Relativity

Jonathan_S wrote: Flag in Exile, when talking about ballistic attacks on Grayson's forts / stations (should Honor hold the GSN back under their protection) we got this nugget - "if the Peeps launched at .8 c, their birds' drives would boost them to .99 c before burnout."

Though this bugs me because that's too high a velocity if you suddenly start making missiles follow relativistic acceleration formula; but it's an unnecessarily high ship speed if missiles continue to seemingly ignore relativity impact on speed and acceleration.

If you stick with the way missiles have seemed to work elsewhere in the books you'd only need to get the launch ship up to about .72c for the missile to burnout at .99c. Why would Honor think the Peeps would spend the extra 2 hours boosting a Triumphant-class BB the extra unnecessary 0.8c just to fire a missile for less than its full drive endurance?

(As a sanity check I also looked at whether RFC might have been thinking a full power missile accel, but that only gets burnout to .98c; plus I don't see why for a ballistic shot you'd ever spend more time at the low ship acceleration to let you skip the extra six minutes of the vastly higher missile acceleraiton)

ThinksMarkedly wrote:

cthia wrote:Somewhere over in the thread, the .8c rad-shield limitation imposed on a missile's accel is the impetus behind my conception of a MAN missile using a different design which allows it to use 100% of its missile's accel.

That sentence makes no physical sense. The 0.8 or 0.9c limitation of the particle shields applies to top speed, not accel. It doesn't matter how fast you get to that speed, you can't pass it.

Jonaghan_S wrote:Plus the 0.8c limit is on rad shielding in ships to protect humans. Missiles already exceed that. Even as far back a Flag in Exile, when talking about ballistic attacks on Grayson's forts / stations (should Honor hold the GSN back under their protection) we got this nugget - "if the Peeps launched at .8 c, their birds' drives would boost them to .99 c before burnout." There was no indication that the missiles couldn't do that, or that their laserheads would be non-function when they reached attack range. (They definitely wouldn't be going for kinetic kills; not with the planet Grayson floating behind most of the targets)

That missile velocity is obviously far easier to reach with a MDM since you don't need anywhere near as much base velocity from the launching ship for the missile to exceed 0.8c. (Heck, in theory an MDM could do so from a standing start; but only in the last several seconds before 3rd stage burnout -- so in practice it's only likely to exceed that if the ship has build up some noticeable velocity before launch)

Both of you are missing my point, although you touched on an element of it Jonathan. A standing start.

One of the drawbacks an LD has from being able to get so close to the enemy, is even if it deployed racks of conventional missiles to light off when it is long gone, the speed of the missile on its attack run would be too low, thus easily picked off.

I'm proposing a missile that can reach the top speed of .9c quickly, from an LDs low engagement range. Resulting in a missile still coming in at .9c from an LD's impossibly close engagement range.

My Porsche 911 had a governor limited top speed, but I could reach that top speed much faster and in a much shorter distance than the average car. It had gobs of passing speed.

Suddenly I see why people hate Manticore. They always win. And nobody can have better tech. Even when the MA's stealth is obviously better, many are still in denial. If someone in the forum would have posited an enemy with the MA's tech before it was introduced, it would have been impossible. Although GA missiles also achieve the impossible.

Oh, and yes, per your post a click or so upstream Jonathan, there is still a little room for more top speed. What's ignoring relativistic effects a bit more and coming even closer to c? The difference is what Navy gets an allocation of handwavium?

cthia wrote:Both of you are missing my point, although you touched on an element of it Jonathan. A standing start.

One of the drawbacks an LD has from being able to get so close to the enemy, is even if it deployed racks of conventional missiles to light off when it is long gone, the speed of the missile on its attack run would be too low, thus easily picked off.

I'm proposing a missile that can reach the top speed of .9c quickly, from an LDs low engagement range. Resulting in a missile still coming in at .9c from an LD's impossibly close engagement range.

My Porsche 911 had a governor limited top speed, but I could reach that top speed much faster and in a much shorter distance than the average car. It had gobs of passing speed.

