16 May 2013

FWS Topics: Science Fiction Space Travel Myths

Sometimes, the realities of science and physics make life difficult for a sci-fi writers and/or creator. It doesn't help us that the vast majority of science fiction is soft-serve that telling massive fictional space traveling myths. Another title for this blogpost should be: 'how sci-fi lied to us about space travel!' Once again, here is an improved FWS blogpost taken from an original io9.com article about the top ten space travel myths that populate science fiction like the common cold or an STD at a college dorm. FWS reworked the original post, adding new pictures, and original FWS patented research and text. There was some sci-fi space travel myths that I omitted from the original io9.com list, and added a few of mine own. Here is the original io9.com post:
http://io9.com/5936924/10-myths-about-space-travel-that-make-science-fiction-better

1. Faster-Than-Light Space Travel
There is no greater lie in the realm of science fiction space travel than faster-than-light propulsion devices. FTL 'warp drives' are like sci-fi peer pressure, we all do it, and we expect others to do it, too. Mainly, FTL travel has to exist for most sci-fi tales to work according to the author's vision of visiting strangle new world and seeking out green-skinned slave women.Of course, propelling a starship faster than 186,000 miles-per-second is considered unrealistic in physics due to an infinite amount of energy needed to accelerated an particle with rest mass. Even more impossible is faster-than-light space battles where torpedoes and phaser beams bounce between the warships...does this mean that phasers operate above the speed of light, and that torpedoes have micro-warp drives? There could the possible of some particle that do move at FTL speeds, tachyons, or there could be something like B5 hyperspace dimension that allows for FTL travel or even once a civilization creates FTL starships, an alternate reality is forged where everyone is the same, save for the goatees. This has been hammered away by this blog and another sites...so, we don't need to bet a dead horse. There are few science fiction works that feature the complications of space travel without FTL, Firefly being the most popular. But for the most part, science fiction fucking loves FTL travel, and it is hard not too.

2. Magical Artificial Gravity Generator 

Gravity. It allows plastic surgeon to make their Porsche payments, apples to fall, and drinking glasses to smash, and it is one of the greatest roadblocks to deep space travel to the stars. Our bodies were developed for operation on this planet that has gravity, and the effect of years without gravity could cause massive medical issues for our space trekkers. It the world of sci-fi, nearly every starship has some sort of soft-serve magical artificial gravity generator that works even when main power is knocked. Artificial gravity could be created using rotating sections, creating centrifugal generated 'gravity', and these ships would have be designed around this concept...just look at the USS Discovery's habitation decks from 2001: Space Odyssey. Even with rotating sections, only portions of the ship would have a gravity environment, and it would not be the same has back on terra firma.
The ABC show Defying Gravity used magnetic particles in the blood, hair, on the bottom of their shoes coupled with rotating sections to mimic Terran conditions. You could achieve artificial gravity via linear acceleration that created gee-force. The issue is that fuel would be expelled during this process, and could not be kept up for long-term space missions. Low-gravity environments have been proposed for a trip to Mars via low-impulse acceleration...it wouldn't be Terran-normal, but it would be something. Or, lastly, build a 1300 billion ton starship (!), to create natural gravity. It would be easier to strap rockets to the Earth!  

3. No Inertia in Space Travel 
Inertia is the resistance of an object to change its state of motion...or objects keeping doing what they're doing until they are forced to change...also called marriage. I used to love, when I had my manual transmission Honda Civic, to roll down this steep hill near TCU without any gas, and this is one of the great saving graces of real-world space travel...inertia. Inertia would allow our starships to accelerate to a certain velocity, then cut the propellant, and ride the inertia nearly all the way to the objective. However, this does not exist in a great deal of space-based sci-fi stories, especially sci-fi TV shows. Often when the ship runs out of gas, they stop, or if the captain orders 'all-stop' the massive starship nearly instantly stops without a massive de-acceleration method. Any real-world space mission would have have phases of acceleration, cruising, then de-acceleration. If you are accelerating  for an year, then you are de-accelerating for year...as Bender said: "the laws of science be a harsh mistress." Science fiction also likes to dismiss the 'for every action, there is an equal reaction' law with massive accelerations and de-accelerations with the aid of handwavium inertial damping devices that prevent the crew from being turned into chunky salsa.

