?

ThinksMarkedly wrote:My assumption was that the missile sustained the same acceleration for the 9 minutes of its own perceived time, including dilation.

Do you have to include the time from launch to when the missile achieves a high enough speed for the Lorentz equations become more than just a consumer of computer cycles? Or are you assuming the launch platform going at least the .3c required for relativisitic effects to be become significant?

Fox2! wrote:

ThinksMarkedly wrote:My assumption was that the missile sustained the same acceleration for the 9 minutes of its own perceived time, including dilation.

Do you have to include the time from launch to when the missile achieves a high enough speed for the Lorentz equations become more than just a consumer of computer cycles? Or are you assuming the launch platform going at least the .3c required for relativisitic effects to be become significant?

Doesn't make a difference in the equations. You don't need to compute instant by instant, since those equations are solved already (I quoted them in the thread above). Source: https://en.wikipedia.org/wiki/Hyperbolic_motion_(relativity)

The delta in speed is relative to the launch velocity. So if the ship did not accelerate or decelerate since launching, it should measure the missile at 0.671c at the end of its run, regardless. If it's accelerating or decelerating, that's another story, but a DD at 720 G will only change its velocity by 0.014c in the 601.4s until the missile burns out. Approximately, because then the time dilation effects will also change the lifetime of the missile.

Here are a couple of simulations where the launching vessel has velocity relative to an observer (like the target):

At rest

• Duration: 601.4 s (0:10:01.4)
• Range: 69.47 million km (3.86 light-minutes)
• Final speed: 0.671c
• Launching vessel covers: 0 km (69.47 million km behind)

0.1c

• Duration: 624.5 s (0:10:24.5)
• Range: 78.17 Gm (4.35 lm)
• Final speed: 0.723c
• Launching vessel covers: 18.72 Gm (59.45 Gm behind)

0.2c

• Duration: 648.2 s (0:10:48.2)
• Range: 88.30 Gm (4.91 lm)
• Final speed: 0.786c
• Launching vessel covers: 38.86 Gm (49.44 Gm behind)

0.3c

• Duration: 674.0 s (0:11:14.0)
• Range: 100.25 Gm (5.57 lm)
• Final speed: 0.808 c
• Launching vessel covers: 60.62 Gm (39.63 Gm behind)

0.6c

• Duration: 793.5 s (0:13:13.5)
• Range: 156.09.61 Gm (8.68 lm)
• Final speed: 0.906c <== particle shield failure likely
• Launching vessel covers: 142.74 Gm (13.35 Gm behind)

cthia wrote:I'm pointing out the similarity of the overarching concept, not method.

This is what Wikipedia states about the MHD drive:

Few large-scale working prototypes have been built, as marine MHD propulsion remains impractical due to its low efficiency, limited by the low electrical conductivity of seawater. Increasing current density is limited by Joule heating and water electrolysis in the vicinity of electrodes, and increasing the magnetic field strength is limited by the cost, size and weight (as well as technological limitations) of electromagnets and the power available to feed them.

ThinksMarkedly wrote:

Jonathan_S wrote:[1] We're told an MDM can pull 46,000 gees for 9 minutes, giving it a range from rest of about 65 million km, and a burnout velocity around .8c. Newton agrees.
But ask Lorentz and those numbers give you the far different answers of about 31 million km and .37c. That's be a hell of a rounding difference

That depends on the parameters you input into the calculation. In the "MDMs should last a little longer than they do" thread I started, I used a different assumption. Since posting that, I've found other people had made the same calculations years before, but I don't recall the thread name now to find the post.

My assumption was that the missile sustained the same acceleration for the 9 minutes of its own perceived time, including dilation. For the launching ship, assuming it did not accelerate or decelerate since launching, we'd have:

Newtonian:

• Duration: 540 s
• Range: 65 771 240.2 km (ΔS = (at²)/2)
• Final speed: 243 597 186 m/s ≅ 0.812c (Δv = at)

Relativity:

• Duration: 601.4 s [T = c/a sinh(aτ/c)]
• Range: 69 470 572.1 km [ΔS = c²/a (cosh(aτ/c) - 1)]
• Final speed: 201 159 563 m/s ≅ 0.671c [Δv = c tanh(aτ/c)]

It achieves a lower overall velocity, but because it lasts 11.4% longer, it actually travels further.

