Black Holes

[Det. Bart Lasiter]

Yes, but having theories here in real life and in the field of physics/quantum mechanics and implementing said theories in a game are two entirely different things.

[wedge2211]

First, let me introduce myself properly...I'm a physics major at Williams College and have taken a number of courses that dealt with black holes (though I must admit I'm not taking the general relativity course offered at the moment in leiu of writing an experimental physics thesis).

 

Vader, from a layman's perspective, your explanations are pretty much accurate, with a few tiny modifications:

 

Black Hole's are simple, they are a large amount of mass compressed into a small space, if our sun became a black hole it would have the same gravity as our sun did. However, the process of turning into a black hole would first involve a super novae and then a star emitting extreme amounts of radiation

 

A clarification: not only do black holes have a large mass, they have a large mass compressed into an infinitesimal space. That is, the all the mass of a black hole occupies a point at the center of the black hole with no volume whatsoever. Think for a moment: if light cannot escape a black hole's gravitational pull, why should the matter making up the object's mass be able to withstand compression? This point is called the 'singularity' of the black hole. Now, the event horizon of a black hole is a different matter entirely, and can actually be quite large. The event horizon encloses all the space in which photons (light) cannot escape the black hole's gravity. If anything--you, a photon, a Corellian Gunship with engines boosted--goes into the event horizon, it never comes out. The imporant thing with tidal forces is the diameter of the event horizon (which is coupled to the mass of the black hole). Tidal forces result from a difference in graviational pull between points at different distances fromt he black hole's event horizon, and smaller event horizons actually exhibit larger tidal forces than large ones do. What's even weirder is that any mass that enters the event horizon nearly instantaneously becomes incorporated into the singularity. ('Nearly instantaneously' meaning faster than the speed of light as would be viewed by observers outside the event horizon if they could actually see in.) This is because a black hole isn't just a really strong dent in spacetime like a star is--at the singularity, spacetime actually is not well defined at all (hence the mathematical term 'singularity'). Imagine Carl Sagan's rubber sheet, stretched taut, with a bowling ball sitting in the center: the bowling ball is a star, and the rubber sheet is spacetime, and a ping-pong ball falling into the dent in the rubber would be experiencing the star's gravitational pull. To make a black hole, you would have to poke a tiny hole in the rubber with a pin, and stretch the hole down towards the ground, making a 'dent' in the rubber sheet that stretches towards the 'singularity.' Actually, to really make a black hole, you would have to keep stretching the rubber down that hole forever--spacetime itself actually moves into a black hole. That's how objects within the event horizon travel 'faster' than light. To them, they are travelling slower than light, but if we could see them, we'd see their spacetime moving--at nearly the speed of light itself!

 

The creation of a black hole does not require a supernova, just a gravitational collapse. However, in the real universe, we don't really see the one without the other--a giant star exhausts its fusion fuel, collapses in on itself, the resulting compression fuses many of the heavier elements in the star in a titanic explosion that blows away the outer layers of the star, and if the remaineder of the star has enough mass and is in a small enough space, it can overcome neutron pressure and collapse into a black hole.

 

As for the whole philosophy/simulation deal...

 

Black holes were first proposed as a solution to the equations of Einstein's General Theory of Relativity, after the theory had been accepted (and experimentally confirmed) for about forty years. So right from the bat, black holes were predicted by a theory that has been generally recognized to be consistent with the observable (macroscale) universe. Black holes are not just the result of some mathematical model on some obscure physicist's computer somewhere--they are an analytical solution to Einstein's equations. (You can do that math by hand. Well, a mathematician or a physicist could do that math by hand.) I will certainly admit that they are a crazy idea, though...Einstein himself was one of the first people to dismiss them as a misapplication of his theory.

 

Sicne then, black holes have been experimentally observed. We can't see them, but we can measure them. There are a number of ways to do this: first, we can detect black holes that orbit stars, because the orbit of the star will be perturbed enough that we know there's a huge mass nearby, even though we can't see that mass. Second, gravitational lensing can bend starlight around a black hole, distorting its image in our telescopes and allowing us to infer the existence of a large mass (some of the more dramatic lensing effects are known as 'Einstein's Crosses'). Third, as Athanasios mentioned, if a particle gets too close to a black hole but is not on a trajectory into the event horizon, it may be accelerated to such a high speed that it will give off high-energy X- and gamma-rays. This is particularly useful for locating spinning black holes, or black holes with magnetic fields. The important thing is that all these effects have been observed, and in many cases the only consistent explanation for the existence of those effects is the existence of a black hole.

 

[/physics rant]

[ScorLibran]

First, let me introduce myself properly...

Ah, I thought you held some scientific education based on your other posts. I'm a degreed Aerospace Engineer myself (Auburn University, 1990), although I've since worked exclusively in IT management since then. In college I also took quite a few physics and advanced mathematics courses.

 

Although science fiction is traditionally a mix of science fact and fantasy, Star Wars leans more towards fantasy than most.

 

A point of evidence regarding travel exceeding the speed of light: in Han's words the Millennium Falcon can do ".5 past light speed". Past light speed? What's commonly referred to as "faster than light" travel in sci-fi is often (in more detail) portrayed as either the use of wormholes (currently theoretical) or by means of "folding space" (also theoretical).

 

Many theories on the forefront of science (circa the most recent 100 years) are uncertain, and will be until we have the means to gather direct evidence - for instance with black holes, although we have more evidence of the nature of black holes than other theoretical phenomena - but travel that's actually faster-than-light seems to me less likely based on current knowledge than travel via either wormholes (if they exist as predicted) or by some form of a transdimensional folding of space by extreme mass displacement.

 

 

edit:

Oh yeah...to make my point. Since there are many other factors which delve into "pure fantasy" in Star Wars, flying past a black hole on a space map in this game doesn't bother me much.