# How much energy to tear apart a black hole? **URL:** \ **Category:** Factual Questions\ **Created:** [November 14, 2002, 12:44am UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655 "2002-11-14T00:44:24Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![SPOOFE](https://avatars.discourse-cdn.com/v4/letter/s/c5a1d2/32.png) [@SPOOFE](https://boards.straightdope.com/u/SPOOFE)\ **Post date:** [November 14, 2002, 12:44am UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/1 "2002-11-14T00:44:24Z")
I’m sitting here, reading up on cosmic phenomena and degenerate matter and all that yippy-fun stuff, and the thought randomly occurred to me… how would one go about deconstructing a black hole? I’m assuming that it is possible, just requiring a crapload of energy and super-exotic technology (like ultra-powerful tractor beams or some other Star Trek type stuff). So would it be possible to do this? I’m sure it’s not _probable_ and all, but what about possible? Obviously, one would need some method of circumventing the whole “not even light can escape” thing. I guess what I’m asking is how much energy would you need to overcome the gravitational binding energy of the black hole’s singularity? Or is there just some odd tidbit of info that I’m missing? ---
**Author:** ![Alien2022](https://avatars.discourse-cdn.com/v4/letter/a/e19adc/32.png) [@Alien2022](https://boards.straightdope.com/u/Alien2022)\ **Post date:** [November 14, 2002, 1:00am UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/2 "2002-11-14T01:00:54Z")
I’m just guessing, but maybe creating a donut type gravity well around the blackhole, with it in the middle. Then intensify the strength of the donut grav well so that it’s stronger than the original blackhole… If the gravity reaches the same strenght at the same time, it might tear it apart, but what happens then? Do you then create a super black hole? Too many possibilities. Do you tear a rift in space/time? Do you create a wormhole? ---
**Author:** ![Fang](https://avatars.discourse-cdn.com/v4/letter/f/96bed5/32.png) [@Fang](https://boards.straightdope.com/u/Fang)\ **Post date:** [November 14, 2002, 1:02am UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/3 "2002-11-14T01:02:51Z")
> [@](#): > > \*Originally posted by Alien2022 \* > **I’m just guessing, but maybe creating a donut type gravity well around the blackhole, with it in the middle.** “I find your theory of a donut-shaped universe intriguing.” - Stephen Hawking to Homer Simpson ---
**Author:** ![Omphaloskeptic](https://avatars.discourse-cdn.com/v4/letter/o/bcef8e/32.png) [@Omphaloskeptic](https://boards.straightdope.com/u/Omphaloskeptic)\ **Post date:** [November 14, 2002, 2:58am UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/4 "2002-11-14T02:58:47Z")
> [@](#): > > \*Originally posted by SPOOFE \* > **I’m sitting here, reading up on cosmic phenomena and degenerate matter and all that yippy-fun stuff, and the thought randomly occurred to me… how would one go about deconstructing a black hole?** Step 1: Get it really cold. Step 2: Wait a really long time. ---
**Author:** ![Enola\_Straight](https://avatars.discourse-cdn.com/v4/letter/e/dec6dc/32.png) [@Enola\_Straight](https://boards.straightdope.com/u/Enola_Straight)\ **Post date:** [November 14, 2002, 5:24am UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/5 "2002-11-14T05:24:28Z")
How about throwing some anti-mass at it? Not anti-matter, anti-MASS. Something that would neutralize the mass of the black hole. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [November 14, 2002, 5:59am UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/6 "2002-11-14T05:59:51Z")
Except there’s no such thing as anti-mass. At least, none has been discovered. To escape from a black hole you have to travel faster than light. It’s as difficult to do there as anywhere else, meaning it requires an infinite amount of energy. The only way to destroy a black hole is, as **Omphaloskeptic** said, to make nothing falls into it and wait a _really_ long time. The so-called Hawking radiation will gradually carry away mass. ---
**Author:** ![Mirage](https://avatars.discourse-cdn.com/v4/letter/m/eb9ed0/32.png) [@Mirage](https://boards.straightdope.com/u/Mirage)\ **Post date:** [November 14, 2002, 6:07am UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/7 "2002-11-14T06:07:20Z")
What do you mean “rip it apart”? You cannot pull the black hole in two because there is nothing to split. The singularity is infinately small and you can’t take half of that. Black holes loose mass to Hawking radiation, so I guess the best that you can hope for is to find some way to suck more out and convert it to another black hole. But regardless, the common concept of breaking something in half does not apply to this situation. ---
