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View Full Version : Creating one's own black hole -- how to?

Lindon
2009-Oct-19, 04:38 PM
Last night I watched a science program re-run, and in one of the segments there was a guy holding a marble (I think) in his hand, explaining that if we could shrink the mass of the earth down to the size of this (marble), then it would have the density required to create a black hole. But, is density the sole requirement for creating a black hole? We all know that the spacetime fabric is flexible, and that it takes an extreme mass in an extremely condensed form to penetrate into the spacetime fabric. But didn't Einstein say something to the effect that acceleration and gravity are the same thing? The point I'm trying to make, and the question I'm trying to ask is, isn't it possible to replace mass with velocity to a certain extent to create a black hole? In other words, a solid object doesn't have enough mass to penetrate the spacetime fabric, but if that same item was accelerated fast enough, would it possibly be able to penetrate the spacetime fabric? I read through about half of the Questions and Answers forum and couldn't find this question previously asked -- I hope I'm not resurrecting an old question here. Thanks!

neilzero
2009-Oct-19, 06:47 PM
As far as I know density is the sole requirement to make a black hole. Velocity may help create enough density. I don't think gravity and acceleration are the same thing and likely Einstien did not say that when he was sober. I have not heard the "penetrate the spacetime fabric hypothesis" and am suspicious it has no basis. Neil

eburacum45
2009-Oct-19, 07:10 PM
The answer is, velocity does not create a black hole alone.
http://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/black_fast.html

Making an artificial black hole would be a remarkably useful achievement; miniature black holes could be used for power generation, and perhaps for other, more esoteric uses as well. But they seem to be very difficult to make- according to Hawking, making a black hole would require an accelerator the size of a galaxy (assuming magnetic fields at strengths available today).

However some people think there may be other ways of doing it;
http://www.nytimes.com/2001/09/11/science/physicists-strive-to-build-a-black-hole.html?pagewanted=all
...time will tell.

Lindon
2009-Oct-19, 07:32 PM
Thanks for the links eburacum45 -- verrrry interesting. I had heard that scientists are theorizing (speculating) about the possibility that tiny particle-sized black holes might be created with the Large Hadron Collider once they get it up and running, and I had assumed that they were counting on the velocity of the impacting particles to precipitate the creation of the mini-black holes. It does appear we'll just have to wait and see. Note to neilzero: I heard that attribution to Einstein last night on one of the History Channel "The Universe" re-runs, which is where I get ALL my information about the universe and physics -- well, at least I did until I came to this forum. I may have misunderstood. On a final note, from a layman's perhaps dim-witted point of view, I've seen "fabric" that when stretched tight can flexibly bend under a relatively enormous weight without breaking, but when a small object (i.e., .22 round) is "accelerated" onto the fabric, it definitely penetrates. I guess that's the difference between synthetic fabric and spacetime fabric. Thanks for the feedback.

Durakken
2009-Oct-19, 09:54 PM
Lets say...
Size of the Planet = 1
Gravity of the Planet = 1
Density of the Planet = 1

If density goes up to 2
Size of planet must be reduced to 0 if gravity remains 1

If density goes down to 0
Size of planet must increase to 2 if gravity remains 1

If Size goes up to 2 and density remains at 1
Gravity must go up to 2

So, If we take a planet and decrease it's size to a marble through making it more dense the gravity will remain the same, however because we can get closer to the center of gravity it appears to be stronger.

