Friday, February 3, 2017

Derin–Astrophysical Skiing

It turns out that Derin and I actually have something in common other than being on skis in Tignes/Val d’Isere. Derin’s favourite school subject is physics - and it was mine too. Physics is what we do when we ski and it’s what we see when we look to the skies and beyond into our unknown universe. Derin likes physics because as she says “You can join the dots and make a whole”. That’s very true and that’s why physics is enjoyable - but be very careful because there are huge traps in this process - and no airbags or transceivers provided.

Join the dots – (Hubble image)

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Real physics has to be based on empirical science and real astronomy on observation - just like real ski teaching has to be based on Newton’s laws. The problem is that the modern versions of those subjects are not based on anything real - they are based upon mathematics and hence truly disconnected from reality. If you fully understand just Newton’s three laws of motion then you will never be easily fooled. I don’t mean in terms of how to calculate and manipulate the formulas - I mean understand the sense of the laws.

Video scenes

  1. Correct uphill ski pivot
  2. Centre of Mass problem and ineffective pole support with lower ski pivot
  3. French Ski School skiing demo – hands rammed forwards – back of ski boots – pushing out heels and losing control
  4. Attempting to exaggerate pressure on the boot/ski fronts – but looking just right instead – arms natural (reflexive)

(The work on perpendicularity (turn exit dynamics) was not filmed)

 

Many years ago I said to Derin that we don’t know what “time” is (now her favourite aspect of physics) and I explained that when it comes down to it we don’t know anything about either where or “when” we are in this universe - we have no clue where we are - we are utterly lost. The universe is probably infinite so that makes time infinite. What’s very clear is that black holes, Big Bangs, curved spacetime and “balancing skiers” are all mathematics - for which there is zero genuinely tenable observational data and zero agreement with the laws of physics - despite the common false assumption that there is - asserted by mathematicians who like religious priests use circular logic (referring only to their mathematics) to justify their cherished beliefs and fund raising. This leads humanity straight down the rabbit hole to collective insanity - one huge waste of resources and opportunity.

Ski teaching fell unwittingly into this wasteful bottomless pit - through the use of the term “dynamic balance” - which is mathematics and not reality https://en.wikipedia.org/wiki/Fictitious_force However, although “time” is some strange expression of infinity - we don’t have the luxury of infinite time here - so let’s move on and deal with the infinite mystery of the world some other time by confining ourselves just to the infinite mystery of skiing...

 

Derin’s Assessment

One Ski: To assess Derin’s current skiing level she was simply asked to ski about 150 metres on one ski. Didn’t happen! Haluk did his best, straight-lining it like a demented snowboarder on one leg. At least Haluk could stay comfortably on one leg even if unable to turn.

Short Turns: We then looked at short turns on steeper terrain. There was a lot of pressure on the backs of the ski boots, turns not being completed and eventual loss of control. The hands were held forwards but nothing else - in fact everything else was firmly pushed backwards to compensate for ramming the hands forwards- I wonder where that comes from? (Look back a few posts!) There was no pressure on the outside ski at the start of the turns and it looked like the skis were being pushed outwards. (later confirmed when working on pivoting)

Carving: Carving was ok but the dynamics very limited. The term “Dynamics” here is a Newtonian term - in other words “reality”!

Mindfulness: Those three “whole” aspects of skiing just gave me an overview of where we stood. Basically it means that not only were the dots not being joined up but there weren’t so many dots there to start with. Skiing being “holistic” is very permissive in this way and it allows itself to be called skiing even when lots of dots are missing or not joined up. (unlike a car - which not being holistic will go nowhere if bits are removed). Delving into this more directly I asked Derin what she was thinking about regarding her body when skiing. Apart from “pushing the foot forwards” there was a blank, effectively giving us just one “dot”, albeit a “whole” dot. Although the holistic quality of skiing is a blessing in that it allows up to develop progressively without doing anything perfectly - it is also a curse in that is lets you ski like a zombie and most people are content with that. I guess zombie skiers don’t know they are zombies - like a goldfish doesn’t know it’s a goldfish, just going round and round in its bowl until its final trip down the toilet. There is a “zombie antidote” however and it’s called “mindfulness”.

 

Derin’s Quest

Asked what she really wants to do with her skiing Derin revealed that she wants to ski better in difficult snow. That’s a reasonable goal.

Knowing that the human mind works (as does skiing) using “self-organising principles” (proven by Nobel Chemist Ilya Prigogine - whose main passion is “time” - but who unfortunately defines it with statistical mathematics) I slotted this objective in the back of my mind and then set about looking at the dots. Following my own intuition and experience the idea is that the dots would self-organise into a result for Derin in the few hours lying ahead of us. This is specifically why I never plan any lessons. The famous writer on thinking - Edward De Bono - named this exact process of self organisation in the mind “Lateral Thinking”.

My process is lateral thinking but the goal is to get Derin’s skiing to self-organise too. This is the science of “Emergence”.

