what do you see? Supposedly you see whatever it is get closer and closer to the event horizon. Moving slower and slower the closer it gets. Until when it reaches the event horizon it totally stops moving from your perspective. And even given an infinite amount of time to observe it, you will never see it move through the event horizon. It's stuck there forever. From your point of view anyway. While it has not actually stopped moving, but instead has actually passed through the event horizon from its perspective. And the reason for the discrepancy regarding what you observe has something to do with light travelling from the object taking an infinite amount of time to reach your eyes once it's passed the event horizon. So you can't ever actually see that happen. Which I sort of understand. What I don't understand is how a black hole is black then. How is it not a permanent collage of the images of everything that's ever fallen into it? When you look at it, you should still be able to see everything frozen at the event horizon then. Right?

But what happens when the black hole gets bigger? The event horizon expands? Or does it not? What happens to the things you're not able to ever see go through the event horizon then? Does the event horizon move outward past them? Or do they move outward with the event horizon?

There's never a shortage of WTF when it comes to black holes.


"It's a good thing to keep an open mind. But not so much that your brain falls out."

 

[hat]

Nice most @MrGenius. You raise some excellent points.

They say this black hole in particular is approximately the size of the solar system? That's nuts. Must have been one hell of a star to leave behind such a large black hole.

 

[biffzinker]

They say this black hole in particular is approximately the size of the solar system? That's nuts. Must have been one hell of a star to leave behind such a large black hole.

https://xkcd.com/2135/

 

[lexluthermiester]

They say this black hole in particular is approximately the size of the solar system? That's nuts. Must have been one hell of a star to leave behind such a large black hole.

That's actually a misunderstanding. It started out as a generally standard "size"(mass) black hole and has gained mass through matter absorption and merging with other black holes over many billions of years.

 

[Caring1]

So when you watch something fall into a black hole what do you see? Supposedly you see whatever it is get closer and closer to the event horizon. Moving slower and slower the closer it gets. Until when it reaches the event horizon it totally stops moving from your perspective.

That doesn't make sense to me.
Logic dictates that the further away an object is from the black hole, the less effect it would have, and therefore it would move slower.
It's like watching water go down a sink, the outer edges are slow in the whirlpool, the inner edge the fastest.
reaching the event horizon shouldn't make an object appear to stand still, in fact it should just "go over the edge" and disappear.

 

[lexluthermiester]

Until when it reaches the event horizon it totally stops moving from your perspective. And even given an infinite amount of time to observe it, you will never see it move through the event horizon. It's stuck there forever. From your point of view anyway. While it has not actually stopped moving, but instead has actually passed through the event horizon from its perspective. And the reason for the discrepancy regarding what you observe has something to do with light traveling from the object taking an infinite amount of time to reach your eyes once it's passed the event horizon. So you can't ever actually see that happen.

That actually isn't the way it works. What you are talking about is the dilation of time by the effect of the gravity well. Matter appears to slowdown from the perspective of the outside observer when in fact matter accelerates to nearly the speed of light as it moves closer to the center of the gravity well. The event-horizon is not an actual object. It is a boundary. A distance threshold away from the actual black-hole mass object. Any particle moving inward toward the gravity well beyond that boundary will not be able to escape and will no longer be observable from outside of said boundary. This boundary is not a set distance away from the actual mass object. As the back-hole gains mass, the gravity well become stronger and as an effect the boundary moves further outward and away from the mass object creating it.

So as matter approaches the event horizon boundary, it appears to slow down from the perspective of outside observer. This is of course not happening. The matter in question simply continues moving inward toward the black-hole object until it is absorbed. This motion does not stop as it crosses the event-horizon boundary. All that changes is the ability to observe such motion from beyond the boundary. The matter falling in just keeps going.

That doesn't make sense to me.
Logic dictates that the further away an object is from the black hole, the less effect it would have, and therefore it would move slower.
It's like watching water go down a sink, the outer edges are slow in the whirlpool, the inner edge the fastest.
reaching the event horizon shouldn't make an object appear to stand still, in fact it should just "go over the edge" and disappear.

While this is true, gravity has the effect of dilating(or slowing) time. So from the perspective of the outside observer, things(matter & energy) appear to slow down as they approach the event-horizon, but this is only an illusion. As described above, there is no "edge" to go over. Just a boundary from which there is no escape velocity fast enough to move beyond. The irony of a "Black-Hole" is that it is only "black" from the outside of the boundary of the event-horizon. Inside that boundary it is actually extremely bright and intensely hot. This is because all of the EMR has no where to go except orbit the mass object at the center until it is absorbed, which takes a lot of time. The intensity is so great that if you were to manage getting inside the event-horizon in one piece, you would be ripped apart within trillionths of a seconds from effects of intense EMR.

 

[kapone32]

That doesn't make sense to me.
Logic dictates that the further away an object is from the black hole, the less effect it would have, and therefore it would move slower.
It's like watching water go down a sink, the outer edges are slow in the whirlpool, the inner edge the fastest.
reaching the event horizon shouldn't make an object appear to stand still, in fact it should just "go over the edge" and disappear.