Lindon
2009-Oct-19, 10:05 PM
And in that case, since the density is so great in relation to the size, the spacetime fabric can't support our marble-sized planet anymore, and so it sinks (penetrates deeply -- or all the way through) the spacetime fabric -- right? I figure there must be some equation that describes the density-to-size ratio that must exist in order for a mass to sink into the spacetime fabric, black-hole style. Or was the guy on TV just making it up?

cosmocrazy
2009-Oct-19, 10:33 PM
Well we are not exactly sure what happens to the energy and matter trapped inside a black hole. The definition of that hole is in its title "black" which in turn means that the gravity of the object is so strong that the escape velocity is greater than C, even light can't escape so it becomes extremely difficult to extrapolate any information about what's beyond the event horizon. The math suggests that at the centre of this hole lies a "singularity" the definition of which has no physical meaning (a point which occupies no space/time as we know it). What we do know is that at a point of critical mass density the gravity would be so strong that it would simply continue collapsing together until this BH was formed (Schwarzschild radius, R = 2GM / c2). . So yes if you take a relatively small amount of mass and squeeze it small enough to become extremely dense then it would form a black hole.
When a massive particle is accelerated at very high speeds (LHC) there can be enough potential relative energy to mass to create micro black holes. Here is a link to explain in a little more detail. http://en.wikipedia.org/wiki/Micro_black_hole#Minimum_mass_of_a_black_hole

Lindon
2009-Oct-19, 10:44 PM
Well, cosmocrazy, and all you other intensely knowledgeable scientists out there, we gotta find out what happens to the stuff that goes into black holes. I came from a pioneering family -- they crossed the Oregon trail -- and I'm about 25% indian. But I'm frustrated because there isn't anymore wilderness -- unless I look up. But things just aren't moving fast enough -- we gotta figure out gravity and how to travel around the universe without having to worry about that speed of light limitation. And also, I say if it looks like a drain and acts like a drain -- then it must be a drain (i.e., black hole). I'll bet anything going into a black hole ends up getting ripped into the smallest particles possible and recycled back into ... ? What? Until you and your associates prove me right, everybody's going to keep calling me a crackpot! Thanks again -- it's all so interesting.

Durakken
2009-Oct-19, 10:46 PM
Well, cosmocrazy, and all you other intensely knowledgeable scientists out there, we gotta find out what happens to the stuff that goes into black holes. I came from a pioneering family -- they crossed the Oregon trail -- and I'm about 25% indian. But I'm frustrated because there isn't anymore wilderness -- unless I look up. But things just aren't moving fast enough -- we gotta figure out gravity and how to travel around the universe without having to worry about that speed of light limitation. And also, I say if it looks like a drain and acts like a drain -- then it must be a drain (i.e., black hole). I'll bet anything going into a black hole ends up getting ripped into the smallest particles possible and recycled back into ... ? What? Until you and your associates prove me right, everybody's going to keep calling me a crackpot! Thanks again -- it's all so interesting.

I'll let you go in first and test it out ^.^

cosmocrazy
2009-Oct-19, 10:49 PM
Well, cosmocrazy, and all you other intensely knowledgeable scientists out there, we gotta find out what happens to the stuff that goes into black holes. I came from a pioneering family -- they crossed the Oregon trail -- and I'm about 25% Indian. But I'm frustrated because there isn't anymore wilderness -- unless I look up. But things just aren't moving fast enough -- we gotta figure out gravity and how to travel around the universe without having to worry about that speed of light limitation. And also, I say if it looks like a drain and acts like a drain -- then it must be a drain (i.e., black hole). I'll bet anything going into a black hole ends up getting ripped into the smallest particles possible and recycled back into ... ? What? Until you and your associates prove me right, everybody's going to keep calling me a crackpot! Thanks again -- it's all so interesting.

It seems in a sense it already does, based on Hawking's radiation, crudely put, the information going into a BH is released back into the universe and the subsequent hole evaporates. http://en.wikipedia.org/wiki/Hawking_radiation

cosmocrazy
2009-Oct-19, 11:17 PM
Lindon, there's nothing crackpot about wanting to know things that remain unanswered. What is crackpot is claiming to "know" without any observational support to defend it.

stktos
2009-Oct-20, 01:20 AM
there's nothing crackpot about wanting to know things that remain unanswered.

So true! That is what makes science so fun!