**Author:** ![DarrenS](https://avatars.discourse-cdn.com/v4/letter/d/977dab/32.png) [@DarrenS](https://boards.straightdope.com/u/DarrenS)\ **Post date:** [November 14, 2002, 6:40am UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/8 "2002-11-14T06:40:12Z")
How sure are we that the singularity is a dimensionless point, with no internal structure? I was wondering this while reading the thread I opened on neutron stars. Are there any reputable hypotheses about what the “matter” constituting the singularity might be like? Or do we just see the equations, say to ourselves, “I guess the singularity is where nature divided by zero”, and conclude we can’t know anything about it? ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [November 14, 2002, 7:33am UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/9 "2002-11-14T07:33:03Z")
> [@](#): > > \*Originally posted by DarrenS \* > **How sure are we that the singularity is a dimensionless point, with no internal structure?** That’s pretty much the definition of a singularity. If you are asking if black holes are really singularities, the quick answer is that if it isn’t a singularity, then some force must be counteracting the gravitational force and preventing collapse. Right now we think there is no such force in the universe, but of course we could be wrong. ---
**Author:** ![SPOOFE](https://avatars.discourse-cdn.com/v4/letter/s/c5a1d2/32.png) [@SPOOFE](https://boards.straightdope.com/u/SPOOFE)\ **Post date:** [November 14, 2002, 11:11am UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/10 "2002-11-14T11:11:33Z")
> [@](#): > > What do you mean “rip it apart”? Artificially extract mass from the black hole, essentially. Aside from the whole “insane amounts of gravity” problem (a trifling matter, really), is there any physical phenomenon that would prevent this? ---
**Author:** ![JS\_Princeton](https://avatars.discourse-cdn.com/v4/letter/j/57b2e6/32.png) [@JS\_Princeton](https://boards.straightdope.com/u/JS_Princeton)\ **Post date:** [November 14, 2002, 4:23pm UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/11 "2002-11-14T16:23:52Z")
Yes, SPOOFE, there is a physical phenomenon preventing this. Nothing can leave the event horizon of a black hole. Not one thing, not know how. Even if you got the mass extractor to move at the speed of light, it would never leave. Therefore you are not allowed to take mass away, only add mass. The only hypothesized mechanism for taking mass away from a black hole is Hawking Radiation, and this is an unobserved phenomenon. I’m afraid you are asking about the impossible. ---
**Author:** ![Captain\_Amazing](https://avatars.discourse-cdn.com/v4/letter/c/6de8d8/32.png) [@Captain\_Amazing](https://boards.straightdope.com/u/Captain_Amazing)\ **Post date:** [November 14, 2002, 5:51pm UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/12 "2002-11-14T17:51:39Z")
> [@](#): > > \*Originally posted by SPOOFE \* > \*\*and the thought randomly occurred to me… how would one go about deconstructing a black hole? \*\* Well, first you need to admit to yourself that your use of the term “black hole” is influenced by your biases… \ ---
**Author:** ![Shodan](https://avatars.discourse-cdn.com/v4/letter/s/9f8e36/32.png) [@Shodan](https://boards.straightdope.com/u/Shodan)\ **Post date:** [November 14, 2002, 6:13pm UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/13 "2002-11-14T18:13:16Z")
**Captain Amazing** - Only on the SDMB do you get jokes which combine physics with literary criticism. And an audience who appreciates them. Thanks for the chortle. Regards, Shodan ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [November 14, 2002, 7:40pm UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/14 "2002-11-14T19:40:26Z")
The only way to get matter out of a black hole is to wait for the Hawking radiation. For a stellar-mass hole, it takes about 10[sup]67[/sup] years to evaporate completely, even if it’s not accreting at all. In the present Universe, though, even just the accretion of photons from the Cosmic Microwave Background is more than enough (by a factor of over a million) to keep the hole well-fed. Hence **Omphaloskeptic** ’s comments to “get it really cold and wait a long time”. Now, if the hole has a significant charge (not likely) or angular momentum (significantly more likely), then you can extract some of the energy (that part asssociated with the electric field or angular momentum) by throwing things into the hole just right: This is called the Penrose process. The limit of how much you can get out this way is a good deal smaller