Fair enough - I was in a hurry and didn't bother to work out the time from various perspectives.

Though for what it's worth there are a few spots in the books where a missile salvo's time to impact is given and those seems to show the 9 minute burn time is via the ship's clocks; not the missile's.
So we're still left with a lot of statements in the books about missile performance and elapsed time that simply don't line up with any perspective that takes relativity into account.
(Also no mention of the laser or radio control links having to deal with some pretty noticeable Doppler shift effects in their frequencies)

Jonathan_S wrote:Though for what it's worth there are a few spots in the books where a missile salvo's time to impact is given and those seems to show the 9 minute burn time is via the ship's clocks; not the missile's.

Indeed. That's why the thread was "MDMs should last a little longer than they do".

So we're still left with a lot of statements in the books about missile performance and elapsed time that simply don't line up with any perspective that takes relativity into account.
(Also no mention of the laser or radio control links having to deal with some pretty noticeable Doppler shift effects in their frequencies)

That's easily compensated. It was probably fixed after the first missile fired and lost telemetry.

"What happened?" asked the supervising CO, the first to say anything after the tiny explosion was noted on the displays. Looking around the control room, all she could see were blank and dejected faces of his team. Everyone clearly had high hopes for the Ghost Rider Project, that it would be a silver bullet and end the war with the Peeps once and for all without exposing Manticoran spacer lives to more risk. He was also acutely aware that Rear Admiral of the Red Sonja Hemphill, was in the observation gallery above the control centre, looking over his shoulder. Actually, she was probably on her way down to the control centre right now and would be coming in through the door any second to demand to know what had happened. "Did the missile malfunction?"

"I don't know, sir. I'm looking over the telemetry right now and I can't see anything wrong, up until the moment the telemetry stops" replied Petty Officer Second Class Jason Wilkins. The technician by Jason's side, PO Third Class Alonzo Gomez, was furiously scrolling through the data and was opening and closing his mouth, but making no sounds. "Everything looks exactly like it should have looked! The second stage lit up as expected, there was no variance in the node alignment, so it looks like the baffles worked..."

"What happened?" demanded a voice from the hatch, that was still opening. Sonja Hemphill, current heiress to the Barony of Low Delhi and director of Project Gram, was pushing through and moving towards the central telemetry screens.

"We don't know yet, ma'am," replied the CO. "We're looking at the telemetry, but everything looks fine in what we received. You can see that for yourself." She pointed to the scrolling columns of numbers and the graphs on the big display on the wall. They all cut abruptly close to the right edge of the display.

"Everything looks right," Hemphill said, echoing what PO2 Wilkins had said moments before. "Doesn't look like any component failed, or at least gave any indication it was about to fail. No significant variances from projections."

It was at this point that PO Wilkins noticed that PO Gomez had stopped scrolling through the data and stopped opening his mouth. He was just staring at one particular screen, with a frown on his forehead. He was looking at the telemetry link data. Not the data that the telemetry was providing, but at the information about the telemetry itself. "Metadata" was the page title. And it was showing the exact point where the telemetry link cut, a series of error codes indicating why the link was cut. It ended in "lost carrier signal," but before that the computer was already accusing multiple failures to decode the signal.

"Dude, the frequency," Gomez finally managed to whisper. Wilkins' eyes quickly moved towards that column of data, almost involuntarily. He'd been trained, again and again, to respond to officer requests for the most unimportant minutia of detail at a moment's notice. Locating anything was second nature to him. They were always asking for things that he had no clue why they wanted to know. Especially Adm. Hemphill. Whenever she was present, she seemed to go out of her way to ask for things no one ever expected her to ask. She was always drilling them, though neither Wilkins nor Gomez knew what they were being drilled for. It's not like there was going to be an emergency in the middle of the Unicorn Belt in the Manticore-B system, which was closed to all foreign traffic. And she always looked busy after asking or the data, almost as if she needed it for something. No, far more likely, she was just checking her own readings to make sure they had answered correctly. But anyway, at this point, he could find the telemetry link frequency data faster than he could remember his parents' contact details. "The frequency..."