4. Superluminal Interstellar Communications
How could there be an Terran Empire, or Federation without the possibility of interstellar real-time communications? Well, according to Einstein, interstellar faster-than-light phone calls would be on the same level as time travel. What does this mean of the off-world colonies? They are on their own. Even now, Voyager 1 space probe's radio signals take 16 hours to reach Terra, and the probe is in our solar system...can you imagine being separated by light-years? One way that science had suggested for interstellar communication is sending the signals or dronesl through a wormhole...if they work like an galactic subway. Now, things get even more complex and beyond my limited science education when we take into account FTL communications between two starships moving at near lightspeed! The possibility of interstellar real-time communications could make for an interesting spacefaring future...

5. Crowned Space
Everyone always says how big space is, but somehow, that is never communicated effectively when it comes to massive space fleets. Nearly every space fleet seems to pack themselves in a nicely cropped shot, presenting a nice juicy target for incoming Cylons...but why? There doesn't seem to be any logical reason, save for media presentation of the classic space fleet that is based on seagoing navies. Not only does this apply to space fleets, but to asteroid belts, planets in a star system, and moons relative to their parent planet.

6. Instant (just add water!) Communication with Alien Species
Every week on Star Trek or Stargate, our intrepid heroes teleport off to new worlds that look like back-lot or Canada and met bumpy fore-headed aliens that speak prefect English, or our heroes iphone universal translator app works perfectly. The sad truth is that communication with an intelligent alien species that evolved on a completely different world than us would be a long, painfully process, requiring experts in the field of linguistics to live with these aliens. After all, when we sent probes out into deep space, those golden discs used symbols, math, and sounds to communicate. I realize that sci-fi stories have to use the equivalent of the microwave dinner to accelerate the plot and make for the vision of populated galactic community, but sometimes it takes away from the 'alieness' of the creatures, because we can talk to them instantly. One of the my favorite sci-fi books about this subject is Mary Doria Russell's the Sparrow.

7. Rise the Shields!
Anyone that watches enough Trek knows that once the shit hits the fan, the shields go up, and if these shields collapse during space engagements, the good ship Enterprise is fucked (cough* Generations* cough). Traveling through space at a great rate of speed and engaging in space pew-pew laser battles would be much easier with force shields, and not the massive whipple shields of hard science. In reality, warships would use defensive automated laser emitters and kinetic interceptors to prevent incoming hostile fire, like current naval warships. The stable electromagnetic barrier that are used in Star Trek could be used on a small scale to possibly replace iron bars on prison cells. A wall of electrons, synced up with the same quantum state has our own body's electrons, that using the Pauli Exclusion Principle to prevent that body from passing through this wall of electrons.

8. Starship Appearance
One of the greatest sins committed by science fiction is the appearance of the starship in science fiction. For much of the early years of science fiction, especially during the Space Race, atomic rocketships dominated the space lanes. That was until about mid-1960's, when spaceborne ships like the Enterprise showed us all there was other schools of starship design, but still unrealistic. It was assumed by some that space is like the ocean, and spaceship design should follow, much like the Galactica and the Yamato. What become a rarity in science fiction was the hard-science deep space vehicle, like the Antares, the Phaeton, and the ISV Venture Star. These are brittle-appearing long ship with drive sections far away from the habitual sections, spinning artificial gravity arms, glowing heat radiators and massive protective whipple shields. These are beautiful in their own ways, but are unpopular with sci-fi fans that grew up with visions of Star Destroyers and Birds of Prey dancing in their heads.

9. No Time Dilation

Time dilation is one of those an inconvenient truths of physics that could make traveling to distance stars incredibly difficult for future generations. To deal with this problem, the vast majority of science fiction pretends it doesn't exist or that there is an magical hyperspace corridor that cancels out the effects of time dilation. For an author/creator to include time dilation means that critical points of the plot will focus on this factor, instead of zipping from star-to-star while getting synthohol at Ten-Forward. Because of the indoctrination that soft-serve sci-fi has programmed into the collective consciousnesses, it is very difficult to reconcile worlds like Trek and Wars with the time dilation in the real-world. Ugh. FWS has discussed this space phenomenon to death on many blogposts and will continue to discuss it...sorry in advance for that.