Suddenly I see why people hate Manticore. They always win. And nobody can have better tech. Even when the MA's stealth is obviously better, many are still in denial. If someone in the forum would have posited an enemy with the MA's tech before it was introduced, it would have been impossible. Although GA missiles also achieve the impossible.

Oh, and yes, per your post a click or so upstream Jonathan, there is still a little room for more top speed. What's ignoring relativistic effects a bit more and coming even closer to c? The difference is what Navy gets an allocation of handwavium?

Getting to top speed as quickly as possible is pretty much the goal of all missiles, with the secondary goal of still having power to maneuver to hit the target. Everyone would do this if they could, but the universe doesn't work that way.

Theemile wrote:

cthia wrote:Both of you are missing my point, although you touched on an element of it Jonathan. A standing start.

One of the drawbacks an LD has from being able to get so close to the enemy, is even if it deployed racks of conventional missiles to light off when it is long gone, the speed of the missile on its attack run would be too low, thus easily picked off.

I'm proposing a missile that can reach the top speed of .9c quickly, from an LDs low engagement range. Resulting in a missile still coming in at .9c from an LD's impossibly close engagement range.

My Porsche 911 had a governor limited top speed, but I could reach that top speed much faster and in a much shorter distance than the average car. It had gobs of passing speed.

Suddenly I see why people hate Manticore. They always win. And nobody can have better tech. Even when the MA's stealth is obviously better, many are still in denial. If someone in the forum would have posited an enemy with the MA's tech before it was introduced, it would have been impossible. Although GA missiles also achieve the impossible.

Oh, and yes, per your post a click or so upstream Jonathan, there is still a little room for more top speed. What's ignoring relativistic effects a bit more and coming even closer to c? The difference is what Navy gets an allocation of handwavium?

Getting to top speed as quickly as possible is pretty much the goal of all missiles, with the secondary goal of still having power to maneuver to hit the target. Everyone would do this if they could, but the universe doesn't work that way.

Nobody else had the motivation to do so because they are engaging from across the horizon. The MA engages from just outside your front yard.

Much shorter engagement ranges should allow much faster accelerations still leaving plenty for attack runs.

cthia wrote:

theemile wrote:Getting to top speed as quickly as possible is pretty much the goal of all missiles, with the secondary goal of still having power to maneuver to hit the target. Everyone would do this if they could, but the universe doesn't work that way.

Nobody else had the motivation to do so because they are engaging from across the horizon. The MA engages from just outside your front yard.

Much shorter engagement ranges should allow much faster accelerations still leaving plenty for attack runs.

What do you mean "no one had the motivation" - such a technology would be advantageous to anyone. Everyone has been trying to push their missiles, faster, and longer, and the technology tree has been a slow, linear climb.

So how do you propose to do this? Everyone to date has tried, but been limited by their missile technology, namely node burnout and power storage. A node can only be made so powerful and run for so long. Make it more powerful, with a higher accel, and it burns out quicker. And capacitors - they can only hold so much for a given volume. This is the reason single drive missiles had 2 accels, one was for quick snapshots to get as much velocity as quickly a possible in short range, the other was a lower accel over a longer time to have longer drive reach and higher end run velocities.

They may want something, or it may be advantageous to them, but that does not mean it is possible to have.

Theemile wrote:Getting to top speed as quickly as possible is pretty much the goal of all missiles, with the secondary goal of still having power to maneuver to hit the target. Everyone would do this if they could, but the universe doesn't work that way.

cthia wrote:Nobody else had the motivation to do so because they are engaging from across the horizon. The MA engages from just outside your front yard.

Much shorter engagement ranges should allow much faster accelerations still leaving plenty for attack runs.

Theemile wrote:What do you mean "no one had the motivation" - such a technology would be advantageous to anyone. Everyone has been trying to push their missiles, faster, and longer, and the technology tree has been a slow, linear climb.

