3 Lashes only use the Gravity Surge – Atmospheric Pressure Surge abilities are not in Ars Arcanum - WoR Updated

[Aminar]

Thirdly one could ride the winds by controlling gravity. Also airplanes fly simply by using air pressure differences (I'm an aviation major). But I still believe they rode the winds by manipulating their own gravity and flying/falling how ever they wanted.

Fourthly, the pressure surge makes sense because the bondsmiths share the surge. Their name is BONDsmith and the surge causes things to become bound.

Or both could be used. It makes a whole lot more sesnt to use gravity as the push, and air pressure for control, breathing, and most everything else. Much like how airplanes work.

It really depends what Sanderson wants done with it.

Suction is an illusion.  Similar to darkness and coldness.  Darkness is an absence of light.  Coldness is an absence of heat.  With suction, the force is applied due to a pressure gradient between a low pressure area (such as a vacuum or partial vacuum) and a higher pressure area.  With a suction cup, a low pressure area is created when a fluid is expelled from the cavity, between the suction cup and the surface the suction cup is adhered to, and the suction cup mechanically springs back to it's original shape.  However, the pressure difference between the fluid external to the suction cup and the cavity is what causes the suction cup to hold. The higher fluid pressure external to the suction cup pushes on the outer surface of the cup and prevents the cup from returning to it's natural shape.  It is an equilibrium condition.

 

With a vacuum cleaner, a fan creates a lower pressure area by pushing air from one place to another.  The "suction" is a result of the interaction of the higher pressure area outside of the tube with the low pressure area inside the vacuum cleaner.  The force is applied by the higher pressure,not the lower pressure.  Similarly, if you are in space and a hole forms in the hull of your spacecraft, you are blown into space, not sucked.  The air moving from the pressurized area to the vacuum carries loose materials with it like leaves picked up by the wind.

And Suction isn't an illusion. That's a philisophical point that has little bearing on the real world. It's a description of the effect of a pressure differential. That makes it an idea that can be worked with(Spren) and as a function of air pressure, something that someone with pressure surges could manipulate.

Gravity doesn't bind small objects together so strongly they will break before coming apart without effecting everything around them. A strong enough suction can.(That and word of Brandon.) I just find philisophical points about absence of something not being it's own concept worth refuting.

[Shardlet he/him]

And Suction isn't an illusion. That's a philisophical point that has little bearing on the real world. It's a description of the effect of a pressure differential. That makes it an idea that can be worked with(Spren) and as a function of air pressure, something that someone with pressure surges could manipulate.

Gravity doesn't bind small objects together so strongly they will break before coming apart without effecting everything around them. A strong enough suction can.(That and word of Brandon.) I just find philisophical points about absence of something not being it's own concept worth refuting.

 

Illusion is the incorrect word.  I should have said misconception.  Regardless, no, it is not philosophical.  It's physics.  Suction, is not an applied force.  The higher air pressure is the source of the force.  It is a push, not a pull.  

Edited February 1, 2014 by Shardlet

[.S.A.M.K.M]

 In soulcasting each of the ten gems stones access different material? THis means there are specific soul casters for each stuff? SO I wonder, as all surgebinding can be reproduce by fabials, what would the gem stones produce in the other orders? Also, I wonder as the knights radiants while remebered as fighters, they also did other stuff, so they would have non combative uses of their abilities as well.

[Shardlet he/him]

 In soulcasting each of the ten gems stones access different material? THis means there are specific soul casters for each stuff? SO I wonder, as all surgebinding can be reproduce by fabials, what would the gem stones produce in the other orders? Also, I wonder as the knights radiants while remebered as fighters, they also did other stuff, so they would have non combative uses of their abilities as well.

 

Brandon has said that soulcasting is a special case and that it is different than other surgebinding powers in that the specific gemstone used provides a specific and different effect relative to other gemstones.  For other types of surgebinding is does not matter whether you get your stormlight from a topaz or a heliodor.