10. Sheath In Space
For years, science fiction has pumped visions of submarine warfare in the soundless dark void beyond Terra, invisible green alien warships waiting to destroy our science ships, and sneaking into enemy territory on a covert commando mission. It makes sense on one level of thought, especially to those of us indoctrination with a lifetime of soft-serve sci-fi...but not when closely examined under the hard science killjoy lens. Space is dark and vast, but the waste-heat from our starships would blaze like a bonfire in the dark realm, coupled with the realities of space-based propulsion blazing its own "we're here" billboard. Sci-fi has developed all manner of inventive handwavium sheath shields, and material that absorb detection waves and beam and that's fine if your sci-fi universe is well composed and interesting.

15 comments:

  1. As usual great article that pinpoints hard-science impossibilities in most of sci-fi. Keep those kind of articles coming as they're always very well written and informative.

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  2. Thanks! Sometimes I think I beat some of the hard-science point to death. But, io9.com did a terrible job with the original article. Thanks for reading and commenting!

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  3. Christopher PhoenixMay 18, 2013 at 6:41 PM

    Interesting post, William- reconciling the physics of real space travel with the SFX versions we've all been indoctrinated by in TV shows can be difficult. :D You put together a pretty good list, although I would add the radiation health hazard of deep space travel (one of the BIG obstacles).

    In general, the mechanics of space travel is ignored by most SF shows and books- especially since classical physics, orbital mechanics, and relativity are all considered complex, math heavy subjects!! But if you are really interested in spaceships you should learn something about them- at least you can then understand why the spaceship must fire its engines pointing the wrong way to rendezvous with its destination, and why FTL travel is considered impossible (at least without discovering some unlikely physics loophole, which most physicists aren't holding their breath for).

    SF movies love showing closely packed together space fleets- which isn't strictly wrong since you could fly spaceships in such a formation. But, I am more annoyed by the fact that opposing spaceships often approach each other at very low encounter speeds at point blank range- if you fly at dozens of km/sec to reach the outer planets (let alone warp speed), why are you always wallowing around at Trafalgar range? It seems unlikely you could close to a few hundred meters with an actively maneuvering, shooting enemy!

    I suppose visible laser beams in vacuum would be another error commonly practiced for sheer SFX on-screen glamour.

    As for shields- magical bubble barriers that absorb laser fire and deflect material objects have been a common SF invention sense EE. "Doc" Smith's early stories, but there doesn't seem to be much chance of replicating these functions easily. Uncharged objects cannot be easily manipulated by electromagnetic fields, gravity is too weak, and the nuclear forces remained locked up in the cores of atoms. Nor can these forces being shaped into a thin bubble or flat wall- in most cases, the force grows greater the closer you approach the source.

    Where did you hear about stable electromagnetic barriers replacing bars in prison cells, William? The only sort of stable barrier of electrons capable of excluding humans by the Pauli Exclusion Principle I know of is- an ordinary wall. XD .

    A few hypothetical devices do resemble the deflectors of Star Trek, like ionizing interstellar hydrogen with a laser and deflecting it with an electromagnetic field to avoid being roasted at high relativistic speeds. But for the most part you will be stuck with armoring your spaceship's hull, dodging debris, or destroying it with high energy lasers before it hits your ship.

    I think there is a lot more leeway on how you want to make your starship look than just a long spine with heat radiators, just look at the number of shapes seen in NASA designs!! Most of them won't look anything like boats, however. Solar sails do have rigging, at least.

    I found it funny the Io9 article mentioned ray-guns vaporizing people- I guess the trusty blaster IS a necessary piece of equipment for the enterprising cosmic traveller, so perhaps it is appropriate. XD I don't agree that it is impossible to vaporize someone. Any proper disintegrator will have to apply a great amount of energy (hundreds of megajoules, if basic calculations are correct) to the hapless humanoid target quickly enough that the target can't radiate it away before it is super-heated and vaporized. But, if it were true that pumping energy into a target is like trying to fill a bathtub with a very large drain, military lasers wouldn't be able to melt metal before that metal radiated the energy away. This is a pretty well understood factor, and if you could scale up that laser enough- I see no reason someone couldn't be "melted" by a laser. It just isn't practical- yet.

