It seems that whenever the mainstream news sites have an article that deals with black holes or some other amazingly dense material, they always tell how much a teaspoon of it would weigh. OK, I’m holding a teaspoon out at arm’s length and Scotty beams it full of black hole.
What happens next?
First, you’d drop the teaspoon.
I think you’re thinking about neutron star, not black holes. You couldn’t get a teaspoon-full of black hole–they’re stranger critters than that. But a teaspoon-sized black hole would weight about as much as a planet.
Of course, even with a neutron star, you couldn’t get a teaspoonful by itself. Neutronium (the stuff of which neutron stars are made) is stable only under the extreme pressures found in a neutron star. If you tried to isolate a spoonful of it, that spoonful would explosively expand to some more reasonable density, and you’d end up burried under a mountain of (probably) iron.
Unless I’m mistaken, the singularity of the black hole is essentially a one-dimensional object. It’s infinitly small - so any size black hole would fit in a teaspoon. The event horizon of the black hole can be much, much larger, and that’s what’s being referred to when someone speaks of a black hole’s size, but that’s a mathematical result of the black hole’s gravity, not a substance with weight.
I always wanted to know what would happen if I scooped up a teaspoon of this stuff but mother always said to just let those neutron be, they’re just trouble.
A cubic centimeter of neutronium is about 10^14 grams = 100 million tons. Don’t try this at home. If I figured correctly, that’s equavalent to a conical pile of rock 200 meters high by almost 500 meters at the base. Not exactly a mountain, but a fair-sized hill.
As has been pointed out, you can’t really have a teaspoon of black hole. I suppose you ould try to mess with the units, such that you have a black hole whose event horizon has the same volume as one teaspoon. A teaspoon is about 5 ccs. A sphere with volume = 5cc has a radius of just over 1 cm.
Interestingly, the mass needed to give you a black hole of one centimeter radius is about 6 x 10^27 grams, which is the mass of the Earth. So, if you squeeze the Earth into a teaspoon, you get a black hole. Kewl.
OK. Having miraculously survived the neutronium explosion, I whip out my communicator and tell Scotty to try again, only this time, to be sure a put a force field around the teaspoon of neutron star matter. Scotty makes some wiseass comment about me not knowing the difference between a black hole and a neutron star. I make a rebuttal about his drinking problems and we both have a good laugh. He beams another teaspoon of neutronium to me with a properly configured force field.
Now what happens?
NO I want to know waht happens w/o a force field. Will I get a lump of iron or a big hostess ho-ho?
Now you break your wrist trying to hold the teaspoon?
This reminds me of neutrinos and black holes in which it turns out that a chunk of neutronium 85 meters thick has the same mass as a chunk of lead 1 light year thick (assuming the other two dimensions are equal, e.g. 85 m x 1 m x 1 m neutronium = 1ly x 1m x 1m Pb)
Imagine the scattering cross-section on that baby!
Wouldn’t you rather have a little nondairy creamer with your coffee? It’s less fattening than neutronium.
I admit I slept through geometry, but if it’s infinitely small isn’t it zero-dimensional? I thought lines were 1-dimensional.
It sounds like if someone had a teaspoon of black hole, it would throw the earth out of orbit. Then we’d have to have a law against posession of black hole. (“But officer, I only had a little bit”)
Depends on the properties of the force field. To keep the neutronium in it’s dense state, we assume it’s applying the same force to the sphere that the neutronium was under in its natural location. The first question is - does the force field holding it together also prevent outside matter from interacting with it?
The second question is, what’s holding it up? If the force-field is also holding it in place, you’ve got a solid sphere of neutronium floating in the air near you.
I’ve never tried the experiment, but I’d think that the matter would come out in the form of super-hot plasma and disassociated elementary plasma. Think of it - you have a 100 million tons of matter squeezed into the size of a teaspoon. The only thing holding it stable is the tremendous gravitational pressure it’s under. When you remove that gravitational pressure, the matter will rebound outwards with a force equal to the pressure that was holding it in. Boom.
Depends on the properties of the force field. To keep the neutronium in it’s dense state, we assume it’s applying the same force to the sphere that the neutronium was under in its natural location. The first question is - does the force field holding it together also prevent outside matter from interacting with it? If not, air molecules around it will wander into the force field and be crushed into the surface, addind to the neutronium mass. If the forcefield grows with the mass, the neutronium lump will slowly grow in size as all the nearby air is sucked into it. I suspect that the gravitational force of the lump will be nowhere near great enough to pull nearby objects into it, so it’ll just act like a vacume sucking in air. Don’t touch it, and you should be safe.
If the force-field contains matter in both directions, nothing in particular will happen. While contained, neutronium won’t emit radiation or do anything else particuarily dangerous.
The second question is, what’s holding it up? If the force-field is also holding it in place, you’ve got a solid sphere of neutronium floating in the air near you. If the force-field doesn’t support it, the neutronium will fall. Your teaspoon won’t even slow it down, nor will the ground under you - normal matter is a thin fog compared to neutronium, trying to hold onto it would be like trying to support a cannonball with a cloudbank. It’ll fall right through the earth, crushing or absorbing anything in its path.
I’ve never tried the experiment, but I’d think that the matter would come out in the form of super-hot plasma and disassociated elementary plasma. Think of it - you have a 100 million tons of matter squeezed into the size of a teaspoon. The only thing holding it stable is the tremendous gravitational pressure it’s under. When you remove that gravitational pressure, the matter will rebound outwards with a force equal to the pressure that was holding it in. So you really, really don’t want to be standing nearby when the force field drops.
(Sorry about the double-post - the board software decided to post the message when I was only half done writing it.)
I suspect that very few people indeed have done the experiment. 
I agree that it’d be some sort of plasma at first, but it’s not going to stay that way forever. What do you have when it cools down? My money’s on either hydrogen or iron, and I suspect iron.
Why iron, Chronos? I would think you’ll get hydrogen at first, but will the density be sufficient to fuse?
Yes Ian Fan, a single point in space has no dimension.
Geez, do they really expect us to believe that matter can be condensed into an infinite volume point singularity? How dumb do these scientist think we are?
Infinite volume, hah!
Woops, that’s infinite density, not infinite volume.
Either way, hah!
Not to pick a nit, but,
a teaspoon is five cubic centimeters.
The cube root of five is 1.7099
That doesn’t round off to one centimeter in diameter. Your black hole is a lot more massive than the earth. Five times as massive, in fact.
Doesn’t the prediction of the ratio of Hawking radiation to radius predict that such a black hole would “sublime” into hard gamma radiation rather quickly? Hours, I think I remember, or at the very most within a year.
Tris