Cougar
2009-Oct-20, 02:18 AM
It seems in a sense it already does, based on Hawking's radiation, crudely put, the information going into a BH is released back into the universe and the subsequent hole evaporates. http://en.wikipedia.org/wiki/Hawking_radiation

Ooh, I think you might get some argument about the information getting released. I don't know if that is a settled controversy. And while Hawking radiation seems to be held in fair regard, it is not yet something that has been observed or detected AFAIK.

Hornblower
2009-Oct-20, 02:21 AM
Lets say...
Size of the Planet = 1
Gravity of the Planet = 1
Density of the Planet = 1

If density goes up to 2
Size of planet must be reduced to 0 if gravity remains 1

If density goes down to 0
Size of planet must increase to 2 if gravity remains 1

If Size goes up to 2 and density remains at 1
Gravity must go up to 2

So, If we take a planet and decrease it's size to a marble through making it more dense the gravity will remain the same, however because we can get closer to the center of gravity it appears to be stronger.
You got two out of three wrong here. If we double the density, we reduce the radius to 1/2 to keep the same surface gravity. If we reduce the density to zero, we have no mass, and thus no gravity no matter how big we make it.

Seriously, a lot of people come here looking for good answers to basic physics questions. Please check your mathematical facts before posting.

Cougar
2009-Oct-20, 02:39 AM
And also, I say if it looks like a drain and acts like a drain -- then it must be a drain (i.e., black hole). I'll bet anything going into a black hole ends up getting ripped into the smallest particles possible and recycled back into ... ? What?

I don't know. You're the one betting. :)

Thing is, mass that falls into a black hole... stays there. It doesn't go anywhere. Its gravitational effect remains the same whether it's in a black hole or not in a black hole.

astromark
2009-Oct-20, 03:00 AM
'Lindon'., Its a good question and I see no record of it previously ;) Oh ya, its all interesting:) and you are amongst friends with your want to get us of this planet.
Unfortunately reality may prevent that ever happening. Unless we can break the rules we are stuck at less than c. I have 0 indication the rule can be broken.
You talk of space time fabric and how extreme velocity might punch through. Unfortunately that does not seem to be the case. Mass at high velocity can not get to c. ( that rule again ) What it can do is have kinetic energy held by its velocity or momentum. Remembering the other rule... That matter can not be created or destroyed. You can change is form. So your marble sized planet earth could have the mass of Earth and a substantial velocity. Some of that energy is going to be converted to heat if you stop it abruptly. but not ever a black holes worth. We simply do not have sufficient mass for that sort of energy. and has been noted. The mass of this Earth would not change regardless of its size.
Now,! that LHCollider and the sub atomic BH generation. Its not a given that it will actually do that. Its still a 'Work in Progress' and disappointing as it is. No seems to be that answer. Does a black hole exist for a plankt length of time.. ? If it can not be detected. Was it there ?
There's such an awful lot to yet be learned.":)"mark

mugaliens
2009-Oct-20, 05:21 AM
I had heard that scientists are theorizing (speculating) about the possibility that tiny particle-sized black holes might be created with the Large Hadron Collider once they get it up and running, and I had assumed that they were counting on the velocity of the impacting particles to precipitate the creation of the mini-black holes.

If this were even remotely possible, the BH that was created would radiate away (Hawking radiation) faster than our instruments could measure. It would be indistinguisheable from the release of relativistic kinetric energy of the impact had the BH not been created.

Durakken
2009-Oct-20, 05:29 AM
You got two out of three wrong here. If we double the density, we reduce the radius to 1/2 to keep the same surface gravity. If we reduce the density to zero, we have no mass, and thus no gravity no matter how big we make it.

Seriously, a lot of people come here looking for good answers to basic physics questions. Please check your mathematical facts before posting.

This was not meant to be mathematical at all. If it were I'd use the real numbers used in the math and actually go look for the formula.

I was illustrating the concept, not the math, and as I have pointed out numerous times, the concept is what should be talked about and leave the math out of it less asked because unless someone can grasp the basic concept the math really doesn't matter.

cosmocrazy
2009-Oct-20, 07:37 AM
Ooh, I think you might get some argument about the information getting released. I don't know if that is a settled controversy. And while Hawking radiation seems to be held in fair regard, it is not yet something that has been observed or detected AFAIK.

