For Questions That Don't Merit Their Own Thread

[Spaceception]

So I'm fairly certain there was a blog that explored an extended Apollo program, and longer space race. Does anyone have a link to that? All I'm seeing is results for the show "for all mankind", and various other sites like fandom wiki. Thanks

[kerbiloid]

Maybe it's some google:"blog  Apollo program applications" rather than "extended"?

[Spaceception]

1 hour ago, kerbiloid said:

Maybe it's some google:"blog  Apollo program applications" rather than "extended"?

Actually, that helped lead to the right search! Thanks! That search function mainly had news articles about its impact, but then I wrote "blog Apollo program alternate" (because it was alternate history), and it came up http://spaceflighthistory.blogspot.com/

I wonder why it didn't come up earlier.

[Spacescifi]

Does a humanoid need to be to stronger than normal humans to routinely climb walls with super adhesive hands and feet (suction pads on them that secrete a super adhesive sticky substance)?

I know physics shows humans normally need more suface adherence area to stick,  but if the adhesive is strong enough that is no longer necessary.

I have seen rock climbers climb either free, or with rope, so perhaps superior to human strength is not necessary to climb?

Just super adhesive hands and feet?

 

[AngrybobH]

29 minutes ago, Spacescifi said:

I have seen rock climbers climb either free, or with rope, so perhaps superior to human strength is not necessary to climb?

Having done a very small amount of climbing myself, I know strength is important but endurance is the key.

[kerbiloid]

Even a human is enough.

Spoiler

 

 

[K^2]

1 hour ago, Spacescifi said:

Does a humanoid need to be to stronger than normal humans to routinely climb walls with super adhesive hands and feet (suction pads on them that secrete a super adhesive sticky substance)?

I know physics shows humans normally need more suface adherence area to stick,  but if the adhesive is strong enough that is no longer necessary.

I have seen rock climbers climb either free, or with rope, so perhaps superior to human strength is not necessary to climb?

Just super adhesive hands and feet?

Back when I did climbing, I knew a girl who couldn't do a single pull-up, but she was still a better technical climber than me. On the other hand, if you want to go up fast, that's a different matter. Speed-climbers tend to be very muscular, because it does take a lot of strength to go vertically at speeds they do.

Since most climbers lift primarily with legs*, stairs are actually a decent point of reference. Almost anyone remotely healthy can climb a set of stairs. If you want to be able to walk a hundred floors, you need to be in good overall shape and might need a bit of endurance training. If you want to run up to the 100th floor, you need to be in top shape and do a lot of training for it.

* Some technical routes intentionally put more emphasis on arm strength, and speed climbers use their entire body. But it's not critical for climbing in general.

[Spacescifi]

1 hour ago, K^2 said:

Back when I did climbing, I knew a girl who couldn't do a single pull-up, but she was still a better technical climber than me. On the other hand, if you want to go up fast, that's a different matter. Speed-climbers tend to be very muscular, because it does take a lot of strength to go vertically at speeds they do.

Since most climbers lift primarily with legs*, stairs are actually a decent point of reference. Almost anyone remotely healthy can climb a set of stairs. If you want to be able to walk a hundred floors, you need to be in good overall shape and might need a bit of endurance training. If you want to run up to the 100th floor, you need to be in top shape and do a lot of training for it.

* Some technical routes intentionally put more emphasis on arm strength, and speed climbers use their entire body. But it's not critical for climbing in general.

 

Thank you. So I don't need superhumans (did not want that anyway).

Regarding the girl, it may have been a weight thing. She weighed less so she probably did not have to work as hard.

Same reason why little kids are at ease doing cartwheels but an adult that is not a trained acrobat may end up in the hospital with a fat bill that hurts even worse.

Muscle weighs more than fat, and guys automatically have more than females unless she is on steroids.

At first I thought to make my humanoids have a human size but weigh less so they could jump higher, run faster, and so on.

Yet I chose that for another raxe already, as I don't want all races to the same abilities 

 

[magnemoe]

1 hour ago, Spacescifi said:

 

Thank you. So I don't need superhumans (did not want that anyway).

