Yes. Say it reaches the apex at time t2. Then there is a path compatible with the 2nd law in which it remains there for the period [t2,t2+h) for any h>0. So that path must be what happens rather than a path in which it continues down the other side. — andrewk
My law prohibits the ball rolling down (a solution not in U) because there exists a solution in U, ie in which it does not roll down, and the law requires that a solution in U be taken in preference to a solution outside it. — andrewk
What do you think about this? — prothero
I'm not sure I understand the question. The above law would mandate that a ball sitting stationary exactly on top of the dome would not roll down. The second law does not mandate that. — andrewk
This states that the solution must have locally constant velocity both looking backwards and forwards if that is compatible with laws 2&3, else locally constant future velocity if compatible with 2&3, else locally constant past velocity if compatible with laws 2&3. Otherwise the law is silent. — andrewk
An expansion that prevents bifurcation could be:
'Where there is more than one future movement pattern of an object that is compatible with the 2nd and 3rd laws and the conditions in place at time t, and one or more of those patterns involves the object's velocity remaining constant for the period [t,t+h) for some h>0, the pattern that occurs will be one of those latter patterns'.
Very wordy, I know, but it has to be in order to deal with nonphysical cases like this without just disappearing into Law 2. Note also that it leaves open the possibility that there may still be bifurcations possible with this law - not the one discussed in the paper, which would be ruled out, but other ones in even more pathological cases. I suspect it may be possible to prove there cannot be, but that's just a hunch. — andrewk
I got a bit lost here. Newton's third law is that for every action there is an equal and opposite reaction. I can't see how that law is relevant to the questions being examined in this scenario. Can you outline what you had in mind here? — andrewk
As I stated above, the luck objection seems to me different from what I meant and I personally don't find the actual answer all that interesting. — Benkei
Most everyone when they think luck and change are relevant. It stems from an inability for most to properly understand QM theories, which, admittedly, I only understand at a limited conceptual level but enough to spot the mistake. Too many think QM theory is an example of ontological indeterminism. It isn't. — Benkei
This paper — Benkei
To base free will on the mere fact that not all processes are predictable is even a worse case of not understanding what we're talking about in my view. — Benkei
My first red flag with Robert Kane is therefore his equivocation of indeterminism and chance. That means he appears to be firmly in the territory of epistemological indeterminism which simply isn't interesting for the reason above. I'll read his full paper later but that's just a first few remarks to clarify my position based on his first two pages. — Benkei
My argument is distinct from the luck argument I guess or Robert Kane misrepresents it in his paper. — Benkei
Newton's first law says that an item will remain in its state of motion (which is interpreted to mean its velocity does not change) unless acted upon by a (net) external force. So the ball in a perfect, stationary position at the top will remain in its state of motion, which is stationary. It will not roll down. Hence the solution is non-Newtonian and must be rejected. It satisfies the second but not the first law. — andrewk
I suppose if we send it sliding up with exactly the correct initial velocity, and no touching it after we release it, all higher derivatives of displacement will be zero once it is on its way up. It follows that it will stop at the top rather than continuing down the other side, because it will have zero velocity and zero horizontal force on it at that time. — andrewk
The higher derivatives would have to be nonzero for the ball to pass the cime and go down the other side. If it stops there, there are no discontinuities because Jounce and Jerk were already zero on the way up.
Comments suggest to me that the cause of the sudden spontaneous motion is a concealed fourth derivative jounce. So it is like the ball is set down on the apex in the middle of just being about to snap. — apokrisis
So I don't think this case does what it at first seems to do, which is to generate breaking symmetry out of nothing. The breaking symmetry is always there in the discontinuous Jounce, which we have simply assumed. The plausible physical solution is that which has smooth displacement and all derivatives are always zero - ie symmetry doesn't break. — andrewk
OK. I don't find assigning causality a productive exercise, so I'll leave the field to those that do. — andrewk
So long as people can't wrap their head around the idea that saying "indeterminism is necessary for free will to exist", really means that everything they decide is totally random as a result, we'll continue to have these discussions. — Benkei
Making the generic cause to be about the impossibility of placing a ball with arbitrary accuracy on an apex is both another way of saying the same thing, but not quite as strong a version as focusing on the impossibility of eliminating triggering fluctuations. — apokrisis
That is my view. The ball fell because when it was released by whatever was holding it on the apex, its centre of mass was not exactly above the point of contact with the dome, so it started falling. — andrewk
Do you buy his story? — apokrisis
I'm not sure I understand your point. If the particle is perfectly balanced on top of the dome, then there it shall remain until some net force moves it. — LD Saunders
All I can come up with is limited free will. We can't choose what we want but we can choose how we satisfy our wants. — TheMadFool
But now if you time reverse the story, you still only can arrive infinitesimally close to the apex, not actually perched exactly on it. — apokrisis
How so? If the ball has mass, it has inertia. A push is required to set it moving. — apokrisis
If the net force acting on the ball bearing was zero, why would the ball move? On the other hand, can a ball sit on another ball without moving? Or must it eventually move as a chance event? — Bitter Crank
Latest news... — Proto
I don't know what all they will investigate, but from the POV of the administration, the less of a fishing expedition the better. — Bitter Crank
From reports I've been reading, the FBI investigation will be extremely half-assed. — Maw
wouldn't Mark Judge who was watching, take the key in his pocket? Would he leave the key there, so that she could somehow escape? — Agustino
I don’t know if it’s something that every conservative would rule for. — Michael
There’s also an upcoming court case that is concerned with double jeopardy and federal pardons (i.e can you subsequently be charged for the equivalent state crime). — Michael
It seems tactically and politically stupid from where I'm standing but perhaps I'm missing an angle I'm not considering here. — Benkei
I do think it's odd that Kavanaugh is so hostile to the idea of an FBI probe into these supposedly false accusations. — Erik
:gasp: Woah. — StreetlightX
The partisanship seems to be owned wholly by the republicans by refusing to call Mark Judge to testify or to have the FBI look into Brett's moral character in more depth. — Benkei