15 replies to this topic

[Mereel]

In one of the x-wing books (I think it was wraith squadron), an interdictor's gravity well generator was used to push the interdictor out of the way of another ship. How was this possible?

[Phoenix Rising]

In practice, gravity well projectors are not all that dissimilar to repulsorlift engines when using the former in reverse: both push against masses. That's why I've given interdictors extra maneuverability in PR in fact.

[Mereel]

In practice, gravity well projectors are not all that dissimilar to repulsorlift engines when using the former in reverse: both push against masses. That's why I've given interdictors extra maneuverability in PR in fact.

I just don't get how gravity pushes. Or are they not actually using gravity?

[Tropical Bob]

They're not specifically using gravity. What they do is simulate a mass shadow. Technically, it could be some sort of field that just interferes with FTL/trans-dimensional travel. Today's science isn't even completely sure how gravity is produced (Generally, it's accepted that mass produces gravity, but then again, there are theoretical particles called gravitrons or some such that could be the culprit.), so we really can't say what it can or can't do. Since gravity and dark energy are related in a way ("Pull" and "push," respectively), perhaps they are interchangeable (Such as mass and energy), and there's a neutral state in between them (Or an even mix would do the same trick of being neutral, I suppose.). So an interdictor could be a device that can transfer that "energy" between its different states.

The wonderful, and depressing, thing about science fiction is that you can make up any sort of futuristic device you want.

I personally think that they don't use gravity. Otherwise, interdictors probably wouldn't exist. Creating a planet-sized mass shadow with gravity would yield planet-strength gravity. A ship wouldn't likely survive being at the center. Plus, all that gravity would interfere with combat and fleet coordination.

Edited by Tropical Bob, 30 June 2009 - 09:49 PM.

[Phoenix Rising]

Well, let me preface this by saying that it's beyond our current observational understanding of gravity on Earth. Gravity, as we know it, is the "force" by which mass attracts - or, more accurately, the result of the curvature that mass places on spacetime. In theory, a negative mass - if such a thing should exist - would create a force that repulses. From Wiki:

Under general relativity, gravity is the result of following a geometry caused by local mass-energy. Although the equations cannot produce a "negative geometry" normally, it is possible to do so using a "negative mass". Interestingly, the same equations do not, of themselves, rule out the existence of negative mass.

Both general relativity and Newtonian gravity appear to predict that negative mass would produce a repulsive gravitational field.

(Spacetime curvature from normal, "positive" mass, signifying attraction. Negative mass would theoretically curve the other way, producing repulsion.)

I'm not a natural physicist though, so perhaps one of our resident experts could explain it better...

Edit: Thanks, Tropical Bob.

Edited by Phoenix Rising, 30 June 2009 - 09:59 PM.

[Phoenix Rising]

This is from a stats-mirroring site, but was summarized from the WEG sourcebooks:

The projectors emits waves of focused energy that disrupt mass lines in space, effectively simulating the presence of a true stellar body such as a asteroid or even a planet. Due to the size of the "gravity mass shadow", ships transversing through hyperspace drop back into realspace as their hyperdrive cutoffs activate when in proximity such to a "mass shadow". In fact hyperdrives cannot differentiate these artificial mass shadows from those created by stellar bodies. Occasionally, ships can suffer severe damage as a result. When suddenly pulled out of hyperspace, the ensnared ship's crew can be violently thrown about as they re-emerge in realspace. It is during this short window of confusion that Imperial vessels strike. Additionally, when a gravity well is placed within sufficient proximity of a vessel jumping into hyperspace is made virtually impossible. Due to sheer inertia it is impossible to quickly change the direction of the gravity wells' original movement, once they have been placed.

As interesting side note, once an Interdictor powers up all of its gravity well projectors, all nearby ships in realspace must adjust their inertial compensators to counter the effects on their ships' internal gravity. And more interesting still, if the gravity wells are reversed they push against nearby masses such as starships. Thus, permitting the Interdictor to quickly change its vector, far more quickly than its manoeuvring systems are capable. Such a manoeuvre however causes havoc for the ship's artificial gravity. Normally, the projectors cannot be set-up to conduct this tactic.