than the total mass of the hole, and you need to throw in a comparable amount of mass to get it, but there’s still a lot of energy available there, by terrestrial standards. Note that this process still continually increases the size of the black hole, in some sense (specifically, it increases the area of the event horizon), so it’s not exactly deconstructing the hole. The closest thing I can think of to what you want to do, is it _might_ be possible, under extreme circumstances, to split a black hole into two smaller holes. When two black holes merge, they emit truly ludicrous amounts of energy in the form of gravitational waves, in a very characteristic pattern. By “ludicrous”, I mean far more energy than the largest stars can emit over an entire lifetime. Well, if you could produce that same pattern of extremely energetic gravitational waves, but travelling inward rather than outward, you _might_ be able to reverse the process, and split the hole in two. But don’t underestimate this: The only way I know of to even possibly have a chance of getting gravtitational waves that powerful, travelling inward to the hole, is for them to be present when the Universe was created in the first place. So there you go: Just re-create the Universe, and you can split a black hole ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [November 14, 2002, 8:08pm UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/15 "2002-11-14T20:08:58Z")
some bh’s have a ring instead of a point mass in the center - caused by rotation of the BH. (this assumes we are going with BH’s as fact and not assuming that they might be things like lost socks or gravastars). If you cound add rotational energy to it you may be able to spin it apart - or at least enlarge the ring bigger then the event horizon. Another thing you could do is analiate it with a white hole but they are harder to find then black hloes and most likely not portable. Also even if a BH evaporates away doesn’t it still have the gravity well even when all matter has evaporated - i remember seeing something like this somewhere? ---
**Author:** ![Whack-a-Mole](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whack-a-mole/32/141_2.png) [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)\ **Post date:** [November 14, 2002, 8:19pm UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/16 "2002-11-14T20:19:52Z")
Ok…earlier it was said that there is no such thing as _anti-mass_ which is what I thought too. Anti-matter does indeed have mass and merely throwing anti-matter into a black hole will get you nothing but a bigger black hole. So how is Hawking Radiation doing its bit to shrink the black hole. I thought a particle and anti-particle pair were created and the anti-particle may fall into the event horizon while the othr particle flies away. If the Hawking anti-particle isn’t anti-mass and we’ve determined anti-matter won’t do it how is the Hawking Radiation doing its trick to shrink the black hole? ---
**Author:** ![Sacroiliac](https://avatars.discourse-cdn.com/v4/letter/s/ecb155/32.png) [@Sacroiliac](https://boards.straightdope.com/u/Sacroiliac)\ **Post date:** [November 14, 2002, 9:31pm UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/17 "2002-11-14T21:31:19Z")
> [@](#): > > If the Hawking anti-particle isn’t anti-mass and we’ve determined anti-matter won’t do it how is the Hawking Radiation doing its trick to shrink the black hole? The hole expended enough energy to create two real particles but only got the energy of one them back. ---
**Author:** ![Ring](https://avatars.discourse-cdn.com/v4/letter/r/6a8cbe/32.png) [@Ring](https://boards.straightdope.com/u/Ring)\ **Post date:** [November 14, 2002, 9:58pm UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/18 "2002-11-14T21:58:36Z")
Damn it, I knew this would happen. The above post was not by Sacroiliac it was by Ring. ---
**Author:** ![SPOOFE](https://avatars.discourse-cdn.com/v4/letter/s/c5a1d2/32.png) [@SPOOFE](https://boards.straightdope.com/u/SPOOFE)\ **Post date:** [November 14, 2002, 11:42pm UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/19 "2002-11-14T23:42:08Z")
> [@](#): > > I’m afraid you are asking about the impossible. Well, yeah… those’re the best questions to ask. 😃 ---
**Author:** ![nth](https://avatars.discourse-cdn.com/v4/letter/n/58956e/32.png) [@nth](https://boards.straightdope.com/u/nth)\ **Post date:** [November 14, 2002, 11:43pm UTC](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655/20 "2002-11-14T23:43:26Z")
i thought anti-matter when it meets matter, it will cancel each other out? [Next page](https://boards.straightdope.com/t/how-much-energy-to-tear-apart-a-black-hole/136655.md?page=2)