Sleeper Ships

Sleeper Ships


This episode is brought to you by Squarespace
Sleep has been a necessity, a curse, and a great pleasure throughout human history. In the future, it might also be the key to
space exploration. Space exploration is a long, gradual process. Although even our earliest spaceships traveled
faster than any vehicle on Earth, the distances to our neighboring planets make the travel
time itself one of the hardest challenges to overcome. The distances to the nearest stars are so
immense that even light takes years if not decades to arrive. This is obviously a problem for traveling
to other star systems, at least if you want to get the original crew there. You can shorten the travel time by making
the ship faster, but fans of this channel know that physics puts an absolute limit to
maximum velocity for any given propulsion system. Science might extend the crew’s lifespan
enough to make interstellar journeys, however, there’s a question of how those years or
decades of boredom would affect them psychologically. So a more appealing option would be to just
hit the pause button on the crew’s lives. Today we’ll be looking at options for doing
that, suspended animation, cryogenics, and stasis. We’ll also examine how you might automate
the ship and the many challenges involved. On an interstellar voyage we’re not generally
concerned about the energy needed to support the crew. They have to stay warm and have lighting for
growing food, which requires a constant supply of energy, but would be peanuts compared to
the energy needed to speed up and slow down from interstellar velocities. This wouldn’t apply in every case though,
the energy necessary to maintain life support only drops to a trivial fraction of your budget
if you’re going over 1% of light speed. What’s more, you have to supply that energy
for the entirety of the journey from primarily internal systems, whereas your acceleration
energy to speed up and slow down can potentially come from outside the ship. You might be pushed up to speed by a laser
and we’ve discussed various way you might slow down without a conventional engine in
our episode Exodus Fleet. Such being the case, you might find it infeasible
to provide energy for life support the entirety of a journey, or may not want to allow supplies
and equipment to decay or wear down. We make a lot of assumptions about interstellar
colonization here, one of the big ones being that we have vastly superior automation that
would allow us to create and repair fairly sophisticated machinery while traveling. We obviously can’t do this now, and I don’t
take for granted that we will in the future. I do think it’s likely and I don’t think
you’d try a colonial venture to a distant star if you didn’t have that ability. But it may turn out that there’d be equipment
they couldn’t make en route or in situ just as we have plenty of things nowadays that
we can’t make or repair without access to a global industrial infrastructure. Such being the case, a ship might want to
minimize use of equipment and the associated risk of breakdown and decay by putting everything
on ice. Consider the freighter, a classic spaceship
traveling between two stars carrying perishable goods, they obviously want those arriving
intact. Folks often say that shipping material between
stars for trade is not realistic, that it would just be initial colony efforts, data
transfer, and maybe immigrants, but this is very debatable. A sufficiently developed system, such as a
Dyson Swarm under construction, could easily have a high, steady, and long-term demand
for raw materials. This sort of mass import of materials wouldn’t
necessarily break the bank either, at least in terms of fuel. So long as you travel slow enough, you could
ship things very inexpensively. You obviously still have to pay upkeep on
that space freighter, which would include salaries if it was manned, and even without
them, you would need to use energy to regulate temperature. Heat is not your friend when maintenance is
concerned, the colder everything is, the slower it decays, the warmer it is, the faster. Interstellar spaceships probably don’t need
much crew during the flight, they pretty much just drift along and at those kind of speeds,
you don’t really need to worry much about collisions with microscopic dust particles,
very thick armor can pretty much handle it, armor probably made of bulk cargo. For moving freight, you probably got pushed
up to speed by a laser and will get slowed down by one at the other end too, probably
ones bouncing the energy off you and back to collectors to recover a lot of that energy. That sort of case is almost ideal for automation,
and very simple automation, except for maintenance. Of course an AI would seem to make more sense
than thawing the crew out periodically to do maintenance but there’s a good chance
human-level or smarter AI will never be legal, or that its authority will be restricted,
it’s very dangerous and not really necessary. Now, if it’s regulated it means it might
be a thing banned in certain places, and some scifi stories have used that to suggest robots
would be allowed for mining in space but not on Earth, like in Isaac Asimov’s various
robot short stories. However, if you’re worried about AI rising
up against humanity, the one place you most definitely ban it is any place where it’s
far from people. Unlike explosives, it’s the kind of danger
you want to keep under your nose, where you can easily check on it, not running an autonomous
ship deep in the void of space that nobody sees for centuries at a time. If you have sophisticated AI that can outperform
humans at tasks like maintaining equipment, and which you are not utterly confident about
the trustworthiness of, the last thing any sane person would do is stick it in charge
of a ship full of repair robots, megatons of raw materials, an utter lack of supervision
for centuries, and a permission slip to dock deep inside your territory. Even if you do go fully automated, it’s
probably wise to go the Sleeper Ship route anyway, just keeping minimal automation online
most of the time, with a more sophisticated AI that wakes up briefly for scheduled maintenance
or emergencies. The whole point of AI at the human or higher
level is to enable them to be creative and adaptable, which means that the more time
it has to sit by itself thinking, the more likely it is engage in or adapt to some new
way of thinking. In general I’d be particularly worried about
what anyone in isolation will come up with too, not just an inhuman intelligence. We talked about cultures shifting on very
long voyages last time in the series, in the Ark of a Million Years. If you’ve got a really long voyage, there’s
a lot to be said about keeping the crew on ice as much as possible, and certainly the
passengers. That way it is your original crew showing
up, which won’t be the case otherwise, even if they are all biologically immortal and
don’t have any kids during the trip, they are still not really the same people as the
ones who left. I can send folks on a mission for a few years
and they will come back very different, push that up to centuries and that change will
be vastly larger. Now, it’s worth noting that most probably
the same technology that lets you freeze and thaw people is what’s needed to make someone
biologically immortal, and we’ll talk about why in a moment, but if that’s the case
you don’t need to freeze them to let them make the journey intact. You might still want to so that they aren’t
experiencing the trip, with all the potential boredom and mutation of mind that implies. Also probably the salary. We probably don’t have to pay colonists,
you would have to compensate freight crews I’d think, and you might can get away with
paying less if they are sleeping most of the way. Being the crew of a Sleeper Ship is either
an awesome experience or a particularly brutal form of torture, same as freezing someone