Wilkins frowned too. The data showed that the link dropped because the frequency went outside the range the receiver could effectively receive. It was a wide range, because as missiles accelerated away from the launching platform, the oscillations in the electromagnetic spectrum that served as telemetry became further and further apart. This was known since before humanity had ever left its home planet. In fact, the effect was known since before electromagnetic waves were even theorised. as it applied to sound waves too. Just stand near a street and you'll hear the sound an air or ground car makes change its pitch as it passed by you. The name was even reused from the original name as applied to sound waves.

But this signal went right up to the edge of what this receiver was calibrated for. The myriad of decoding errors in the previous screen were likely caused by the signal nearing the edge of receptivity. And then when it when over the edge completely, the receiver lost the lock and gave up. And it was just their bad luck that the signal cut shortly before the missile detonated. Could the two facts be linked?, wondered Wilkins.

"Huhhh", Wilkins wondered aloud, as he calculated the precise moment the missile detonated. Fortunately, this was easy since they had multiple recon drones along the trajectory of the missile. What he came up with stunned him.

"The missile exploded at the exact moment we lost telemetry" someone said. Wilkins thought that was him, since that's exactly what he was thinking, but then it registered that the voice was feminine. And it had come from over his shoulder, not his mouth. He looked up and noticed that Adm. Hemphill was standing there, looking at his screen. She must have come over when he muttered aloud, drawing attention to him and Gomez. "If we lost the link, the missile lost the link too, since it has the same type of transceiver array. And if it lost the link, it aborted."

A wave of relief washed over Wilkins. If the missile aborted, it wasn't a component failure. The missile simply destroyed itself to avoid falling into the wrong hands. Whose hands would be wrong in the Manticore-B system, he didn't know. He was only a Petty Officer Second Class, whose ambitions never went above making Chief and excelling in his domain, and no one told him these things.

"The frequency..." Gomez muttered for the third time. The young man seemed to be catatonic. He was definitely oblivious to the person wearing admiral stripes on the other side. Wilkins elbowed Gomez to see if he'd snap out of it, but it was too late. Adm. Hemphill, known by some, including all the enlisted crew in the command centre, as "Horrible Hemphill" had zeroed in on him. She had that look too, the one she gave when you displeased her, usually by breaking her concentration. And then it changed.

"The frequency!" she exclaimed. Her face went from annoyance, to realisation, to frustration, then back to annoyance. "The frequency is way too red-shifted. Did we account for the Doppler Effect?" she asked. As enlisted crew, both Wilkins and Gomez wisely kept their mouths shut. Moment later, Hemphill left to confer with the CO and other officers, relieving them of the need to answer. But not the need to know.

"Dude, did we account for the Doppler Effect?" Wilkins asked Gomez in a low voice. Gomez looked back and had an ashen face. He shook his head.

"Dude, I don't think so..." Gomez replied.

"Dude..." Wilkins agreed.

tlb wrote:Poker and other games can teach you strategy, but they will not teach you tactics; but then chess does not teach military tactics either.

Chess is nothing BUT a collection of military tactics.

Haven tried a tactic the MA may succeed in . . .

- Blitzkrieg, Fool's Mate = A short victorious war.

Then there's . . .

- Pincer movement. Used many times in the series. King under attack by both Knights.

- Ambush. Used many times in the series. The tactic killed Courvosier. And tore Honor a new heine. Ever got setup by a Knight?

- A Flying wedge - You might have seen this used against you, if your opponent knew how to use his pawns effectively. This would be the wall that capital ships form.

- Raiding - Sending your Queen behind enemy lines to do as Honor does. Cut Throat.

- Echelon formation - Honor and the RMN uses this to position it's warships. Entire books are written on the subject in chess.

- Pinning a piece. Pinning a force against the planet.

- Mutual support. Combination moves in chess.

