Floating

16 posts / 0 new

Sun, 12/24/2017 - 08:46

nineteenthly

Floating

After a recent request, I got to thinking about the issue of buoyancy in air, and I think I may have changed my mind slightly about it. This is how it goes:

An inflated adult could only become buoyant if they were inflated with a very large volume of a lighter than air gas, probably either hydrogen or helium. Assuming they weigh 60 kg, they would have to become a sphere more than fifteen feet across for this to work, even assuming they are filled with a gas of zero density. It would be compressed anyway, meaning it would be denser.

Ways of making it work would include weird physics, e.g. substances with negative mass or weight; very low gravity (it would work on Enceladus with our atmospheric pressure); much higher external pressure (meaning less inflation) or underwater.

And yes, of course this is fantasy, so who cares? Well, me. I can't find this interesting or exciting unless I can kind of push myself into believing it, at least temporarily.

However, I've just realised that although there's no way you can have actual buoyancy without taking it a long way from possibility, you can have something rather similar.

Going back to our 60 kg person, assuming them to be 5 foot 4 and inflated into a sphere with a normal one foot diameter head, that's a sphere with a radius of 65 cm and a volume of 1150 litres. Now, that isn't lighter than air but it is, assuming zero density for the gas, only 5% of water. That's incredibly light! Clearly it would be offset by the density of the gas inside, but still not by much. If it was air at sea level pressure it would add less than 1.5 kg to the weight.

Cross-sectional area of such a sphere is around 1.3 metres. Therefore, whereas you couldn't get lighter than air, what you could definitely get is blown along by a fairly light wind (even force 7 gales can blow ordinary people over) and you could probably get falling slowly and harmlessly from quite a height. Not sure about how high anyway.

Just thought I'd share. Sorry if it's not quite up your street but I hope it interests someone.

http://www.youtube.com/user/nineteenthly

Sun, 12/24/2017 - 12:02

leonofpenance

I actually agree with you on this subject. I like a sense of realism in this fantasy

Mon, 12/25/2017 - 09:09

Lopni

Indeed, inventing some kind of (any kind of!) imaginary physics is an absolute prerequisite for any game-making, be it Game Maker or cardboard tabletop, Excel or pencil and paper

For instance, take synthesis of proteins in cells. Imagine in a fantasy universe they've taught their cells to produce matter that just happens to be gas in room conditions using the very same biosythesis, and then exploit the same gas as a source of chemicals for cell division and replication.

Substituting real world "protein biosynthesis" with simply "biosynthesis" is a complete fantasy, not less than clean popping or safe deflation. But it's much more specific because it lets you put - and answer! - questions like

- how fast inflation and deflation is given we know in sufficient detail what happens during translations, transcriptions and folding

- which gases could actually be inside the inflatee given we know what our body is made of

^_^

Tue, 12/26/2017 - 01:57

nineteenthly

I like the idea of gas inside the cells, perhaps as vacuoles. I can also easily see that it might happen in that there are biochemical processes which create gases, the obvious ones being aerobic respiration and photosynthesis, but there are others such as the production of oxygen from hydrogen peroxide via catalase, which I've long thought I would at some point include in a story.

Another thought I've had, inspired by Pneumaticchick's balloon girls, is that there could be almost jellyfish-like humanoid beings who are routinely filled with gas as part of their biology with just the skin performing all the biological functions, which means that with hydrogen, they could actually genuinely be lighter than air. One scenario I came up with was that they were a slave race called the Aurelians who were deflated for storage and one of their cargo ships accidentally crashed on Earth, as with 'Alien Nation' and 'District 9', or that they were made in a factory. This would also mean clean popping would be possible.

Speed of inflation is a difficult one, isn't it? The maths is really complicated for gases, though not for liquids.

Just on gases inside the inflatee, I once came across someone's idea that all the oxygen in someone's body became part of the gas inflating them, which for me didn't work because it would mean their body was no longer made of the same substances.

A little knowledge becomes a disappointing thing in these circumstances if you can't find a way to ignore it!

http://www.youtube.com/user/nineteenthly

Tue, 12/26/2017 - 10:37

airtankgirl5

I like the idea of the Aurelians. Obviously I think they should be able to cross breed with humans ;)

Tue, 12/26/2017 - 16:00

(Reply to #5) #6

leonofpenance

That' the basics of the main character of my story: born from crossbreeding and scientific mutation experimentation

Tue, 12/26/2017 - 10:45

SvenS

I really have to get back to working on my big story project - it has fun with this theme all throughout it.

Wed, 12/27/2017 - 02:26

nineteenthly

Airtankgirl, how about there are Aurelians among us but they don't know they're not normal human beings, and people accidentally discover themselves to be one day? Say they go for a vaccination and it causes them to deflate, they have to be inflated again and it goes too far?

I have an idea based on catalase I've been itching to write for years. It can release five litres of oxygen from two teaspoonfuls (10 ml) of hydrogen peroxide, and it really exists. The problem is that pure hydrogen peroxide is nasty stuff if it comes in contact with living matter, which is why catalase exists in the first place.

http://www.youtube.com/user/nineteenthly

Wed, 12/27/2017 - 07:15

(Reply to #8) #9

hfilled

Perhaps a neutalizing agent to protect living tissue?

Fri, 12/29/2017 - 03:17

(Reply to #10) #10

nineteenthly

You'll see when I've written it. I have plans.

http://www.youtube.com/user/nineteenthly

Fri, 12/29/2017 - 14:02

(Reply to #8) #11

airtankgirl5

Yes, the notion of not knowing if one is even an Auriellian descendent has obvious appeal. Really this has a lot of meta potential, this is how ALL inflation fiction came about :)

Fri, 12/29/2017 - 21:37

(Reply to #8) #12

Margeret Moonlught

This is shaping up to be the story of the season

Fuck dude I'm legit excited about this

BI.org’s very own metamorphic incomprehensible memetic fractal entity

Wed, 12/27/2017 - 06:02

#13

Margeret Moonlught

I for one welcome our new balloon alien overlords.

BI.org’s very own metamorphic incomprehensible memetic fractal entity

Wed, 12/27/2017 - 08:37

#14

nineteenthly

ROFL! I was thinking of them more as slaves but fine! The balloons are on top now?

I know where I'm going with the catalase. You shall see (if I ever get round to writing it).

http://www.youtube.com/user/nineteenthly

Fri, 12/29/2017 - 02:36

#15

JackTaylor

This is really interetsing to know.

Fri, 12/29/2017 - 03:16

#16

nineteenthly

Thanks. It's surprising I haven't thought of it before but it really makes sense. Considering that people can in normal circumstances find it hard to walk against the wind and ultimately get blown over by it, it stands to reason that if they were inflated, the threshold at which it would occur would get lower, and falling is equivalent to doing so while holding an enormous air balloon or parachute of that side, so it would in fact make a difference. The same principle applies to people wearing inflated suits, although I'm not about to recommend that anyone jumps off a roof wearing one!

I think it's the dogma of "you cannot make someone lighter than air" that blinded me to the possibility.

Another thought is that hydrogen, helium and a few other nastier gases could provide buoyancy to some internal organs even though they don't make the whole body lighter. So you could have kind of floating innards! Sorry if that's a bit ew!

http://www.youtube.com/user/nineteenthly

Floating

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