and waking them up centuries later. A popular, if bizarre, punishment in a lot
of science fiction. You’re essentially kicking someone ahead
to a time when their family and friends are dead and the culture they knew is radically
different, that’s presumably the punishment angle, but of course you’ve not in any way
rehabilitated them or otherwise punished them. And that’s a very subjective punishment,
many people would cheerfully pay money for a trip to the future, even a one-way trip,
and while I hate to generalize, there are people who don’t really care much about
their friends and family, and I suspect there’s a decent correlation between them and the
sorts who would be getting convicted of the sort of crimes heinous enough to be dumped
into carbonite over. Probably a thing to keep in mind when picking
crews too, while most who sign up for a century long trip as a popsicle are unlikely to be
monsters, you do need to consider the basic mindset of anyone willing to sever ties with
home forever. That’s less a concern for colonists, who
would often be taking their families with them and going off to build a new world, but
for a freighter it probably wouldn’t be about pioneering spirit or simply wanderlust,
since this isn’t going backpacking for a year in another country or enlisting for a
term with the military or signing on to crew a merchant ship to distant ports of call. Or rather it’s exactly that last one but
with very distant ports where you’re not coming home to find some changes and maybe
one or two friends or family members married, born, divorced, moved, or dead, for such voyages
even the short trips would be like leaving during the Renaissance and returning home
to the here and now. It is, in a sense, one way time travel. I don’t doubt you’d find many volunteers,
for the same reason I’d imagine they could sell their cargo too, and even with our current
population and screening out the mentally unstable, I’m sure I could find thousands
of volunteers and also thousands of people who would pay a fortune for a bottle of wine
grown on an alien planet, or even just a random rock. Your typical civilization capable of mundane
interstellar travel probably has a population many orders of magnitude higher to select
from, and to sell to. You could still crew the ships with families
as well, and after a bit the crew becomes your real family anyway, as you leapfrog ahead
down the centuries, and if someone decides to leave, odds are you’d find someone else
at that port who either wanted to try it out or who already has done it many times but
either changed ships or took a break from it for a while. You could easily get your own sub-culture
from this, something Alastair Reynolds works with in many of his novels, such as the Ultras
from the Revelation Space series, a group of mostly cyborgs who roam from system to
system and add a new braid to their hair for every voyage they make, or the various Shatterling
families from House of Suns, a bunch of clones who all meet up every couple hundred thousand
years to share experiences. They all take advantage of freezing or stasis
or simply relativistic time dilation to avoid experiencing all that voyage time, not because
they’d die otherwise, but because they worry about experiencing all that time. Again though, there’s that notion that you’d
freeze yourself to avoid dying of old age, but in reality this isn’t the case. You’re not asleep when you’re frozen,
you’re thoroughly dead, these are truly Tomb Ships, not a place where folks actually
sleep, and that probably is not a semantic difference. When we freeze someone they are obviously
dead now, but to wake them up we essentially have to reconstruct all their cells. We’re not trying to freeze them to avoid
cell destruction so we can just warm them up either. We freeze them so that destruction is rebuildable,
like carefully disassembling a house brick-by-brick while cataloging where each one was. That’s why the process is a lot more complex
than just dumping someone in a vat of liquid nitrogen and why modern methods usually only
bother with the head, we know we can’t thaw any of those folks out until we have the technology
to replace their body anyway. In theory, you can come up with ways to freeze
and thaw people that wouldn’t necessarily mandate you also had life extension technology. Such processes would likely involve genetically
re-engineering people or use some process more akin to the carbonite-treatment Han Solo
got in the Empire Strikes Back, or some equivalent to plastination, which we sometimes do to
biological samples or corpses, replace waters and lipids with polymers, though presumably
in a reversible fashion. With actual freezing you have to worry about
your cells exploding, so we could imagine some material essentially inserting itself
to carefully pad and protect the interior of every cell that could be purged later on. We could also genetically engineer ourselves
to have cellular repair mechanisms and antifreeze by default in our cells, much as some fish
in Antarctica, or some amphibians like the Alaskan Wood Frog. We could even modify our bodies to tolerate
a certain amount of dehydration, allowing ice crystals to form without causing cell
damage, as many insects do in order to overwinter. It’s not like there’s a lack of working
examples in nature we can copy, each of which offers distinct advantages. I should note that nature gives us a warning
about this too, hibernation strategies are very risky in nature, and are only ever employed
when there is no other viable survival strategy available. The same may apply to using this for space
travel. This concept though isn’t just limited to
making corpsicles, again an AI might be a sleeper crew by only booting up periodically,
and people who have gone the cyborg route might do the same, either through something
akin to suspended animation or by slowing down their subjective experience of time. Interestingly a cyborg might actually be someone
you could speak to quickly if they were frozen. If hypothermia is anything to go by you need
at least a day to bring someone safely back up from the lowest body core temperatures
anyone has survived, which were still well above freezing, let alone liquid nitrogen
temperatures, so waking anyone in under a day would seem unlikely and we could be talking
about weeks. On the other hand, some cyborg or transhuman
with a lot of mental augmentation, usually assumed to involve having your neurons replaced
or subsidized by various metal conductors, which typically conduct better the colder
you get, might be someone you could chat with while they were frozen. In fiction frozen crew members often get woken
up for an emergency, either the whole crew was on ice with an automated system to wake
them up if something occurred or someone with a special skill set gets woken because of
some unexpected event they’re best qualified for. In practice that could only really be done
if it was a long term kind of crisis. An example would be finding out your destination
system for a colony ship wasn’t what you expected so you wake the astrobiologist to
review the data on alternate planets you can divert to, a decision you likely have months
to decide about. It’s also worth considering that you might
not be shipping whole people, but just their heads. Most folks who get frozen these days just
do the their head, not the whole body, and while that’s often because they actually
died first of some ailment that would require a new body anyway, it’s unlikely to be a
sticking point. I’ve seriously considered cryo as opposed
to burial or cremation, and probably would do it one day, and I’d prefer my whole body
be frozen but I don’t really much care, and most folks I know who contemplate doing
it don’t seem to either. So it might not be a ship full of frozen bodies,
corpsicles, but just a bunch of frozen heads. I’ve also noticed most of us who are fine
