For Questions That Don't Merit Their Own Thread

[p1t1o]

7 minutes ago, magnemoe said:

On  the other hand the cave paintings might be an sort of weird doomsday cult, everybody else put wooden totems  out in the open for all to enjoy. 

Not doomsday cult, introvert nerds.

Doing their own fanart, in a small group or alone, away from others, shunning the light and hidden from view?

Standard nerds.

Spoiler

FYI: in my common parlance "nerd" is an honorific, not derogatory.

 

[magnemoe]

2 minutes ago, p1t1o said:

Not doomsday cult, introvert nerds.

Doing their own fanart, in a small group or alone, away from others, shunning the light and hidden from view?

Standard nerds.

  Hide contents

FYI: in my common parlance "nerd" is an honorific, not derogatory.

 

No I like my doomsday cult better; we are over hunting mammoth climate change is coming, the end of our way of life.
20K years later they was proven right. Grab tail hard, most other predictions would prove true over an timescale 3-4 times longer than human civilization. 

[kerbiloid]

Cave paintings were a manga.

Sometimes with a man-deer.

[Green Baron]

49 minutes ago, kerbiloid said:

Cave paintings were a manga.

Sometimes with a man-deer.

Can't find it in my favourite dictionary, what is a manga ?

Edited July 31, 2018 by Green Baron

[kerbiloid]

12 minutes ago, Green Baron said:

Can't find it in my favourite dictionary, what is a manga ?

Spoiler

P.S.
My Little Pony. Pilot episode.

Spoiler

Fluttershy. The Beginning.

Spoiler

and cutiemarks.

Spoiler

 

Edited July 31, 2018 by kerbiloid

[Green Baron]

For the hand negative, i agree. But the animal scenes are clearly more artistic and expressive, more realistic and less stereotypical, for the time, or not ?

:-)

Edited July 31, 2018 by Green Baron

[Diche Bach]

On 7/25/2018 at 3:34 PM, Steel said:

Photosynthesis is horribly inefficient, I think man-made solar panels are better by a factor of 10 or so.

"Efficient" in what sense?

Because if all the material and energy and maintenance that are required to create a solar panel and the amount of energy it produces is compared to the virtually "free" energy contained in a field of kelp or some other reasonable unit of photosynthesizing, I'd be impressed if the solar panel can actually compete . . . at least in the sense of the actual energy "captured" by the two methods. Harvesting the energy in the kelp field might turn the advantage over to the solar panel, but that just means we gotta figure out how to better get the energy out of autotrophs!

[Diche Bach]

On 7/25/2018 at 5:11 PM, Mad Rocket Scientist said:

Kurzgesagt made a video on one way to get energy from black holes:

 

Cool. Good stuff. Great video. Kurg is doing Galileo's work there, teaching the willing masses about science

[Diche Bach]

On 7/29/2018 at 8:03 PM, cubinator said:

Have cephalopods always been so intelligent? Squid and octopus-like creatures have been around for a long time, but have not built megastructures or colonized land or space. Is their relatively high intelligence a recent development, or have they simply never felt like taking over the world? Perhaps there was never an evolutionary necessity to advance beyond the point they are at now, and they don't have a reason to become intelligent enough to have such ideas.

What makes you think they never built any megastructures or colonized land or space?

In seriousness though . . . I know a reasonable amount about primate psychology, a smidgen about canine psychology, and a tiny bit about animal psychology in general. From my standpoint, most prevailing notions/models/theories of "intelligence" are quite stupid because, not only do they focus only on a limited range of human mental function, they focus almost exclusively on human mental function.

Bat echolocation; geese migrating; cetaceans doing all their crazy long-distance stuff out in the oceans; fungi networks communicating up and down the entire length of the Appalachians . . . obviously none of these things are quite the same as our unique human ability to grasp symbols and syntax and combine them in creative ways to exchange mental states with other human beings. But how other animals manage the wonders which they do with ease is largely obscure to us, and much of our own thinking is clouded with imperfections.

The fact that we evolved into "sentient" beings might well have never occurred anywhere else in the entire history of the universe, and might never occur again. That is how random and unlikely it looks to me based on my understanding of what is well established about human evolution and evolutionary psychology.

[cubinator]

1 hour ago, Diche Bach said:

The fact that we evolved into "sentient" beings might well have never occurred anywhere else in the entire history of the universe, and might never occur again. That is how random and unlikely it looks to me based on my understanding of what is well established about human evolution and evolutionary psychology.

Really makes you wonder if there's really some monolith sitting around for five million years or something...either way, if we are the only ones I hope we don't blow it for ourselves just yet. And I hope there are lots of creatures out there with great and wondrous abilities, even if none of them have decided that it's worth it to invent, tinker, and wonder to the point of expanding into the stars.

[ARS]

I wanna ask. If plasma is basically hot gas, does it means (in theory) plasma gun's projectile should be far more affected by wind compared to normal bullets?

[kerbiloid]

A plasma shot should move fast, otherwise it will dissipate before the wind can play role.

