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Marc Asturias
Oct11-06, 02:52 PM
So a quick question from a novice...

I understand that scientists are now able to or are on the verge of
creating black holes of short-duration using a particle accelerator.
Whether or not this is true, let's play with the idea for a second.

I also understand that scientists using what I believe was called a
proton decelerator, were able to capture antimatter. I believe this
was at CERN.

My question is simple, could small black holes be grown by feeding
them matter after creation and annihilating them or controlling them
through the use of antimatter? Are the projects linked somehow? Can a
singularity be controlled in this fashion?


Sincerely,


Marc J.Asturias
Producer and Host
wizardsoftechnology.com
The Wizards of Technology Radio Show
Wizards of Technology Broadcast Network

[Mod. note: HTML fragment snipped. Please post in ASCII only. -ik]

Baugh
Oct11-06, 02:52 PM
Marc Asturias wrote:
> So a quick question from a novice...
>
> I understand that scientists are now able to or are on the verge of
> creating black holes of short-duration using a particle accelerator.
> Whether or not this is true, let's play with the idea for a second.

No you misunderstand. In order to acheive that scale you'd have
to build astronomically large particle colliders.

> I also understand that scientists using what I believe was called a
> proton decelerator, were able to capture antimatter. I believe this was
> at CERN.
>
> My question is simple, could small black holes be grown by feeding them
> matter after creation and annihilating them or controlling them through
> the use of antimatter? Are the projects linked somehow? Can a
> singularity be controlled in this fashion?

Yes in principle if it is of sufficient size that it won't evaporate
before you are able to hit it with some particles. But that sufficient
size will be quite large as compared to atomic or molecular masses.
On the order of tons if I'm not mistaken...let's see:

According to Hawking's theory black holes have a temperature:
kT = hbar c^3/(8 pi GM) [ergs]
Radius:
R = 2GM/c^2 [cm]
and thus a surface area:
A = 16 pi G^2 M^2/c^4 [cm^2]

Radiating as a black body the rate of energy loss will be
given by the Stefann-Boltzmann equation:
dE/dt = - sigma T^4 * A
where \sigma is (pi^2 k^4)/(60 hbar^3c^2).[erg/cm^2 s K^4]


Noting that dM/dt = dE/c^2dt gives: ... working it out on paper...

M^2 dM/dt = - (hbar c^4)/(15360 pi G^2) ~ 4x10^24 g^3/s

Integrating yields
M^2dM = const dt
t = M^3/3*const = M^3 [s/g^3]

So if I have not made any gross mathematical errors (quite
possible at this hour...) then for a black hole to last one
second then its mass must weigh M = 2.2x10^8 grams
( or 220000kg, or 220 metric tons.)
Dividing by 10 in the mass then means we divide by 10^3 in
the time.

22 metric tones will last only 1 millisecond.
2.2 metric tones will last only 1 microsec.
220kg will last only 1 nano-second
(the time it takes light to travel one foot)

22kg will last only one pico second. (.3 mm)
2.2 kg will last onnly one femtosecond (.3 micrometers)
(infrared wavelengths)
220 g will last only one attosecond, ( .3nanometers)
(wavelengths of hard x-rays or gamma rays)
22 g -> 1 zeptosecond = (.3 picometers)
(the Bohr radius of H atoms is 53 picometers)
2.2 g -> 1 yoctosecond -> . 0.3 femtometer
(this gets us down to subnuclear scale)

Note these length scales are not BH radii. A 2.2 gram black hole
will have a radius of (2.2)*2G/c^2 = 3.3x10^-28 cm = 3.3x10^-15
femtometers. That is to say the scale of a nucleus is to us
as the scale of a 1 gram black hole is to a nucleus. Very Tiny!

Now consider also that these grams of mass will convert directly
to energy as the black hole evaporates (explodes on these time-scales).
No different from an anti-matter explosion and much more powerful
than mere nuclear weapons. 1 kiloton TNT = 4x10^19 ergs =
0.02 grams total conversion to energy.

So as you see, according to this scale of things, it is improbable
that scientists are close to concentrating the force of a nuclear
blast into a ball smaller than an atomic nucleus by the same
ratio that a nucleus is smaller than the height of a young man.

But playing with these numbers is fun...