[TomR]

Or both could be used. It makes a whole lot more sesnt to use gravity as the push, and air pressure for control, breathing, and most everything else. Much like how airplanes work.

It really depends what Sanderson wants done with it.

I think I've said this once before, but air pressure could also allow greater speeds.  Skydiving is a hobby of mine, and when you're in freefall you'll eventually hit terminal velocity at ~125mph (spread-eagled, though you can go faster if you pull in your arms and go headfirst).  By decreasing the air pressure in the direction of your fall, you'd have less drag "below" as well as an effective push from the higher air pressure "above," thus raising the limit (whatever that limit is given the atmosphere on Roshar).  Of course, we know you can multiply a Basic Lashing, which might be a more efficient way of overcoming terminal velocity depending on the stormlight required.  However, another potential advantage of air pressure-- eye protection is a big plus when you hit higher speeds solely due to the wind, which pressure might help with, though I'd also want a Reverse Lashing on in case of debris or bugs.

[Aminar]

I think I've said this once before, but air pressure could also allow greater speeds.  Skydiving is a hobby of mine, and when you're in freefall you'll eventually hit terminal velocity at ~125mph (spread-eagled, though you can go faster if you pull in your arms and go headfirst).  By decreasing the air pressure in the direction of your fall, you'd have less drag "below" as well as an effective push from the higher air pressure "above," thus raising the limit (whatever that limit is given the atmosphere on Roshar).  Of course, we know you can multiply a Basic Lashing, which might be a more efficient way of overcoming terminal velocity depending on the stormlight required.  However, another potential advantage of air pressure-- eye protection is a big plus when you hit higher speeds solely due to the wind, which pressure might help with, though I'd also want a Reverse Lashing on in case of debris or bugs.

I agree completely. I made the same point in a topic out in Standard Stromlight Archive land. It's really terrifying when you realize a windrunner could create a Vaccuum spearhead out in front of them, not have to breathe due to stormlight, and start accelerating around the sky at 3-4 G's of acceleration(90-120 feet per second per second.) without having a terminal velocity. They'd hit mach 1 in 10-15 seconds.

[Daishi5]

I agree.  The only way I can see this with Szeth is if Honorblades/Heralds only have access to one Surge each.

 

Maybe Szeth has an honorblade, but was taught by someone who only knew how to use one of the surges the Honorblade gave him access to?

[dionysus]

Air pressure cannot pull. In fact the pulling sensation we feel when having our skins exposed to a vacuum is the internal pressure of our bodies pushing on our skin from the inside. In space, for example, your blood vessels would burst in your eyes and your lungs would collapse because the internal pressure of your body is not balanced by the normal atmospheric pressure outside of your body and in your lungs.

 

A vacuum is in essence the absence of molecules in a gaseous state. Molecules in a gaseous state have kinetic energy, and the impact of those molecules against other surfaces causes pressure. A lack of molecules means there is a lack of energy and the lack of energy cannot exert a force.

 

That being said holding these surges to real world physics simply doesn't work. So just suspend disbelief.

Edited February 3, 2014 by dionysus

[Aminar]

Pull or push, manipulating air pressure can in fact move objects.  You want something to move towards you, you create a vacuum in the right place, they will move towards you.  You're arguing a semantic that doesn't change what air pressure can be used for, just how the person using it has to think.  We know it can create and seal a vacuum between two objects that is strong enough to break the objects rather than the suction,

[dionysus]

Pull or push, manipulating air pressure can in fact move objects.  You want something to move towards you, you create a vacuum in the right place, they will move towards you.  You're arguing a semantic that doesn't change what air pressure can be used for, just how the person using it has to think.  We know it can create and seal a vacuum between two objects that is strong enough to break the objects rather than the suction,

 

 

