<p>You can't make a black hole simply by accelerating a particle, but it has been theorized that smashing some together with ridiculously high energies could produce micro black holes. This, as far as I know, has never been known to happen at particle accelerators, simply because they are not powerful enough. </p>

CC BY-SA 4.0
2020-05-05T19:05:54.757Z
2020-05-05T19:05:54.757Z
Mr.555
<p>Relativistic mass increase is inertial, not gravitational, so no, you couldn't make a black hole by accelerating a particle. What happens is that the more energy you use to accelerate the particle, the more its inertial mass increases, but the more its inertial mass increases, the harder it is to accelerate. There comes a point near the speed of light when virtually all the energy you pump into the system is manifested as mass increase rather than velocity, and you can't make the particle go any faster. The best idea, if you want a really fast particle with huge amounts of energy, much more than could be produced by an accelerator, is to use a cosmic ray. Cosmic rays are fast protons or atomic nuclei which have been accelerated by natural events such as supernova explosions to much higher energies than you could get in an accelerator. </p>

<p>Cosmic rays have been used for particle experiments, but the snag is that they are random events, so you don't know exactly where to put your particle detectors to intercept the best ones. To give you an idea of how great their energies can sometimes be, the most powerful cosmic ray particles have the kinetic energy of a rifle bullet, yet the atomic nucleus which carries this energy is so minute that it cannot be seen in even the most powerful electron microscope!</p>

CC BY-SA 4.0
2019-07-09T00:02:09.230Z
I thought we had no way to tell inertial mass and gravitational mass apart?
https://www.physlink.com/Education/AskExperts/ae305.cfm
Ryan_L
CC BY-SA 4.0
2019-07-09T07:44:07.027Z
*"There comes a point near the speed of light when virtually all the energy you pump into the system is manifested as mass increase rather than velocity, and you can't make the particle go any faster."* That's not quite correct. There is no point where velocity increase stops. As you accelerate an ultra-relativistic body, its velocity, momentum, and kinetic energy continue to increase; the velocity increases asymptotically towards *c*, the momentum & KE increase without bounds.
PM 2Ring
CC BY-SA 4.0
2019-07-08T21:50:18.357Z
2019-07-08T21:50:18.357Z
Michael Walsby
<p>Imagine you have a particle accelerator that you can crank up to arbitrarily high energies.  Because of General Relativity, the particles get heavier and heavier as you dump more energy into them.  Will these particles ever become a black hole from this relativistic mass?  If so, what will an observer particle moving parallel to the black hole, just below that speed, see?  What I'm getting at is, kinetic energy is relative.  So therefore relativistic mass is as well.  So would these particles be black holes to some observers but not others?</p>

CC BY-SA 4.0
2019-07-08T19:52:06.507Z
Might get better quality answers in Physics.SE
tuomas
CC BY-SA 4.0
2019-07-08T20:09:45.147Z
https://physics.stackexchange.com/questions/3436/if-a-mass-moves-close-to-the-speed-of-light-does-it-turn-into-a-black-hole seems like a place where you might find an answer, although I didn't find any of the answers quite as clear as I'd like
Steve Linton
CC BY-SA 4.0
2019-07-09T07:22:31.820Z
Relativistic mass is a deprecated concept because it can be misleading and confusing. This is one of those situations where it's misleading. ;) Please see https://physics.stackexchange.com/questions/133376/why-is-there-a-controversy-on-whether-mass-increases-with-speed
PM 2Ring
CC BY-SA 4.0
2019-07-09T07:37:54.113Z
However, if you collide a pair of objects with insanely high relative kinetic energy, then you *could* create a black hole. "All" you need to do is to make sure you have enough energy in a small enough radius.
PM 2Ring
CC BY-SA 4.0
2019-07-09T17:07:41.737Z
@PM2Ring  ... and keep the energy contained for some length of time.  I have no idea what sort of containment would be needed, seeing as, in the rest frame of one of the particles, that particle is nearly massless and the other is absurdly massive. I suspect the "other" particle would have to be a black hole all by itself.
Carl Witthoft
CC BY-SA 4.0
2019-07-09T17:27:08.337Z
@Carl For example, a black hole of radius 1 fermi (about the size of a proton) has a mass a little over 673 million metric tons. So if you get *all* the energy obtained by annihilating 337 million tons of antimatter with an equal amount of normal matter and somehow convert that into the KE of a pair of protons in a head-on collision, then when the protons collide you'll have all that energy within the required Schwarzschild radius. I think. ;) The protons may radiate some of that energy away before they collide.
PM 2Ring
CC BY-SA 4.0
2019-07-09T17:33:02.623Z
I'm not claiming that this process is in any way practical, I just wanted to make tangible just how high the energy requirements are. It's hard enough just making micrograms of antimatter, let alone hundreds of millions of tons of the stuff. And when antimatter & matter collide the energy is released ultimately) as high energy gamma rays (some intermediate products like pions may also be formed), and we don't know how to efficiently capture that energy & convert it into useful directed kinetic energy.
PM 2Ring
<black-hole><general-relativity>
Can you create a black hole using kinetic energy?
Ryan_L
# Can you create a black hole using kinetic energy?