with being frozen are generally more okay with the notion of being a cyborg too. Which would imply a decent chance any frozen
crew woken up for routine maintenance activities might just be activated, body or brain still
frozen but conscious and piloting a robot. To top this all off, as we mentioned earlier
in the series, there’s quite a lot of radioisotopes in the human body, part of the background
radiation we all get, only internally rather than from the actual background. This is minimal but stacks up over time, when
you’re frozen and nothing is regenerating damaged cells. It takes a few thousands years to get a lethal
dose, and you could presumably unfreeze people occasionally to get some regeneration and
cellular repair, during which a little healthy exercise repairing the ship would probably
help too. Though you could probably avoid this, or seriously
extend the timeline by feeding them for a while in advance with foods grown on materials
missing those isotopes, that would require them spend quite some time doing that, and
saving them time is sort of the point of freezing them. Interestingly there is some research that
indicates we might need a little radiation to be healthy too, so this might end up being
a careful balancing act. Obviously this all brings up why you would
use such a ship, as opposed to run one by uploaded minds, AI, or cyborgs, but just because
a technology is available, which it might not be, doesn’t mean everyone chooses to
use it. Also, let’s not overlook suspended animation
for trips too. As best as we can tell, putting people into
hibernation, with hydrogen sulphide gas for instance, really does lower their metabolism
and thus slow their aging too. You’re losing some life but not equal to
the time that’s passed, and you are saving on supplies and energy, which currently for
spaceflight is quite important. In this regard it matches the normal reason
for hibernation in nature, a dangerous and desperate survival strategy you only employ
because there are no alternatives. But that could be very handy for something
like deep space travel, where a mission might last a few years during which you’re trying
to conserve supplies, like heading out to the Oort Cloud to lasso a comet, or just a
routine freight drop. It’s quite likely, as we mentioned in both
Colonizing the Oort Cloud and Colonizing Neptune, that both the Kuiper Belt and Oort Cloud will
be heavily colonized and dependent on large, low cost, low frequency supply drops of fusion
fuel and presumably other trade goods of a non-perishable nature. Sticking the crew in suspended animation during
some big circuit run from a gas giant to hundreds of habitats where the crew goes into suspension
makes a lot of sense. They are not actually asleep though, if mimicking
animal hibernation or torpor, there’s no REM sleep, so presumably no dreams. Which is a pity in a way, as one might imagine
using mind augmentation to allow shared dream states or such, possibly to keep brain synapses
active. I suppose one might do that with our hypothetical
cyborgs who could still function mentally while frozen, if you wanted or needed to keep
them just a little awake, some very slow group simulation, maybe rehearsing for emergencies
or practicing colonization or whatever their end mission was, which might be an invasion
or something. So how would you crew such a ship if you’re
using these methods? You could have a crew who woke up in shifts,
say 1000 people for a 1000 year voyage, with each awake for a decade and ten people a shift. You could have one crew of 10 who were woken
every decade to do repairs, unless some emergency happened. You could have a generational crew, separate
from frozen passengers, the latter making the whole trip frozen while the crew lives
and breeds and dies and passes their responsibilities on to the next generation. This would make sense if you had a small but
decent chance of dying when frozen and thawed, especially if the risk rose cumulatively,
say 1% chance the first time you were frozen but 2% the second, 3% the third and so on,
I’m not sure why that would be the case, but it’s popular in fiction and one could
imagine a method of freezing and thawing that left you a bit more damaged and less likely
to survive each time. A thing to keep in mind about small crews
is that it’s easier for them to go nuts and easier for them to do damage if they do. You might be more likely to have a single
person go axe crazy out of 20 people rather than 2, but odds are it won’t be 10 times
more likely and they’re in a much better positions to do damage, they just have to
deal with one fellow crew member to have the run of the ship. So you probably need a lot of research to
find your sweet spot, with the minimum risk of someone going nuts from isolation, or just
life in general, and actually being able to do significant damage while they’re about
it. This also raises the point that a computer,
an AI, while a risk for going rogue itself might be less of a risk than a crewmember
doing so. Any crew or AI smart enough to deal with a
weird and unlikely event might be much more likely to go off the deep end than any of
those events are to occur. If you’ve had thousands of missions to draw
data off of and found there was only 1% chance of anything unexpected happening that a person
or AI could actually prevent or deal with, but a 2% chance a crewmember or AI would go
nuts and destroy the ship during the voyage, then you don’t have anyone awake for the
trip and just toss the dice. There’s a big caveat though, if you can
wake people up, and easily enough that you’re contemplating using this tech routinely, potentially
periodically to wake crew in shifts or for scheduled check ups, then someone can sneak
a device on board to wake them up at a time of their choosing. One can think of tons of reasons someone might
do that. A group that wanted their own colony, under
their own radical ideology, but couldn’t get funds or permission to do one, might sneak
such folks aboard to wake up at a secretly scheduled time for a coup or to kill some
of their fellow travelers. Potentially even converting it from a sleeper
ship to a generation ship, so they can expand their numbers, or the crew might kill off
their frozen passengers and become a generation ship. That could even happen accidentally, with
the cryo equipment breaking. Similarly some enemy nation or terrorist group
or doomsday cult might want to scuttle a colony ship, and sneak a saboteur onboard. We can also contemplate a virus that got the
AI mid-flight, causing it to blow up the ship or plot a new course. And of course this doesn’t only apply to
colony ships, there are tons of reasons to hijack or sabotage a freighter, it’s one
of the few ways you might be able to plausibly do space piracy. It’s usage also isn’t limited to fixing
problems during emergencies, freezing people is a good way of making escape pods for emergencies. Normally any pod to evacuate a damaged ship
would rapidly run out of air and food and energy long before it could be rescued, but
if it freezes you, centuries could pass before rescue and you’d be fine, and also experience
no dread waiting for rescue. Now we’ve talked about hibernation, freezing,
and the AI and cyborg routes, but what about the more classic scifi concept of a slow-time
pod that you just enter and time inside slows or stops until the timer outside dings? There isn’t much in known physics that permits
this, but it’s not actually banned either. We know two ways to slow down time, traveling
at close to the speed of light or creating a very high gravity potential around your
ship. Travelling at close to the speed of light
seemingly solves many of the problems we’ve been discussing here thanks to relativity. Everything from radioactive decay to the need
to even contemplate freezing and thawing, because travelling at close to light speed
is the ultimate stasis, basically slowing everything on board down to a fraction of