- Interdiction = Preventing Castling.

- Stealth = Positioning a bishop behind another piece whose influence becomes devastating after that piece is moved. A one-two punch. Advanced.

I could go on. And on.

cthia wrote:Chess is nothing BUT a collection of military tactics.

Even if I accepted that Chess moves were a good approximation of military moves, it remains true that chess pieces do not have to be recruited, trained, equipped, fed, motivated and led; all of which require qualities that are not needed by chess. The remarks about resources and the quote from George Eliot are key and so far your only comment is that it reminds you of playing chess with a two year old (which you also slipped into something you quoted from me).

To repeat: General Lee probably had a better intellect than that of General Grant, but it was Grant that continually prevailed over him (except at Cold Harbor) and won in the end.

From chapter 34 of Flag in Exile:

"But—" Bagwell started, then drew a deep breath. "My Lady, I understand your logic, but we don't have the firepower for it. Not anymore."
"I think we can at least cripple their battleship element," Honor replied in that same soft voice. "We can do enough damage to make it unlikely they'll take on the light forces we have left here and in Endicott."
"And while we're doing that, My Lady," Bagwell said very, very quietly, "they'll completely destroy this squadron."
Honor regarded him for a moment. The fussy, detail-minded ops officer looked back without personal fear, but she understood the deeper fear in his eyes. More than that, she knew he was right. But sometimes the price which had to be paid was just as fearsome as the people who had to pay it feared it would be, she thought, and held his gaze for another ten seconds, then lowered her eyes to her com screen to Terrible's bridge.
"Captain Yu," she asked with a small, tired smile, "do you concur with Commander Bagwell's analysis?"
"Yes, My Lady, I do," Yu said, meeting her gaze levelly.
"I see. Tell me, Alfredo, did you ever read Clauzewitz?"
"On War, My Lady?" Yu sounded surprised. She nodded, and he frowned for an instant, then nodded back. "Yes, My Lady, I have."
"Then perhaps you remember the passage in which he said 'War is fought by human beings'?"
He gazed at her for another long moment, his eyes almost as opaque as they'd been the day she discovered he was her new flag captain, and then he nodded a second time.
"Yes, My Lady, I do," he said in a rather different tone.
"Well, it's time to find out if he's still right, Captain. As soon as Commander Sewell has that course for you, get us moving along it."

At this point both sides had analyzed the situation and come to the same conclusions: if Honor's force fought Theisman's force, then both would be battered but the Haven side would likely win. The difference was that Honor was prepared to die to give her side a chance to win, while Theisman was not prepared to die if his side had a chance to lose. Better to live to fight another day.

tlb wrote:

cthia wrote:Chess is nothing BUT a collection of military tactics.

Even if I accepted that Chess moves were a good approximation of military moves, it remains true that chess pieces do not have to be recruited, trained, equipped, fed, motivated and led; all of which require qualities that are not needed by chess. The remarks about resources and the quote from George Eliot are key and so far your only comment is that it reminds you of playing chess with a two year old (which you also slipped into something you quoted from me).

To repeat: General Lee probably had a better intellect than that of General Grant, but it was Grant that continually prevailed over him (except at Cold Harbor) and won in the end.

From chapter 34 of Flag in Exile:

"But—" Bagwell started, then drew a deep breath. "My Lady, I understand your logic, but we don't have the firepower for it. Not anymore."
"I think we can at least cripple their battleship element," Honor replied in that same soft voice. "We can do enough damage to make it unlikely they'll take on the light forces we have left here and in Endicott."
"And while we're doing that, My Lady," Bagwell said very, very quietly, "they'll completely destroy this squadron."
Honor regarded him for a moment. The fussy, detail-minded ops officer looked back without personal fear, but she understood the deeper fear in his eyes. More than that, she knew he was right. But sometimes the price which had to be paid was just as fearsome as the people who had to pay it feared it would be, she thought, and held his gaze for another ten seconds, then lowered her eyes to her com screen to Terrible's bridge.
"Captain Yu," she asked with a small, tired smile, "do you concur with Commander Bagwell's analysis?"
"Yes, My Lady, I do," Yu said, meeting her gaze levelly.
"I see. Tell me, Alfredo, did you ever read Clauzewitz?"
"On War, My Lady?" Yu sounded surprised. She nodded, and he frowned for an instant, then nodded back. "Yes, My Lady, I have."
"Then perhaps you remember the passage in which he said 'War is fought by human beings'?"
He gazed at her for another long moment, his eyes almost as opaque as they'd been the day she discovered he was her new flag captain, and then he nodded a second time.
"Yes, My Lady, I do," he said in a rather different tone.
"Well, it's time to find out if he's still right, Captain. As soon as Commander Sewell has that course for you, get us moving along it."