Theoretically speaking a black hole should behave in the same way as our sun in relation to objects being closer orbiting faster. The main difference being that instead of stable, the gravity well from the black hole would initially slow down the objects orbiting it by pulling them in until they reach the point where they begin to accelerate. Super Massive Black Holes like the one in the centre of our galaxy are not usually found anywhere other than the centre of galaxies and as such act the same way as the sun does to cause whatever is around it to orbit as evidenced by the spin of our galaxy even if it is on a scale that no one alive can actually see. Even the Sumerians could not have seen a different night sky than what we see today.

 

[MrGenius]

That doesn't make sense to me.
Logic dictates that the further away an object is from the black hole, the less effect it would have, and therefore it would move slower.
It's like watching water go down a sink, the outer edges are slow in the whirlpool, the inner edge the fastest.
reaching the event horizon shouldn't make an object appear to stand still, in fact it should just "go over the edge" and disappear.

Watch this.

Then check this one out @ around 7:00, for another explanation of why.

 

[Bones]

Just bear in mind everything we "Know" is based on observation from where we are relative to a Black Hole and it's mostly speculation, not fact at this point.

I'll be honest, anyone that says "This and that" is happening within a Black Hole doesn't truly know much of anything about it. The only real way to know and confirm things as fact is to go in and see firsthand, at least we do know the outcome of such an attempt.

As to what we really know, well...... We're still learning about things here on Earth too.

No way we could possibly know all that about something so far away based on pure observation and theory alone because you can discover only so much that way, much of it IS speculation and nothing else. I do agree to speculate isn't a bad thing but you still have to remember the circumstances in which said observations and such are made. The only true way to know would be to go there and see it all firsthand, a good example is when Pluto had it's first visit from a probe just a few years ago.....

Look at all the things we didn't know before about Pluto that's known now, and even with that there is still so much we've yet to discover about it.
All I'm saying here is keep it real.

 

[MatGrow]

What's at the centre of most large galaxies, then?

I don't believe in that first image of black hole. I don't believe it's real one.

 

[lexluthermiester]

Here's another vid that is really interesting.

 

[MrGenius]

I don't believe in that first image of black hole. I don't believe it's real one.

Some people refuse to believe in reality. Doesn't make it any less real.

"When it's them, it's them, it's them...it's really you."

If everything is lies and conspiracies, it's because you need it to be that way. You can't accept that someone else knows something that you don't. So you just insist it can't be true. Problem solved? Nope. Problem created.

 

[lexluthermiester]

Some people refuse to believe in reality. Doesn't make it any less real.

"When it's them, it's them, it's them...it's really you."

If everything is lies and conspiracies, it's because you need it to be that way. You can't accept that someone else knows something that you don't. So you just insist it can't be true. Problem solved? Nope. Problem created.

Actually, I think MatGrow meant that the image itself was computer generated. I don't think he was saying that Black-Holes don't exist.

 

[MatGrow]

Some people refuse to believe in reality. Doesn't make it any less real.

"When it's them, it's them, it's them...it's really you."

If everything is lies and conspiracies, it's because you need it to be that way. You can't accept that someone else knows something that you don't. So you just insist it can't be true. Problem solved? Nope. Problem created.

I agree with you.
But to believe it or not doesn't change your life.

 

[lexluthermiester]

I agree with you.
But to believe it or not doesn't change your life.

Maybe not, but this is amazing progress and equally fascinating. Science marches on.

 

[FCG]

I also have a hard time understanding what he writes, but that's because I can't visualize in my head this "scalar motion" he mentions.

Now, if this scalar dimension was, somehow, a completely reversed image of our universe, say, like when in the movie Interstellar, Cooper's Ranger is entering

Spoiler

Gargantua and we see the cosmos looking like a wormhole,

maybe that's what this scalar reference frame could be: some sort of mirror dimension where the edge is at the center and the core is around it?

Ok, maybe I figured it out.

If space was expanding at lightspeed, but anything which had mass was dragging itself back, it would collapse into various types of celestial bodies (stars, planets, ...), but anything without mass would be dragged by the expansion of space at lightspeed (light).
This way, light is not really moving on its own, but pulled by the expanding space, and we get hit by light because we're way slower than space, due to our mass.

Behold. A man opens his eyes and for the first time sees.

Can’t say this is perfect although you have set a foundation.

Gravitational “direction” is inward in space (outward in time). As light does not move relative to the moving natural reference frame, gravitating objects (matter) overtake these locations in time. I see light.

Exactly. General/Special Relativity predict that the universe should be slowing down and even contracting at this point in history, but that is not what we observe.

It will reach c, the “speed of light,” the default speed of the universe.

We are observing outward scalar motion between all points from the perspective of a fixed 3D spacial reference frame that we call reality. We are inside a gravitational limit. That motion is scalarly away from ALL points (conjugate of gravity).

Again, we have a name for this. The Hubble Expansion

Except that there is but one problem with that logic; The universe has been observed to be expanding at a rate greater than the speed of light, by more than double.

This has been addressed. Doppler shift, Red shift, same principle, are explained by motion in time in addition to motion in space.

I would suggest you stop arguing why something can’t be and start asking ‘HOW can this be?’

 

[Drone]