That's why you're talking past each other, he's not playing your game.
It's Not Canon!
- Thread starter robject
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That's why you're talking past each other, he's not playing your game.
True.
TTA was written for CT, before the M-drive nerfing in later versions.
I've got a scenario I'll run eventually that involves matching velocity with an unidentified object in deep space that's inbound to a world at 0.3c (vector-matching takes 1.5 weeks at 2G). I'll have to waive the nerf to make it possible.
Not only does the PC's ship have to get up to 0.3c, so did the object...
Straybow
SOC-14 1K
I wrote six paragraphs on penetrating defensive detection: speed, size of the projectile, problem of detection coverage. Did you read them?Again, irrelevant without CONTEXT. Plenty slow for interdiction. Which is what I said it was for. Reread what I posted. Since ANY spaceship entering or maneuvering ANYWHERE in a system will be spotted by the local star faring military at the speed of LIGHT, anyone trying to accelerate a rock will be noticed, tracked and countered LONG before anything gets near a planet. If even nominal preparations have been done.
Do you understand what I have laid out? Do you have a scenario envisioned that actually counters what I wrote? Just saying it is "fast" without anything else is not really a reply nor a retort.
Of course, your handwavium detection system is flawless. I'm unconvinced such can exist in Travelleresque technology.
What I didn't cover is likelihood of detection. You haven't convinced me that instant and automatic detection at AU or multiple AU range is all that likely. Sure, a standard ship running in the open will be picked up within minutes of crossing the threshold of detectability. A small craft, fitted for stealthy operation, on a vector well away from the normal traffic, and possibly much farther out than normal traffic? Not automatic.
I agree, if the ship were trying to penetrate all the way to the main world it would be picked up in time to intercept. I showed that a 1 ton rock, less than a meter across, would have ~250 MT impact potential. I don't see detection being automatic, not at a range in time to intercept. It would only take 27 seconds to cross cislunar space, for example, so detection at that range would be insufficient.
If the attacker feels detection is likely, the rock could be prepared with stealth coatings to mitigate that. Such a small rock may in fact be entirely artificial, made of materials beneficial to stealth.
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Proneutron
SOC-13
That is why I wrote it in this thread for him to read.
Proneutron
SOC-13
Yes, and none work against what I wrote unless the defenders are low tech or the defenders decide to not defend. You cannot avoid detection at all. If you take a Jr. High physical science class it will cover why you will be detected at multiple AU range. Or, go here for a distillation: http://www.projectrho.com/public_ht...mbat_Sensors--There_Ain't_No_Stealth_In_Space
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Straybow
SOC-14 1K
"If the spacecraft are torchships, their thrust power is several terawatts. This means the exhaust is so intense that it could be detected from Alpha Centauri. By a passive sensor."
I would agree, except M Drive is not rocketry. The fuel is insufficient by at least two orders of magnitude. Only grav tech fits. The whole Atomic Rocket site is based on thermal rocketry and thermal imaging, and transit times of months or years at a few km/s. Not like Traveller at all.
"A long-range missile pod, launched from a merchant ship on perfectly legitimate business weeks or months previously, or from a mass driver at some obscure base, can stage a surprise attack with a significantly lower chance of early detection, and no worries about the crew’s survival."
I should think a cold, dark rock less than a meter across, at 15000 km/s, would be exceedingly tricky to pick up. A launch or boat, running cold at that speed, minimal power to slowly vector off the launch trajectory, also fairly tricky to pick up.
The greatest technological unobtainium in Traveller, after jump drive and reactionless grav drive, is how a starship handles the heat of a fusion reator in the GW range. Ships shed this heat harmlessly, somehow, even allowing downports with people in shirtsleeves walking around the ships.
Sure, normal starships wouldn't have special anti-radar coatings and anti-thermal systems, but expensive stealth ships would probably be possible. Perhaps LH2 could be pumped through cover plates mounted off the hull before going into the power plant. That particular idea would make atmospheric operations difficult, but can't be the only idea.
mike wightman
SOC-14 10K
The m-drive may be pure gravitic handwavium but that still doesn't explain where the waste heat from a gigawatt to terawatt fusion reactor goes - which would be very detectable. The only way this makes any sense to me - and your observation concerning downports - is for there to be a heat sink based on magic gravitic technology.
But I have the horrible feeling that the laws of thermodynamics would have to be broken by a gravitic heat sink.
But I have the horrible feeling that the laws of thermodynamics would have to be broken by a gravitic heat sink.