At this point both sides had analyzed the situation and come to the same conclusions: if Honor's force fought Theisman's force, then both would be battered but the Haven side would likely win. The difference was that Honor was prepared to die to give her side a chance to win, while Theisman was not prepared to die if his side had a chance to lose. Better to live to fight another day.

I never tried to insinuate that chess is the same as war, or that there aren't serious differences. My only point is Every war or battle is a chess match, and all generals play chess. I saw no need to comment on George Elliot's passage. There are differences between games and the real thing, of course. Chess pieces do not have minds of their own. However, the player pulling the strings DOES have a mind of his own, and a distinct personality - therefore, how one uses each piece from player to player is as different as night and day. Personalities, are programmed into electronic chess games.

Chess is NOT a good approximation of military moves. It is A DARN GOOD imitation of.

The chapter you quoted of Honor against Theisman happens quite a bit on the chess board, when an opponent brings his Queen in direct opposition to yours. What kind of player is he, are you? Will you simply exchange Queens, the most powerful pieces on the board? Or will one of you reject the offer, because the game is played by human beings.

Grant and Lee might've been able to solve "Who's the sharpest stylus in the box" over a friendly game of chess.

There are many vehicles used to teach strategy and tactics. Chess is an age-old vehicle that has withstood the test of time.

BTW, in 3D chess, it doesn't matter very much that you can see your opponent's every move. However, knowing your opponent may help. Chess also teaches you to study your opponent. "Know your enemy."

A couple other pointed chess tactics found in the series . . .

- En passant = Firing energy weapons when passing an opponent.

- Sacrificial moves. Honor always sacrificed as few men as she could, but sacrifice she did. The MA's "personality" rewrote the book on sacrifices.

cthia wrote:I never tried to insinuate that chess is the same as war, or that there aren't serious differences. My only point is every war or battle is a chess match and that all generals play chess. I saw no need to comment on George Elliot's passage. There are differences between games and the real thing, of course. Chess pieces do not have minds of their own. However, the player pulling the strings DOES have a mind of his own, and a distinct personality - therefore, how one uses each piece from player to player is as different as night and day. Personalities, are programmed into electronic chess games.

You seem to be arguing against yourself in these two sentences:

1) "I never tried to insinuate that chess is the same as war, or that there aren't serious differences."

2) "My only point is every war or battle is a chess match and that all generals play chess."

We have no statistics on how many generals play chess versus poker or any other game, so lets dispense with that part of your second statement. Certainly it is hard to square the first statement with this earlier quote:

If you don't see every battle as a chess match, you've already lost against this opponent.

The only mention you make of the question of resources is this:

Chess is designed to be a game that determine the strengths of a superior intellect. Not the strengths of a bigger economy, bigger naval budget, bigger production lines., etc.

Which can be taken to agree with your agreement that there are "serious differences" between chess and war. So we do not know what you really think.

Is it there are "serious differences" between chess and war?
Or else
Is it "every war or battle is a chess match"?

The point that you are missing, and it has always been one of your most glaring shortcomings, is the recognition of what chess actually teaches.

Chess teaches one to apply what one has learned, to life. Concepts are what is important.

My father's rendition is . . .

"Always think outside the box, where life is." And, "Life is in the conception."

Or the age old version "Don't miss the forest for the trees."

If you are too hard-wired with tunnel vision, you miss the forest for the trees.