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Why didn't the Romans have hot air balloons?

chronopause.com

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Re: Why didn't the Romans have hot air balloons?

#11

Post by iwwr »

Fascinating article, with just one quip I'd have:

Plutonium-238, the material in nuclear batteries is very different from Plutonium-239, a material for nuclear weapons. There is great stigma against Plutonium, but mainly because of Pu-239. If you remember some of the news around the launch of the Cassini probe, there was opposition because of the Pu-238 pellet powering the RTG.

Compared to Pu-239, Pu-238 is non-fissile and also produces a lot of heat (which is the point, really). Pu-238 poses almost no proliferation risk. Even the radioactivity is in the form of alpha radiation, which needs very little shielding (hardly even penetrating the skin). The only problem with Pu-238 right now is that it's very expensive to produce and also very scarce. If Pu-238 were abundant, it could find many applications and pose very little security risk; building a dirty bomb out of it won't really work (as a matter a fact, neither making one out of Pu-239).

In general, our civilization has an irrational fear of nuclear energy. Even more egregious since there is a variant of nuclear technology that's almost completely proliferation-free, namely the thorium cycle.

Re: Why didn't the Romans have hot air balloons?

#12

Post by Charuru »

jasonkester wrote: post #10

In hindsight, it seems clear that if humanity had decided in 1939 to colonize space, instead of expending ~$17 trillion and ~74 million human lives on war and destruction, we would have reached the moon in a robust and durable way by no later than the mid-1950s He kinda gives away the answer to this earlier in the article, while explaining why the cool edge-case technologies the Romans had never took off: the truth i…

Are you saying that war increases technological growth? That's crappy pop-history that's largely been discredited. Competition invites advancement, blowing up your competitors does nothing.

Re: Why didn't the Romans have hot air balloons?

#14

Post by JanezStupar »

Charuru wrote: post #12
jasonkester wrote: post #10

In hindsight, it seems clear that if humanity had decided in 1939 to colonize space, instead of expending ~$17 trillion and ~74 million human lives on war and destruction, we would have reached the moon in a robust and durable way by no later than the mid-1950s He kinda gives away the answer to this earlier in the article, while explaining why the cool edge-case technologies the Romans had never took off: the truth i…

Are you saying that war increases technological growth? That's crappy pop-history that's largely been discredited. Competition invites advancement, blowing up your competitors does nothing.

So what you're saying that intense competition between national armies is not the kind of competition that humans are willing to stake almost anything and commit endless resources on?

War itself may not increase technological growth. But preparations for war certainly do. And please show me another competition that has yielded lets say 50% of technological advances that various arms races have?

Sadly when human develops new kind of tech and is looking for money to get it widespread - the first and deciding question is: "Can it be used as a weapon?"

Think of the nuclear bunker gap!

Re: Why didn't the Romans have hot air balloons?

#15

Post by nazgulnarsil »

philwelch wrote: post #4
aoeuid wrote: post #3

Earlier quoted context omitted.

The guy who wrote this post used to be president of Alcor ( http://alcor.org ), one of the two cryonics organizations in the US. Cryonics is in fact certainly a procedure where people will definitely die if they don't get it, particularly because it can only be done after 'legal death'. Its efficacy can't be established conclusively right now, but it's certainly more likely you'll be revived if you undergo cryopreser…

There's a genuine plausibility difference between inventing new surgical techniques and freezing corpses in liquid nitrogen hoping that future generations will resurrect them. In terms of the high certain burden on the rest of society (in terms of expending resources, denying others the use of one's organs, denying the use of one's remains for medical research or education, etc.) and the very outside chance that one…

only if you abuse the abstraction of language to impose restrictions on reality that don't exist. people who would have been declared dead 50 years ago are now resuscitated routinely.

Re: Why didn't the Romans have hot air balloons?