Yes I agree,

my wording was poor in the way I wanted to put it across.

I was basically pointing out that Lindon's thoughts about the mass/energy content or equal to, of the BH being dispersed back into the space/time of our universe had already been considered and that Hawking had come up with a theory to predict it.

JTankers
2009-Oct-20, 09:56 AM
...We all know that the spacetime fabric is flexible, and that it takes an extreme mass in an extremely condensed form to penetrate into the spacetime fabric...

Q: But didn't Einstein say something to the effect that acceleration and gravity are the same thing?
A: Yes, Einstein said exactly that (and he was very sober). Einstein taught that gravity warps spacetime in such a way that "stationary" in a gravity field is the same as accelerating towards gravity. For example, on Earth "stationary" is actually accelerating toward the center of Earth and 9.8 m/s^2. By standing on the surface of Earth, you are actually accelerating away from the center of Earth at 9.8 m/s^2. Exactly the same force you would feel if you were in a rocket ship in space (non-warped space time) accelerating at 9.8 m/s^s.

Q: The point I'm trying to make, and the question I'm trying to ask is, isn't it possible to replace mass with velocity to a certain extent to create a black hole?
A: You should be able to replace the spacetime warping effect of mass with acceleration (not velocity) away from an observer, so I think answer the answer would be velocity no, but acceleration yes.

Q: In other words, a solid object doesn't have enough mass to penetrate the spacetime fabric, but if that same item was accelerated fast enough, would it possibly be able to penetrate the spacetime fabric?
A: Sounds correct. However the term "penetrate the fabric of spacetime" seems to imply that the fabric of space time is broken. Modern re-evaluation of relativity theory applied to black hole physics indicate that physics does not 'break down' in black holes. Black holes approach but do not reach Infinite density and time stoppage and light is infinitely delayed from escaping. So the fabric of space time is perhaps "almost penetrated" by black holes (where time approaches a stop and density approaches but does not reach infinite density in finite time).

astromark
2009-Oct-20, 10:09 AM
Thats useful, thanks 'JTankers' 9.8 m/s^s = one g.
Have I got that right ?
A rate of acceleration being nine point eight metres per sec, per sec.

That aside I also wish to point out that there is no fabric of space time.
We start at the almost perfect vacuum of deep interstellar space and work your way up to the massive density of a Super Massive Black Hole. At every point between these two extremes is the state of matter as we understand it.
Millions of dollars and hundreds of man hours later the LHC might answer this question. Meantime we can speculate.
.

LotusExcelle
2009-Oct-20, 10:33 AM
</insertjoke>

<endjoke>

JTankers
2009-Oct-20, 12:25 PM
I also wish to point out that there is no fabric of space time.
.

Not fabric like you would make a suit out of perhaps... Nobel laureate Frank Wilzcek's book "The Lightness of Being, Mass Ether and the Unification of Forces" focuses on the requirement for ether (the grid, Higgs field, fabric of space-time, etc.).

On page 97 of his book Wilzcek writes:

The Mother of All Grids: Metric Field

Here's the Einstein quotation I saved up. In 1920 he worte,

"According to the general theory of relativity space without ether is unthinkable; for in such space there not only would be no propagation of light, but also no possibility of existence of standards of space and time (measuring-rods and clocks), nor therefore any space-time intervals in the physical sense."

astromark
2009-Oct-21, 07:26 AM
We know that in deepest space there are 'things'
Things like photons and Gama rays and x-rays and,,, lots and lots of stuff.
Some of it is massless and must be zipping along its path at c.
Space is not a medium. Sound is transmitted through a medium by vibrating the medium... Light and other sub atomic particles do not transmit as such. This talk of ether is largely a misunderstanding of the void space. I am understanding that empty space is not empty... with some hydrogen atoms floating about and even a particle of real matter every so often. As for the Higgs. While all those other energies zoom on through. Photon streams and gravity are at home in this matter less space. Show me evidence of this ether ? Dark energy ? and even Dark matter... there's a great deal yet to learn. Metric Field must be some way of measuring a medow... its got little to do with astronomy. If you look again at what Einstein said. No fabric. Not a thing that we know of. Apparently almost a perfect void. We have reasons enough to consider Dark matter as real. We can detect its mass. We can postulate Dark Energy as its driving the acceleration rate. But please do not add ether... without showing me why.

