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Biggest ever seen black hole jets; blasting plasma well beyond their own galaxy

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Re: Biggest ever seen black hole jets; blasting plasma well beyond their own galaxy

#61

Post by ks1723 »

gitanovic wrote: post #57
chasil wrote: post #51

Earlier quoted context omitted.

At that moment, why didn't the entire [mass of the] universe collapse into a black hole? Perhaps gravity evolved.

That's a question that I always also asked myself, from my layman understanding space time expanded quicker than gravitational collapse

Since there are conserved quantities like energy and angular momentum it is impossible that everything just collapses. If something collapses, there is usually a large amount of matter which does not collapse to carry away the energy and momentum of the collapsing stuff.

Re: Biggest ever seen black hole jets; blasting plasma well beyond their own galaxy

#62

Post by arbuge »

imranq wrote: post #10

The jets are 23 million light years in length! That's 140 milky way galaxies laid out -- these are sizes I can't even begin to comprehend

For comparison that's almost 10 times the distance to the Andromeda galaxy (2.5m ly).

Re: Biggest ever seen black hole jets; blasting plasma well beyond their own galaxy

#63

Post by edgyquant »

dyauspitr wrote: post #45
doctorwho42 wrote: post #42

Earlier quoted context omitted.

Actually, in theory there is one place denser but our models show it can never happen. The moment right after the big bang. As energy can never be created nor destroyed, all the energy in the universe was practically in one point in space-time a femtosecond after the big bang.

The whole concept of the Big Bang is a mind warp. The whole explosion must have happened in some… space-time thing to begin with. What was that immense point of matter and energy in? What was “around” it? We’ll never know.

Instead of thinking of it as a bang in an existing space-time, the way to conceptualize it is the collapsing of a universal wave function from a superposition of all possible universal states. Of which our universe is just one potential possibility. Space time is a function of the collapsing state.

Re: Biggest ever seen black hole jets; blasting plasma well beyond their own galaxy

#64

Post by Buttons840 »

ziddoap wrote: post #20
jadbox wrote: post #14

Earlier quoted context omitted.

Not my field, but could the Big Bang have been a massive black hole that "spat" out jets of plasma that formed into new stars and galaxies? I call this the black hole big burp theory.

This is very close to an idea known as "Black hole cosmology" -- basically the idea being that the visible universe is inside a black hole, leading to a sort of "nested multiverse". https://en.wikipedia.org/wiki/Black-hole_cosmology A related theory, rather than being inside a black hole, is that the other side of a black hole is a "white hole". As matter collapses into a black hole, it is emitted from the white hole…

In this "universe is inside a black hole" theory, is mass 1-to-1 with the "parent" universe? In this theory, are we inside a black hole containing billions of galaxies worth of matter?

An average black hole has 50 suns in it, 50 times the mass of our star, that would be a universe without much matter.

Re: Biggest ever seen black hole jets; blasting plasma well beyond their own galaxy

#65

Post by ziddoap »

Buttons840 wrote: post #64
ziddoap wrote: post #20

Earlier quoted context omitted.

This is very close to an idea known as "Black hole cosmology" -- basically the idea being that the visible universe is inside a black hole, leading to a sort of "nested multiverse". https://en.wikipedia.org/wiki/Black-hole_cosmology A related theory, rather than being inside a black hole, is that the other side of a black hole is a "white hole". As matter collapses into a black hole, it is emitted from the white hole…

In this "universe is inside a black hole" theory, is mass 1-to-1 with the "parent" universe? In this theory, are we inside a black hole containing billions of galaxies worth of matter? An average black hole has 50 suns in it, 50 times the mass of our star, that would be a universe without much matter.

To preface, this is not my field (space stuff is just an interest of mine), and this specific theory is more on the fringes than most so I haven't spent a significant amount of time thinking about it.

>is mass 1-to-1 with the "parent" universe? In this theory, are we inside a black hole containing billions of galaxies worth of matter?

My understanding of the theory is that the proposed parent black hole which our universe is inside would necessarily have to contain all of the mass that we detect in our observable universe. So our universe would be 1-to-1 mass of the parent black hole. The parent universe would be larger (and may contain many black holes, each with a nested universe).