#16

Post by daniel-cussen »

iwwr wrote: post #11

Fascinating article, with just one quip I'd have: Plutonium-238, the material in nuclear batteries is very different from Plutonium-239, a material for nuclear weapons. There is great stigma against Plutonium, but mainly because of Pu-239. If you remember some of the news around the launch of the Cassini probe, there was opposition because of the Pu-238 pellet powering the RTG. Compared to Pu-239, Pu-238 is non-fissi…

Chile is already moving toward building the first thorium nuclear reactors: http://diario.elmercurio.cl/detalle/index.asp?id={183364cc-d...

Re: Why didn't the Romans have hot air balloons?

#18

Post by Tuna-Fish »

nitrogen wrote: post #8

The informative first half of the article was fascinating, but it slowly deteriorated from there as I read the argumentative second half. In my view, things took a drastic turn for the worse around this sentence: Mature genetic engineering, nanotechnology, strong artificial intelligence, and quantum computing, to name but a few, each hold many times the potential for systemic harm to, or destruction of our civilizati…

With nuclear tech, humans have to be the ones pushing the buttons, making pure accidents quite unlikely. If moore's law holds and we make a strong AI, it might theoretically be possible for it to "go FOOM" -- use most of it's thinking power to make itself exponentially smarter, hitting the ultimate physical limits of computing in a relatively short time. If that happens, and the ultimate physical limits of computing are sufficiently far away, the entire human race no longer has any say on it's future -- whatever happens from then on is decided by a singleton entity.

A good overview of the arguments from both sides can be found from the Hanson - Yudkowsky debate on the subject: http://wiki.lesswrong.com/wiki/The_Hanson-Yudkowsky_AI-Foom_...

Disclaimer: I have not studied the issue deeply enough to be on either side.

Re: Why didn't the Romans have hot air balloons?

#19

Post by olalonde »

nitrogen wrote: post #8

The informative first half of the article was fascinating, but it slowly deteriorated from there as I read the argumentative second half. In my view, things took a drastic turn for the worse around this sentence: Mature genetic engineering, nanotechnology, strong artificial intelligence, and quantum computing, to name but a few, each hold many times the potential for systemic harm to, or destruction of our civilizati…

Even nuclear energy is arguably a net win for humanity despite its destructive power (at least in an utilitarian way). In fact, it is debatable whether the use of the atomic bomb saved more lives than it took away. [1]

[1] http://en.wikipedia.org/wiki/Debate_over_the_atomic_bombings...

Re: Why didn't the Romans have hot air balloons?

#20

Post by dennisgorelik »

aoeuid wrote: post #3
fendrak wrote: post #2

"Such rapid and direct application of biomedical advances to humans is now inconceivable, not only in the US, but virtually anywhere in the world." This is true, but for one very simple reason: at the time of these inventions, there was no other option . If someone needed a heart operation that required stopping the heart, they would die. If someone needed dialysis after kidney failure, they died. Rapid applications…

The guy who wrote this post used to be president of Alcor ( http://alcor.org ), one of the two cryonics organizations in the US. Cryonics is in fact certainly a procedure where people will definitely die if they don't get it, particularly because it can only be done after 'legal death'. Its efficacy can't be established conclusively right now, but it's certainly more likely you'll be revived if you undergo cryopreser…

The main reason why practically nobody gets cryopreserved is that Cryonics is a form of scientific scam.

It sells people confidence that their mind can be preserved by freezing it.

http://aidevelopment.blogspot.com/2008/12/cryonics.html

That said, the author seems to be a true believer in Cryonics (however that does not make Cryonics legitimate).

The article has interesting points, but cannot really be trusted, because of multiple outrageous statements.

For example, the author states: "In hindsight, it seems clear that if humanity had decided in 1939 to colonize space, instead of ... war [WW2], we would have ... very likely self-sustaining outposts on the moon and Mars."

As of today, the humanity does not have self-sustaining outposts even in Antarctica. Self-sustaining outposts on Mars are totally unrealistic in the next 100 years. Not only because of technological impossibility, but mostly because of no need for that.

The bottom line: the author is unrealistic dreamer. His ideas might be unusual (which is good), but it's better to be very skeptical and not to trust these ideas by default.

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