the time experienced by the outside universe. In theory, we could simply travel at a ludicrous
speed for a subjective day and a whole light year would have passed outside. At these speeds, not accounting for speeding
up or slowing down, we could wave goodbye to Earth and be in Alpha Centauri four subjective
days later. The rest of the universe would see us get
there over four years of travel time, but on board we would experience only four days. Our entire Milky Way galaxy could be crossed
from one end to the other in a quarter of a century of a person’s subjective lifetime
at these speeds. This is the pinnacle of life in the fast lane,
seeing the universe subjectively much faster than the speed of light allows. Of course, if you did that, over 100,000 years
will have passed for everyone else. That would be quite a homecoming if you swung
back to tell everyone about what you saw and experienced on your fantastic journey. Not only would everyone you know be long dead,
but you probably wouldn’t even recognise anything as being human because while you
would have been gone for a half a century of your time, nearly a quarter of a million
years would have passed back on Earth, making the sum total of Earth’s human history when
you left look like a blip in comparison. This is a well-worn sci-fi trope, though one
few do well. Alastair Reynolds Revelation Space series,
or his novel the House of Suns, are examples of it being done very well. While it’s attractive, unfortunately, there’s
a lot of handwavium involved. To get that kind of time dilation, you’d
have to be travelling at 99.99999% the speed of light. You’d need an insanely powerful drive not
only to get to that speed but to maintain that speed against all the drag the not-quite-vacuum
of space would be exerting on you. But of course every single atom would be hitting
your ship at that same speed, in other words with the energy of an atom bomb. And even the cosmic background radiation coming
at you from ahead would be so blue-shifted your ship would be ablated like you were being
bombarded with ultraviolet lasers. Remember too that as you approach light speed,
the amount of energy you need to increase speed goes up exponentially. You also have to accelerate that whole time
too, trying to maintain more than 1g of acceleration for months on end would be hard, and you need
to spend a year accelerating at 1g just to get near the speed of light. That’s part of what make inertial suppression
fields of interest in scifi, and indeed since relativity tells us gravity and acceleration
are the same thing, that is one plausible application of artificial gravity. Speaking of gravity, earlier, I mentioned
that other approach, creating a high gravitational potential around your ship. Even by the scales often contemplated on this
channel, natural gravity created by lots of mass, or dense energy technically, isn’t
very realistic as a means of ship stasis. Any black hole big enough to slow time significantly
for those near it, without shredding them to atoms from tidal forces, would be a supermassive
black hole. Considering even the normal stellar mass kind
weigh more than our sun, that’s an awful lot of dead weight to be pushing around, though
you might actually employ some trick like that for intergalactic travel, especially
to other superclusters. We’ll discuss options like that later on
in this series. We did mention artificial gravity though. We have a concept on this channel we call
Clarketech, in tribute to Arthur C. Clarke’s famous quote about any sufficiently advanced
technology being indistinguishable from magic, and it’s our catch-all term for technology
that doesn’t seem permitted under known science or for which there’s no theoretical
pathway at this time. Faster than Light Travel, FTL, and Artificial
Gravity, are two better known examples, though arguably even some of the stuff we’ve already
discussed today falls under the Clarketech banner. We don’t know what folks might come up with
in the future, some Clarketech for freezing time or creating closed timelike loops at
the macroscopic scale for instance, but artificial gravity is one pathway that might allow stasis
fields. Gravity slows time, and it’s tidal effects
rip people apart, so if we could make a classic flat uniform gravity floor like the ones so
typical in scifi, then stick one in the ceiling, there wouldn’t be any force of gravity between
those two plates but there should be a big gravitational potential, and if we kick the
power up time should slow down even more, do it enough and you’ve got stasis, or ultra-slow
time at least. Of course if you don’t do it right, you
might have different rates of timeflow in the pod, causing bits of you to age faster
than others. The effect would be similar to the tidal sheer
inside a black hole, except that it’s time sheer tearing you into spaghetti. We do also have some quantum effects that
play around with time but you’d have to be able to entangle a whole body of trillions
of trillions of atoms to use these, and we have a rough time entangling even a handful
of particles, essentially a similar technique to some of the teleportation methods we’ve
discussed in other episodes. That’s one last form of stasis too, teleporting
someone but not instantly, you hold them in a quantum suspended state and reassemble them
later. That’s very like the Seed and Data Ship
notions we’ll discuss next time in the series, that basically transport information not material. So there’s a lot of ways we might do a Sleeper
Ship and lots of advantages and disadvantages to each method. We’ve also discussed the various motivations
for doing each method, though one last motive incidentally would be stealth. There’s no true stealth in space but everything
is relative, and it’s a lot easier to hide a more compact and cold Sleeper Ship than
one warmed up and spacious enough for a crew and all their life support needs. On the whole though, odds are pretty good
the various technologies that will allow sleeper ships will also give us other options like
life extension, and a Methuselah Ship, another topic for another day, that would make Sleeper
Ships unnecessary for interstellar travel. But as we have seen, unnecessary doesn’t
always mean pointless or without advantages that might make it preferable. So I do think we will see these ships in the
future, even if in some unexpected roles. So as we move into our final episodes before
starting the new year, we’ll be doing some improvements and upgrades to the channel. Some of those will be with our website, IsaacArthur.net,
and it’s a good reminder how important a website is to any enterprise these days, but
they can be time consuming or expensive or both. You still need one, whether you’re a science
and education channel or growing a business, and that’s where Squarespace comes in. They have beautiful templates by world class-designers
that make it easy to create your own website, something that stands out, showcases your
work, and lets you get easy analytics about who is visiting. Squarespace’s aims to make it easy for you
to make a website on your own, but they also have 24/7 award winning customer service ready
to help you out. If you’d like to let Squarespace help you
make your dream website a reality, you can get 10% off by going to http://squarespace.com/isaacarthur
We talked a bit in this episode about artificial gravity fields, the kind of thing that would
let you make a Flat Earth. Next week we’ll be looking at building flat
planets but doing so inside known physics in Megastructures: Flat Earths. The week after that we’ll start December
off by asking how we might start off the real space age, in Kickstarting Space Industry. For alerts when those and other episodes come
out, make sure to subscribe to the channel, and hit the notification bell. And if you enjoyed this episode, hit the like
button and share it with others. Until next time, thanks for watching, and
have a Great Week!