So how do you propose to do this? Everyone to date has tried, but been limited by their missile technology, namely node burnout and power storage. A node can only be made so powerful and run for so long. Make it more powerful, with a higher accel, and it burns out quicker. And capacitors - they can only hold so much for a given volume. This is the reason single drive missiles had 2 accels, one was for quick snapshots to get as much velocity as quickly a possible in short range, the other was a lower accel over a longer time to have longer drive reach and higher end run velocities.

They may want something, or it may be advantageous to them, but that does not mean it is possible to have.

Perhaps he already answered your question.

cthia wrote:The difference is what Navy gets an allocation of handwavium?

cthia wrote:Both of you are missing my point, although you touched on an element of it Jonathan. A standing start.

One of the drawbacks an LD has from being able to get so close to the enemy, is even if it deployed racks of conventional missiles to light off when it is long gone, the speed of the missile on its attack run would be too low, thus easily picked off.

Indeed.

I'm proposing a missile that can reach the top speed of .9c quickly, from an LDs low engagement range. Resulting in a missile still coming in at .9c from an LD's impossibly close engagement range.

I don't think you've done the math on this.

For a missile to go from a standing start to 0.9c in 3 minutes (a three 60-second stage full power burn), discounting the subject of this thread, it needs to accelerate at 152,000 gravities and will cover just over 8 million km. That's close enough a value for existing technology to achieve in a reasonable time frame, but 3 minutes is long enough for every single ship to bring up their sidewalls, acquire locks, interpose wedges, launch wave after wave of CMs, and for the Combat Space Patrol LACs to position themselves for an intercept. Remember BC and above RMN ships can defend themselves with interposed wedges due to Keyhole.

To do the same in 60 seconds, it needs to go to 458,000 gravities. If current burn-out rates are linear (1/3rd the time is 2x the acceleration), the MAlign would need a 1.5x improvement in impellers over current state of the art. Doable, but starts to become unlike. And 60 seconds is still plenty of time for sidewalls, full action stations, and a partial rotation to interpose the wedge.

Anything above 450,000 gravities is stretching the imagination. The MAlign has not been researching impeller improvements that deeply, as far as we know. We'd have seen some bigger breakthrough in the Cataphracts than we've seen so far, for example.

A million gravities in the next 10 T-years is ludicrous. They might as well go to plaid.

BTW, given that RMN ships can fire and defend themselves with interposed wedges, they should always maintain with wedges perpendicular to the ecliptic (picture a TIE fighter). The acceleration vector perpendicular to the line where the wedges' extensions meet astern of the ship, so the ship does not have much reason to keep the open aspects to the plane of the ecliptic. The Ghost Riders should provide plenty of information, even if Keyhole is not deployed.

My Porsche 911 had a governor limited top speed, but I could reach that top speed much faster and in a much shorter distance than the average car. It had gobs of passing speed.

The analogy is not a good one. You're not really comparing how fast a regular street car and a Porsche 911 can accelerate to each other. That's about a 3x to 4x increase (quick Google search shows a Porsche 911 can do 0-100 km/h in 2.6 seconds, which is just under 4x for compared to a "tame" 10 seconds). Your proposal is well past 10x and there's nothing that can do it under 1 second, not even a Formula 1 with a fully charged MGU-K.

Suddenly I see why people hate Manticore. They always win. And nobody can have better tech. Even when the MA's stealth is obviously better, many are still in denial. If someone in the forum would have posited an enemy with the MA's tech before it was introduced, it would have been impossible. Although GA missiles also achieve the impossible.

You have to posit a plausible scenario by which the technology breakthrough happened. RFC has been very careful in extending the technology in such a way it is believable and builds upon previous hints. The spider drive and the MDM are so far the only that aren't Black Swans (i.e., you can't simply say it's a logical extension of where the state of the art was). The streak drive was explained as pure brute force and we know hyperspace bands had been cracked 7 times before in the past.