Regarding the girl, it may have been a weight thing. She weighed less so she probably did not have to work as hard.

Same reason why little kids are at ease doing cartwheels but an adult that is not a trained acrobat may end up in the hospital with a fat bill that hurts even worse.

Muscle weighs more than fat, and guys automatically have more than females unless she is on steroids.

At first I thought to make my humanoids have a human size but weigh less so they could jump higher, run faster, and so on.

Yet I chose that for another raxe already, as I don't want all races to the same abilities 

 

super adhesive hands and feet might be the main issue here, no idea how this would work for something humanoid sized. 
Add that climbing out in the nature adhesive will often not work well as surface has dirt and stuff growing on it but you tend to have plenty of cracks and folds to hold on to. 
Monkey like feet, perhaps with cat like claws to dig in would be better, an prehensile tail would be nice

Now with technology you get smooth surfaces but you also get  technology to climb them, suction cups and magnets is not advanced tech. Main issue is lack of need.
However if you had some humanoids living like monkeys in trees they might well get an boost then you start building space infrastructure. 

[Spacescifi]

26 minutes ago, magnemoe said:

super adhesive hands and feet might be the main issue here, no idea how this would work for something humanoid sized. 
Add that climbing out in the nature adhesive will often not work well as surface has dirt and stuff growing on it but you tend to have plenty of cracks and folds to hold on to. 
Monkey like feet, perhaps with cat like claws to dig in would be better, an prehensile tail would be nice

Now with technology you get smooth surfaces but you also get  technology to climb them, suction cups and magnets is not advanced tech. Main issue is lack of need.
However if you had some humanoids living like monkeys in trees they might well get an boost then you start building space infrastructure. 

 

Good points. However I am sold on the suction plates. It's just an idea I like.

With a strong enough adhesive plus multiple tiny suction plates it could work.

Yet there is a possibilty of the suction plated being clogged with dirt, since as you mentioned, nature is dirty.

I suppose tree climbing can work, they do not get too dusty, mainly because wind and birds tend to keep the dust off.

Other option is make the homeworld more windy than Earth, with a lot of vertical rocks jutting out the surface, blown clean of dust and easy to climb.

Could do both.

Thanks for your imput.

Already have a race with cat claws though, so I cannot use that here.

 

 

[Spacescifi]

 

Are prehensile tails on humanoids more trouble than they are worth?

 

I tend to think they are. Thought about it while working the other day. I realized just how much they would get in the way of well.... everything.

 

Cups are going to get knocked over. Kids are going to swat each other in the face with their tails, plus pull each others.

Tails may look cool, but in practice they are far more suited for beasts than humanoids, since beasts use tail wagging to communicate for lack of the far superior humanoid speech.

Even if all your doing is using the toilet a tail means NOW your touching it.

Really, I think if we did have them it would be fashionable to cut them off.

Balance is surely relevant, but humanoids for the most part do not do cat-like feats nor do they need to.

 

Just my thoughts. If you wish to add for or against I will listen.

Edited May 23, 2020 by Spacescifi

[ARS]

If humanoids have tails, their culture and lifestyle is obviously already different than normal humans. Their day-to-day affair is already adapted for their physiology.

An example of this could be seen on Utawarerumono series, where your ordinary human ends up in a world full of humanoids with animal traits. When he attempted to use common sense (including pulling tails out of curiosity), it backfired on him because the culture, tradition, manners and even the clothing is different than our world

Also:

Spoiler

2 hours ago, Spacescifi said:

Even if all your doing is using the toilet a tail means NOW your touching it.

 

[Spacescifi]

2 hours ago, ARS said:

If humanoids have tails, their culture and lifestyle is obviously already different than normal humans. Their day-to-day affair is already adapted for their physiology.