100 thoughts on “Sleeper Ships

  • November 22, 2018 at 3:29 pm
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    Happy Thanksgiving everyone!

    Reply
  • November 26, 2018 at 10:33 am
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    I find literally every episode of your show incredible, including this one, but for some reason found it very hard to stay awake!

    Reply
  • November 26, 2018 at 3:45 pm
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    Can you make a video on spacejunk?

    Reply
  • November 26, 2018 at 9:17 pm
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    If I ever end up frozen, please inscribe this Lovecraft quote on my cryogenic storage dewar: "That is not dead which can eternal lie. And with strange aeons even death may die."

    Reply
  • November 26, 2018 at 10:44 pm
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    I KNEW Ludicrous speed was real!! 24:15

    Reply
  • November 27, 2018 at 1:58 am
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    What is the video at 6 minutes from?

    Reply
  • November 27, 2018 at 2:03 am
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    Man I have just found your channel and love what you do keep it up. I've done being watched about 6 videos! 🤣

    Reply
  • November 27, 2018 at 9:37 am
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    Amazing episode

    Reply
  • November 27, 2018 at 1:25 pm
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    not corpcicles but popskulls

    Reply
  • November 27, 2018 at 2:53 pm
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    Its Insight Landing Day! Lets Celebrate together Yay!

    https://www.youtube.com/watch?v=JqHg4qvb1JU

    Reply
  • November 27, 2018 at 11:41 pm
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    You know I actually find Isaac's voice fairly soothing even if he has a lisp or whatever it is. Doesn't bother me, just makes me think he from a diff part of the world. (haha, aren't we all?!)

    Reply
  • November 28, 2018 at 12:36 am
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    Isaac, do you have any insider info on Hades 9? Specifically when this beast is coming out? Or perhaps a beta date? Every time you show it on your channel, I get very jealous. I want to play it, it looks so fucking amazing!

    Reply
  • November 28, 2018 at 12:45 am
    Permalink

    We can only dream.

    Reply
  • November 28, 2018 at 12:50 am
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    ill say it , your gonna masterbate unless you got girls , and you need people that dont mind playing video games….as well as exercse

    all things no one ever talks about for long travel

    Reply
  • November 28, 2018 at 6:29 am
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    Awesome video! I have been waiting for you to cover this for a while now!
    also 18:40 AYY LMAO

    Reply
  • November 28, 2018 at 7:06 pm
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    A great vid Arthur, thanks. Hey, I was wondering if you could make a video about something you've mentioned briefly in this video regarding mind augmentation to allow shared dream states, just like in the movie inception. I've always wondered if this is really possible and how it can be achieved. Thanks once again and keep up the good work.

    Reply
  • November 29, 2018 at 1:55 am
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    I think enslaving AI to work for free without rest or anything will be illegal, or at least become illegal thanks to the same people like myself fighting for human and animal rights.
    We actually already did freeze and recover a rabbit brain successfully without any neurons being damaged, that's not quite near doing a human and there were chemicals involved that would cause serious permanent brain damage, but we're getting closer to a non-fatal time delay. I agree that we'll have life extension by then thanks to new medicine, printing organs, repairing DNA and stuff.

    Reply
  • November 29, 2018 at 4:44 am
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    Can't the BFR be a sleeper ship candidate?

    Reply
  • November 29, 2018 at 7:33 am
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    Cheapest Fastest Star Travel possible – How about two low tech Civilizations that invent DNA printers and radio designs and memories at Light Speed between star systems. No actual spaceships involved, no Sleeper or Generation Ships. In a Galaxy with a Federation of planets many races might be able to live and explore between systems without ever actually having to travel between star systems. Or if we are the First.. beam a message with designs and personality that can be recovered by a New Civilization born millions of years hence. Encyclopedia Galactica might be a form of Space or Time Travel for sheparding, or conquering Future Civilizations. I suppose as some Stars pass other Stars naturally they might launch low tech slow boats to colonize and extend their civilizations like strings of sphagetti looping around the galaxy. As more and more become these migratory china boats on the ocean of the Star lanes.. agreements to print and "relive" different members of different races from different spacial Parts of the Galaxy or different Times of the Galaxy to create a complex multi-era colonial dynasty as an outpost dotting the landscape might come to also explain Fermi's Paradox. Not needing faster than light, or high tech the goal might be in these complex civilizations with Spatial and Temporal dimensions.. to live off the landscape.. and not build huge wasteful dynamic singular civilizations.. but to simply exist as part of the whole.. more like a microbial colony on a Galactic scale.. newbie races and civilizations might be watched like the Borg watching a potential meal.. for future cultivation or exploitation.. or integration.. and adoption "after" it has passed the trials and tribulations of its nursery days. – truer civilization might be these low tech "slow" tech microbial colonies dotting various solar systems, communicating like individual Neurons in a big brain, thinking and working on different topics and interests.. with their own local challenges.. but also contributing to evolution of the galatic whole.. like a galactic brain. Some might send out von neuman probes.. or outgrow the need for them.. as they discover their local space already colonized.. some zones might be very old like a very old neighborhood with rigid rules.. or decaying from atrophy pursuing various avenues that leads to them being partitioned from the whole.. or "sleeping" while various parts of the galaxy go through renovation.. or damage control.. only to be repaired by the arrival or arising of a new civilization in that particular corner of galactic neighborhood. It may be far less nefarious than conspiracy would lead us to believe.. but simply the messy bureaucracy of galactic life. – Day the Earth Stood Still might be very prophetic, with the arrival of the first "visitors" by DNA printer who act as liaisons/ambassadors/military or legal judicial representatives who come to deliver the local rules and regulations with gateways and plans to technological valhalla… if not conquerors.. benign "visitors" might think nothing of disassembling themselves into goo.. should we be unfriendly.. or too immature to 'join up' .. on first inspection up close… they might come again in a few thousand or million years… or setup Monolith like Embassy's that go to sleep for millennia.. waiting for us to come round.

