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Black Holes

Spaghettification or Jump?

Yes, but I think I would have to argue that the game-descriptions for gravitics/contra-gravity and/or any given FTL-Drive are specific to their operations under normal space-time conditions (relatively speaking). Close to an Event Horizon surface, I would think that the physics of their operation would be a more complex relationship (speaking intuitively from a make-believe science standpoint, of course :) ).
If the choice is spaghettification or Jump? I chose Jump.

Yes, the Ref gets to sling gobs of negative modifiers at us, but I have a counter. :D

Jump leaves Normalspace for Jumpspace. Our ship will transition out of the black hole's space-time into Jumpspace-time so we get out of the black hole (with some very scary new physics data) the only way possible, by not being there. (:devil: It's in the details!)
 
If the choice is spaghettification or Jump? I chose Jump.

Yes, the Ref gets to sling gobs of negative modifiers at us, but I have a counter. :D

Jump leaves Normalspace for Jumpspace. Our ship will transition out of the black hole's space-time into Jumpspace-time so we get out of the black hole (with some very scary new physics data) the only way possible, by not being there. (:devil: It's in the details!)

you likely don't gain much. all the data from the horizon inward is of stuff above you, as even light is down only...
 
Hey now...

you likely don't gain much. all the data from the horizon inward is of stuff above you, as even light is down only...
Still, it is officially new, since one assumes that this hasn't happened before. And it is empirical data, not theory at that point and that you could in theory sell. I mean once you figure out where you are, limp to a port, hope it's friendly, repair the ship, probably replace the drives and of course sell our terrifying story of heroic and scientific daring do (not mentioning how we sort of wandered a bit too close thanks to someone, but not naming anyone...Nav...cough, cough). :D
 
It does give one pause to think about the effects of a black hole on Jump Space. Since there's coherency of matter in jump space, although due to a field around the ship, what effects, if any, does jump space have on a black hole, and / or vice-versa?

Are there black holes in jump space? Probably not since black holes are theorized to be portals to other areas of space. I tend not to believe that theory, but one wonders if within Jump Space itself there isn't some similar phenomenon.
 
Jump leaves Normalspace for Jumpspace. Our ship will transition out of the black hole's space-time into Jumpspace-time so we get out of the black hole (with some very scary new physics data) the only way possible, by not being there. (:devil: It's in the details!)

Ah, but dont forget one little problem with Black Holes - the gravity does a number on space and _time_. And the closer you get to the event horizion - from the external universes view - time slows down and stops (it's a bit more complicated with spinning black holes where time dilation can occur in the ergosphere). So by the time your do the math, spin up the drive and jump out, a trillion years may have passed when you pop back into normal space (assuming you survive).

There are two other fun effects though. The first is that since the singularity is 0 volume diameter, there is no minimum distance by the rules you can jump fom it.

The second is more problematic - space/time is curled up so much inside the event horizion that literally whichever direction you go, you are always heading towards the singularity (which is why light can't escape. Its not speed which is the problem, but that spacetime is bent so badly the very concept of 'travel away from the singularity' is meaningless). So jump away but your exit point may just be closer to the singularity.
 
Since we're talking about black holes, I will mention the recent movie Intersteller. In the film is an accurate physical rendering of a black hole. As in real astrophysicist derived the maths to describe what you are looking at, and had the film maker CGI department render it using that.
 
It would be most interesting to exit jump 1,000,000,000,000 years in the future.

I think the issue is probably a bit more straight forward than that. And that is as your ship generates a jump field, what happens to the actual field or energy in the field? Does it stick to the ship's hull, or does it even get a chance to emanate equally all around the hull?

I'm curious if you could expand on the time dilation issue. Even though the gravity there is so strong that it's warping space, how is it that your mass energy system, you, the ship, crew and everything else, are going to get flung into the future?

I'm still unclear on this.
 
Still, it is officially new, since one assumes that this hasn't happened before. And it is empirical data, not theory at that point and that you could in theory sell. I mean once you figure out when you are, limp to a port, hope it's friendly, repair the ship, probably replace the drives and of course sell our terrifying story of heroic and scientific daring do (not mentioning how we sort of wandered a bit too close thanks to someone, but not naming anyone...Nav...cough, cough). :D

Fixed that for you. :D

Relativity you know.
 
I'm curious if you could expand on the time dilation issue. Even though the gravity there is so strong that it's warping space, how is it that your mass energy system, you, the ship, crew and everything else, are going to get flung into the future?

It's warping space/time not just space.

With general relativity the closer something is to a mass (a source of gravity distortion of space/time) the slower time goes compared to someone who is further away from the gravity source.

For example - if you compare two clocks, one close to a gravity source and one further away - the clock deeper in the gravity well ticks slower. This has been experimentally tested and is used to correct GPS (in addition to special relativity compensating for their movement) though it is barely in the nanoseond range for Earths gravity.

The closer the ship gets to the black hole, the slower time passes for them (the same as if they accelerated to near light speeds). So while it may only take then 10 minutes to charge and active the Jump drive from their frame of reference, days/years/centuries may have passed for people not near the black hole. The time dilation gets worse the closer you get. Nearby the hole may only slow you down by a few seconds, while right on top of it can turn a second (your time) into a million years (everyone elses time).
 
I guess what I'm really asking is how close do you have to be to experience significant time dilation effects.

Like I wrote earlier, I think a lot of science types have sci-fi engineering ticking in the back of their skulls when they say you can't escape past the "event horizon". That assumes that you've capable of travelling at C, or greater than C, and that you can therefore escape just before you come to the event horizon.

