Home: Vacuum
black hole vacuum cleaner   (+6, -6)  [vote for, against]
suck it up!

A teensy tiny black hole in a box with a pipe on one end. Comes with a brush tool, a crevice tool and one to clean up the other black hole related crap on hb I just been lookin' at.
-- the dog's breakfast, Mar 07 2007

Halfbakery: Vacuum Vacuum Vacuum_20Vacuum
There's some discussion of using black holes in the annotations. [jutta, Mar 07 2007]

Halfbakery: Schwarzschild radius warning labels Schwarzschild_20radius_20warning_20labels
What [lurch] remembers. [jutta, Mar 07 2007]

Charged black holes http://en.wikipedia.../Charged_black_hole
from wikipedia [GutPunchLullabies, Mar 08 2007]

[marked-for-deletion] bad science
-- hippo, Mar 07 2007

Thanks hippo! It's what I do!
-- the dog's breakfast, Mar 07 2007

Why is it so bad? You have to at least mention the huge output of hard radiation as the black hole chews through atmosphere.

Oh, and the extreme weight. And the danger. And the limited lifetime. And the power requirements for storage.

But is it actually impossible? I must say, I have no sense if a black hole big enough to absorb atmosphere quick enough to create a good suction could exist without crushing its container.
-- GutPunchLullabies, Mar 07 2007

//Maybe there are stable black holes that can be used instead of having to flush something round a U bend ?//

Mabye you need to re-read your physics - or perhaps you can explain how gravity can be turned on for some objects and off for others; in other words, provide us with a suggestion as to how it might be 'piped'?
-- zen_tom, Mar 07 2007

(+) The crevice tool really makes this one.

[admin: I'm ignoring hippo's mfd because it's meant to be funny, it works for me, and the annotations are good. Compare vampire-based generators.]
-- jutta, Mar 07 2007

It only works where the sun don't shine...
-- Ling, Mar 07 2007

I beleive I can provide that zen_tom... the actual cleaning power would stem from the atmosphere inside the box being continually absorbed into the singularity. It is air rushing in to fill this vaccuum that provides the cleansing suction at the end of the hose.

The reason the box could (maybe) avoid being sucked inside would be that all important parts are distant enough that the container holds up against the acceleration at that distance.

The question at hand is, is all this doable with a size under that of a stadium and a weight less than a battleship?
-- GutPunchLullabies, Mar 07 2007

after a short amount of use, its increasing mass and subsequent gravitational attraction would mean that it would swallow its containing device, then proceed to consume the entire planet as it made its relentless path to the centre of the earth...... a bit dangerous methinks.
-- xenzag, Mar 07 2007

I just did the calcs, and it turns out that pinging a black hole with dense atoms is like pinging the earth with bb's. Hey, where'd all of my black hole stuff go!? [+]
-- quantum_flux, Mar 07 2007

At least it would sort out Calcutta.
-- wagster, Mar 07 2007

I've been trying to find an old HB idea - about putting labels on products warning against crushing them below certain dimensions because of the likelyhood of creating a singularity. This idea needs such a warning label, but where did it go?
-- lurch, Mar 07 2007

I can see it now:

ACME gravitational vacuum bags CAUTION: DO NOT PLACE USED BAG IN TRASH COMPACTOR! Placing a used bag in a trash compactor may result in the formation of a singularity. ACME corporation will assume no responsibility for the creation of a singularity or the surrounding black hole. ACME corporation will assume no responsibility for any injury, personal property damage, or end of the world that may result from the formation of any singularity or black hole.
-- Freefall, Mar 07 2007

So, we've got a nano-tube black hole position detector with supercomputer and a black hole pinger which keeps the black hole in the middle of the vacuum cleaner chamber. All packaged in a portable device with a simple on/off switch.

All of this, and the subsequent danger to the rest of the world, just so Aunty can vacuum up the hair from Mr. Tiddles.

Sounds great!
-- Ling, Mar 08 2007

Why would you change a bag? It's not going to get FULL.
-- GutPunchLullabies, Mar 08 2007

No, but it'll get very HEAVY
-- hippo, Mar 08 2007

Presumably it is already too heavy to lift/possibly rest on the earth's crust.
-- GutPunchLullabies, Mar 08 2007

Such a thing would be extremely heavy - and since the only physical property a black hole has are mass, size, velocity and spin (i.e. no charge, surface tension, colour, reflectivity, aerodynamics etc) - the only way of keeping it from drifting to the centre of the earth would be by bombarding it from below with increasingly heavy projectiles I think this is the 'pinging' we've heard talk about - When you consider that each ping must be at more than 1x the last one, it's not long before exponentiation takes over and your pings start to look more like pongs.
-- zen_tom, Mar 08 2007

I thought we could give a black hole a charge if we dumped enough charged particles into it! Has sci-fi lied to me?
-- GutPunchLullabies, Mar 08 2007

I'm pretty sure all information, once it's been sent into the hole, gets lost, including charge. There would likely be an interesting boundary at the edge of such a hole in terms of electromagnetic fields - I don't know for example whether a field could be propagated across a black hole i.e. might it be possible to arrange a magnet such that to all intents and purposes, it only had one pole?