.

Lindon
2009-Oct-21, 02:28 PM
Wouldn't "ether" and "quantum foam" perhaps be the same thing?

JTankers
2009-Oct-22, 02:58 AM
If you look again at what Einstein said. No fabric. But please do not add ether... without showing me why.

.

Why ether? Isaac Newton's spinning spheres (or similar spinning buckets) in space argument, certainly. Without a force to define "absolute rotational rest" (rotation is not relative, there is absolute rotational rest in space), then Isaac Newton's rotating sphere's argument would not make sense.[1] Dr. Einstien was fascinated by that argument and again in 1920 Einstien clearly wrote: "According to the general theory of relativity space without ether is unthinkable;.."

(And Lindon, Quantum foam I think tends to refer to virtual particles that zip in and out of existence, probably just a component of the [very mysterious] ether I would think.)

[1] Isaac Newton's rotating spheres argument http://en.wikipedia.org/wiki/Rotating_spheres

mugaliens
2009-Oct-22, 08:40 AM
Not possible (http://www.bautforum.com/space-astronomy-questions-answers/95180-creating-ones-own-black-hole-how.html#post1602964), folks.

astromark
2009-Oct-22, 09:26 AM
So we are talking in circles. I still reject ether. Yes one of the properties of interstellar space might be that sub atomic particles seem to appear and disappear at will. I know of things as yet not well explained and, things that are just plainly wrong. Its finding the explanations that drives the want to learn. I am fussy. I choose what facts are excepted and what are not. If you expect me to understand ether tell me how you now of it ? buy what method has it been observed ? Is there a need for it with no proof. Do I group it with Dark Energy ?
.

Lindon
2009-Oct-22, 03:46 PM
Stand back and watch this amazing display of "logic" from a non-scientific mind:

So, we go into deep space vaccum with the jar that we used to catch bees in when we were a kid. We stick our jar out of the space ship and "capture" a jar full of the nothingness. We bring it back to our science lab and run some experiments. We observe that within that jar of nothing, there are virtual particles popping into and out of existence. Doesn't that lend credence to the assumption that what we really have in our jar is not "nothing", but "something", and that the something could be considered by some as a jar full of ether?

Durakken
2009-Oct-22, 05:17 PM
Ether and Quantum Foam are not the same thing...

Ether has been disproven several times over.

Lindon
2009-Oct-22, 09:37 PM
Ether and Quantum Foam are not the same thing...

Ether has been disproven several times over.

Got it, and I'll never make that connection again. I just read (most of) Einstein's speech in 1920 dealing with "Ether and the Theory of Relativity", and while I'd have to read it again "a few" more times to fully grasp it, I think I can see what Einstein's idea of "ether" is/was, and why it's definitely not Quantum Foam. But what interests me so much about the concept is the apparant fact that even where there is what we would call a complete vacuum -- nothing! -- there is in fact physical activity taking place at that point which science just doesn't understand. In fact, if we could pick a 1-light-year cube of "nothing" in space, then place a super-massive object in the middle of that cube, we would if nothing else get a bending of space-time. So, space-time is everywhere it seems -- in space, under my nose, in my wife's purse, everywhere. And wherever there is "nothing" except whatever it is that space-time consists of, we've got quantum foam. Are they perhaps one in the same? Do we even know what space-time consists of -- electromagnetic waves maybe, or just pure magic?? Thanks in advance to whoever helps me understand this concept a little better.

01101001
2009-Oct-23, 12:31 AM
And wherever there is "nothing" except whatever it is that space-time consists of, we've got quantum foam.

