Yes, I know about this intriguing point of view. Still, I believe that, in a sense, it opens more questions than it answers. For example, if time "doesnt exists" (in the common sense aproach), the future is already "there".
But, it is not. The experience of time might be subjective, but still the changes are from existence to not existence, from being to not being. Sorry I cant put it in a better way. Past is determined fixed, like points in certain (measurable) space, but future is open.
You put it fine. You have actually touched on one of the unsolved parts of physics. The descriptions that quantum mechanics and relativity give us of spacetime do not include this notion of an "open" future, but because of the inherent probabilistic nature of quantum mechanical descriptions of particle interactions, we can't precisely predict what's going to happen until it already has. In fact, when something happens, there are only certain parts of it we can know, or can ever have known later. This is because of the uncertainty principle.
At the point in spacetime where a particle interaction occurs, according to the idea of decoherence, a measurement occurs of the interacting particles; until that happens, their parameters are only probabilistic calculations of what their values would be if they were measured right then. But at the point where the interaction actually occurs, some of the values get measured, and others become unmeasurable.
Now the laws of physics according to both relativity and quantum mechanics are time-reversal symmetric; that is, if you see an interaction happen in a certain manner, you can be sure that it would be a valid interaction if it happened in reverse. Actually, it's deeper than that; you also have to reverse the charges, and something else called the parity, a spatial symmetry of the individual particles, for complete reversal symmetry. But since relativity doesn't directly deal with either charge or parity, it is truly time-reversal symmetric.
So the fact that individual interactions, and this in turn through something called the Fluctuation Theorem leads to the laws of thermodynamics, specifically the Second Law of Thermodynamics, which as you no doubt know is not time-reversal symmetric as we experience things, are time-reversal symmetric indicates that something very odd is going on. The really interesting part is that it turns out that the 2LOT really
is time-reversal symmetric, but only if the entropy is so high that it's almost constant; in a low-entropy system, like our universe, it becomes asymmetric.
There are no clear answers from physics in this area. What we know is that the universe started in an extraordinarily low state of entropy, and has been increasing ever since. Still, on an absolute scale, even though it's been 13.5 billion years since the universe began, the entropy is still quite low. It will take a very, very long time- trillions of years, that is, thousands of billions- scores or hundreds of times as long as it has existed now- for the entropy of the universe to become high, though it is increasing all the time very slowly. Until that happens, the entropy of the universe will remain very low, and we will see time-reversal asymmetry in the 2LOT. Most physicists believe that the extraordinarily low entropy of the early universe is responsible for the time asymmetry that we see, but they can't prove it, and they won't really be happy until they can, or they find out something else that accounts for the asymmetry we see around us.
Regarding this I still believe such "effects" are irrelevant, in the sense that we might be well just to experience the acceleration because its the only causal force involved. Im thinking that we cant experience gravity because falling its the same as no movement, or acceleration, at all. In this sense, gravity is as relative as movement. Its not a cause, but an effect, so to speak.
Hmmm. Well, there are two points of view, as I pointed out to 69dodge. Our ordinary point of view is that we are "sitting still" poised on the surface of the Earth in a gravity field. We observe that inertial objects move relative to us, and that motionless objects (we ourselves, for example) experience acceleration.
We think this is a natural state of affairs, since it is all we have ever experienced; but in fact, the natural state of affairs is just what Newton said: a body in motion remains in motion, at a constant velocity, unless acted upon by a force. We, on the other hand, observe that bodies in motion fall to the ground and stop. This is not a natural state of affairs in the universe at large, however; we only see things this way because we live in a gravity field, and think in those terms. You must cast aside this, for want of a better word,
prejudice, that the situation you see around you is the natural one, and understand that everything you see and everything you experience is influenced by this gravity field.
From this, Einstein understood that the inertial frame of reference is the natural state of motion, and all motion must be measured relative to the inertial frame. From this point of view, we are not motionless; we are accelerating upward forever. What an inertial object will see is that we will accelerate upward toward and past it (assuming it can fall through the Earth). This is the true state of affairs, and thus we can see that
gravity is acceleration. To understand relativity, you must accept this as a proven fact.