It has lots of implications. If we were to draw a free body diagram of an object held to a vertical wall by air pressure, there would have to be a force from the air pressure on the non-stuck side of the object to force it to push against the vertical wall of sufficient strength that the friction force counteracting gravity is high enough to prevent it from sliding down. This is really hard to talk about without drawings. Since gravity would still be acting on the body, the normal force required to get a high enough friction force to oppose the gravity would have to be in excess of gravity. Friction force = normal force * friction factor and friction factors are normally between .1 and .6. Since friction force is opposing gravitational force in our scenario, and the normal force is the force imparted by air pressure, and using the best case scenario of a friction factor of .6, we can substitute to find Gravitational Force = -(air pressure force) *.6. Solving that for Air pressure force we get Air Pressure Force = -(gravitational force*1.66667) Therefore the people stuck to the walls should have felt the extra compression on their bodies from being pushed on by a force higher than gravity.

 

As described in the book and WoBs ignored, the some of the windrunning surges are much easier explained by simply changing the direction of gravity. But like I said a physicist can pick apart any of these surges and its effects so we just need to suspend disbelief.

 

Also air pressure is extremely strong if we are talking about the ability to make a true vacuum. A 1 ft x 1 ft flat plate can hold up 2000 lbs for example if the other side is in a vacuum.

Edited February 3, 2014 by dionysus

[Moogle]

Friction force = normal force * friction factor and friction factors are normally between .1 and .6. Since friction force is opposing gravitational force in our scenario, and the normal force is the force imparted by air pressure, and using the best case scenario of a friction factor of .6, we can substitute to find Gravitational Force = -(air pressure force) *.6. Solving that for Air pressure force we get Air Pressure Force = -(gravitational force*1.66667) Therefore the people stuck to the walls should have felt the extra compression on their bodies from being pushed on by a force higher than gravity.

 

Not necessarily. Pressure compresses a small part of you (your clothing) against the wall, which could slightly increase μ (since more surface area should be in contact with the wall because wrinkles and other things should be reduced), unless I'm completely misremembering the physics involved. I admit it's unlikely to get above 1, though. Also, the compression should only happen on whatever is touching the surface, and the rest of your body should not actually feel the force applied (since it should be applied to your clothing), you'll just feel the force of gravity pulling you down and your clothes holding you up. Assuming a very thin slice of vacuum is created by the Pressure Surge, there's a lot of potential force on your clothing, but you won't feel it.

 

Also worth noting: gravity is 0.7x Earth's gravity on Roshar.

Edited February 3, 2014 by Moogle

[Aminar]

Beyond that 1.6 G's(R's?) in your calculation isn't enough to kill someone, and we haven't been in the head of a stuck person to know if they're having trouble breathing. 1.6 G's isn't even all that terrible. We can't be sure they aren't feeling it(assuming Szeth stuck someone shirtless to a wall at some point.

[dionysus]

Not necessarily. Pressure compresses a small part of you (your clothing) against the wall, which could slightly increase μ (since more surface area should be in contact with the wall because wrinkles and other things should be reduced), unless I'm completely misremembering the physics involved. I admit it's unlikely to get above 1, though. Also, the compression should only happen on whatever is touching the surface, and the rest of your body should not actually feel the force applied (since it should be applied to your clothing), you'll just feel the force of gravity pulling you down and your clothes holding you up. Assuming a very thin slice of vacuum is created by the Pressure Surge, there's a lot of potential force on your clothing, but you won't feel it.

 

Also worth noting: gravity is 0.7x Earth's gravity on Roshar.

 

You reminded me of something I forgot, they are held up by their clothes.

 

"When Kaladin dubiously stepped back, the Herdazian remained there, stuck to the stone by his uniform, which bunched up under his armpits."

 

This would definitely not be a gravity effect (unless the gravity only affected the clothes and was ridiculously strong.) So yea pressure it is! But pressure not applied to the person's body like I was picturing but only to the clothes in contact with the wall.