An example of this could be seen on Utawarerumono series, where your ordinary human ends up in a world full of humanoids with animal traits. When he attempted to use common sense (including pulling tails out of curiosity), it backfired on him because the culture, tradition, manners and even the clothing is different than our world

Also:

  Reveal hidden contents

 

 

No doubt. Even animals are often smart enough not to pull a stranger's tail. Although I have observed a kitten pawing at his mother's tail as she swayed it back and forth, which is okay since she is family and does not mind.

Even so, I still think the whole situation would be more awkward with tails than without.

If anything, personal space is a bit bigger than before, and body suits of all kinds will have either tail cloth or tail holes.

Prehensile tails at best have limited use with humanoids who use technology. They won't be living in trees that's for sure.

From a standpoint of pure utility, tails add little to the humanoid to even begin for a normal human to want to wish they had one. Other than to play with, but far from needed and very helpful utility as far as I can tell.

It's not as if a prehensile tail has the load bearing capacity of our arms, and if it did the lower back muscles would be so pronounced that the person would at best look like a mutated for a humanoid.

Unless that's the look one is going for... my point is, all changes to reality in fiction have, or I do think should have consequences.

[ARS]

Human embryos have a tail that measures about one-sixth of the size of the embryo itself. As the embryo develops into a fetus, the tail is absorbed by the growing body. Infrequently, a child is born with a "soft tail", which contains no vertebrae, but only blood vessels, muscles, and nerves, but this is regarded as an abnormality rather than a vestigial true tail, even when such an appendage is located where the tail would be expected. Fewer than 40 cases have been reported of infants with "true tails" containing the caudal vertebrae, a result of atavism. Humans have a "tail bone" (the coccyx) attached to the pelvis; it comprises fused vertebrae, usually four, at the bottom of the vertebral column. It does not normally protrude externally - humans are an acaudal species.

Also, the term "prehensile tail" is only used exclusively for monkeys and any other tree-climber mammals that uses their tail explicitly to grasp tree branches to aid mobility. Different animals have different function of tails, some are significant for themselves (ex. Birds uses their tail like elevator for flight controls, cats for balance, fishes for locomotion), others are less important individually but benefit more for groups (ex. Deer uses their tail for signaling others). If one goes for tailed humanoid in their fiction, it's either:

1. Different species than humans, but live like humans, though their culture adapted for their physiology

2. Biological experiment gone wrong

3. Evolved from corresponding animal, with their tail merely a vestigial organ

4. Aliens (this last one tend to have tails that's strong enough to rip humans apart)

[kerbiloid]

If humans had a tail, this would increase their nonverbal communication capabilities thanks to waving.

But spacesuits would be more complicated. And the space seats.

[magnemoe]

15 hours ago, Spacescifi said:

 

No doubt. Even animals are often smart enough not to pull a stranger's tail. Although I have observed a kitten pawing at his mother's tail as she swayed it back and forth, which is okay since she is family and does not mind.

Even so, I still think the whole situation would be more awkward with tails than without.

If anything, personal space is a bit bigger than before, and body suits of all kinds will have either tail cloth or tail holes.

Prehensile tails at best have limited use with humanoids who use technology. They won't be living in trees that's for sure.

From a standpoint of pure utility, tails add little to the humanoid to even begin for a normal human to want to wish they had one. Other than to play with, but far from needed and very helpful utility as far as I can tell.

It's not as if a prehensile tail has the load bearing capacity of our arms, and if it did the lower back muscles would be so pronounced that the person would at best look like a mutated for a humanoid.

Unless that's the look one is going for... my point is, all changes to reality in fiction have, or I do think should have consequences.

An prehensile tail would be far more useful with technology than before as you has 3rd but rather limited hand to control stuff with. Easy see it used for controlling stuff like throttle on planes or an gear shift. might even control the wheel at least at speed or if you have servo. 
Without technology, it would be nice for climbing even if not strong enough to hold you. In combat putting an small mirror on the tip would be nice for looking around corners. 

You would obviously use it for communication, especially useful then you have to be silent like hunting, waving it various ways to direct the other in group. The Kzin had an system for this. 