Lets go the other way. A black hole the mass of the Earth
(6x10^27g = 3x20x10^20 metric tons)
will last: 27x10^60 seconds or 9x10^54 years.

Let's try to figure the mass of a room temperature (80F~300K)
black hole:

kT =k*300K = 4.14x10^-16[ergs] = hbar c^3/(8 pi GM) [ergs]
M = hbar c^3 / 4.14x10^-16 G [grams]
= 1x10^27 grams = 1/6 the mass of the earth.

That one sounds familiar to me.

Regards,
James Baugh

FrediFizzx
Oct11-06, 02:53 PM
"Marc Asturias" <mistermarc@wizardsoftechnology.com> wrote in message
news:2F68D806-4AF1-4212-9D37-E58E76BE0BB6@wizardsoftechnology.com...
| So a quick question from a novice...
|
| I understand that scientists are now able to or are on the verge of
| creating black holes of short-duration using a particle accelerator.
| Whether or not this is true, let's play with the idea for a second.

Is this in reference to the May issue Scientific American article about
"Quantum Black Holes"? If not, you should read that article. You can
also read Steven B. Giddings eprint "Black Holes at Accelerators" at the
following link.

http://arxiv.org/abs/hep-th/0205027

| I also understand that scientists using what I believe was called a
| proton decelerator, were able to capture antimatter. I believe this
| was at CERN.
|
| My question is simple, could small black holes be grown by feeding
| them matter after creation and annihilating them or controlling them
| through the use of antimatter? Are the projects linked somehow? Can a
| singularity be controlled in this fashion?

I don't think mini black holes would be stable enough to do this
provided they could even be made in the first place. IOW, they would
decay faster than you would be able to "feed" them. ;-)

FrediFizzx

http://www.vacuum-physics.com/QVC/quantum_vacuum_charge.pdf
or postscript
http://www.vacuum-physics.com/QVC/quantum_vacuum_charge.ps

Dirk Bruere at Neopax
Oct11-06, 02:53 PM
FrediFizzx wrote:

> I don't think mini black holes would be stable enough to do this
> provided they could even be made in the first place. IOW, they would
> decay faster than you would be able to "feed" them. ;-)
>
> FrediFizzx
>
> http://www.vacuum-physics.com/QVC/quantum_vacuum_charge.pdf
> or postscript
> http://www.vacuum-physics.com/QVC/quantum_vacuum_charge.ps

Am I correct in assuming that if one uses 100% matter to create a mini BH, when
it evapourates 50% of the emitted matter is antimatter?

--
Dirk

The Consensus:-
The political party for the new millenium
http://www.theconsensus.org

FrediFizzx
Oct11-06, 02:53 PM
"Dirk Bruere at Neopax" <dirk@neopax.com> wrote in message
news:3eqdufF4dfvhU3@individual.net...
| FrediFizzx wrote:
|
| > I don't think mini black holes would be stable enough to do this
| > provided they could even be made in the first place. IOW, they
would
| > decay faster than you would be able to "feed" them. ;-)

| Am I correct in assuming that if one uses 100% matter to create a mini
BH, when
| it evapourates 50% of the emitted matter is antimatter?

The eprint article that I provided the link to didn't specifically say
but since accelerator collisions do produce anti-matter I suppose its
decay might be 50-50. I am sure some of the references in the eprint
have more theoretical info if one wishes to research it.

FrediFizzx

http://www.vacuum-physics.com/QVC/quantum_vacuum_charge.pdf
or postscript
http://www.vacuum-physics.com/QVC/quantum_vacuum_charge.ps

Frank Hellmann
Oct11-06, 02:53 PM
Marc Asturias wrote:
> My question is simple, could small black holes be grown by feeding
> them matter after creation and annihilating them or controlling them

> through the use of antimatter? Are the projects linked somehow? Can a

> singularity be controlled in this fashion?

Nevermind the technical difficulties you fundamentally misunderstand
the natur of Black Holes.
Energy curves spacetime. Antimatter and matter annihilation only
changes the form of energy but energy itself is conserved.
A BH made from matter grows if you feed it energy in the form of
antimatter. A Blackhole is neither matter nor antimatter it's spacetime
curvature.
A Blackhole created through the collapse of matter and a blackhole
created through the collapse of antimatter will not annihilate each
other.

Frank.