 

Derin’s Dots

Pivoting

Derin had once before - in another time, perhaps another life - learned how to pivot. This ancient skill was clearly lost. Yes, the body she had even a minute ago was gone forever just as that minute was gone forever - but the skill was not supposed to disappear along with it. Perhaps I should have told Derin that before. One time a few years ago when discussing this issue of “time” with Derin she looked behind her to see if she could see her old self.

We began with the uphill ski pivot. All the details and versions of pivoting are on the fixed page here for reference: http://skiinstruction.blogspot.co.uk/p/pivot.html

Derin ended up stuck - unable to pivot because she was trying to force the tail of her ski outwards and was doing this by attempting to twist her body (pelvis and feet included) into a turn downhill. Many, many, many missing dots here!

The ski is sitting on its uphill edge so pushing the tail uphill is just not going to happen. The foot should be rolling and not twisting at all. The pelvis and upper body should not rotate and attempt to torque the ski into any turn. The foot should be on its lower edge and the ski on its upper edge - the edges of each separated and clearly defined and sensed. The pole should be firmly planted downhill to support the body weight and the then the turn initiated by moving weight (centre of mass) onto the pole, pulling the front of the ski into a sideslip into the turn. The ski edge changes halfway through the turn when pointing downhill.

 

Centre of Mass

There are no dynamics during pivoting - the pole providing all the support for controlling the Centre of Mass – and the CoM is as always the reason for the skis turning and hence the skier being turned. The pole is only used for support when pivoting and not when skiing forwards using dynamics. The pole is for use to help the centre of mass into a turn (and sometimes through the development of the turn) and in this case it replaces dynamics as the support for the Centre of Mass in this relatively static situation. In contrast the pole should not be “planted” when skiing with dynamics and in any case it is never planted to complete a turn (as is often claimed in ski school dogma). When moving forwards and using the Magic Wall the skis generate an uplifting force which replaces the need for pole support completely - so then the pole is only used for timing and feedback (proprioception) as the body falls into the next turn – in which case a “pole touch” may be used to replace the pole plant.

Derin succeeded in recovering her skill for the uphill ski pivot but did not manage to get a handle on the downhill ski pivot - because this is where control of the Centre of Mass using the ski pole is hyper critical. Without being able to do both and then join the two pivots together it’s impossible to ski well and turn in control on one ski.

In the two photos the body should have moved over the pole more so that (in the photo on the right) the body stays over the left ski.

 

 

 

 

 

 

 

 

 

Inside Edge of the Foot

Both types of pivot require the foot to be held on its inside edge - this being a far more critical aspect than most would realise. We tend to respond to pressure on the outside of the foot through reflex by pressing on it so it takes a deliberate effort to avoid stepping onto it. The geometry of the body is such that regardless of which edge of the ski you need to be on it is only the inside edge of the foot that works - and this is the real key to edge control in pivoting (and beyond). The inside edges of the feet also engage the adductor muscles in the legs which engage the core muscles in the pelvis and lower abdominal area and all of the system of postural reflexes and involuntary muscle activation.

Basically what I’m saying is that skiing on one leg is not a trick - it’s a real litmus test for skiing ability. Remember that in addition to dynamics skiing is about skating - and skating is one leg at a time - as with skiing.

 

Perpendicularity

We didn’t have the time to look deeply into Derin’s body mechanics - nor did we have the Hubble telescope available for looking deeply into space to expose the errors of the Big Bang theory (Lambda Cold Dark Matter model) - so those dots are left aside for the moment - whatever a “moment” is. Let’s face it - we don’t even know what gravity is - because it is not geometry no matter what Saint Einstein's mathematician Riemann might have us think. The ancient Chinese had a great way of looking at the mystery and called it “chi”. They said that the power of the universe flowed through the body - well gravity does a pretty good job of that. They also related it to “centre” of the body - which pretty closely agrees with the Centre of Mass. Sensibly, they never said what it was and we still don’t know. However in the West we never had a word for “chi” because the word ‘Energy” (from Greek) only entered our vocabulary during the Industrial Revolution as a way to help develop the physics of thermodynamics for steam power. In the West “energy” is just a mathematical number - a constant measureable quantity - whose quality shifts from one thing to another - heat, kinetic, potential, chemical, electrical, nuclear etc but without ever being pinned down and without the quantity changing. This act of measurement gave us the industrial revolution - but also the illusion that we actually understand what we are dealing with - when in reality we know no more than the ancient Chinese and yet have built impenetrable mathematical educational walls now that prevent further understanding from being accessible to anyone. Those walls are more concrete and bigger than the Great Wall of China.

When you stand across a slope you are perpendicular and vertical at the same time to the skis which are horizontal. Vertical and Horizontal are referenced to gravity - not the slope.