 

By the way as I said above just the force exerted by atmospheric pressure is huge. We just don't notice it because it is balanced by our internal pressure of our bodies and the pressure acts uniformly across all surfaces of our body. But if Kaladin can create vacuums, he could literally level a building in seconds. The roofs of houses are ripped off in tornadoes with very little pressure differention inside vs. outside the house. Roshar is built of stone which is only really strong in compression. Kaladin could put a vacuum on one side of a wall and the natural atmospheric pressure on the other side of the wall would destroy it instantly. If Brandon wants to go there, this would be a ridiculous overpowered ability. People think the dustbringers are going to powerful, if Kaladin can create vacuums then you could just make peoples heads explode as the blood rushes out of their noses, eyes, and ears.

[Moogle]

But if Kaladin can create vacuums, he could literally level a building in seconds. The roofs of houses are ripped off in tornadoes with very little pressure differention inside vs. outside the house. Roshar is built of stone which is only really strong in compression. Kaladin could put a vacuum on one side of a wall and the natural atmospheric pressure on the other side of the wall would destroy it instantly. If Brandon wants to go there, this would be a ridiculous overpowered ability. People think the dustbringers are going to powerful, if Kaladin can create vacuums then you could just make peoples heads explode as the blood rushes out of their noses, eyes, and ears.

 

I suspect this is exactly what the Unmade who has the Windrunner Surges (if they have Surges?) can do. Kaladin, if he can create vacuums, should also be capable of doing this, but we just don't know if he can create vacuums at all. It's possible that the Pressure Surge just makes two materials strongly attract each other (sort of like a variation on Gravity?) and there's no vacuum at all. This is the sort of thing I hope we get answers to in WoR's Ars Arcanum.

[shimwick]

In chapter 12 of WoR, Kaladin infuses the chasm wall with stormlight, then picks Lopen up and sticks him against the wall. The context clearly states that he is stuck to the wall by the back of his shirt. Now, unless we can assume that shirts have no holes of any size, microscopic or massive, no holes at the seams, etc, the shirt must, effectively, be glued to the wall. No vacuum could exist if the shirt had holes, which it must. Also, for the same reasons, it would be impossible for pressure to push it against the wall. Thus, the back of the shirt must be gravitationally stuck to the wall. It is not a pressure surge binding. Unless, of course, we are talking about an entirely different pressure surge than what it actually is, aka basically super powerful magnetism between not necessarily magnetic materials.

Edited February 19, 2014 by shimwick

[TomR]

In chapter 12 of WoR, Kaladin infuses the chasm wall with stormlight, then picks Lopen up and sticks him against the wall. The context clearly states that he is stuck to the wall by the back of his shirt. Now, unless we can assume that shirts have no holes of any size, microscopic or massive, no holes at the seams, etc, the shirt must, effectively, be glued to the wall. No vacuum could exist if the shirt had holes, which it must. Also, for the same reasons, it would be impossible for pressure to push it against the wall. Thus, the back of the shirt must be gravitationally stuck to the wall. It is not a pressure surgebinding.

 

Only if a vacuum were only applied at the edges, but the vacuum would be consistently applied across the whole surface (because the wall is painted with Stormlight).  Thus, there would be a seal operating on the same principles surrounding any hole.  Plus, WOB mentioned above.

[Swimmingly he/him]

It's magic, people. There are tiny spren holding the threads to the wall. The pressure differential is probably applied on a molecular level. Gravityspren exist, by the way, they were observed by a shin natural philosopher.

[The Count he/him]

But are the spren holding the threads?

 

Or are they attracted to whatever force is holding them?

 

Do windspren cause the wind?

Edited February 18, 2014 by The Count

[PorridgeBrick he/him]

Windspren are the wind.

[b4dave he/him]

I always thought that the lashings altered an objects view of gravity on the cognitive level. Is someone or something is stuck to a wall it was because for them, the point of gravity was changed. My basis for this was when Szeth was using his lashings in the prologue, and had to reorient himself when lashing himself to various walls and ceilings...

[Aminar]

I always thought that the lashings altered an objects view of gravity on the cognitive level. Is someone or something is stuck to a wall it was because for them, the point of gravity was changed. My basis for this was when Szeth was using his lashings in the prologue, and had to reorient himself when lashing himself to various walls and ceilings...