Would not change that much I think, obviously outer types of chairs guess it would be common with an off center support for the back rest. Pants and stuff might be closed on the back over the tail. 
Don't think toilets would be much of an problem, you probably keep the reservoir up on an pipe. tails are pretty flexible. 
Now public transport and movies and other places there you sit thigh would be an issue as your tail extend back onto the next persons legs, now you could curl it forward under your own seat. 
You could close an door with your tail passing trough it. 

This assuming its an prehensile or at least pretty flexible and controllable tail like on an cat. Something too short to be practical would just be annoying. 

[magnemoe]

6 hours ago, kerbiloid said:

If humans had a tail, this would increase their nonverbal communication capabilities thanks to waving.

But spacesuits would be more complicated. And the space seats.

You have this space suit design from Freefall or rater an space dress, nice for her as she has both an tail and digtigrade legs. 
http://freefall.purrsia.com/ff3500/fc03432.htm
Its also uses an suit port. 
http://freefall.purrsia.com/ff1000/fv00985.htm
http://freefall.purrsia.com/ff1000/fv00987.htm

[Spacescifi]

8 hours ago, magnemoe said:

An prehensile tail would be far more useful with technology than before as you has 3rd but rather limited hand to control stuff with. Easy see it used for controlling stuff like throttle on planes or an gear shift. might even control the wheel at least at speed or if you have servo. 
Without technology, it would be nice for climbing even if not strong enough to hold you. In combat putting an small mirror on the tip would be nice for looking around corners. 

You would obviously use it for communication, especially useful then you have to be silent like hunting, waving it various ways to direct the other in group. The Kzin had an system for this. 

Would not change that much I think, obviously outer types of chairs guess it would be common with an off center support for the back rest. Pants and stuff might be closed on the back over the tail. 
Don't think toilets would be much of an problem, you probably keep the reservoir up on an pipe. tails are pretty flexible. 
Now public transport and movies and other places there you sit thigh would be an issue as your tail extend back onto the next persons legs, now you could curl it forward under your own seat. 
You could close an door with your tail passing trough it. 

This assuming its an prehensile or at least pretty flexible and controllable tail like on an cat. Something too short to be practical would just be annoying. 

 

Doors? If these humanoids are anywhere near accident prone as both humans and animals are, they would probably just use a mix of sliding heavy doors, and curtains where security is less a concern.

I have seen cats get their tail caught. It's not pleasant. For the cat.

But I agree, doors that sense tails and close is an easy tech fix.

Yet, given all the issues tails give, I can't help but think that cutting tails will be like circumcision male babies get.

Don't need it. In the way.

It really takes a mindset slightly different than the average guy or gal to want to keep a tail when life is easier without it.

Multiply that average person attitude by 7 billion and I do not see tailed humanoids NOT cutting off their tails since they can survive fine without them.

About the only legit reason I can think to keep the tails is if they grow back.

Since that is just painful to do to an adult, and no one likes that.

Maybe they grow back within two months? Maybe these humanoids convert their food into healing body parts more efficiently than us? With the cost meaning they go into hibernation when they lose a limb or body part. In two months it grows back just fine.

 

[ARS]

What's the highest possible altitude of hydrogen-filled zeppelin (not operational altitude, the highest altitude attainable) if we rig the zeppelin with every possible method to ascend (weight reduction, blow the ballast, remove any non essential subsystems even if it only left the zeppelin with just gas envelope filled with hydrogen and minimal control suite). Is it possible to reach the edge of atmosphere? (Assuming the thing could survive the trip through the atmospheric layers)

[magnemoe]

23 minutes ago, ARS said:

What's the highest possible altitude of hydrogen-filled zeppelin (not operational altitude, the highest altitude attainable) if we rig the zeppelin with every possible method to ascend (weight reduction, blow the ballast, remove any non essential subsystems even if it only left the zeppelin with just gas envelope filled with hydrogen and minimal control suite). Is it possible to reach the edge of atmosphere? (Assuming the thing could survive the trip through the atmospheric layers)

Much lower than balloons as an zepplin has much higher dry mass.  High attitude balloons tend to be launched only partial filled and inflates high up as air get thinner while the gas inside has constant mass.
Benefit of an airship is that you can fly it there you want but they don't fly so high they need pressure cabins. 
 