[Tropical Bob]

I'm not sure if I like that explanation. There shouldn't really be a way to "reverse" a gravity well projector. That'd be like trying to "reverse" a nuclear reactor. Even if it's possible to reverse the device, there would just be a completely opposite effect as when running it normally. All they'd be doing would be simulating a dark energy shadow. (Perhaps dark energy is just negative mass, so I guess you could also say negative mass shadow, or something along those lines.)

[Phoenix Rising]

Not sure how much is paraphrased and how much is straight from WEG; let me check the Imperial Sourcebook...

The gravity well generator works on a simple principle. When focused, it sends out waves of energy that disrupt mass lines in space, thereby simulating the presence of a large stellar body such as an asteroid or planetoid.

What exactly do they mean by "mass lines"? That it simulates a mass by warping spacetime?

[Vithar-133]

I do believe that by "mass lines", they mean a line that mass travels along. So, by disrupting this line, the gravity well generator can force ships out of hyperdrive.

[Tropical Bob]

It does sound like they mean space-time when they say "mass lines." (Aka, the grid in PR's picture.) The problem with assuming that it literally means lines that mass travels along is that mass can travel in any direction, leading to an infinite amount of lines. Might as well just say "mass space."

It could be that they emit gravitational waves. This would cause the space-time distortion needed to simulate a mass shadow, and wouldn't cause any gravitational problems that I can think of. I suppose if the waves are focused and powerful enough, they might be able to move the ship by warping space.

This also all depends on how hyperspace works. If it's trans-dimensional a la Slipspace in the Halo universe, disrupting space-time in realspace may do nothing.

[Phoenix Rising]

From what I understand, hyperspace is another dimension, along the lines of otherspace.

[Tropical Bob]

I think it's frequently mentioned as both trans-dimensional and plain FTL. That's why I'm unsure. The Wookiee page mentions this:

Normally, baryonic matter obeys physical principles of relativity: they increase exponentially in mass as they approach the speed of light, requiring more and more energy to approach it, and thus always remain below this threshold. Tachyonic matter, on the other hand, existed solely above the speed of light, and could not pass below said threshold. Hyperdrive technology allowed sentients to break this barrier and allowed slower-than-light starships to leap past the barrier and reach speeds many thousands or millions of times that of light.

Which leads me to believe that hyperspace is just a way of converting normal sub-luminal matter into super-luminal matter. Somehow. That would be normal FTL travel. I think I also remember tachyonic discharge from a fungus or something being used to track X-Wings through hyperspace to Eclipse Station during the Yuuzhan Vong War. That would be hard to accomplish in a separate dimension. Also, apparently if the hyperdrive cut-offs don't activate when entering a gravity well, a ship can smash into the said well, and explode. (Then again, that could go for trans-dimensional travel as well...)

But it's often mentioned as "entering hyperspace," "exiting hyperspace," and other variations of such. Which would have it tend more towards trans-dimensional travel.

The issue of the newer concept of Cronau Radiation also throws a wrench into what it could be. It could be radiation released when something crosses the light speed barrier, when normal matter is converted into tachyonic matter, or even when a hole is opened into hyperspace.

I personally think it'd be more natural for it to be a separate dimension. That would explain why space dust doesn't rip ships to shreds when they travel FTL. And why you're conscious during the FTL travel, since, if I remember correctly, you'd technically be energy once you pass the threshold of light speed.

And come to think of it, disrupting space-time could interfere with trans-dimensional travel. If realspace-time is warped under hyperspace-time, coordinates would begin to get muddled, the computer would detect fluctuations in dimensional positioning, and re-enter realspace to prevent danger.

Edited by Tropical Bob, 02 July 2009 - 05:23 AM.

[Phoenix Rising]

Hahaha, I uploaded that image onto Wookieepedia a few years ago . Good old SW:CCG.

I just want to make a few canonical points and maybe you can connect the astrophysical dots...

Presumably all hyperspace-capable ships were equipped with relativistic shields to prevent time dilation. I assume this would only be necessary if you were actually moving quite fast in hyperspace, if not going FTL.

Hyperwave transceivers, I believe, allowed communication between individuals in hyperspace and those in realspace. But how does a signal "exit" hyperspace?