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    1. What about using "quantum energy? Using tiny black holes that open and collapse you could use it to create a burst of energy. This could then fold space time, minimizing the fuel required. I remember in the show Cosmos they said you would need the combined power of a few million h-bombs. I learned about this theoretical form of power from Guinness world records. It said that one cubic centimeter of all of these microscopic black holes(their so small that they can't consume any matter) the energy in one massive burst could boil the worlds oceans. Create a device that can harness this and then release this energy in one massive burst and boom- you could have a jump drive. However we don't understand black holes, don't know how to harness it and don't know how to make it safe and accurate(no way to "jump" to a specific place).
      Another idea is exploiting an interesting idea: If I'm not moving, but instead, I'm contracting space spacetime time behind me and and opening in front of me , it might be possible to go the speed of light.

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  4. When I saw the ray-gun vaporizing setting, I thought of our discussing, and I will be adding that sci-fi idea on the LASERS post...which is being worked on...I just got the photo collection done for it.
    I almost added space radiation because the io9.com article mentioned it, but I felt that energy shielding was a better fit.
    The long spine with heat radiators spaceship is one of those designs like the whole space boat idea that is also becoming too common.
    I read the idea of using EM fields for prison cells of a sort on a physics website, and it was buried deep in the article and forum...took me hours to read all of it.
    I can still remember watching some of the big fleet battles in DS9, and thinking that somehow this didn't make much sense, especially like you said about slow speed...know I know why. Even the Trek starship combat simulator games cause you engage hostile warships are very close ranges...even when compared to blue-water naval engagements.
    My favorite recent error with sci-fi space travel is watching the NewTrek Enterprise fall out of orbit and crash towards Earth. If the M/AM containment was damaged than Earth would be Fucked...of course, Terran standard gravity would crush the Enterprise...that design is completely space-only rated. Silly J.J. Abrams...gods, I hate NewTrek!

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  5. I don't think you're strictly correct about stealth in space; it *could* work if the system is a method of dumping waste heat in a way that your opponent's sensors aren't designed to detect. Remember it's not about being invisible, it's about appearing to be so small that your opponent's targeting systems discard you as clutter because if they didn't they'd be shooting at every tiny bit of debris that passes their way. That would mean that cloaking device design was a perpetual arms race between finding exotic ways of disposing of waste heat and sensor designers figuring out what the enemy ship is doing and how to spot it.

    Also vapourising a human is ridiculous because turning someone's entire body into gas in a split second would be causing them to *explode*, and generally causing gigantic pressure waves is not a desirable trait in smallarms. Let alone cooking everything in the room with you with scattered heat from your absurdogun.

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  6. Also EM fields for prison bars is a great idea until you realise the benefit of steel bars is they don't vanish when the power goes out.

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  7. Absurdo-Gun! Love it! May make a blogpost with that title!
    The stealth in space topic is not one I claim much knowledge on yet...Atomic Rocket and the Rocketpunk blog both devoted articles on way stealth cannot work in space...I think there could be a way to hid some types of ships.
    Stealth technology is designed not to make the fighter or bomber invisible, just to be the size of a sparrow...
    If you wanted to explode someone, high-powered microwaves or even a plasma steam could flash-boil someone's body...pink mist, baby!

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  8. Christopher PhoenixMay 22, 2013 at 4:07 PM

    The classic problem with stealth in space is that waste heat from power plants, life support, etc. must be radiated away so that the ship does not cook- but this infrared signature will reveal the ship to enemy infrared sensors. The idea of trying to refrigerate the side that faces the enemy, i.e. having a cold and hot side, might work- similar technology has been used on the Spitzer infrared telescope to keep the scope from blinding itself- but will require complex equipment, evolve still more waste heat, and can be defeated by the simple expedient of placing sensor platforms all through the solar system so that the hot side of the ship always faces a "sky spy". Not to mention that the flare of propulsion rockets will give your "stealth" ship away the moment it tries to maneuver.

    A possibly more fruitful endeavor would be trying to conceal spaceships by making them look like natural asteroids or comets. This might be done by surrounding a spaceship in a kind of "mask" made to resemble a cratered a pitted surface, and perhaps modifying the exhaust trail to resemble a comets tail- as is done in Stanislaw Lem's novel "Fiasco".

