Here of late, Sam, I’ve thought that the best interstellar spaceship would be an asteroid that was hollowed out. If the exterior were several feet of rock, would it be able to survive a cloud of gravel?
BTW, everyone, Poul Anderson used the idea of a cloud of small objects being projected in a fleet’s path in a short story entitled “Cold Victory.” His fictional admiral used ball bearings rather than pea gravel. Same effect.
Again, the background temperature of space is in the range of 3 kelvin; that is three degrees above absolute zero. Even if you could create and insulate a cold temperature reservoir below this temperature, the maximum specific heat capacity of stable, solid state elements (lead or bismith) is only 122 to 127 J/(kg⋅K). One joule of energy is equal to 2.78×10[SUP]−7[/SUP] kW⋅h, which means that one kilogram of this theoretical cold temperature reservoir can absorb ~0.0001 kW⋅h for a temperature rise from 0 K to 3 K. It would literally require ten tons of mass to absorb 1 kW⋅h of waste heat over this temperature range.
There is a qualitative difference between declaring something “impossible” just because the power source or technical conveyance doesn’t yet exist, and something that violates the essential tenets of basic physics and fundamental materials science. The idea that perfectly adiabatic materials, the ability to somehow “move” heat around in a system (i.e. change the state properties) without doing work that contributes additional heat, or other ways of bootstrapping around the practical limitations of basic materials and the second law of thermodynamics “sounds like an engineering problem” belies a lack of understanding of the essential physical principles involved.
Stranger
Can a man shout in Carthage and be heard in Brittania?
You may prove that we can’t get around the practical limitations of vocal cords and the basic properties of air. I maintain that it’s an engineering problem.
You may “maintain” whatever pleases you, but the laws of thermodynamics are an absolute physical limitation that cannot be handwaved away by describing them as “an engineering problem”.
Stranger
I’m not sure you understand the analogy. They are an absolute physical limitation in precisely the same way they are when a person wants their shout to be heard hundreds of miles away.
The best scientists of the age believed that postoperative infection was a good thing, that blacks were inherently inferior to whites, that trains were dangerous because people’s bodies just couldn’t handle traveling that fast, that powered flight was impossible, and that the sound barrier was unbreakable.
We just can’t know what will be technologically possible centuries from now.
Sure you have repeated these things many times and I have responded to them.
No, I don’t mean those.
The essential part of a factoid is not that it’s false, it’s that it’s oft-repeated, unthinkingly.
The idea that hiding spaceships is impossible is something that comes up very frequently in discussion forums, blogs and vlogs, just google “stealth in space”.
In most cases, it’s enough to point out that the purported problems are just of a technological / engineering type. If the logic of “I can’t think of a practical way to do it, therefore it’s impossible” worked, then all of science fiction is impossible, by definition. To call something *impossible *we should need much more than just that.
To be clear though: if someone were to say “Stealth is space is much harder than implied in science fiction, and aliens, or humans in the future, may never even attempt it”, I would have no issue with that position. It’s just ruling it out as impossible which rings alarms for me.
(and adding “practically” or “virtually” in front of “impossible” doesn’t help in this context. We can say it looks very difficult to achieve, but we have no basis for implying it’s impossible or close to it)
Have you guys never heard of hyperspace? All ships that have cloaking devices naturally also have warp drives.
All that excess heat simply gets shunted off into hyperspace. Hyperspace is cold, man!
No more so than slaloming around seamounts along the mid-Atlantic ridge
Getting a little off topic, but I’m interested to hear from a submarine officer whether you thought Das Boot was realistic?
It certainly does capture something of the intensity, tedium, and slow pace of operations.
I served in an era of infinite power, free oxygen, and bottomless tanks of fresh water, so I can’t say authoritatively, but Das Boot seems to nail it.
Glen Cook had an interesting solution to the problem of energy and heat radiation in his book Passage at Arms. Basically, some specially built ships were able to “climb” out of both space-norm and hyperspace into a weird little space all their own, and their cross-section in space-norm and hyperspace was something referred to as a Hawking point. The Hawking point was so small as to be damned near undetectable unless the enemy was lucky or knew exactly where the ship had entered climb and had enough information about the commander, the ship’s capabilities, and its likely supplies, which information could then be used to calculate where the ship could be from where it had been and what was known of the ship.
The energy and heat from engines and the like? Climbers couldn’t radiate that at all while in Climb, so there was nothing to detect in space-norm or hyperspace. The downside, of course, is that it put real limits on how long a ship could stay in Climb.
And yeah, they actually had a rail gun along with torpedoes. The rail gun was new, and roundly cursed because it took away space that had been used for crew amenities. I forget what was lost for that trip, but they’d long since lost things such as lockers and showers.
So he got around a fundamental limit of physics by inventing new fake physics? What kind of solution is that?
Why was it called a ‘Hawking Point’? Did it have anything to do with Steven Hawking’s actual theories? Or was it just a way to use Hawking’s name to make it sound more scientific?
I have no problem with stories that violate fundamental physics. But they aren’t science fiction, they’re science fantasy or speculative fiction - as much as a world that has magic in it is fantasy. You can tell great stories in a magical universe, but they aren’t science fiction. Star Wars and Star Trek are both science fantasy.
As a reminder - since this thread is about futuristic infantry combat, you can’t have the discussion without referencing Starship Troopers by Robert Heinlein. The book, not the movie. The movie is dreck when it comes to actual combat. But the book is very meticulous in describing a future space-based infantry and what squad-level tactics might look like in the future. We’re talking about an infantry in powered armor dropping individually from orbit in ablative capsules. It’s fantastic. And yet I seem to be the only one who has mentioned the book.
I was about to suggest Iain M Banks. Apparently there are film/tv show in the works. Hopefully that part transfers to the screen intact (not very optimistic mind you)