Proneutron
SOC-13
Quite correct. Fusion PP equipped spaceships glow like a spotlight against the cold background of space. Equipment you could purchase in the year 2,000 A.D. (TL 7) at a Walmart could be used to detect them at LEAST as far as the asteroid belt. At TL 9+? Easily all the way past the orbit of Pluto. Gravity drives aren't going to alter that. There is no such animal as a gravity heat sink. If you alter thermodynamics that much then your power plant doesn't function and you have no energy to push a rock up to fractional c speed.
Straybow
SOC-14 1K
Everything breaks the laws of physics. Since when do we let that stop us? :coffeesip:
Well, I have my ideas on that. Adiabatic cooling in a gravity gradient. Normal gravity doesn't have a steep enough gradient outside your friendly neighborhood neutron star or black hole. Exhaust gasses could be expanded in a sharp gravity field, perhaps combined with a gas turbine to increase it's thermal efficiency.
David Weber's Honorverse uses "gravity bands" for both shields and propulsion. I would make it only work over short distances between emitters, so it can't be used as an external defense shield. It would be really useful for internal security. At full strength even light would be deflected to such degree that only a diffuse glow shows the general light level on the other side of the field. As reactor shielding it would be effective against fast neutrons and contain plasma without conducting heat away.
A lower level field can be used to expand and cool a plasma or gas, also accelerating it without a physical nozzle. It doesn't allow large mass flow, but it can be used with reactor exhaust which is typically in the grams per second range.
Plasma is cooled by drawing off energy with magnetic manipulation of the reactor stream, by passing exhaust through MHD and inverse cyclotron, and maybe tricks we haven't thought of yet. At each stage some of that energy can be pushed from thermal to kinetic with a gravity gradient nozzle. When the plasma cools enough to be considered a partially ionized gas it can be further cooled and accelerated prior to each stage of a triple expansion turbine.
Finally, the creation of a jump field converts thermal energy into "dimensional energy" (we don't even have a name for it since we don't have gravity/dimensional tech). The final exhaust stream is used as a thermal source for an expanding jump field that is given just enough energy to draw off heat, which is converted into gravitational waves (or gravitons, whichever theory you like IYTU). Gravity waves / gravitons can have huge energy levels without being inconveniently deadly, like those pesky gammas and x-rays.
This does mean that a ship would have a very detectable gravity signature, but directional detection would be lousy. One would know that a ship was over there (maybe in a solid octant) and maybe within an order of magnitude distant (1-ish, 10-ish, 100-ish AU).
mike wightman
SOC-14 10K
I am stealing this...
apart from the jump drive component.
Spaceships such as SDBs and monitors need to dump a lot of heat too
It may explain the high power plant fuel requirement, most of it is dumped as supercoolant over the four weeks.
apart from the jump drive component.
Spaceships such as SDBs and monitors need to dump a lot of heat too
It may explain the high power plant fuel requirement, most of it is dumped as supercoolant over the four weeks.
Proneutron
SOC-13
Right, which shows up as a HUGE heat plume around the ship as you fly around space.
No worries.
Diffuse it, and use the hot blob as camouflage to futz enemy targeting sensors.
Result: vessel is easy to detect, but really hard to pinpoint.
Condottiere
SOC-14 5K
If the Dean Drive is kinetic, and you can change heat into kinetic, possible through expansion of materials or excited electrons, you have two birds with one stone.
Proneutron
SOC-13
Nope, thermodynamics doesn't allow you to get rid of heat that way. Entropy is higher. Better to use water as a coolant; better heat carrier and is not insidious like hydrogen.
Straybow
SOC-14 1K
Help yourself. I searched any way to dispose entropic heat, and I figure capturing into extradimensional space fits with hypothetical jump space. It can't make it disappear entirely, though. Too easy. Thus, transforming it into gravity waves / gravitons.
I didn't want simple grav tech to be a catch-all. I'd already decided that the collapsing jump bubble would release grav whatevers. My scheme is a bit more complex than this description, tying it all together. I tried to read up on superstring and related thinking to understand why 11 dimensions. Second year calculus doesn't cut it... so I made up my own handwavium theory.
Probably downright laughable to physicists.
mike wightman
SOC-14 10K
Not laughable.
But...
[rant mode]
gravity isn't a field, or a force or a well, but gravity waves are real. If general relativity is going to be contradicted it is going to take one heck of a theory that can actually be experimentally verified.
Despite decades of work on string theory, superstring theory, membrane shenanigans and extra dimensions - sometimes ten sometimes eleven - many physicists and mathematicians are starting to suggest the heretical view that string theory et al is a dead end and that the dogmatic adherence to it is simply a waste of resources, time and brainpower.
