As the shell collapses in on itself, the energy becomes so dense that its own gravity focuses it down to a single point and a black hole is born.

…but photons are massless and therefore have no gravitational influence. :\

I concur 100% with Hon. Salacious B. Crumb and Lawrence B. Crowell.

Don't feed this troll Anaconda (which should be the prerequisite by other users here.)

I mean. What fool would label himself a "heretic"? To me he is more like a sick-in-the-head zealot? To me it sounds like this individual just wants to be a martyr and victim towards his personal cause.
It is clearly not about science, religion, or anything else, it is all about him and his self-centered egocentrism
Science?

"Anaconda has nothing to do with it."

Yes he is a NUT, but I'd add, he is really still in his narrow-little shell. Pity.

The irony is in the feeling of scientific prosecution that he feels… At an age where the scientific community has for more than a century created an environment where challenging existing notions is protected and encouraged..

All of modern physics is a result of people completely revising or upending the prevalent understanding of the world..

What some folks don't get, however, is that not every view that revises or upends the current understanding is necessary valid – it might just be a completely unfounded pet theory advocated by a NUT.

NUT NUT NUT NUT NUT!!.

There, did it again.

This article is not a judgment about the physics of black holes, but rather about engineering concepts for black hole power.

Don't feed trolls. Anaconda is a pseudo-science exponent. Plasma cosmology has been rejected by the scientific community.

LC

Sure, I got you: Fantasy is more fun than reality.

But that ain't Science.

Of course, Crumb jokes about "burning" heretics at the stake.

Oops, I meant "deflagation", how careless of me:

As in, "Pity deflagration doesn't work with some people, here. It's probably illegal to do so".

What do you say when somebody reveals their religious fervor?

"Science has nothing to do with it."

Anaconda has been black banned as a troll in this group.

Just ignore the jackass, please.

Thanks

One article is about a highly hypothetical device relying on extreme physic and that has at its core an astronomical phenomena.

The other article is about a comparatively "straight forward" engineering implementation.

This is a web site for Astronomers and Astro-physicists… Which do you think will be of more interest ?!

That said, you need to be careful, since you're moving from the purely delusional phase to the paranoid.delusional phase. That's not good for your credibility… If everyone thinks you're out to lunch, you should carefully consider the possibility that indeed maybe breakfast's over and dinner is not yet served.

just my 2c, of course.

A key parameter in a Space Elevator design is the Characteristic Time Constant, which is a measure of how long the system can transport its own weight into orbit.

Read more at http://www.spaceward.org/elevator-feasibility

Ben

Making and controlling a micro black hole would be a daunting problem. To see that it is hard to build a box, all one needs to appeal to is Gauss' law. A shell of material that is the source of a static field, whether gravity or electric, has a constant potential inside. Force is the gradient of a potential, so enclosing a charge or a gravitating point-like object with a shell does not induce a force on it. So you can't confine it and guarantee it will not drift and eventually bump into the shell. So dynamic control is required which would be tough.

LC

Apparently fantasy is more interesting and enjoyable than reality for this crew.

(Universe today deserves credit for the juxtaposition of the two posts.)

That's a good thing.

Because when you are talking about propulsion systems, you are talking about real engineering and physics that have been confirmed in a laboratory, no if's, and's, or but's.

That's where the "rubber meets the road".

And as much as the "black hole" crew believes in the reality of "black holes", there is NO laboratory confirmation that any of the supposed scientific principles that support "black holes" actually exist.

The collider might bring some, who knows, or bosons from the future might sabotage it again

What this little exercise should do is concentrate the mind on the lack of ANY laboratory evidence that "black holes" exist.

My first thought when I read the title was "What Clarke novel had those black hole powered space ship, only they were for interplanetary use." Or was it a Varley novel? I am have a foggy mental over this, once again.

And then I thought of Anderson's "Tau Zero". Okay, less us say Mr. Crowell's math is off or someone is motivated to actually build this puppy. You pointed it, i dunno, that third star on the left and go until morning. And you get to .9999999 C or whatever.

Can you turn it off and restart it at will? You are going to have to a 180 and restart it to decelerate. Is that possible?

Maybe you will two of these boosters (like two SRB pointer together). Fire one to get to speed and throw it away when you get there and then fire number two to slow it down.

What, you wanna come home? Then you will need four. Do these things even have a "shelf life"?

Tricky

This goes into a general problem of how to put a black hole in a "box." It turns out there is no perfect box, except one which general relativity provides — the anti-de Sitter (AdS)spacetime. This is a whole universe of sorts. This is a theoretical setup, where the AdS is a field theoretic map of sorts from our entire universe. So we are not going to be doing that obviously in some engineering sense.

LC

And how large would the particle beams need to be to "anchor" the ship to the black hole?

LC

You are correct with the linear mass density figure, but start with a Carbon Nanotube material that has a specific strength of 40 GPa-cc/g, and see how much cable is required to carry a 20 ton climber… you'll be surprised, as I was a few years ago. I used to have in mind the multi-megaton Arthur C Clarke vision, but it's a mazing what a little bit of math can cure.

Such a strong magnetic field would also interfere with sensory equipment and communications, assuming there would be anyone to talk to out there. I suppose during the high speed travel, all cell phones would need to be turned off!

I kind of think that navigation at near light speeds would be very difficult. I suppose you could have predetermined "jump points" and hope there are no objects in the way.