That's true for the first and third lashings. The second lashing, that binds two objects together is confirmed to work off of pressure by Brandon, and is functions like a vacuum seal. There's a WoR scene that proves it isn't gravity because only one object in straight line and close proximity is affected by the surge. If it were gravity it would have worked differently.

[Humph]

A lot of the discussion has the implicit assumption that the laws of nature in the Cosmere are identical in all respects to the laws of nature in our universe.  Absent a WoB on that I'm not sure we can make that assumption, although we have only our universe's laws as a basis of comparison.  For the story to be understandable there needs to be a more-or-less coherence, but not necessarily a full identification between the two sets of laws.

 

As an example, in this universe gravitational force varies inversely with the square of the distance between the masses.  This means that the gravitational force on our feet is greater than the force experienced on our head when we are standing.  It might be possible though that on Roshar gravitation force on anything that can be taken as a cognitive unity (e.g. "Kaladin") does not vary within the volume of that unit, meaning Kaladin would have the same gravitation force on his feet that he has on his head.

 

The above is meant simply to show how the nitty-gritty details of nature's laws could differ on Roshar; I am not advancing the thesis above as one to which I ascribe (although I find the notion of an object's epistemological status [cognitive realm] actually affecting its physical status [physical realm] to be an alluring one).  I would be surprised if Mr. Sanderson had worked out all the fine details of the theory in the degree the discussion has taken it.  I would not at all be surprised if he bases further details of his works on the points raised in these sorts of threads as well.

[Neru he/him]

I'd say that the second lashing is, indeed pressure based. In a strange way, but it is.

I can se the pressure being really high between Lopens shirt and the wall, so he's stuck there.

 

That being said, I still believe that those three lashings are not the only things that the Pressure surge can do, and I'm a huge supporter of the "Force Push = Pressure Surge" theory.

To my understanding, the second lashing works as follows:

 

1- Objectis infused with stormlight on its surface.

2-As soon as the object touches another surface, inbued stormlight forces, pushes the air around those surfaces away, so there is a vacuum seal between said surfaces.

3- Stormlight keeps said seal until it runs out.

 

The way it works, it would be pressure based, but still let the possibility of force push and pull.

Also, porous surfaces would need more stormlight to be lashed, since porous means more air between surfaces that would need more force to keep the seal.

 

It is possible to have high pressure diferentials to make a seal, even in open space, it would just need an external source of force to keep the air away. Stormlight seems to work very well haha.

[Aminar]

A lot of the discussion has the implicit assumption that the laws of nature in the Cosmere are identical in all respects to the laws of nature in our universe.  Absent a WoB on that I'm not sure we can make that assumption, although we have only our universe's laws as a basis of comparison.  For the story to be understandable there needs to be a more-or-less coherence, but not necessarily a full identification between the two sets of laws.

 

As an example, in this universe gravitational force varies inversely with the square of the distance between the masses.  This means that the gravitational force on our feet is greater than the force experienced on our head when we are standing.  It might be possible though that on Roshar gravitation force on anything that can be taken as a cognitive unity (e.g. "Kaladin") does not vary within the volume of that unit, meaning Kaladin would have the same gravitation force on his feet that he has on his head.

 

The above is meant simply to show how the nitty-gritty details of nature's laws could differ on Roshar; I am not advancing the thesis above as one to which I ascribe (although I find the notion of an object's epistemological status [cognitive realm] actually affecting its physical status [physical realm] to be an alluring one).  I would be surprised if Mr. Sanderson had worked out all the fine details of the theory in the degree the discussion has taken it.  I would not at all be surprised if he bases further details of his works on the points raised in these sorts of threads as well.

That WoB exists. He's said that physics functions as close to our world as he can get it, there is just the addition of Cosmere/Shardic metaphysics that can maipulate the universe on a deeper level.

[Quazar87]

I assumed that Hoid writes all the Ars Arcanums.  That's the impression I've always gotten from Sanderson, though I can't remember if he has specifically confirmed that.