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Ok, we need to keep this to fantasy really, because this isn't a science fiction guild. So, if we can use science, and science fiction as references only, this topic has the all clear to continue.

If we can talk about black holes in a fantasy context...let's go.

I don't think we're going to find people that walk on their hands, etc, but otherworldly phenomena, probably.

Earth to Berzerker Prime!

I and many other students of physics can tell you a great deal about what happens as you approach a black hole or what happens when you're in orbit around it. But the long and short of it is that it's an open question as to what happens when you get to it. It's even possible that the relativistic forces are such that length contraction goes wild and a particle can never actually reach it (meaning, in essence, that there is an infinite space within an infinitesimal point).

Berz.

That is one school of thought, yes.

Berz.

True, but a TV wouldn't have enough mass to become a black hole in the first place. Our own Sun doesn't even have enough mass.

It takes a truly gigantic star to become a black hole because the gravitational pull has to be so huge that it overcomes the subatomic strong force, that holds atoms in their structures. Without that, the star's mass can't collapse far enough. And that only happens when the star has burned up all its fusion fuel, which is when it hits Iron.

A star begins by fusing together two Hydrogen atoms into Helium, then fuses three Helium atoms into Carbon. Our Sun will do this, and then die out, collapse into a white dwarf and cool to a black dwarf. But more massive stars will go on to fuse higher elements together until it gets Iron.

After that, though, it takes more energy to fuse together Iron than it gets out of the reaction, so fusion stops completely. When the fusion stops, there is no longer an outward force pushing away from the star's center of mass, so gravity takes over, goes wild, and pulls everything in, impossibly close together, and the star's mass collapses down to a single point creating a black hole.

The freakiest thing, I've always thought, was that any orbiting planets that survive the massive fluctuations in the star's size that happens as it fuses higher and higher elements together will still orbit the black hole just as it orbited the star. The entire time the planets orbited the star, they orbited the star's center of mass, which is where the black hole would form. So, to the planet, nothing's changed and it just keeps right on orbiting as if nothing's wrong (except that it will not-so-slowly freeze, since it's no longer getting energy from its parent star).

This has been your Stellar Physics 101 for the day...

Berz.

In the case of the LHC, people are latching onto E=mc^2 (though, technically, there's a factor missing there, but at the speeds we're talking, it may as well be 1) and not understanding it correctly. What Einstein's famous equation tells us is that mass and energy are ultimately the same thing. There have been numerous cases where we have been able to convert mass into energy, but not one where we've been able to do the reverse. Why? Because it takes a freaking ridiculous amount of energy to create the corresponding mass. The theory is that the LHC might be able to gather enough energy into an atom in order to do it for the first time.

The thing is that it would create such a minuscule amount of mass that there is just no way we will see sudden, rampant black holes raging across Switzerland. People have simply sensationalized the idea of making mass out of energy.

It's BS, plain and simple.

Berz.

LOL! I had better! It's what my degree is in! mrgreen



Well, it isn't to say that an orbit can't decay. Keep in mind, such a system is only the simplest version of a system. Once another large mass enters the system and alters orbits through gravitational interactions, all bets are off. If an orbiting mass speeds up, it can eventually reach escape velocity and drift off into space. If it slows down, its orbit will decay and it will fall in. All it would take is a large enough passing mass pulling one way or another and either speeding it up or slowing it down.

Berz.

It would have to be a very big meteor, like the size of a moon or a second small planetoid, and it would depend on the direction in which it passed the planet. If it passed in front of the planet (that is, where the planet is going to be in its orbit in the near future), it could speed the planet up, in theory. If it passed behind the planet (that is, where the planet had been in its orbit not too long ago), it would slow the planet down and it would spiral into the star. In either case, though, it would take a biiiiiiiiggg meteor.

If you want to have a wandering planet, I'd find some way of getting rid of the star it orbits. But you have to actually get rid of the star's mass or you don't get rid of the force that pulls your planet into an orbit.

Berz.