It's something of a semantic difference whether worlds should be said
to fuse in the MWI....One way of describing it is to say that there are two worlds, one where the photon passes through one slit and one where it passes through the
other. Then the worlds fuse when the photons hit the screen and this is the cause of the interference.
George Levy wrote:
From the the point of view of each conscious entity, the world appears rational, but in fact the observed world is an infinitesimally thin section of the chaotic MW.
Chris Maloney wrote:
It has always seemed kind of circular to me: that particle wave functions are superpositions of worlds, and worlds are collections of particles. But perhaps it's circularity is somehow fundamental.
Fusing is a fundamental process of nature and probably will eventually explain why there is a QM probability density. Better not to consider fusing worlds with the slit screen experiment. Instead consider defined particle waves up to matter, moving toward comparing probable worlds versus improbable worlds.
An electron has a far more defined wave, highly defined in almost all situations. A cue ball bouncing around a table comparatively has almost no wave. Its future worlds split as we split, and yet, (the density) of what is possible is narrowly defined. The reason our future is so narrowly defined, compared to all the chaotic possibilities, is fusing. For example, the reason the path of the cue ball makes no radical departure from physical laws, why it doesn't suddenly zips across the room in one of all possible directions, (like a photon) is because our present is constantly being narrowed. That is a given. Why, the reason is that even though there are many possible paths in the immediate future there is only one inevitable distant future or final outcome of a path of time. Thus there is convergence.
The idea of convergence is that all paths of time move inevitably toward the same future. It is based on the fact that there is a point of balance within the set of all possible states, like zero on the mathematical plane. That most balanced, or most neutral, point within all possible states (worlds) acts like an attractor. It pulls time toward it. It is literally made inevitable because of the simple fact it is an ultimate point of balance. Being inevitable, it pulls time always toward it, which means that it dictates what is possible for every path of time. Not just ours, but all worlds, as all worlds begin with a Big Bang. In other words, our present is shaped by the future.
Imagine that you are suddenly informed that you must be in Paris tomorrow at noon. Naturally, that future requires that you pack, tell others you are leaving, buy an airline ticket, make arrangements for someone to feed the cat. Suddenly that requirement dictates every minute of your life. Now imagine hypothetically that there are many possible immediate paths for you but only one possible future state. At twelve noon you will be in Paris. The only future that exists for you is you will be in Paris in one precise location. Now consider how that single future dictates your past. You can take numerous different airlines, different planes, eat different meals, talk to different people. However, if that future is inevitable it will eliminate a myriad of possible paths that branch outward seemingly in all directions away from Paris. For example, all the paths where you miss your plane, get hit by a bus, are made impossible. That inevitability for you to be in Paris becomes for you a set of physical laws. It defines your QM waves. No possible paths lie outside the myriad of paths that carry you to your future destination in Paris.
This is not just an idea. I have studied the idea of a cosmological convergence for years, backwards and sideways. I may not be able to explain it so that you can understand it, however, it doesn't require a lot of study to recognize that if there is an inevitable future, one single possible ending of time at a single balance point in the overall set of all possibilities (state space), then that state would influence the past of every path of time. It would shape the world in a way to bring about itself. It would determine the laws of physics, determine the probabilities that make one world path possible and another impossible.
What I have been trying to explain in prior posts is that before there are physical laws, before there are many worlds or many paths of time, even more elementary and excluding a chaotic infinitude, there is a fundamental shape to nature, to what is possible of physical existence. Regardless of differing physical or mathematical descriptions of a state of infinite density, there is no meaning to the idea of a state of greater density than infinite. The very basic concept of infinite density, regardless of it being a single state or many states (of different mass), is a boundary to what is possible in physical existence.
Furthermore, the universe can only expand to an ultimate extreme. A circle can expand infinitely, becoming ever larger, with the curvature of any distance along the circumference decreasing, moving ever nearer toward a straight line. Yes, there is an infinite number of possible measures of curvature, yet there is a single state, pattern, condition, whatever, where the curvature of the line becomes zero, the point at which a line through space is perfectly straight. Further, there is a single state at which all lines are perfectly straight, what I refer to as Flat Space or the state of Omega Zero. Perfectly straight lines and the extreme of flat space correlate directly to a common physical condition or the point in physics of absolute zero mass, density, curvature, temperature, time, and volume. Flat space extends infinitely in all directions. Flat space is a boundary.
Infinite density and flat space are ultimate boundaries to a set of all possible states. They are in essence the boundaries of a spectrum of all possible states, a set that is infinite yet bordered by those extremes. Such a spectrum is the most elementary model that can describe nature. It is also polar, like the mathematical plane, with a positive and a negative side, making absolute zero or flat space the balance of all possible states, and our inevitable future.
The universe is expanding not ever nearer to flatness, but rather directly toward flatness. An inevitable future is why we live in such a defined and consistent universe. However, all this has led me to realize that the world we know isn't a single path of time, but rather space-time is literally shaped by multiple and opposed directions of time. As well as moving forward toward zero, within the very space that surrounds us, time tries or does partially move backward toward past-like states, toward density. The reason the universe expands, and why positive and negative particles relate in they way they do, polarized, is because of the inevitable flatness of the future and its requirements of the present, but as well there are of course less probable directions of time away from zero, mainly those that lead backward toward the past or toward infinite density, or gravitation. The world we know isnít one path of time but rather it is literally shaped by multiple and opposing directions in time.
Again, convergence toward flatness is what narrows what is possible for us at every instant. It produces the consistency of the world and defines the density of every probability wave, quantum and gravitational. There are strict requirements upon our universe made by the future. And thus I believe we do not live in an arbitrary universe, one of all chaotic and ordered universes, defined only by the anthropic principle. There are physical laws because of what is physically possible. And what is possible in time is very defined and all temporal worlds are ordered and rational.