>An average black hole has 50 suns in it, 50 times the mass of our star, that would be a universe without much matter

Indeed! It's interesting to think that perhaps we are on one of the "lowest" layers of the nested multiverse, and perhaps there are only a few dozen (or whatever) layers below us until there is too little mass in that universe to create any more black holes. However, there could be an infinite amount of layers "above" us.

I am curious to where the 50 solar-mass figure comes from, though. Is this excluding super-massive and ultra-massive black holes (which are on the order of 10^6 to 10^11 solar masses)? My intuition says 50 solar-masses is orders of magnitude too low for the average mass of a black hole, but I've never really looked into it

Re: Biggest ever seen black hole jets; blasting plasma well beyond their own galaxy

#66

Post by fasa99 »

takinola wrote: post #32
imranq wrote: post #10

The jets are 23 million light years in length! That's 140 milky way galaxies laid out -- these are sizes I can't even begin to comprehend

Imagine the amount of energy required to create a jet that large! The scales are so big, it makes me wonder if there isn’t an upper limit to energy density. How much energy can be in one spot before you inadvertently create a Big Bang?

[flagged]

Re: Biggest ever seen black hole jets; blasting plasma well beyond their own galaxy

#67

Post by dyauspitr »

edgyquant wrote: post #63
dyauspitr wrote: post #45

Earlier quoted context omitted.

The whole concept of the Big Bang is a mind warp. The whole explosion must have happened in some… space-time thing to begin with. What was that immense point of matter and energy in? What was “around” it? We’ll never know.

Instead of thinking of it as a bang in an existing space-time, the way to conceptualize it is the collapsing of a universal wave function from a superposition of all possible universal states. Of which our universe is just one potential possibility. Space time is a function of the collapsing state.

I think I understand that to a certain extent. But where does the universal wave function exist to begin with? There must be some construct it exists within.

Re: Biggest ever seen black hole jets; blasting plasma well beyond their own galaxy

#68

Post by trailynx »

thehappypm wrote: post #25

I have a question about black holes, HN. Let’s say you have a black hole. You fire a laser beam straight into it. Just by symmetry, shouldn’t it blueshift on the way in, gain some preposterous amount of energy — enough that it can escape?

You might enjoy the Halo Drive idea [0]. From my (very layman) understanding this uses this principle for propelling a spacecraft - you just need a moving black hole nearby :)

[0] https://arxiv.org/abs/1903.03423

Re: Biggest ever seen black hole jets; blasting plasma well beyond their own galaxy

#69

Post by itishappy »

thehappypm wrote: post #25

I have a question about black holes, HN. Let’s say you have a black hole. You fire a laser beam straight into it. Just by symmetry, shouldn’t it blueshift on the way in, gain some preposterous amount of energy — enough that it can escape?

> Just by symmetry, shouldn’t it blueshift on the way in, gain some preposterous amount of energy — enough that it can escape?

Escape requires a certain critical speed (escape velocity), and light always travels at the speed of light regardless of it's energy, so light's ability to escape a black hole is not energy dependent. At some radius (the event horizon), space itself falls into a black hole faster than the speed of light, and that's sets a hard limit on everything's ability to escape.

Past the event horizon physics get weird. Time becomes finite and ends for all observers at a point in the future called the singularity. Everything falls towards this point, gaining preposterous amounts of energy. "Preposterous" here means infinite energy, and infinite density, really just a whole lot of infinities. Those infinities are problematic, and mean there's probably something non-infinite and uniquely interesting going on in there, but since nothing can escape the event horizon we'll likely never know.

Re: Biggest ever seen black hole jets; blasting plasma well beyond their own galaxy

#70

Post by itishappy »

southernplaces7 wrote: post #5

I thought that only hawking radiation could escape a black hole. Now a paper describing a vast jet of emitted plasma?? The article doesn't quite clarify this point. It mentions the jets shooting from below and above the black holes, but does this mean they're emerging from their interior or being created by the accretion of superheated material that forms in orbit around black holes? The article simple states this, w…

> I thought that only hawking radiation could escape a black hole.

I think this is likely a misconception too. Hawking radiation does not come from inside a black hole, it comes from the event horizon. A virtual particle/anti-particle pair is created close enough to the event horizon that one of them falls in and the other escapes. This means the origin is outside the hole!

Similar story with jets. They're created by the interactions of matter as it falls towards the black hole (gaining energy), but before it actually falls inside.

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