I'm not saying a missile accelerating at 2 million gravities is impossible. As far as we know, there is no limit to how fast an impeller wedge could accelerate an object. But a 10x improvement on a very mature technology in less than one decade defies belief. If we're going to start imagining implausible weapons, why not a particle or graser beam that keeps coherency up to 10 million km? Or an FTL missile? Or maybe make TWTSNBN work over long distances?

Oh, and yes, per your post a click or so upstream Jonathan, there is still a little room for more top speed. What's ignoring relativistic effects a bit more and coming even closer to c? The difference is what Navy gets an allocation of handwavium?

I suspect the 0.8 and 0.9 particle shield limits exist so that RFC does not have to keep a hyperbolic motion calculator at hand. Though I'd be glad to give him a spreadsheet with the formulae, at least for linear motion (2D gets way too difficult).

In-universe, even missiles have a top speed. Interplanetary space is not empty, it's full of light and matter. As you approach the speed of light, said dust will abrade your missile considerably, not to mention the kinetic energy of the impact of them is terrifying (see discussion with Loren).

I never said it is probable because the series is biased in favor of the SK. But it is certainly possible. I've always favored the old maxim "If you can conceive it, then you can achieve it."

No other Navy really had the motivation as the MA does. They can get close enough to read the fake designer label on your undies. Remember, FTL was once laying around in a Cold Case file.

Please forgive me for pretending I have a literary license to shorten your name on occasion to TM. My most humble apology and an assurance of no intended disrespect.

ThinksMarkedly wrote:
I don't think you've done the math on this.

No need to think. I can assure you I don't allow my slipstick within a parsec of a sci-fi novel.

ThinksMarkedly wrote:For a missile to go from a standing start to 0.9c in 3 minutes (a three 60-second stage full power burn), discounting the subject of this thread, it needs to accelerate at 152,000 gravities and will cover just over 8 million km. That's close enough a value for existing technology to achieve in a reasonable time frame, but 3 minutes is long enough for every single ship to bring up their sidewalls, acquire locks, interpose wedges, launch wave after wave of CMs, and for the Combat Space Patrol LACs to position themselves for an intercept. Remember BC and above RMN ships can defend themselves with interposed wedges due to Keyhole.

To do the same in 60 seconds, it needs to go to 458,000 gravities. If current burn-out rates are linear (1/3rd the time is 2x the acceleration), the MAlign would need a 1.5x improvement in impellers over current state of the art. Doable, but starts to become unlike. And 60 seconds is still plenty of time for sidewalls, full action stations, and a partial rotation to interpose the wedge.

Are you sure about that? You seem to be attributing superhuman abilities to humans and technology. You are telling me that a fleet or ship that is completely oblivious to an attack in a total time of peace, a fleet that is sharing birthday cake of one of the officers, can suddenly shake off their shock, launch LACs and the LACs can get into position, and the XO can give orders to the helmsman (because the Captain is in her quarters) and the helmsman can react and the ship can respond all in three minutes? The human brain needs time to process the impossible, the improbable and the unlikely. See Chin in At All Costs. Assuming!...the wedges are magically even up anticipating a sucker punch! On top of that, are you absolutely certain software can cope with these, insane, acceleration rates???

ThinksMarkedly wrote:Anything above 450,000 gravities is stretching the imagination. The MAlign has not been researching impeller improvements that deeply, as far as we know. We'd have seen some bigger breakthrough in the Cataphracts than we've seen so far, for example.

At least not onscreen, so thanks for adding the qualifier, "as far as we know." Cataphracts would not represent the state of the art MAlign design. No Navy wants to serve any wine before it's time.

TM wrote:A million gravities in the next 10 T-years is ludicrous. They might as well go to plaid.

So sayeth every Solarian from the Sol system to the Haven sector and all points in-between regarding RMN tech until they were killed by...plaid.