    Anonymous is, however, wrong that boiling someone away necessarily creates a huge TNT-like explosion- a big cloud of scorching vapor, yes. But simulating a high explosive requires that the decomposition occur faster than the speed of sound in the material so that it is "shocked", i.e. a wave of compression travels faster than sound through the target. This requires dumping that energy in very rapidly. Vaporizing someone through intense heat will definitely create a cloud of expanding, scorching vapor and likely ignite or melt nearby objects. And, it doesn't have to be a "split second"- some ray-guns take quite a few seconds to finish the job. On a side note, the sidearms in Men in Black do indeed make aliens explode. :-)

    I have heard that a radiant flux over 400 J per square centimeter applied in a pulse of a few seconds or less is sufficient to cause a victim's flesh to flash into steam and flay exposed areas to the bone, which is probably close enough to a "skeleton beam" for most alien's purposes. Such gruesome effects were investigated during the Cold War as part of research into the effects of nuclear weapons, which primarily kill via radiant energy emitted by the fireball.

    If you've noticed, though, some "disintegrators" in SF seem to work via primarily thermal effects (burning a target to ashes) while others, like the MiB blasters, seem to explode people by flash-boiling their insides. And others, like the Skeleton Beam from the original War of the Worlds, claim to use such fanciful effects as "neutralizing mesons" to cause matter to "cease to exist!!" while others claim to disrupt the electromagnetic bonds between molecules to cause matter to fall apart into dust- SF writers have imagined all manner of disintegrator, really.

    On the reality side of things, a laser weapon can work off of primarily thermal effects (raising a targets temperature high enough to melt or vaporize it) or by mechanical means- such as emitting short pulses that create pinpoint plasma explosions to deform and tear the material instead of vaporizing all of it, which usually requires less energy but is not quite as sure a means of destruction.

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  9. Well, I was talking more in terms of less-hard scifi; for example, in Star Trek they have so many exotic particles, radiation forms and divisions of space that there's a lot of scope for getting rid of waste heat by turning it into something your enemy isn't looking for. Slightly less applicable on the hard side of things, but there's still some wanky exotic states that you could put it into that would be harder to find than just venting it out the back.

    Re: gunsplosions, it's kind of hair-splitting; the point is turning the entire target to boiling vapour isn't often going to be a desirable effect in a smallarm. For example, you won't be able to deal with a hostage situation without killing the hostage.

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  10. Christopher PhoenixMay 23, 2013 at 4:01 PM

    Well, I have studied some thermodynamics in science courses and the general impression I got was that waste heat is waste heat, and there isn't much you can do to get rid of it except to radiate it away or store it in a heat sink (as was done in the Eagle lunar lander to keep the battery cool).

    Ironically, in ST the dastardly cloaked Romulans and Klingons are more often than not revealed by electromagnetic emissions from within the cloaking field, and in one case by the plasma trail created by the impulse drive. If someone can kill your "cloaked" ship by making a few modifications to a standard torpedo, one wonders what use the cloak really is...

    I was thinking along the lines of the "vaporization" being more of a deflagration (somewhere between "burns quietly" and "explodes") -but I certainly wouldn't want to be standing right next to the victim when this much energy is being dumped into it. Excess energy spilling over from the beam and the effects of a cloud of hot vapor would not be pleasant standing right next to the target. Many ray-guns in SF have multiple settings, so futuristic gun-handlers can select a lower power kill setting that leaves a body, or the ever-popular stun setting for such a situation.

    I doubt anyone carrying around a De-Atomizer capable of completely vaporizing a humanoid target if wants to minimize the damage, though. :-) Sometimes, as in Star Wars, such disintegrator weapons aren't even commonly used (except by criminals and the like) because they are impracticably powerful and considered barbaric. Except in such peaceful universes like Star Trek, lol.

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  11. Oh yeah, thermodynamics doesn't let you make a machine which produces *no* waste heat, and you're always going to be radiating something now matter what you do if you're generating power (otherwise your ship is constantly heating up). The goal for such a system would be shifting the majority of waste heat into some state / phase / dimension where it wasn't as easy to detect.

    Even the best stealth aircraft reflect *some* radar, but the idea is to reduce that to the extent that they don't look like what your enemy's radar system is looking for. Since if a SAM battery engages every single contact it'll be shooting down a *lot* of birds, you get by because it discards you as irrelevant.

