Q&A: Particle and Wave
Particle and Wave
Question
With God’s help,
Hello Rabbi Dr.,
I wanted to ask: there is a question about how a force acts at a distance on two bodies, for example gravity or electric force.
So there is some analogy I saw that people like to use, that a heavy body or one with potential supposedly bends the space around it and then the other bodies move toward it, but I didn’t really understand what that solves. After all, the assumption that for a body to move toward the heavy body through space also requires a force itself (otherwise it would remain “floating” in space).
Also, I saw that there are various claims that there are tiny particles that carry forces from one body to another, but then the question arises: what caused them? And then apparently you would need an additional particle to carry them. And so if we continue the regression to infinity, we get something that is a continuum of particles in space, so that our body is actually a kind of wave.
True, I don’t think these implications really explain too many findings in physics such as quantum theory and the like. But still, what does the Rabbi think?
Answer
These are questions for which one really needs to study physics. It is hard to explain them briefly.
The assumption is that there are particles that carry the force from one body to another. The gravitational force is carried by gravitons, and the electromagnetic force by photons. I do not see why there is an infinite regress here. What does “what caused them” mean?
As for the bending of space, that is general relativity. According to this theory, one can replace a force acting between particles with a curvature of spacetime around one of them. For a better understanding, one needs to study relativity.
Discussion on Answer
I once heard an objection on this topic that was left unresolved, and I would be very glad for an answer.
The only force that can be understood without action at a distance is pushing. But even that pushing is hard to understand. Before the thing doing the pushing enters the domain of the thing being pushed, the thing being pushed will not budge from its place. And before the thing being pushed moves from its place, the pusher cannot enter there. And if they arrive simultaneously, how do those two know that the time has come to move together? The transfer of momentum itself requires study if it is not a simple push. (I don’t know if it’s relevant, but I read the analytical article on the paradox of the arrow in flight, and I don’t know how to extract from there a solution to this question. So if using the solution from there is relevant, a short explanation would help without the trouble of repeating it all.)
Greek philosophers already raised this objection about causality. It is commonly accepted that the cause precedes the effect, but that is not so. Cause and effect always come together simultaneously. And there is proof of this, for if there were a difference in time, then there would be a moment in which the cause exists and the effect has not yet occurred. In short, cause and effect always come together and there is no time gap between them. The interesting question is how, if so, a duration of time is created such that the whole process (the causal chain with its several links) takes time. That is already connected to the concept of continuity.
Oh, I missed that, thanks. I need to think about it.
[Note to myself that ought to be in small print because it is only a raw, unprocessed thought: everything is very vague to me right now, but it seems to me that the question about pushing in time (causality) is a bit easier than the question about pushing in space. Because time passes on its own.
In causality it is possible that they come one after the other, like the grease on the stroke of midnight in Egypt. Time is continuous; there is a “moment” in which the cause exists and the effect has not yet occurred, but there is no duration of time like that. And that also explains how a duration of time is created that the whole process takes. And only the usual question remains: what causality is at all beyond temporal succession. But in pushing through space it seems impossible, because after all nothing needs to move, and spatial transition, unlike temporal transition, does not happen on its own.]
In space there is no problem, because indeed the entry of one ball into the area of the other happens simultaneously with the other’s departure. דווקא here I do not see a problem. I do not see any connection to the fact that time flows on its own (by the way, that is not clear at all, but we won’t step on that landmine here. I discussed it at length in the fourth book of Talmudic Logic).
The entry is simultaneous with the departure because it is not the cause of the departure, but rather “force,” and therefore forces cannot be grounded in pushes, as the question was meant to show.
I’m already plotting to get the fifth book ever since a previous answer; is there any point in reading the books in order? I’ve only read from the series the first two books when they came out (truthfully, a disgrace. The taste of the first is still with me to this day).
As I said, I do not see a problem with this.
There is no importance to the order.
Regarding gravity, it is more correct to think that no force acts on a body that is in free fall. In order for it not to fall, a force must be applied. Left free, the body simply slides downward toward the heavy body. Without force.
As for the infinite regress, it seems you are aiming at Zeno’s paradoxes—how motion is possible at all.
But there is no regress; there are laws of nature that are just given. And “what caused them?” The laws of nature.