I think it's much more likely that there's something basic that we don't understand, than parallel universes. — Wayfarer
The basic thing that we don't understand is the nature of time. There is One fundamental principle which is well proven by experience, and therefore produces the most sound base for any ontology, which is ignored, neglected, or even dismissed by most physicists. This is the basic assumption that there is a substantial difference between future and past. We know that this is true, because things in the past have already occurred, and things in the future have not yet occurred. This simple fact has far more influence over the way that we live our lives than any other definable fact. It permeates all aspects of all our actions, languages, and concepts. For some reason, at the level of theoretical physics, and metaphysical speculations carried out by physicists, there is a tendency to deny this simple fact. I see it as an unwarranted attempt to simplify the complex, an unjustified application of Occam's razor.
The substantial difference between future and past necessitates the assumption of two distinct types of substance, one proper to the past, the other proper to the future. We cannot assign substantial existence (the existence of substance) to the present, because the present appears to us as a division between future and past, and such a division has not temporal extension. Substance necessarily has temporal extension. So we have two distinct types of substance which bear the labels actual (past) and potential (future). Of course one must be transformed into the other, and this is what occurs at the present, actualization, what we call activity. This produces the concept of "becoming", which refers to the activity at the present.
Now we have another difficulty to overcome. Activity necessarily requires time, temporal extension. But we've already relegated temporal extension to the past and to the future, producing a timeless boundary at the present. The boundary between past and future, the present, can no longer be considered to be timeless, because we must allow that becoming occurs at the present, and becoming is a concept with temporal extension inherent within it, just like substance has temporal extension inherent within. The only logical option is to assume another dimension of time, which is proper to becoming.
So we temporal extension, in the classical sense, which refers to the tradition concept of time. This assumes a non-dimensional point in time, derived from the non-temporal point which separates future from past. We can map out many different time periods, containing duration of time, in the classical sense. But this non-dimensional, non-temporal point, dividing two periods of time, is artificial. And, it is an inadequate representation. It is derived from the assumption of a non-temporal division between past and future, "the present is a point in time". It is inadequate, because from this assumption "becoming" is unintelligible, it defies the laws of logic. This problem with becoming has been demonstrated over and over in different ways by different philosophers. In order to render becoming as intelligible, we must be able to assign to it a temporal order. This is a passing of time which occurs at the present, within that artificial point, that divides future from past. This newly found dimension of time is completely different from time as referred to in the classical sense, because it is ongoing within the point which divides between two classically separated durations of time. The challenge is to establish principles of consistency between the two, to create one concept of time, consisting of these two dimensions.
Earlier on the other thread on this topic, there was a discussion about the interference pattern in the double-slit experiment. I noted that the interference pattern is independent of the rate at which electrons are fired. So I put that question to Physics forum, and also Stack Exchange, and sure enough, the physicists there said that 'time is not a boundary condition' of the interference pattern.
The question I then asked was, are other kinds of wave-functions also independent of time? What is the significance of a timeless wave? That question didn't produce a response. I think it's significant, but to prove it, I would probably have to go and re-enroll in physics and spend 5 years on it. But, intuitively, what it tells me is that the probability wave is not a function of time, and I think that has profound philosophical significance. — Wayfarer
So from my perspective, there really is no "timeless wave". The wave-function must be measured according to the other, undeveloped, dimension of time. It is proper to the realm of becoming, as all energy is. "Energy" refers to a relationship between what actually is (past), and what potential is (future), so its existence is proper to becoming, which can only be measured according to the new dimension of time. What this perspective opens up to the mind, is the vast realm of unknown, which lies on the other side of that newly dimensioned point in time, the present. This is the realm of the not yet actual, the future. Since it is prior to the passing of time at the present, it is truly timeless. Our only means of access to it, is to develop the dimension of time which is proper to the present, becoming and the wave-function. By doing this, we can establish a mathematical relationship between the realm of what actual existence (past), and the realm of potential existence (future, 2nd type of substance). But without this relationship, which can be defined as a unified concept of time, we have no approach to this non-empirical realm.