/sci/ - Science & Math

[Black holes No.6621672]

What are black holes?

[Anonymous No.6621676]

An extremely dense and infinitesimally small point in space.

[Black holes No.6621677]

>>6621676

What is it made of and why does it make light go faster than light towards it?

[Anonymous No.6621678]

>>6621677
It's a curvature in space. So it's just a result of that curvature.

[Anonymous No.6621679]

>>6621676
>extremely dense
Is /sci/ a black hole?

[Anonymous No.6621683]

>>6621679
not yet , for /sci/ to be a black hole you would have to compress it into a single post.

[Anonymous No.6621685]

>>6621679
4chan in general is a shithole.

[Anonymous No.6621687]

>>6621683
> My sides pulsate with the fervour of a thousand galaxies.

[Anonymous No.6621694]

>>6621672
so 5 minutes ago
>>white holes
http://en.wikipedia.org/wiki/White_hole

[Anonymous No.6621700]

>>6621694

A black hole was a white hole? Does that even exist in this universe?

[Anonymous No.6621796]

>>6621700
uh...
hold on..
I'm still trying to come up w/a good response

[Anonymous No.6621807]

>>6621683
>barnetts identity.jpg

[Anonymous No.6621815]

>>6621672
the most massive stars become black holes when they die. there's no more fussionable matter to burn and gravity wins over outwardly-pushing forces, even the forces that make atoms stable. So this massive object compresses to an extremely small volume, and the associated space-time curvature is extreme, even to the point of attracting and absorbing fast surrounding objects, like photons (light)

[Anonymous No.6621827]

>>6621815

Black holes are indeed strange phenomena; nothing can ever go faster than light, unless it is goes into a bakc hole's event horizon and starts falling towards it faster than light.

What are black holes made of, by the way?

[Anonymous No.6621833]

>>6621827
>starts falling towards it faster than light
no...

[Anonymous No.6621846]

>>6621833

Does an object that has crossed a black hole's event horizon go slower than light, then?

[Anonymous No.6621873]

>>6621846
yes

[Anonymous No.6621875]

>>6621846
Yes
They can't ever reach the speed of light, so since orbital velocity is faster than the speed of light, which the particle can't reach, it'll just spiral inwards at an ever-increasing rate

[Anonymous No.6621879]

>>6621873

So light actually escapes from balck holes?

[Anonymous No.6621886]

>>6621879
Don't be stupid

[Anonymous No.6621887]

>>6621879
Since the black hole's gravity can't speed up or slow down light, since it can only go at the speed of light, then outside the event horizon, where orbital velocity is below the speed of light it'll spiral outwards at an increasing rate until it escapes, and inside the event horizon, where orbital velocity is above the speed of light, it'll spiral inwards at an increasing rate
At the event horizon, where orbital velocity is exactly the speed of light, light will just orbit the black hole

[Anonymous No.6621888]

>>6621827
>>6621833
Actually, yeah. The event horizon is the place where escape velocity is 'c' so, an object initially at rest on the event horizon would reach the speed of light at the center of the 'hole'.

[Anonymous No.6621893]

>>6621888
Under Keplerian orbital mechanics, yes, they would
Kepler's laws don't account for relativity, though

[Anonymous No.6621897]

>>6621893
Well it's not 'Kepler's Laws', rather Newtonian gravity but yeah, you're right.

[Anonymous No.6621901]

>>6621897

OP here.

Yeah, I actually wanted an explanation based on Newtonian mechanics but I think that's impossible because no one really gives a shit about obsolete models, not in this board.

[Anonymous No.6621925]

>>6621901
I don't think black holes, as we know them, can really exist under Newtonian mechanics
The main defining feature of one is that nothing can escape it, once they go below a certain point, while under Newtonian mechanics there's nothing stopping an object from taking a dive below the event horizon going at FTL speeds and coming right back to where it started

[Anonymous No.6621933]

>>6621901
On newtonian mechanics there is no such thing as a velocity limit (speed of light), you can't expect to ask a relativity question, for a relativity object and expect an answer in newtonian mechanics.

[Anonymous No.6622056]

It turns out that that fluid dynamics and turbulence models are actually capable of predicting the precise mass of a black hole. This description suggests that a black hole is actually a vortex of space/time produced by the effects of gravity collapsing in toward a point.

The reason it appears to collapse toward a point is an easy to understand as flushing your toilet. The mass of the star expands outward and forms a high density accretion layer of mass in the shape of a halo while the interior collapses. The high density interior core attracts the halo mass. The halo mass also attracts the halo mass. As the halo mass tries to converge back upon itself, the collapsed core introduced curved relativistic space to the path. This in turn produces a curvature in the path of collapse for the halo. The net result is the halo mass enters a decaying orbit. The mass of this decaying orbit is itself sufficient to curve space and itself curving toward a point in space. The final result relativistic curvature of space in the form of a vortex.

Black holes don't magically gain mass, they just create a giant detour for anything that gets too close.

[Anonymous No.6622058]

>>6621700
it's Portal, but with singularities and it's only one way

[Anonymous No.6622089]

>>6621887
>At the event horizon, where orbital velocity is exactly the speed of light, light will just orbit the black hole

this is called the photon sphere.