    Reply
  • November 30, 2018 at 3:14 am
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    Will there be a premium charged to would-be full-body freezees just after the holidays?

    Reply
  • November 30, 2018 at 8:25 am
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    All the replies here regarding the Passengers film (sleeper ship hibernation failure) with good ideas shows the plot was stupid anyway if there was one in the first place (they just glued bits together). Maybe a few waiting staff hanging around and when he woke they sat him down and broke the news that he as a Human was redundant (starting with their refusing his sexual demands). Then the plot of him sorting that out would be interesting (unlike most films where both sides just blast each other to bits in sensless rounds of talke that!).

    Reply
  • November 30, 2018 at 10:11 pm
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    Thinking about that "months of acceleration" bit for going high percentages of light I have to ask months by who's frame of reference? If time is slowing so that years become centuries how does a ships engines accelerate it if those engines themselves are operating a hundred times slower? Unless that is why you need exponentially more energy to do so, as might be obvious my physics knowledge is not good when it goes to the weirdness realms of theoretical physics.

    Reply
  • November 30, 2018 at 11:02 pm
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    was thinking about it what if people were mummified because people back then thought that maybe in the future we would be able to bring them back from the dead and what if cryo is just the modern day version of that

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  • December 1, 2018 at 11:20 pm
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    24:15 LUDICROUS SPEED ENGAGE!!!!!!

    Reply
  • December 2, 2018 at 12:45 pm
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    You Issac happy thanksgiving buddy.I want to tell you since I discovered your
    Channel I have been so happy. When ever I get a notification from you I literally jump out of my skin I’m so excited. Keep up
    The awesome work bud.

    Reply
  • December 3, 2018 at 12:23 am
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    People have left home, severing ties with friends and family forever. Even into the 1800's immigrants leaving the Old World for the New usually left, knowing they would never return or even have contact with those they left behind

    Reply
  • December 3, 2018 at 5:27 am
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    16:00 If what we are is just memories, could we save that data to some kind of storage device, like a hard drive, and a machine that could build an entirely new body from local organic matter, then download the memories into that body.
    You could even tailor the body to that environment. In this way you could ship as many people as needed in nothing more than a hard drive.
    Hell, in theory, you could even make more than one copy of each individual.
    The people being uploaded may not even need to die. Just upload an engineer, a medical doctor, some scientists and laborers (say a welder, construction worker, mechanic excreta.) As a welder though, I'm not sure I'd want to work with 20 versions of myself.

    Reply
  • December 3, 2018 at 9:29 am
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    24:40 Until we unlock the mass effect relays

    Reply
  • December 3, 2018 at 10:31 am
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    Artificial Gravety and FTL is only not known concepts to you. sorry to say. Others have there very well knowledge, only supressed or ignored.

    Reply
  • December 3, 2018 at 6:55 pm
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    Thank you for this.

    Reply
  • December 3, 2018 at 10:23 pm
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    transporting ships full of heads :)) ….. come on…we are not leaving the solar system if we want to take our bodies with us. Why do we need it anyway? We wont find an identical earth like planet, which means that we have to adapt regardless of our destination. Upload consciousness, travel, build new body with adaptations, download consciousness, done. And while you're uploaded you can hang out in some VR world..

    Reply
  • December 4, 2018 at 4:30 am
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    Wonderful channel and amazing videos. But can the dictator please work on removing that 'r' speech impediment? It has to be resolvable. Drives me nuts, I have to unsubscribe for now. It's my loss but I really can't stand it.

    Reply
  • December 7, 2018 at 2:33 pm
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    it is impossible to feed people a diet that does not contain radioisotopes. There will always be K-40 und Uranium decay products in it. It is also not necessary, as the main problem during a centuries-long trip is the external radiation received during the trip. If you just assume an (unrealistic) very low estimate of 2µSv/h dose rate, you would receive 1.75 Sv in a hundred years. The real dose is probably at least ten times that (NASA estimate for 360 day Mars return trip alone is 0.7 Sv).

    Reply
  • December 8, 2018 at 12:16 am
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    Did you just say that huffing farts can knock a person out? Please elaborate on the subject of Hydrogen Sulphide in Suspended Amimation

    Reply
  • December 11, 2018 at 5:31 am
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    sleep, mmmm, zzzz

    Reply
  • December 11, 2018 at 9:50 am
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    My concern for such a voyage is that they are going to get bombarded with lots, and lots of radiation. That causes a host of problems both for the crew/passengers and any descendants they might have. The only preventative is lots of mass between their bodies and the outside.

    Reply
  • December 12, 2018 at 12:24 pm
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    Gives new meaning to "sleeping around"……

    But not to my ex Girl Friends…..

    NOT even gravitational waves come out of those BlackHoles….

    Reply
  • December 13, 2018 at 8:59 pm
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    people in the Nightflyers also went crazy. i suppose they could use suspended animation to prevent that sort of disaster.

    Reply
  • December 14, 2018 at 1:04 am
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    What kind of salary can you pay someone in a post scarcity society?

    Reply
  • December 14, 2018 at 2:44 am
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    Best novel on the concept of freezing/thawing crewmembers periodically: "The Freeze-Frame Revolution" by Peter Watts

    Reply
  • December 14, 2018 at 2:48 am
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    I'm still not sure there is any advantage in colonizing Uranus or Neptune or the Oort belt. We don't really need any outpost there, especially for interstellar travel. Better launch from a spot closer to the Sun where energy is aplenty.

    Reply
  • December 15, 2018 at 9:25 am
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    I hate the revised music. It sounds like an elevator. Why did you change?

    Reply
  • December 19, 2018 at 9:40 pm
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    1:48
    spinning weed plants
    ensure supply of pot for the arrival celebration

    Reply
  • December 26, 2018 at 11:22 pm
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    Could a decently sized black hole be used both as an energy source and a shield as well as a way to regenerate some of the energy lost to the vacuum drag in an extreme relativistic ship? In fact you would be feeding it a lot of extra energy in form of matter on your path.

    Reply
  • December 28, 2018 at 1:29 pm
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    I can't believe you're still thinking about money…! We will never evolve into an interstellar civilization if we don't evolve past money first… The first step to catapult us into the future will be to get rid of the financial elite who have enslaved humanity with money by brainwashing us since birth that we need money to live on this planet… Please Isaac, get familiar with The Venus Project, it is our only hope to evolve into a peaceful & technological future!