But it seems to me that realistically you'd feel the effects long before then. It strikes me that the Event Horizon is merely a layer of light demarked by the physics of gravity, and not really a transitional boundary where if you go beyond it, then all kinds of strange stuff starts happening.

Another interesting aspect is this; how do you know how close you are to a black hole?
 
It does give one pause to think about the effects of a black hole on Jump Space. Since there's coherency of matter in jump space, although due to a field around the ship, what effects, if any, does jump space have on a black hole, and / or vice-versa?
According to Marc Miller, the effect of gravitational sources on jump is tied to the diameter of objects and not their gravity. Accepting that (which I don't IMTU), a black hole should have no effect on jump traffic at all, especially if you add the provision that the larger object affects the smaller.


Hans
 
Another interesting aspect is this; how do you know how close you are to a black hole?

If you measured the mass of the black hole before approaching it (always a good idea), you can calculate distance based upon apparent gravity and tidal forces. You may need to correct for the relativistic effects, but that's not hard (for a computer) either.

All of this supposes that there isn't any matter falling into the black hole other than the PC's ship. If there is, it usually forms an accretion disk, which will glow brightly with all sorts of light waves (up to and including gamma rays) and should give you a nova bright beacon as to where the black hole is, exactly.
 
I guess what I'm really asking is how close do you have to be to experience significant time dilation effects.
Technically? You're experiencing them already. From Earth. From Luna. From Sol. From the invisible behemoth at the center of the milky way. And from the velocities relative to same.

They approach zero, but are not zero.

If you want significant, let's set a significance boundary... is it 1:01:00=1:00:00? or 1:00:00.000001=1:00:00? or is it 1:00:01=1:00:00?

Time is entirely relative to what the gravity is and how fast you're moving, as perceived by something else.
 
I guess what I'm really asking is how close do you have to be to experience significant time dilation effects.

My bad. Apologies.

The equations for general relativity are way out of my depth, but thankfully there are simplified versions here

Essentially for a black hole it is t0 = tf * SQRT (1 - rs/r)

T0 is the dilated time
T1 is ''normal time'
rs is the event horizon radius.
r is your distance.

For a hole 100km in diameter with you at 110km, T0 = 0.3. Time slowed by 1/3

For the supermassive hole at the centre of the milky way
rs = 12000000km
You at 30,000km away (1 trav hex): T0 = 0.05. Time slowed 20 times
You at 1000km away: T0 = 0.009. Time slowed about 100 times
You at 1 km away: T0 =0.0003. Time slowed about 3000 times.
When you hit the event horizion time is slowed infinitely (the equation breaks down).

With a big black hole though, you can snuggle right up to the event horizion without having to worry about being spagettified. The tidal forces only get strong enough to pull you apart inside the event horizion. If the hole is feeding of course, the accretion disk radiation would fry you first.

This is only for a static non-rotating black hole (ie: a purely theoretical one). The moment you start the hole spinning you get frame dragging which makes the time dilation worse. And I wont even pretend to understand the math that I found regarding it. :oo:
 
Yeah, thanks. I remember my engineering physics instructor passing out a sheet with relativity equations ... I'd just forgotten. It was stuff that was beyond, or derived from, E=mc^2, and I think all of it pertained to dealing with the physics of particles of various sorts.

Something else for me to write up.
 
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But it seems to me that realistically you'd feel the effects long before then. It strikes me that the Event Horizon is merely a layer of light demarked by the physics of gravity, and not really a transitional boundary where if you go beyond it, then all kinds of strange stuff starts happening.

I do not know what you meant by a layer of light demarked by the physics of gravity, but otherwise, you're right. The event horizon is an artificial distinction to the item falling into the black hole. It is "the point of no return," for those bound by the speed of light, but that's hardly important to an infalling object that wasn't going to be able to get to lightspeed to escape anyway. The only real difference is that that is when the emited light from stuff falling in ahead of it goes from almost nothing to nothing. Long before then, you would be spaghetified, and before that, crushed by gravitational tides.
 
When I hear about the event horizon, the gist I get from whatever physicist is talking about it, is that after the event horizon all the time dilation and other strange effects begin to take hold. At least that's what it sounds like some times, but I'm guessing what they really mean is that all the time dilation and stretching probably happens long before then.
 
Erm, does F = [G(m1 * m2)] / r^2 still work for black holes, are is there a relativistic equation for a black hole's gravitational force?
 
When I hear about the event horizon, the gist I get from whatever physicist is talking about it, is that after the event horizon all the time dilation and other strange effects begin to take hold. At least that's what it sounds like some times, but I'm guessing what they really mean is that all the time dilation and stretching probably happens long before then.

The size of the Event Horizon of a static (non-rotating) Black Hole (the Schwarzschild radius) is given by:
Rs = 2GM/c2

The time dilation due to gravity (for a static (non-rotating) black hole) is given by:
td = t {1 - [2GM/rc2]}1/2

where:

td is the dilated time in the gravity-well
t is the normal time at a distance far from the black hole (i.e. where time passes at a rate of 1 second per second)
Note that combining the two above equations yields:
td = t {1 - [Rs/r]}1/2
This means that as r appoaches Rs time moves slower and slower until one reaches the event horizon (Rs = r), at which poiny td = 0 (i.e. time passes at 0 seconds per second as seen from a far distance - in other words, time stops at the event horizon).
 
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