TM wrote:BTW, given that RMN ships can fire and defend themselves with interposed wedges, they should always maintain with wedges perpendicular to the ecliptic (picture a TIE fighter). The acceleration vector perpendicular to the line where the wedges' extensions meet astern of the ship, so the ship does not have much reason to keep the open aspects to the plane of the ecliptic. The Ghost Riders should provide plenty of information, even if Keyhole is not deployed.

Uh huh, after they can bring the wedge up. As I understand it a three minutes sucker punch ain't gonna given sitting ducks enough time. Byng would be proud.

My Porsche 911 had a governor limited top speed, but I could reach that top speed much faster and in a much shorter distance than the average car. It had gobs of passing speed.

TM wrote:The analogy is not a good one. You're not really comparing how fast a regular street car and a Porsche 911 can accelerate to each other. That's about a 3x to 4x increase (quick Google search shows a Porsche 911 can do 0-100 km/h in 2.6 seconds, which is just under 4x for compared to a "tame" 10 seconds). Your proposal is well past 10x and there's nothing that can do it under 1 second, not even a Formula 1 with a fully charged MGU-K.

I wasn't going for a perfect analogy. Again, someone is missing the forest for the analogy. The analogy did what it was designed to do. It put you in the ballpark of what I am proposing. Instead of your trite dismissal of it as nonsense.

Suddenly I see why people hate Manticore. They always win. And nobody can have better tech. Even when the MA's stealth is obviously better, many are still in denial. If someone in the forum would have posited an enemy with the MA's tech before it was introduced, it would have been impossible. Although GA missiles also achieve the impossible.

ThinksMarkedly wrote:You have to posit a plausible scenario by which the technology breakthrough happened. RFC has been very careful in extending the technology in such a way it is believable and builds upon previous hints. The spider drive and the MDM are so far the only that aren't Black Swans (i.e., you can't simply say it's a logical extension of where the state of the art was). The streak drive was explained as pure brute force and we know hyperspace bands had been cracked 7 times before in the past.

True, I can't say it is a logical extension of RMN tech. I can say it would be a consistent habit of the MA to think outside the box. And, having their location classified, not operating on a time schedule while fighting for its life, able to work on tech sporadically for centuries allows them to accomplish what the average Navy doesn't have time to do. Even if that other Navy has the motivation or insight. We're talking Alphas, baby.

ThinksMarkedly wrote:I'm not saying a missile accelerating at 2 million gravities is impossible.

As long as we got that straight, I consider it a home run.

TM wrote:As far as we know, there is no limit to how fast an impeller wedge could accelerate an object. But a 10x improvement on a very mature technology in less than one decade defies belief. If we're going to start imagining implausible weapons, why not a particle or graser beam that keeps coherency up to 10 million km? Or an FTL missile? Or maybe make TWTSNBN work over long distances?

Implausible weapons, so sayeth that same, perhaps, soon to be enlightened Solarian. As far as the rest - except for Voldemort, because he ruffles the author's feathers - why not? I wouldn't put anything past the dynamic duo during peace.

Oh, and yes, per your post a click or so upstream Jonathan, there is still a little room for more top speed. What's ignoring relativistic effects a bit more and coming even closer to c? The difference is what Navy gets an allocation of handwavium?

TM wrote:I suspect the 0.8 and 0.9 particle shield limits exist so that RFC does not have to keep a hyperbolic motion calculator at hand. Though I'd be glad to give him a spreadsheet with the formulae, at least for linear motion (2D gets way too difficult).

In-universe, even missiles have a top speed. Interplanetary space is not empty, it's full of light and matter. As you approach the speed of light, said dust will abrade your missile considerably, not to mention the kinetic energy of the impact of them is terrifying (see discussion with Loren).

Agreed, but those limitations were reached long ago. See my sentiments of missiles operating in a veritable minefield of debris in the aptly named thread. But somehow matter has never seemed to...matter.

I almost forgot. Shorter engagement ranges means the impellers do not have to hold up as long.

Comparing a 911 to a sedan is not the right comparison. Compare the 0 to mach 1.5 of your 911 and an f18 off a carrier catapult.