[Anonymous No.6622167]

>>6622056
I don't think anyone here thinks black holes magically gain mass

Though I could be thinking a bit too optimistically of the people of this board

[Anonymous No.6622352]

>>6622089
Strange that the event horizon is below the photon sphere..

also light does escape from the poles?

[Anonymous No.6622365]

>>6622167
weight and gravity are correlated?

[Anonymous No.6622380]

>>6621672
A region of space with sufficient mass and density that its escape velocity exceeds the speed of light. The result is that nothing, not even light, can escape this region, creating a "black hole" from which no light is emitted and which devours all matter and energy.

According to attempts to combine quantum theory and relativity, black holes may actually be able to emit energy through Hawking radiation; however, this is very small.

It is theorized that the center of a black hole contains a "singularity" , or infinitely dense point of nonzero mass and zero size. This is because the gravitational crushing force at the center of a black hole is so great that no known resisting force could overcome it, and so matter is thought to entirely collapse.

However, it is believed that there is probably an ultimate resisting force that prevents matter from entirely collapsing to zero size, but we don't know what it is. Understanding what goes on at that level would require a combined theory of quantum mechanics (to understand the behavior of matter at such small scales) and relativity (to understand the behavior of matter in high gravity and bent spacetime). We don't have such a theory, so we don't really know what's really going on inside a black hole.

[Anonymous No.6622390]

>>6622380

Lagrangian vortices make infinitely more sense.

http://livasperiklis.files.wordpress.com/2013/09/coherent-lagrangian-vortices-the-black-holes-of-turbulence-cambridge-journals.pdf

[Anonymous No.6622412]

>>6622365
The energy confined within mass produces a curvature of space around it.

>>6622352
Ultra high energy bursts radiate from the poles because it's a vortex formed by the relativistic curvature of the mass in the plasma at the interior of the star collapses distributing toward itself and the surface along a plot of phi^pi.

Vortex plate is the accretion disc and the funnel at the pole is the point of gamma ray emission. The ultra high compression of space from the vortex curvature of space reaches a decompression point where the compressed energy of the accretion disc is radiated. the distinction between Lagrangian vortex and a magnetic pole is that magnetic poles always have + and -. Gravitational vortices are monopoles. Giant. Fucking. Monopoles.

[Anonymous No.6622437]

>>6622365
Weight =/= mass
If an object on Earth weighs 10kg, then it weighs 1.6kg on the Moon, and 0kg in LEO
If an object has 10kg of mass, it still has 10kg of mass no matter where you are

[Anon No.6622441]

>>6621888
No. As anything approaches the speed of light, the energy required to accelerate it increases. To actually reach the speed of light, an object would need infinite energy, which a black hole does not have.

Besides, if things went faster than light under the event horizon, some objects would be slingshotted outward because of the literally impossibly fast speeds allowing them to reach escape velocity.

[Anonymous No.6622447]

>>6622437
>and 0kg in LEO
Even at the upper bound for LEO, 2Mm, you still feel about 5.7 m/s^2 of acceleration due to gravity,

[Anonymous No.6622449]

>>6622447
If you're in orbit, you're in freefall. No measured weight.

[Anonymous No.6622525]

>>6622441
That might depend on how much space is `inside' the black-hole?

I wonder what stops a black-hole from turning all it's matter into energy... or maybe it does =)
but then why is the energy still trapped?

[Anonymous No.6622624]

>>6622525

Gravity dude, all that shit in there is heavy

[Anonymous No.6622628]

>>6622525

[Anonymous No.6622642]

>>6621672
Gravitational anomalies.
Very massive stars collapse under their own gravity when they run out of hydrogen. They collapse into a singularity. They're basically superdense pieces of matter. Thus, they have stupidly strong gravitational fields.
They're not wormholes like people think..They don't go anywhere, you're just ripped up by gravity.

[Anonymous No.6622643]

>>6621677
Light doesn't go faster than light near it. It just bends. Just like it bends around planets. Just much more so with black holes because their gravity is much stronger.

[Anonymous No.6622648]

>>6621827
They're not made of anything. They're just areas of high gravity. At the core is the matter the parent star was made of. Helium, carbon, iron etc. But it doesn't matter what elements are in it, chemistry can't take place under those conditions..

[Anonymous No.6622651]

>>6621887
That's the photosphere radius, not the event horizon.

[Anonymous No.6622708]

>>6622525
Energy in what form?

[Anonymous No.6622730]

>>6621672
Other universes

[Anonymous No.6622904]

>>6621887
How does light actually get inside the event horizon? Wouldn't it always just first begin spiraling outwards since it'll always have to "go through" the event horizon, and so be outside of it?

[None !SSDoCt0rTo No.6622905]

negative light. next question please

[Anonymous No.6622958]

>>6622904
Hooray, ms paint diagrams

[Anonymous No.6622981]

>>6621679
a black hole is defined as a region in space where the escape velocity is c or larger.

>4chan
>escape
>larger than c

seems legit.

[Anonymous No.6623026]

>>6622904
The event horizon isn't a barrier, it's just a region around a black hole.

[Anonymous No.6623115]

>>6622628
>fluid
so a white hole fixes the problem of why the universe prefers disorder?

[Anonymous No.6623140]

>>6622958
>yellow letters and lines with white background

smart biatch niggah!

[Anonymous No.6624577]

>>6622628
You know... This makes a lot of sense...