When the skis turn downhill your skis will incline at the same gradient as the slope but now you have to think about keeping the body perpendicular to the skis. Failure to adjust to slope perpendicularity will result in the body automatically trying to remain vertical by using acceleration sensors in the brain - a bit like the ones in my Android telephone. Fortunately my Android telephone is relatively stupid and so it does not try to remain vertical unaided. The point is that people are generally used to being vertical in the daily battle with gravity but in skiing we use gravity to slide and so remaining vertical permanently is inappropriate. Once again being a slave to reflexes just gets us into trouble. Our goal is to achieve perpendicularity to the slope. The issue with the outside edge of the foot is caused by reflexes directly between the foot and spine but verticality is in the head and brain - so it needs a fair bit of re-training. Fortunately we were born to ski (at least I choose to believe that I was) and this reflex seems to adapt quite naturally - so that the skier stands comfortably upright, fully relaxed and at ease - when accelerating downhill and properly perpendicular to the slope. The “normal” force is the name given to the force of your weight perpendicular to the slope and this is just like having a slightly reduced force of gravity on the body - the rest of gravity being used to accelerate you - and being something you don’t actually feel (you only feel the elastic resistance of the ground). So you feel a reduced elastic resistance of the ground and all this apparent “leaning back” in the ski boots and being stuck in vertical is just a weird reflex driven anomaly - like a mule being stubborn and refusing to move. It’s a bit like trying to see somebody else's perspective in an argument - seemingly impossible at times.

Photo on the left is “back seat ESF – ministry of silly arms and pole use” – and on the right (forwards) looking cool.

SnapShot(16)

SnapShot(17)

 

 

 

 

 

 

 

 

 

To change Derin’s perspective here, rapidly, a radical approach was required. Due to not having a big rotational problem of any kind (other than when attempting to pivot) it was safe to encourage Derin to lean very heavily forwards on the fronts of her boots hanging over the fronts of her skis. We started out with this in a snowplough to feel the fronts of the skis and then took it into parallel - despite the Hee-Hawing donkey sounds of Derin complaining behind me that she felt it was dangerous. Persistence gradually got her to feel the fronts of the skis and of course this obliged perpendicularity in the fall line. The other advantage is that Derin can now use the fronts of her ski boots and skis and so get more value out of her equipment because up until now she was only using the rear half.

When skiing and when loads build up in the second half of the turn security is maintained by the outside hip being pulled back, strong angulation and inclination being combined and sinking down deeply into the turn - regardless of being on the front of the ski or not. One reason for the extreme donkey effect is that none of this is properly in place and so the skier is at risk to completing the turn with a somersault. I showed how the front of the ski becomes a lever against the resultant forces when everything is positioned correctly.

 

Turn Exit/Entry Dynamics and Perpendicularity

Getting onto the front of the skis - getting perpendicular  - is slightly more complex than “leaning” forward to extremes. In fact we don’t want to lean forwards - that’s only an exercise to develop new feelings, perspectives and drive out the donkey effect.

We use the end of one turn to set up perpendicularity for the next turn. The loaded downhill ski lifts the skier up and out of the turn (aided or not by support  and/or muscular impulse from that leg) so by coming right out and into “neutral” - skis flat - the entire body is alread perpendicular to the slope and in place for the skis coming around - and in fact is slightly ahead putting the skier on the fronts. This automatically induced perpendicularity is the biggest key to skiing in difficult snow - which was the stated goal of Derin at the start of the session. Looks like things self-organised for us after all then.

We practiced “hanger” turns - where you hang your new outside ski in the air as long as you comfortably can through the turn transition to ensure the body coming over the lower ski into perpendicularity - taking this off piste and into difficult snow.

 

Mindful Skiing

Towards the end of the session Derin was asked to think about all the things we had just worked on and how they involved awareness of the body. Learning to focus internally on the body parts, proprioception (relative positioning of body parts) and overall movement of the body is of serious importance. Taking this one step further all motion should begin from the centre of the body - internal movements and overall movement. Focusing in this way also centres the mind - removes anxiety and increases awareness. This is what I always try to do and why skiing never bores me - even skiing with a complete beginner - because there is always something to learn even in the smallest movement. The person who does not focus internally - but thinks instead about her friends, where she is, what time it is etc. will get end up being a bored person - bored with everything and dissatisfied not just with skiing but with life. When I next ask Derin what she thinks about regarding her body when skiing I hope to her a very different answer.

 

Conclusion

  1. Skiing

  1. Dynamics

  2. Skating

  1. Inside Edge of the Feet

  2. Centre of Mass

  3. Perpendicularity

  1. Edges of skis

  2. Pole Use

  3. Fore/Aft

  4. Turn entry dynamics

  5. Turn exit dynamics

Looking at each one of the above you can see that going into finer detail reveals greater numbers of “dots” which all join up. This tendency would probably follow a Fibonacci Number list (1, 2, 3, 5, 8, 13… ) corresponding the Golden Mean (spiral) - yielding more and more dots in a fractal (1.618… ) dimension. Those dots are self-organised into stability through a dynamic equilibrium. Shall we lose ourselves in mathematics here? Definitely not! Skiing is real - math is not - it only represents measurements and relationships at best.

Astrophysical skiing aside the main issues common throughout are the three highlighted in blue.

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