You speak as if quantum foam is not to be found where there is something. Do you mean to?

Durakken
2009-Oct-23, 01:34 AM
Also... Just because Einstein said something doesn't make it true. That's called an argument from authority and it is a logical fallacy.

Ether is a word that refers to an interstellar medium... something like solar winds mixed with dark matter. The idea is that it was made of some sort of particles like a photon.

Quantum Foam is more based on the idea that at super small scales particles can pop in and out of existence which creates a foam of sorts and this happens everywhere at all times...

The ideas are similar on the surface but the ether is more about a permanent particle stream that is coming from some where magical

mugaliens
2009-Oct-23, 03:52 AM
I view space-time as more of the relativistic relationship between energies and masses than anything "ethereal" in and of itself, for it those energies and masses did not exist, space-time would be largely meaningless.

DrWho
2009-Oct-23, 04:01 AM
Ether is a word that refers to an interstellar medium... something like solar winds mixed with dark matter.
Nope. Ether is a word that refers to a class of organic compounds that contain an ether group (an oxygen atom connected to two alkyl or aryl groups). :)

cosmocrazy
2009-Oct-23, 09:40 AM
I view space-time as more of the relativistic relationship between energies and masses than anything "ethereal" in and of itself, for it those energies and masses did not exist, space-time would be largely meaningless.

I tend to agree with you on this, but i'm not sure how expansion of space-time is explained at the large distances away where it is close to and maybe superluminal.

Lindon
2009-Oct-23, 02:50 PM
You speak as if quantum foam is not to be found where there is something. Do you mean to?

Yes, that's what I meant, but only because I did not realize that quantum foam has been observed where there is "something", if that's the point you're making. I understand that on the atomic level, no atom or particle can be "tracked" and that they are apparantly popping into and out of existence continually, and that every clump of matter in the universe is comprised of these "now you see it now you don't" atoms/particles. Is that the same thing as quantum foam? Hey, with each dumb question, I learn a little more. Thanks guys (and gals if that fits)!

mugaliens
2009-Oct-23, 10:16 PM
Is that the same thing as quantum foam?

Lindon - suppose you read this (http://en.wikipedia.org/wiki/Quantum_foam), then you should be able to answer your own question.

Lindon
2009-Oct-23, 10:31 PM
Thanks for that link mugaliens. Actually, I HAD read that before and not long ago. In fact, it was after my last post and the response provided by 01101001 that I did the Google search and found that article. From it, I get that quantum foam definitely is not Einstein's "ether". I thought I had it all figured out, then 01101001 threw me the curveball. So which is it: quantum foam is only in "the void" as described by Wikipedia, or it could also be "where there is something" as roundabout suggested by 01101001 in his question to me?

mugaliens
2009-Oct-24, 06:09 AM
Thanks for that link mugaliens. Actually, I HAD read that before and not long ago. In fact, it was after my last post and the response provided by 01101001 that I did the Google search and found that article. From it, I get that quantum foam definitely is not Einstein's "ether". I thought I had it all figured out, then 01101001 threw me the curveball. So which is it: quantum foam is only in "the void" as described by Wikipedia, or it could also be "where there is something" as roundabout suggested by 01101001 in his question to me?

I'm sure Ken G will step in if I get this wrong, but from what I understand, it's everywhere, whether in the interstellar reaches, at the event horizons of BH's, or in your elbow.

Lindon
2009-Nov-19, 09:13 PM
Here's a recent article on universetoday.com that specifically describes how we might create a black hole.

Black Hole Drive Could Power Future Starships

http://www.universetoday.com/2009/11/19/black-hole-drive-could-power-future-starships/

There an ArXiv paper on it.

Is this realistic?

korjik
2009-Nov-19, 09:26 PM
I wouldnt make a synthetic black hole. They really suck.

:)

coreybv
2009-Nov-19, 10:00 PM
and that the something could be considered by some as a jar full of ether?

No, you have a jar full of space.