    The same would apply here; you're trying to drop enough to look like you're not a valid contact, not emit nothing at all. Would probably work best if you were hiding near something emitting a lot of heat, and would be pretty situational all round.

    Though given how silly Star Trek chemistry can get (you can dig up alloy as ore, for example) you could probably just turn the heat into phlogiston and store it in a big tank somewhere.

    I think the issue with spilling would be that the resulting weapon would more closely resemble a flamethrower than a gun, and therefore be pretty limited in application; ok if you're some boarding team killing fangly alien monsters, I guess, but not much use in normal combat. And one good thing about, say, a carbine rifle is that you can mount a non-lethal underbarrel weapon (or an underbarrel space flamethrower with a replaceable capacitor / power cell assembly, if you prefer) rather than having to change out weapons completely at short notice.

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  12. Christopher PhoenixMay 25, 2013 at 6:46 AM

    Basically, thermodynamics simply tells us that all concentrated forms of energy eventually decays into "useless" waste heat that dissipates into the environment. All concentrated forms of energy spread out into less concentrated forms, and this process cannot be reversed. This sounds very basic, but the engineering applications of thermodynamics only barely hint at its implications. One way of stating the 2nd Law is to say that no engine can be 100% efficient at turning heat into work, but another equally valid way to think about it is to say that the disorder of a system always increases.

    Look around you, and you see the effects of the 2nd Law. Rooms get messy, and the only way to clean them is to expend effort cleaning it. People age and eventually die as errors and disorder in the machinery of their cells accumulate. Whole galaxies full of stars will eventually burn out and die, the dying echo of the energies they once unleashed dissipating as thermal radiation, and even the most powerful beings in the cosmos could not put them back together and reignite them. All the same energy is still THERE, just spread out into a form we cannot use.

    If you aren't the science-nerd type there is always the poetical form...

    "From too much love of living,
    from hope and fear set free,
    We thank with weak thanksgiving
    Whatever gods may be
    That no man lives forever;
    That dead men rise up never;
    That even the weariest river
    Winds somewhere safe to sea."
    -from "The Garden of Proserpine" , A.C. Swinburne 1866

    The image of the universe winding down like a clock is well represented by this poem, I think. Sorry, I always wax poetical if the 2nd Law of Thermodynamics comes up, and we were talking about hypothetical stealth for imaginary spaceships... XD

    But if we are talking in terms of the notoriously unrealistic Star Trek technobabble of states/phases/dimensions etc., what is the purpose of discussing hard SF thermodynamics? That series can't even keep track of the difference between joules and watts. As for dissipating energy as some "other form", how? We have heat. We can't turn into anything else because it already is dissipated into an unrecoverable form. There aren't any magical dimensions to dump this waste energy into. You can't reverse entropy to get rid of this heat. You can either radiate it into space or store it in a heat sink- which is strictly a limited-capacity device.

    But killing fangly alien monsters IS normal combat!!! XD Wait, did someone say phlogistion? http://www.youtube.com/watch?v=WBi1FYqaFus

    I find it funny you mention flamethrowers- melting enemy soldiers with intense lasers could be similar to using a long range radiant flamethrower, sans the burning fuel getting all over everything. Hmm, maybe more like a blowtorch. The analogy is apt if you simply focus a high-energy continuous wave laser on your enemies to burn and ignite their skin and clothing- vaporization is somewhat more extreme, however.

    It might be simpler simply to exhaust the waste products of modern chemical lasers in the general direction of the fangy alien monsters, though. XD

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  13. If you asked hard sci-fi enthusiasts back in the eighteenth-century about stealth in (then non-existent) aerial combat, you probably would have heard a resounding "no" from them as well (unless people were crazy enough to do it on cloudy days, of course). The Wright bothers thought their invention would make war impossible, since armies would find it impossible to move with anything resembling stealth - and that just shows how cautious we should be when theorizing about that subject. If you want war in space, you are going to need stealth - there's no way around it. So I forgive those who simply handwave it into existence so their spacewar doesn't merely turn into ritualized (and incredibly boring) slaughter. The reason we don't understand how stealth in space would work is because we simply don't have any practical understanding of warfare in that environment. But that's a far cry from simply stating it's impossible.

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  14. Yeah.
    Shields could be gravitational.

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