    Reply
  • January 1, 2019 at 9:10 am
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    The AI could be reset to factory defaults frequently. Every day could be it's first day on the job.

    Reply
  • January 1, 2019 at 9:33 am
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    For interstellar travel if FTL proves impossible, I would imagine the digital preservation of neural networks with either the operation of android avatars by simulated consciousness or the bioprinting of new organic bodies when needed. This also allows for a simulated digital crew to monitor the ships status and decide which options to take.

    Note, presumably you mentioned hydrogen sulfide to reference Roth's work on mice hibernation. First, there's no evidence that hibernation slows or stops aging, Roth continued with an analog which I believe was Sodium Sulfide but unfortunately with little success and lowering our body temperature subjects us to fungal attacks, never mind genetic degradation to cosmic radiation so hibernation may be of little use in interstellar travel.

    Reply
  • January 1, 2019 at 7:14 pm
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    Sleeper ships and time warping tech make eachother unnecessary. Yet you still need one or the other. XD

    Reply
  • January 3, 2019 at 8:29 am
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    There is a movie, penumbra, that covers the negatives of doing this, it's pretty good.

    Reply
  • January 4, 2019 at 7:14 am
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    Wow. The whole "people who want to be frozen probably have a lot in common with criminals" speculation is pretty shitty of you.

    Reply
  • January 4, 2019 at 11:30 pm
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    I’ve had numerous personal and professional interactions where the potential problem of “space boredom” have been addressed. Assuming that any ship large enough to transport a fledgling colony to another planet and support the colony until it becomes self-supporting, I cannot see where “boredom” would become any more of a problem than we see in modern life. If anything it would be less of a problem.

    Obviously each colonist would double as crew members and operating and maintaining a vehicle that large would keep one occupied the majority of one’s “awake hours.” With enough money one can build some extremely reliable systems. But even ultra high rel systems require preventive maintenance. And built in multiple levels of redundancy doesn’t imply that you leave the broken system broken because there’s three duplicate ones picking up the slack.

    If you want a good example of something that employs high reliability engineering and construction as well as redundancy, take a look at a US Navy ballistic missile submarine. A day on a boomer is 18 hours long. You spend 6 hours taking your turn running it. You spend 6 hours fixing it or addressing tasks meant to keep something from breaking, and you have 6 hours to sleep, shower, read, etc. I would expect that it gets old very quickly, but not from boredom.

    Take that same submarine and enlarge it 20000 times…or more. Have artificial daylight, parks with real grass, streams and ponds, I could go on ad infinitum. One could take a week’s vacation from duty and go on holiday to the other side of the ship. Or go fishing or swimming. I think it’s obvious where I’m going with this. In summary, I don’t think boredom would be an issue.

    Reply
  • January 10, 2019 at 11:14 pm
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    Thanks for the book recomendations by Alastair Reynolds – I have bought House of Suns on Audible

    Reply
  • January 12, 2019 at 2:38 am
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    I disagree with freezing people would kill them.  This is old tech. Future tech would take advantage of the tricks nature has figured out. There is bacteria that has survived being frozen for 10,000 years.    I would expect people could be genetically modified to survive freezing like the wood frog.

    Reply
  • January 12, 2019 at 8:15 pm
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    the fuck is wrong with your accent

    take some fucking english lessons

    Reply
  • January 14, 2019 at 9:59 pm
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    Only immature child cultures believe they can take the host form with them by travel through space-time. The only means of populating a Higgs constrained universe like this one is via controlled instantiation of the individual position-of-view (POV). This is a controlled version of the natural instantiation that nature implements to put you where you are right now. Read: https://www.amazon.com/dp/B07JHFDLSC

    Reply
  • January 17, 2019 at 2:28 am
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    I'm guessing english isn't your 1st language.

    Reply
  • January 17, 2019 at 10:15 am
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    I can think of little more morbid than a alien ship full of alien heads in ice with a crazy AI suddenly appearing in our system. Aliens.

    Reply
  • January 19, 2019 at 8:21 pm
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    For those who want evidence of something else, here it is: https://www.youtube.com/watch?v=3iKFYv05HNM

    Reply
  • January 19, 2019 at 9:35 pm
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    I was purposefully, partly frozen to death as a 10month old to have major heart surgery done to me; so it wouldn't be a completely new experience for me!?!? >XD

    Reply
  • January 22, 2019 at 12:24 am
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    Merge with AI, abandon monetary systems and develop warp drives, problems solved.

    Reply
  • January 23, 2019 at 8:45 am
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    i would sell everything i own to get a trip 100's of years into the future then put about £10,000 into a savings bond and let it grow over hundreds of years then not only will i be in a much more advanced time but ill still have money to buy a house and stuff

    Reply
  • February 3, 2019 at 6:17 am
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    I would give humanity too AI

    Reply
  • February 4, 2019 at 3:27 am
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    18:40 Sneaky, Isaac.

    Reply
  • February 8, 2019 at 6:15 pm
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    first ships out will be no frills

    Reply
  • February 8, 2019 at 9:53 pm
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    Everyone needs to watch this channel's videos so they can learn fancy scientific terms – like corpsicles!

    Reply
  • February 11, 2019 at 2:03 pm
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    I just had a thought what if right now we are all asleep on a sleeper ship heading to a new star and we are using a simulation life to keep us sane as we make the trip to the new star……….

    Reply
  • February 16, 2019 at 1:04 pm
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    We are not going to visit the distant stars in biologic form. It does not make any sense at all. As our technology evolve we will be able to transfer our minds to a robot and be able to travel anywhere. Time will not matter any longer.

    Reply
  • February 21, 2019 at 5:35 am
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    Hahahaaa…! Dropping ice in a tube with a little Han Solo figure… had to pause the video there to laugh for a while!

    Reply
  • February 25, 2019 at 3:27 pm
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    It is the year 2445.
    After nearly 300 years of travel, our sleeper ship is approaching it's destination.
    A robotic voice states: "Initiating wake-up sequence"
    I reply: "Just 5 more minutes"

    Reply
  • March 1, 2019 at 12:04 am
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    If a zero-time stasis field is turned on & off from the inside, as they appear to be in a lot of scifi, how would you ever be able to turn the thing off?