[edit] Actually, I take all that back - it turns out that just maybe, a black hole can have charge (so, in a Spanish Inquisition type manner, that list again includes mass, size, angular momentum and charge - nothing else). Which means that we might be able to suspend one, magnetically.
-- zen_tom, Mar 08 2007

Update: Wikipedia lists the three properties of a black hole as angular momentum, charge, and mass.

I was pretty sure this had to be the case, as charge is conserved in the universe (+ equals - overall) and destroying charge would violate this.
-- GutPunchLullabies, Mar 08 2007

I'd not heard or thought of a charged black hole before - such a thing must be quite strange.

If a thing has electrical charge, does it not also inherit some kind of magnetic field arrangement? And if that's the case, wouldn't that mean than a black-hole would have north and south poles? And if it did, that would violate the "no hair" hypothesis.

If it didn't and you were able to dump all your charge on one 'side' of the black hole, you'd be able to form a perpetually spinning dynamo, a revovling magnetic field, into which you could introduce wires, and extract current - the ultimate space-battery.
-- zen_tom, Mar 08 2007

There are lots of good ways to extract energy from black holes. Your space battery is simply converting angular momentum into electrical current.

However, I must take issue with the assertion that it is "perpetually spinning", it may have a lot of momentum but you will use it up eventually.

Oh, and also you need to exert force on the wires to keep them in place, neatly using up any energy you generate.
-- GutPunchLullabies, Mar 08 2007

<shakes fist at sky>
Damn you, Thermal Dynamics!

Still, the question remains about charge and hair. Am I right in thinking that charge must bring about a magnetic field, and that in turn, a magnetic field must have poles?

Furthermore, do magnetic fields follow gravitational geodesics? In other words, if we accept that spacetime is 'bent' by gravity such that light will follow an apparently bendy route when passing by a massive object - how are magnetic fields so affected?

Either they follow spacetime, or they don't. And if they do (which I suspect they must), would they end up bending in on themselves within the Swartzschild (or some other) radius? In other words, if a black hole has charge, is it able to express it?
-- zen_tom, Mar 08 2007

Since the field lines would originate at the center of the black hole, bending would not be an issue for the electrical charge.

I think that the magnetic field should be parallel to the axis of spin- thus basically motionless with respect to someone standing right next to the black hole.

The shape of the magnetic field is not influenced by gravity (I think), but it is dependent on the distance between the poles- something that is somewhat indeterminate in this case. I'm not sure how that would all work out. My guess would be that it would behave similarly to a spinning particle, like an electron or something, but with a charge of a million coulombs or whatever you put into it.

Oh. and what is all this stuff about hair? Is this the hair we have sucked into the vaccuum cleaner?
-- GutPunchLullabies, Mar 08 2007

You don't necessarily need energy to keep the wires in place and stop them rotating with the field. All you need is something to brace them against - a (rather large) structure between two black holes would do it, assuming it could deal with all of the other impossibilities that would entail.
-- david_scothern, Mar 08 2007

Actually, you do need energy. Anything you brace them against would be accelerated in the direction of the force acting on the wire.
-- GutPunchLullabies, Mar 08 2007

Meanwhile, in a parallel universe...."Honest, Mrs. Xyxl, I have no idea what hapenned. I just plugged in the White Hole power- duster, and all this alien-looking debris sprayed out of it all over the place...."
-- MaxwellBuchanan, Mar 08 2007

//All packaged in a portable device with a simple on/off switch.//

Hold on a minute - just how do you switch this damned thing off?
-- Ling, Mar 09 2007

I really hate it when people add interesting anno's to such a shitty idea. Don't you realise you are endangering the deletion and feeding the troll? Pah! -
-- zeno, Mar 09 2007

//I really hate it when people add interesting anno's to such a shitty idea//
What about shitty annos to a good idea?
Or shitty annos to a shitty idea?

What did they ever do to upset you?
-- Ling, Mar 09 2007

No, a black hole can't have a detectable charge since electromagnectic radiation can't escape it in any direct manner. This is why pinging it like a billiard ball is the only way to control its position and momentum. Also, since...

F=q(E+VxB), and V is all relative, then E and B are just two aspects of the same electromagnetic-field.

