Quote (card_sultan @ Jun 26 2019 06:59pm)
that was talking about your post, I guess that movie demonstrating oral care with a toothbrush triggered some memory at Space Camp.
Sure he left it open - cause he didn't want to crush your Fantasy.
U can do the same thing, watch
"Only crazy idiots believe in magical force, but whether or not you're an idiot i leave up to the reader"
Einstein explain gravity was a pseudo force as well.
https://en.wikipedia.org/wiki/AccelerationGeneral relativity
Unless the state of motion of an object is known, it is impossible to distinguish whether an observed force is due to gravity or to acceleration—gravity and inertial acceleration have identical effects. Albert Einstein called this the equivalence principle, and said that only observers who feel no force at all—including the force of gravity—are justified in concluding that they are not accelerating.
He clearly asserts that it EXISTS.
Gravity must be caused by an agent acting constantly according to certain laws; but whether this agent be material or immaterial, I have left open to the consideration of my readers.Quote (card_sultan @ Jun 26 2019 07:03pm)
the movement is caused by the squirrel, he's doing the work, not the slinky
The slinky returns to form after the squirrel lets go. Not possible if no work is performed. Slinkies perform work and are springs.
Quote (card_sultan @ Jun 26 2019 07:03pm)
From your source:
Quote
In GR, there are always two points of view--- local and global. In the local point of view, you look in a neighborhood of a point, and make a free-falling frame, and then motion is entirely in straight lines at constant velocity so that you don't see gravity. In this way of looking at it, gravity is not a "force", meaning it doesn't make a generally covariant contribution to the local curvature of the particle space-time paths.
In the global point of view, you see an incoming particle from infinity deflected by a field, and you say a force has been acting if the particle is deflected. In this point of view, every deflection is a force by definition.
The global point of view is the way in which gravity is treated in quantum field theory or string theory. The local point of view is the insight due to Einstein, and it is no surprise he would emphasize it in his public remarks.
The answer is "it depends on your philosophical definition of force, whether you take a local view or a global view." I prefer the global view, since it is more quantum, so I say gravity is a force, but I don't disagree with people who take the other view, since it is also valuable.