In a similar vein the view is being expressed that gravitons and quantum gravity will likewise draw a blank.
We know that general relativity works, we know quantum theory works - indeed quantum field theory is often touted as the most accurate theory ever - shame about the vacuum catastrophe showing there is a flaw somewhere. It could be that the two can never be unified in a GUT.
We know black holes exist, we know general relativity describes them to a point, but that quantum mechanics can not describe gravity at the quantum scale of things - physicists have been suggesting that it is quantum mechanics that will 'win' but the real answer is probably that they are irreconcilable and that a much cleverer theory will be required - new physics.
The universe makes black holes - our maths and physics breaks down when trying to describe them, therefore our maths and physics is wrong and needs fixing, not the universe.
There are other examples - I already mentioned the vacuum catastrophe - then there is dark matter, dark energy and other holy cows that are great hypotheses but have absolutely no experimental evidence to back them up. I cry a little when eminent scientists claim they must exist - that's what they said about phlogiston and the ether.
Time will tell, but dogmatic adherence to unproven hypotheses is probably not the answer.
New physics is needed, and this could open up new possibilities - just look at how antimatter was discovered and how we have used it since...
We need something beyond quantum field theory and general relativity - but whatever it is has to be able to produce the same observational and experimental results as GR and QFT[/rant mode]
But...
[rant mode]
gravity isn't a field, or a force or a well, but gravity waves are real. If general relativity is going to be contradicted it is going to take one heck of a theory that can actually be experimentally verified.
Despite decades of work on string theory, superstring theory, membrane shenanigans and extra dimensions - sometimes ten sometimes eleven - many physicists and mathematicians are starting to suggest the heretical view that string theory et al is a dead end and that the dogmatic adherence to it is simply a waste of resources, time and brainpower.
In a similar vein the view is being expressed that gravitons and quantum gravity will likewise draw a blank.
We know that general relativity works, we know quantum theory works - indeed quantum field theory is often touted as the most accurate theory ever - shame about the vacuum catastrophe showing there is a flaw somewhere. It could be that the two can never be unified in a GUT.
We know black holes exist, we know general relativity describes them to a point, but that quantum mechanics can not describe gravity at the quantum scale of things - physicists have been suggesting that it is quantum mechanics that will 'win' but the real answer is probably that they are irreconcilable and that a much cleverer theory will be required - new physics.
The universe makes black holes - our maths and physics breaks down when trying to describe them, therefore our maths and physics is wrong and needs fixing, not the universe.
There are other examples - I already mentioned the vacuum catastrophe - then there is dark matter, dark energy and other holy cows that are great hypotheses but have absolutely no experimental evidence to back them up. I cry a little when eminent scientists claim they must exist - that's what they said about phlogiston and the ether.
Time will tell, but dogmatic adherence to unproven hypotheses is probably not the answer.
New physics is needed, and this could open up new possibilities - just look at how antimatter was discovered and how we have used it since...
We need something beyond quantum field theory and general relativity - but whatever it is has to be able to produce the same observational and experimental results as GR and QFT[/rant mode]
Proneutron
SOC-13
"Scientists" are too quick to call theory and then hold it dear. String theory cannot really be thoroughly tested as written. Mathematical tests/proofs cannot be substituted for a physical theory. Less rigid "belief" in untested ideas is called for. BTW, curved space is what well call a gravity "well".
And you cannot convert energy from high to lower state of entropy. Thus, heat cannot be rid of in that manner. Otherwise the entire universe winds UP instead of down.
Condottiere
SOC-14 5K
It's magnetism.
Whether electro or animal.
The Law of Attraction.
Whether electro or animal.
The Law of Attraction.
mike wightman
SOC-14 10K
I agree.
By the way it really isn't.
Curved spacetime is a thing, but the way people use the term gravity well is usually erroneous.
You can not convert energy to entropy at all, they are completely different parameters.
You can use energy transfer to reduce the entropy of a system, but you pay for it by raising the entropy of the rest of the universe - go look at your refrigerator or freezer for examples of machines that reduce entropy inside but raise entropy outside by the transfer of energy.
Proneutron
SOC-13
How so? It's pretty simple example that works well enough (no pun intended) to describe the observed result in 2 dimensions.
You can use energy transfer to reduce the entropy of a system, but you pay for it by raising the entropy of the rest of the universe <snip> [/QUOTE]
In short, we cannot take waste heat from a PP and convert it to anything to disguise or hide the heat. That is the OPPOSITE of how the universe works. Whatever semantics we use to describe it.