(Asked by: username_0 on 2019-07-08)

Imagine you have a particle accelerator that you can crank up to arbitrarily high energies. Because of General Relativity, the particles get heavier and heavier as you dump more energy into them. Will these particles ever become a black hole from this relativistic mass? If so, what will an observer particle moving parallel to the black hole, just below that speed, see? What I'm getting at is, kinetic energy is relative. So therefore relativistic mass is as well. So would these particles be black holes to some observers but not others?

**Tags:** black-hole, general-relativity
> **Comments:**
> **username_1**: Might get better quality answers in Physics.SE  
> **username_2**: https://physics.stackexchange.com/questions/3436/if-a-mass-moves-close-to-the-speed-of-light-does-it-turn-into-a-black-hole seems like a place where you might find an answer, although I didn't find any of the answers quite as clear as I'd like  
> **username_3**: Relativistic mass is a deprecated concept because it can be misleading and confusing. This is one of those situations where it's misleading. ;) Please see https://physics.stackexchange.com/questions/133376/why-is-there-a-controversy-on-whether-mass-increases-with-speed  
> **username_3**: However, if you collide a pair of objects with insanely high relative kinetic energy, then you *could* create a black hole. "All" you need to do is to make sure you have enough energy in a small enough radius.  
> **username_4**: @PM2Ring  ... and keep the energy contained for some length of time.  I have no idea what sort of containment would be needed, seeing as, in the rest frame of one of the particles, that particle is nearly massless and the other is absurdly massive. I suspect the "other" particle would have to be a black hole all by itself.  
> **username_3**: @Carl For example, a black hole of radius 1 fermi (about the size of a proton) has a mass a little over 673 million metric tons. So if you get *all* the energy obtained by annihilating 337 million tons of antimatter with an equal amount of normal matter and somehow convert that into the KE of a pair of protons in a head-on collision, then when the protons collide you'll have all that energy within the required Schwarzschild radius. I think. ;) The protons may radiate some of that energy away before they collide.  
> **username_3**: I'm not claiming that this process is in any way practical, I just wanted to make tangible just how high the energy requirements are. It's hard enough just making micrograms of antimatter, let alone hundreds of millions of tons of the stuff. And when antimatter & matter collide the energy is released ultimately) as high energy gamma rays (some intermediate products like pions may also be formed), and we don't know how to efficiently capture that energy & convert it into useful directed kinetic energy.  

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## 2 answers

### Answer by username_5 on 2020-05-05. Score: 1

You can't make a black hole simply by accelerating a particle, but it has been theorized that smashing some together with ridiculously high energies could produce micro black holes. This, as far as I know, has never been known to happen at particle accelerators, simply because they are not powerful enough.


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### Answer by username_6 on 2019-07-08. Score: -4

Relativistic mass increase is inertial, not gravitational, so no, you couldn't make a black hole by accelerating a particle. What happens is that the more energy you use to accelerate the particle, the more its inertial mass increases, but the more its inertial mass increases, the harder it is to accelerate. There comes a point near the speed of light when virtually all the energy you pump into the system is manifested as mass increase rather than velocity, and you can't make the particle go any faster. The best idea, if you want a really fast particle with huge amounts of energy, much more than could be produced by an accelerator, is to use a cosmic ray. Cosmic rays are fast protons or atomic nuclei which have been accelerated by natural events such as supernova explosions to much higher energies than you could get in an accelerator.

Cosmic rays have been used for particle experiments, but the snag is that they are random events, so you don't know exactly where to put your particle detectors to intercept the best ones. To give you an idea of how great their energies can sometimes be, the most powerful cosmic ray particles have the kinetic energy of a rifle bullet, yet the atomic nucleus which carries this energy is so minute that it cannot be seen in even the most powerful electron microscope!

> **Comments:**
> **username_0**: I thought we had no way to tell inertial mass and gravitational mass apart? https://www.physlink.com/Education/AskExperts/ae305.cfm  
> **username_3**: *"There comes a point near the speed of light when virtually all the energy you pump into the system is manifested as mass increase rather than velocity, and you can't make the particle go any faster."* That's not quite correct. There is no point where velocity increase stops. As you accelerate an ultra-relativistic body, its velocity, momentum, and kinetic energy continue to increase; the velocity increases asymptotically towards *c*, the momentum & KE increase without bounds.  

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