[Xd the great]

3 hours ago, ARS said:

I wanna ask. If plasma is basically hot gas, does it means (in theory) plasma gun's projectile should be far more affected by wind compared to normal bullets?

Imagine a flame torch.

[ARS]

7 minutes ago, Xd the great said:

Imagine a flame torch.

That would make it a flamethrower

[kerbiloid]

A cinema flamethrower, as irl it's a pump.

[Gargamel]

*mumbles something about his excellent google fu about squiggly NASA roads getting upstaged by some stupid octopi with stone hammers*

[Xd the great]

8 minutes ago, kerbiloid said:

A cinema flamethrower, as irl it's a pump.

Shall we buy one from elon?

[kerbiloid]

14 minutes ago, Xd the great said:

Shall we buy one from elon?

Once he tests them in Martian jungles ruins.

_{Jungles are on Venus.}

[K^2]

4 hours ago, ARS said:

I wanna ask. If plasma is basically hot gas, does it means (in theory) plasma gun's projectile should be far more affected by wind compared to normal bullets?

Plasma isn't going to have sufficient density to act as a ballistic weapon. If you want to build anything like a practical plasma gun, setting aside energy requirements, what you're looking for is a particle accelerator to produce a particle beam. At energies where it can qualify as a weapon, the effect would be almost identical to that of a laser beam of similar intensity. Since lasers are quite inefficient and bulky, it is conceivable that a plasma pistol might end up being more practical than equivalent laser pistol. But from perspective of user or observer, effect would be much the same.

[magnemoe]

7 minutes ago, K^2 said:

Plasma isn't going to have sufficient density to act as a ballistic weapon. If you want to build anything like a practical plasma gun, setting aside energy requirements, what you're looking for is a particle accelerator to produce a particle beam. At energies where it can qualify as a weapon, the effect would be almost identical to that of a laser beam of similar intensity. Since lasers are quite inefficient and bulky, it is conceivable that a plasma pistol might end up being more practical than equivalent laser pistol. But from perspective of user or observer, effect would be much the same.

This, an plasma weapon is an stupid idea, that is outside something like an shaped charge who is very short range (the jet is not plasma however) .
And useless in atmosphere outside at melee range as the ions will interact with air and disperse. This is also true for an particle beam. 
In short plasma weapons is an stupid idea, wonder there it cam from, ball lightning? It would also be an pretty stupid weapon if we could make it easy. 

[kerbiloid]

Depends on the beam diameter, so on the particle energy.
Say, if distance = 5000 m, beam diameter = 1 cm, then there is 1.225 * 5000 * pi * 0.01² / 4 ~= 0.5 kg of air on its way.
Heat capacity of the air is ~1000 J/(kg*K), so you need to spend (roughly) ~0.5 * 1000 * 1000 ~= 0.5 MJ to make it 1000 K and expand.
This means that it already makes sense for ~5 MJ shots. 
5*10⁶ * 2 / 1500² = 4.5 kg of equivalent projectile mass.
So, if your beam is ~1 cm thick, this makes plasma shots reasonable for anti-tank projectile shot energy.
Also you can not just through the particle beam, but first heat its way with a laser.

But this depends on minimal beam diameter which should be calculated. So, plasma shots in air may or may not make sense.

P.S.
(Added a notice: when building a Dark Citadel, add particle beam turrets to the existing anti-grunt blinding lasers and microwave emitters. Nice against dragons.)

Edited August 1, 2018 by kerbiloid

[K^2]

44 minutes ago, magnemoe said:

This is also true for an particle beam.

If that was true, radiation shielding wouldn't be an issue. Sufficiently high energy beam will penetrate air pretty well. Granted, you will see attenuation with distance, and overall range won't be great, but if you're looking for urban combat weapon, low density, high energy plasma beam might actually be quite serviceable.

Admittedly, I cannot think of any scenario where railgun isn't a better option, even if you have power to spare either way.

[magnemoe]

1 minute ago, K^2 said:

If that was true, radiation shielding wouldn't be an issue. Sufficiently high energy beam will penetrate air pretty well. Granted, you will see attenuation with distance, and overall range won't be great, but if you're looking for urban combat weapon, low density, high energy plasma beam might actually be quite serviceable.

Admittedly, I cannot think of any scenario where railgun isn't a better option, even if you have power to spare either way.

You are right, I was thinking to low energy, 

[kerbiloid]

8 minutes ago, K^2 said:

I cannot think of any scenario where railgun isn't a better option, even if you have power to spare either way.

Limited ammo.

(That's exactly why one should prefer beam weapons over mechanical ones when building a Dark Citadel.)

Edited August 1, 2018 by kerbiloid

[magnemoe]

45 minutes ago, kerbiloid said:

Limited ammo.

(That's exactly why one should prefer beam weapons over mechanical ones when building a Dark Citadel.)

In an static defense ammo is not an major issue. beam weapon has an major benefit hitting fast but pretty soft targets because very fast and often have high rate of fire. 
Anti air but also on aircraft as they have power but limited ammo storage.