As the Gravity Shadow card illustrates, mass in realspace projects a very real and deadly "shadow" onto hyperspace. If hyperspace is a distinct spatial dimension from realspace, why is this the case?

If, when in hyperspace, you are traveling at FTL, how can you see it? And just for the record, the appearance of hyperspace is more than just a filmmaking device such as sound in space (yes, I know it's simulated IU): I think it was Death Star that mentioned you could, according to rumor, go insane by staring into its swirling eddies.



Also in the same novel, it was said that the when the Death Star's superlaser shot Alderaan, it sent part of its mass into hyperspace. Wook also mentions that it "[ruptured] the barrier between this realspace and hyperspace". This would only be possible if hyperspace was, in fact, a distinct dimension.

Big question: is hyperspace simply the plane of existence for superluminal matter?

Edited by Phoenix Rising, 02 July 2009 - 07:57 AM.

[Phoenix Rising]

Yeah, Nil Spaar.

[Tropical Bob]

Presumably all hyperspace-capable ships were equipped with relativistic shields to prevent time dilation. I assume this would only be necessary if you were actually moving quite fast in hyperspace, if not going FTL.

Well, usually the advantages in traveling through an alternate dimension lying on top of realspace would be that the alternate dimension would be compressed over realspace. Kind of like thinking of the two dimensions as a trapezoid, with each layer comprised of the same number of points(Or a triangle if there are more of such dimensions layered even more.). The points will match up, but with less distance between the ones in the higher dimension, leading to much faster travel "in" realspace. Basically a wormhole effect, but utilizing a separate dimension to do so. The shielding would only be necessary if, as well as being ultra-compressed space-wise, the dimension had an ultra-compressed time-line. Another trapezoid/triangle when compared to realspace, if you will.

Normal FTL would have the noticeable problem of time dilation as well.

Hyperwave transceivers, I believe, allowed communication between individuals in hyperspace and those in realspace. But how does a signal "exit" hyperspace?

Well it could be that the signal never "exits," but somehow "echoes" around the hyperspace dimension, and the receivers are able to either pick up these "echoes," or can somehow dip itself into hyperspace dimension in order to communicate.

If it was FTL travel, the signal could probably be "forced" to go FTL somehow, maybe by piggybacking on some other super-luminal entity. Likewise, releasing an STL signal may "force" it out of FTL travel.

As the Gravity Shadow card illustrates, mass in realspace projects a very real and deadly "shadow" onto hyperspace. If hyperspace is a distinct spatial dimension from realspace, why is this the case?

If hyperspace is an ultra-compressed layer on top of realspace, perhaps when realspace-time begins to warp and compress beneath hyperspace-time from a large mass in realspace, the hyperspace just become too compressed or warped for the vessel to handle, forcing it back into realspace, and into the looming gravity well and/or immediate uncontrolled expansion of the vessel back into realspace.

It could also be that if the dimensions are layered, mass does project shadows on other dimensions.

FTL, obviously, would exist in the same dimension.

If, when in hyperspace, you are traveling at FTL, how can you see it? And just for the record, the appearance of hyperspace is more than just a filmmaking device such as sound in space (yes, I know it's simulated IU): I think it was Death Star that mentioned you could, according to rumor, go insane by staring into its swirling eddies.

If space is just compressed in hyperspace, and you move normal speeds, you would be able to see whatever is there.

If you move FTL while going through hyperspace, or in realspace, you'd still be receiving light from a certain arc ahead of the vessel. Perhaps when going FTL, there is a certain effect around the vessel. Maybe it's Cronau Radiation building up in a bubble around the vessel that bursts when reverting to realspace.

Also in the same novel, it was said that the when the Death Star's superlaser shot Alderaan, it sent part of its mass into hyperspace. Wook also mentions that it "[ruptured] the barrier between this realspace and hyperspace". This would only be possible if hyperspace was, in fact, a distinct dimension.

The same thing happened when the Death Star II exploded, apparently. Some of its wreckage was found on Mon Calamari, along with Vader's glove, if you think those books are relatively canonical.

Big question: is hyperspace simply the plane of existence for superluminal matter?

Until we get the word from Lucas-peoples, we can only theorize.

Oh, and for all who read my stuff, I'm not really an expert. I'm just piecing together what I do know (Which isn't really that much), and running onwards from there.