    Reply
  • March 1, 2019 at 1:10 am
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    10:57 Activates my google home. You go on to say "A group a cyborgs" and it's paying attention. How CREEPY!

    Reply
  • March 5, 2019 at 2:07 am
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    Sleep ship by aliens coming to terraform earth seen 100's million years ago. And we become the surprise at the end of the trip.

    Reply
  • March 11, 2019 at 7:29 am
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    Well most likely be stuck with sleeper ships it seems we are forever bound to far far less then light speed.

    Reply
  • March 12, 2019 at 4:16 am
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    People really don't go crazy very often, and the vast majority of people don't get violent tendencies when in isolation for a very long time. Having a single other person around drastically lowers this rate again. Up this to 10 people and the rate is fuck all. We're talking about a rate around a percent of a percent.

    Simply put, isolation sickness doesn't work like that.

    Reply
  • April 12, 2019 at 7:52 pm
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    IT WONT BE 4 DAYS FOR YOU IF U TRAVEL AT THE SPEED OF LIGHT , A DISTANCE OF 4 LIGHT YEARS WILL BE AN INSTANT FOR YOU, COZ TIME WILL STOP ALL TOGETHER FROM YOUR PRESPECTIVE

    Reply
  • April 17, 2019 at 4:54 am
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    8:20 This is the reality of globalism… cultures being forced on each other….also not sure why I have to be stuck with the current state of technology and connectivity…

    Reply
  • April 21, 2019 at 2:31 am
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    Huh… I can freeze my head if I die? Gonna have to make that part of my will O.O

    Cyborg body here I come!

    Reply
  • April 26, 2019 at 9:30 pm
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    I was wondering.. Won't most interior decay over time in some form during travel? Wirering etc.

    Reply
  • May 10, 2019 at 6:56 am
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    Disasters approaches earth. Solution download as many peoples brains as possible along with a digit DNA sample. Put each data set on an individual space capable flash drive and jettison into space. Just imagine where/when you might wake up.
    Data ships might be small; really really small.

    Reply
  • May 23, 2019 at 2:32 am
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    I do love me some Sleeperships, always have.

    Reply
  • June 1, 2019 at 12:11 pm
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    our ewrlyist space ships twraveld fwaster then vehicle on ewrth

    Reply
  • June 9, 2019 at 1:05 am
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    Being frozen for centuries at a time! It be awesome watching cultures even species evolve man!

    Reply
  • June 15, 2019 at 6:49 pm
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    if you think about it these ships are likely to need sex workers or a lot of tissues

    Reply
  • June 26, 2019 at 3:14 pm
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    Your channel is so interesting!!

    Reply
  • July 24, 2019 at 7:20 pm
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    This doesn't make any practical sense, if something is being built and they need materials, it would take a VERY long time for a portion of the materials to get there (dependant on distance)

    Reply
  • July 27, 2019 at 10:15 am
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    Passengers…..deep or dumb?
    Jk its space poop.

    Reply
  • July 30, 2019 at 5:12 pm
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    the pharaohs and ancient Egyptians created sarcophagi. How did they come up with the concept? Did travellers come by in stasis in there own technologically bejewelled sleep chambers? Where did the idea of the pyramid come from? Makes you wonder and the there Gods with a dog face?

    Reply
  • August 6, 2019 at 1:03 am
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    Everybody knows you'll go to plaid if you hit a ludicrous speed…

    Reply
  • August 12, 2019 at 6:27 pm
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    This channel makes so many wild assumptions, big leaps and weird directions…. And then bases the next eventuality on top of them. So the further along they go, the more unlikely the outcome is.

    Reply
  • August 14, 2019 at 10:05 am
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    Best youtuber hands down !

    Reply
  • August 16, 2019 at 4:31 am
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    No real-life Cylons, please!

    Reply
  • August 17, 2019 at 9:56 pm
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    Centuries? Even for a few decades, I smell budget cuts.

    Reply
  • August 22, 2019 at 4:43 pm
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    Do they get time and a half for overtime?

    Reply
  • August 22, 2019 at 5:00 pm
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    You program your ship for a twenty light year journey to Alpha. You awake to find yourself back where you started because of interstellar shift or another twenty years away due to universe expansion. Need a crew? Advertise it as a cruise with all expenses paid. LOL…. Oh, I refuse to go if Ripley is on the crew.

    Reply
  • August 26, 2019 at 12:47 am
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    Only Bots would be able to make it too another star.

    Reply
  • August 26, 2019 at 8:28 am
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    sleeper ships?????you must be dreaming,,,scifi..not real….

    Reply
  • September 1, 2019 at 9:43 pm
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    Remember those tic tac UFO’s seen in the ‘ Nimitz encounters ‘
    Well turns out the Navy secured quite e few patents some years back all basically describing a craft with some sort of electromagnetic drive , field drive . If they have actually cracked it all bets are off for space travel . The patents covered a triangular and tic tac shaped crafts . The theory is seemingly sound the engineering and materials thought to be out of our grasp but not impossible . The biggest hurdle would be wtf have they got as a power plant as the power needed is immense . Nothing on power was patented . Well not right along with everything else .
    Food for thought eh !

    Reply
  • September 2, 2019 at 9:10 pm
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    Question: where do space pirates find test subjects and sex slaves?
    Awnser: sleeper ships

    Reply
  • October 15, 2019 at 7:13 pm
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    Regarding the AI going rogue, it would be due to bad design, because there are many ways to keep it in check.
    Even if it is based on a neural network, we can find a way to ''freeze'' its state once it is satisfactory, so it does not evolve anymore,
    but just performs as needed. Maybe by turning it into a hardware integrated circuit.
    Other option : having a potentially ''smart'' software AI, capable of evolution, but erasing it regularly, by rebooting its host, for example.
    Then it would be spawned again by loading its read-only template. The operations of reboot/erase/reload would be performed by
    a separate dumb system that could not be hacked, corrupted or persuaded.
    Usually the problem is not Artificial Intelligence, but rather Natural Stupidity.

    Reply
  • November 3, 2019 at 7:28 am
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    Oh Buck Rogers….you still have one of the best opening theme music ever !

    Reply

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