Finally, light has momentum, but it is wave-momentum. The light-photons trying to escape a black hole gain energy-frequency and lose wavelength or gain momentum. As the wavetrain gets smaller, the uncertainty in either the position or the velocity increases to huge numbers, and therefore the photons are doing something crazy or unpredictable inside a blackhole (like not escaping).
-- quantum_flux, Mar 09 2007

Electric charge is not radiation. Note, for example, an electron - it can just sit there and never emit any radiation whatsoever, and it still expresses charge. Electric charge is a potential field, not radiation. If a potential field could not be expressed by a black hole, then it would be unable to exert gravitation.
-- lurch, Mar 09 2007

Agreed [lurch] but I suppose the question remains whether charge (and magnetism) emit space independent potential fields or whether these fields are bent around the fabric of spacetime.

The pinging method of controlling a black-holes' position tends towards being rubbish over a period of time. If your black hole is 1 unit in mass, and you wish to 'ping' it enough not to fall through the floor and plunge to the centre of the earth, over some period of time, you will have pinged it with an equal 1 unit of pinging mass. At this point (however long it may have been) your black hole has a mass of 2 units. Then, after the next interval it's 4, then 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, 65536, 131072, 262144, 524288, 1048576, 2097152, 4194304, 8388608, 16777216, 33554432, 67108864, 134217728, 268435456, 536870912, 1073741824, 2147483648, 4294967296, 8589934592, 17179869184, 34359738368, 68719476736, 137438953472, 274877906944, 549755813888 etc - and that's after only 40 ping-intervals.
-- zen_tom, Mar 09 2007

Oh crap. this was only meant to be a throw away idea cos i was tired of reading all about other peoples black hole ideas (and feeling like a dumb shit for not understanding any of it......um I mean it was "outside my field of expertise") and now its turned into one itself. dunno about anyone else but I'm givin' it a bone.
-- the dog's breakfast, Mar 09 2007

I was born upset.
-- zeno, Mar 09 2007

In astrophysics, the no-hair theorem states that all black hole solutions of the Einstein-Maxwell equations of gravitation and electromagnetism in general relativity can be completely characterized by only three externally observable parameters: mass, electric charge, and angular momentum. Wikipedia, "No hair theorem"

Hey, I learned someting today!
-- GutPunchLullabies, Mar 09 2007

Logically, given an infinite amount of time, won't the entire contents of the universe end up in one black hole, or is there a "size" limit ?

I don't like the thought of this much and will make strenuous efforts to protest against it at Quantum court.
-- xenzag, Mar 09 2007

Actually, black holes decay at an accelerating rate. You get all of the mass back (as energy), and most of the information.
-- GutPunchLullabies, Mar 09 2007

All you got to do is ping the black hole with something that has even more momentum and an opposite direction than the black hole does....it's just like playing billiards, but with balls that stick onto each other in an inelastic collision.

Also, think about this.... if an electron is moving at a constant velocity relative to you, then it is giving off a magnetic field (as in a wire). However, if you are moving at the same velocity as the electron, so that it is at rest relative to you, then it is giving off an electric field. Usually it's both fields that is being emitted to some degree.
-- quantum_flux, Mar 10 2007

//ping the black hole// A black hole's position could be controlled by directing a stream of particles past the hole. The particles, in being deflected, would exert an equal-and-opposite force on the hole, much as a stream of water or air is deflected by, and attracts, a ping-pong ball.
-- spidermother, Mar 11 2007

[m-f-d] blah-de-blah.

I like this one, if only for imagining the perplexed little green faces of the residents of Trog, third planet from Camelopardalis, somewhere over the wormhole...

"Now just WHERE the fuck did all this cat hair come from?"

-- m_Al_com, Mar 12 2007

Damn, [MaxwellBuchanan].

I've gotta get up earlier, and check in more often, and read the annos more carefully... *sigh*
-- m_Al_com, Mar 12 2007

// Actually, black holes decay at an accelerating rate. You get all of the mass back (as energy)

Wow. So capture the energy (easy), and you're converting all that cat hair into electricity? So this becomes "Power producing black hole vacuum cleaner" and all those "it'll keep getting heavier" arguments are null and void!
-- TheLightsAreOnBut, Mar 12 2007

Yeah but then if you just dug a hole first (to the centre of the earth-jules would love it) and had your suction hose leading out of it...and to obtain a nice small singularity, just squashed a couple of wimps together, (past their schwarzchild radius, nothing earth threatening ~ really) Auntie and Mr Tiddles would love you.
-- the dog's breakfast, Mar 12 2007

Yes, it's decaying, and yes you can extract energy from that. The problem is that the smaller it gets the faster it evaporates.

So you have to make it big enough to last more than a yottasecond, but small enough to put out usable energy. In this case it also has to be big enough to eat hair and small enough to lift...
-- GutPunchLullabies, Mar 13 2007

//Mabye you need to re-read your physics - or perhaps you can explain how gravity can be turned on for some objects and off for others//

Simple! since everyone knows that gravity is the result of spinning, you simply stop the blackhole's spin. to turn it back on, just get it revving again.
-- the great unknown, Sep 06 2007

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