Lastly, wouldn't it need to be a gradual acceleration to keep the crew from being splattered all over the back of the bridge?

Then there is the little problem being, the faster you go, the more mass you have… which means you need more propulsion.
Why can light move as fast as it does? …because it doesn't have mass.
In theory, you would be better off using some sort of fission device, and make the most of E=MC^2 to move around in space. The heck with black holes, lets use the strong nuclear force.

Even better… find a way to compress the space you want to move into; then you wouldn't need to travel quite as fast, since you are basically making space come to you.

Shielding a ship from harmful radiation is simple… you simply do the same thing Earth does. Something we've been able to do for over a hundred years. Create a magnetic field.
Shielding a ship from particles using energy or a form of plasma is probably within our reach now, and I would bet we see something feasible within the next 10-20 years.

& int dt = 0

& = delta, and dt = dx/c, c = speed of light. Well the speed of light in a medium changes by an index of refraction c–>c/n, where n can vary with position n = n(x). The problem is equivalent to the extremization in classical mechanics and leads to the Euler-Lagrange equation.

As for information, yes a black hole does return all its information. In fact we can say that information is generally conserved. Yet it does not remain available, or correlated. Information can be encrypted in various ways, or it can be dispersed. That is the measure of entropy. The Susskind-Preskill win over Hawking is over this matter. Hawking insisted that information was destroyed, while it has been found that it is simply encrypted by some grand algorithm of the unvierse into forms that are much harder to cypher.

The wormhole connecting up the outside world with the interior of a black hole would reduce the area of the black hole. Entropy is by the Bekenstein-Hawking result related to the event horizon area of a black hole A = 4piM^2 with mass M by

S = kA/(4L_p^2),

where L_p = sqrt{G hbar/c^3} or the Planck length, k = Boltzman constant. So we can think of the entropy of a black hole as the number of units of Planck area on the event horizon. The reduction in the area of the event horizon means that entropy is reduced, but if presented to the outside world without encryption then the second law of thermodynamics is violated. For instance one might imagine rescuing an astronaut who fell throught the BH.

Now this presents some other funny things, for you might rescue the astronaut, bring him back and you might be able to have him see himself time dilated and redshifted above the black hole horizon. This then leads to another "no-go" theorem in physics that you can't clone quantum states. Yet a traversible wormhole would permit you to do that.

Worm holes would allow one to solve an NP problem in P time. In fact it might well mean you could solve all P-space problems with equal efficiency. A factorization problem can be solved in a time loop so the closed timelike loop exists with the problem solved. It is like the old science fiction idea of getting instructions on how to build a time machine, building it and then sending the instructions back in time to yourself.

These things simply don't happen, at least if the universe is at least not logically self contradictory.

LC

We might also try to find black hole deposits so we do not have to create them just harvest them.

I am not an expert in black holes, but I saw this formula that you would need a 228 metric tons of black hole so it can exist for 1 second. But if we let it run in a circle near the speed of light would it stay longer like 1 hour a black hole?

Also, traveling near the speed of light, what happens if you hit a dust particle? (Answer = Boom!)

Also, wouldn't radiation thats coming from space in front of you be blue shifted to higher energies?

This is Fermat's theorem, and it has to do with the conservation of phase space volume for systems in classical mechanics.

Even if it is one of Fermi's theorems, it doesn't say much as a reference.

More to the point here, BH's are outside of classical mechanics, so AFAIU all bets are off. What will happen at the transit between classical to BH regime?

This would violate the second law of thermodynamics for black holes.

Sorry to pick on the comments, but I don't get the idea here. Black holes will eventually give back their information to the universe, so why would a worm hole or similar information channel be a problem for them? Wouldn't they just diminish in surface area (volume) faster?

This doesn't save Alcubierre's drive though. Famously, it depends on the solution (and it's confined transit volume) being already transiting at supra-light speed at it's creation. As we can't get from here to there without the drive, we can't get from here to there to make the drive! (o.O)

Causality can be a bitch.

in other words time machines. There you have causality issues

Worse; as Scott Aaronson points out time machines would also implode the algorithmic tower of complexity. (Physics with time travel becomes unboundedly algorithmically powerful, or conversely everything is equally easy.) As this isn't so, they can't exist.

Which of course means that FTL drives and communication can't exist either. No loop holes.

@ Dr Flimmer: The Alcubierre warp drive is a solution to the Einstein field equation. There are a fewf problems though. The solution violates the weak energy condition that the momentum energy component T^{00} >= 0. This means the quantum field which is the source of the solution is not bounded below with a discrete energy spectrum. This is a disaster for physics. Another problem is that any such configuration of spacetime would permit one to enter a black hole, acquire information about its interior and then return to the outside. This would violate the second law of thermodynamics for black holes. Finally, such configurations can be converted to solutions with closed timelike curves, or in other words time machines. There you have causality issues and properly define Cauchy spatial surfaces of data.

@Graff: There are issues along these lines. The questions are open because metric back reactions are a classical response to a quantum process. Hawking radiation is derived in a semi-classical setting, where the black hole is classical. In what I am working on gravity is not really quantized as such, so as the BH becomes smaller there its radiative processing departs from what might be expected. It is possible that it actually slows down as it reaches the 10^6 Planck units of mass and leaves behinds a remnant which is a topological "knot" in spacetime.

LC