[DDE]

One thing I've noticed among Star Citizen's fictional spacecraft is the considerable occurrence of a cockpit ingress system similar that of the Tu-22: where the seat slides down out of the cockpit and through the hull.

Can anyone muster any other aircraft where this is the case? The Blinder seems like a very obscure inspiration.

[magnemoe]

1 hour ago, DDE said:

One thing I've noticed among Star Citizen's fictional spacecraft is the considerable occurrence of a cockpit ingress system similar that of the Tu-22: where the seat slides down out of the cockpit and through the hull.

Can anyone muster any other aircraft where this is the case? The Blinder seems like a very obscure inspiration.

Nice design for an plane, especially one you want to get into the air fast. For spaceships, no. Yes Gemini was pretty much an fighter setup but an spaceship mission will typically be much longer than any planes. 
Think missile torpedo boat not fighter plane, and you put the crew in the center.  No the crew quarters does not need to be protected only the bridge, most crew quarters on an battleship was outside the armored part, crew would be at combat stations during an fight anyway. same for the spaceship. You probably put the crew quarters at the bottom then landed then an airlock and a ladder. 
Now they still need some ladders to get into the plane. as seen in the image. 

[kerbiloid]

Why not if in Firefly they use a tuned Mi-24 as ambulance in the far future.

(The episode when they secretly get to the hospital.)

Edited May 26, 2020 by kerbiloid

[Wjolcz]

Can you entangle only two photons? What if we keep splitting photons into smaller, less energetic ones? Is it possible to split one photon and create three, or moee entangled photons (pretty sure the answer to this is no, but asking anyway)?

Edited May 26, 2020 by Wjolcz

[K^2]

2 hours ago, Wjolcz said:

Can you entangle only two photons? What if we keep splitting photons into smaller, less energetic ones? Is it possible to split one photon and create three, or moee entangled photons (pretty sure the answer to this is no, but asking anyway)?

Entangled states can be as complex as you want. You can have an entangled state of three photons of which exactly one is left-handed photon, and other two are right-handed, with no way of knowing which is which. In that case, measuring a right-handed photon collapses the other two into a conventional entangled pair of one left and one right, while if you measured first one to be left-handed, you immediately know that both of the others are right-handed, and it's no longer an entangled state.

In fact, this is part of what quantum computing relies on. All of the qubits of a general purpose quantum computer are in a complex entangled state with each other until you read off the answers. Even the simple QCs we're using now, like the quantum annealing computers are technically in entangled states. These states don't cover the full spectrum of entanglements possible with thousands of qubits, but they are still a subset.

Another thing you can do is "amplify" entangled states. Calling it "amplification" is a bit forced, but that's primarily to distinguish from copying, which would violate the no-cloning theorem. So if I give you a photon in some superposition of left and right polarizations, it's not possible to create a second photon in exactly the same state that is NOT entangled to the first. That would be cloning and would allow us to find out the exact state of the photon through multiple measurements of the copies. But an entangled copy is fine. You can place a second photon in the state that has exactly the same weight of left and right polarizations but is also entangled to the first. So if first is measured to be left-handed, so will the second and vice versa. This is used in all sorts of schemes in both facilitating and breaking quantum encryption. For example, it's not possible to listen in on a quantum channel without it getting detected, but it is theoretically possible to create amplified entangled "copies" of the quantum key which can be analyzed after the original message is received to produce a copy of the key which lets you intercept communication. In practice, this can get very complicated, so I don't think anyone has been able to demonstrate a physical setup that can break quantum encryption.

There's mathematical formalism for all of this. Essentially, any combination of pure states is treated as a coordinate in the state vector describing the system. Various operations and measurements are described with matrices. Operations with two photon entangled states are described with 4x4 matrices. For 3-photon entangled states you need 8x8 matrices. So things get very complicated very fast.