Ah so now you clarify that a same state past actually has nothing to do with computers?
Ah, no; I said nothing of the sort.
By saying it is the same method or system that makes computers as makes models for the past, what you are really saying is that one assumes a same state past and uses that in the way we use other things here in the present. Except it is all belief and theory, not in the real world. The computer is in the real world.
Nope. We have physical models that we can use to do all kinds of stuff, including making computers. We can use these models to make predictions about things in the past. When we do that, and go and look at stuff that we think is that old, we find that the predictions hold good. Doing this many times in different ways gives us confidence that our models are reasonably accurate and can tell us about the past.
For example, if you plant a bunch of trees, and every year you cut a few down, and see that a new ring grows in the trunks every year. You might also see that the rings laid down in wetter years are thicker than the rings laid down in drier years. You think that this could be a useful way to tell roughly what the climate was like even before you planted those trees, so you find older trees with known planting dates and compare the rings, and you find the recent rings match those on your trees, but there are earlier rings. You count back through the earlier rings and find a few wide ones and a few narrow ones, and go to the library and look up the historical weather data for the years corresponding to those rings. The historical weather data agrees with the width of the rings - wet years for wide rings, dry years for narrow rings. Now you have a rough guide to the climate over the life of a tree - if you know when it was planted, or you can match some of its rings with a tree of a known planting date (you can also do other tests on tree rings, e.g. to find out about changes in the gases in the air that year, and so-on).
This is the kind of thing I'm talking about - except that tree rings are just one of many independent methods of finding out what the past was like.
Bingo. FROMM what they observe IN the world NOW!! You admitted it.
Of course; obviously you can only observe in the present. But from this, you can infer the past. You know you have a personal past because you have memories. When you look at your friends, you can infer that they had grandparents, although you weren't around then to see them; if you see a photo of those grandparents, you can tell what they looked like. If you dig beneath the foundations of an an Aztec temple and find a burial site, you know the people buried there died before the temple was built, and so-on. It's not rocket science.
When we apply that to say, the universe, we end up with 95% being unknown so called dark stuff. That may seem explanatory to you, it seems ridiculous to me!
The models we use today explain and predict what we have observed better than all previous models. That doesn't mean we know everything. We looked out of our celestial back-yard and - as expected - discovered many new things. Some were easily explained by our existing models; some took a while to explain using them; some remain unexplained because we don't yet have enough information about them. It's possible that the models needs some tweaking to explain dark matter, but it seems likely that it consists of particles that do fit into the Standard Model (Weakly Interacting Massive Particles or WIMPS) - we don't know yet, because at present we don't have enough information - we can only detect its gravitational effect.
Other things also you explain using earth realities, but we could explain them many other ways. Heck a village idiot can explain things, the trick is to be right!
In science, there is no strictly 'right' explanation, there is just the
best model or theory - one that explains more observations and makes more useful predictions (and, preferably, is simpler and more elegant) than any other.
The underlying basis for many models or theories is mathematical or logical, so they can be said to be 'right' in as much as the conclusions follow logically from the premises, given an appropriate context. Much of physics (e.g. statistical mechanics) is like this, but in practice, even theories with logical or mathematical foundations may only partially explain real-world behaviour.
For example, the principle underlying Darwinian Evolution is basically statistical: populations with hereditary variation will tend to change over time in response to selection pressure. In that sense, it is 'right', but Darwin's original theory, though based on that principle, was later found to be inadequate in various respects (because the precise mechanisms of heredity and variation were not known at the time). In the real world, it is far more complex than he imagined, and so over time his theory morphed into the 'modern synthesis', and is now known as 'evolutionary developmental biology' - but it's still based on the same evolutionary principle.
In a slightly different way, Newton's mechanics provided a physical model (based on mathematics) that explained and predicted everything from the fall of an apple, the trajectory of a musket shot or cannon ball, to the orbits of the planets. It wasn't until our instruments became much more refined that we realised that Newtonian mechanics was an approximation of a more general theory, Einstein's Relativity. Newton's model wasn't wrong exactly, but applied to a universe with absolute time and Galilean invariance, and although it looks like that at human scales and speeds, we discovered that the universe we observe isn't really like that.
Not really. It can be welded and molested into fitting the belief system that has it old. Then it will look old in the tapestry of imagination it was woven into for the folks who chose to swallow, and limit themselves to that little belief set.
Created fish and animals and man evolved and rapidly, so finding a walking fish is no problem at all. There you go trying to cram that computer in again, as if it were on your side. No Frumy, no.
You can say that, but in practice, the model works - although finding a particular transitional form of walking fish turned out to be, in reality, a difficult problem. Fossils of fish with strengthened front fins were known from rocks dated around 380-385 million years old, and fossils with well developed limb-like front fins were known from rocks dated around 360-365 million years (and never vice-versa), so Shubin, Daeschler, and Jenkins proposed that to find the intermediate form they were interested in, they should look in deposits dated around 370-375 million years. Exposed deposits dated to that age had been mapped years earlier in Northern Canada, so they took an expedition there, and spent 10 years digging. Eventually, among many other fossils of that period, they found an intermediate form that matched their prediction. That intermediate form isn't found in earlier rocks or later rocks (as in tens of millions of years).
Now you can say that all those rock layers and all those fossils were laid down far more quickly than tens of millions of years, and far more recently than 300-400 million years ago; you might say that all the fossilized creatures evolved and all the rock layers were laid down in a few thousand, or a few hundred years; and that it all happened a few hundred thousand, or a few thousand years ago - or even
last Thursday, that we can't prove they didn't, and therefore we're wrong; but as far as the science goes, all that counts is that the multiple threads of evidence found by tens of thousands of researchers over hundreds of years, and all over the world, are consistent with the model that dates them to 300-400 million years, and that there is no consistent evidence supporting any other model. If sufficient contradictory evidence is found to make that model untenable, then the model will be changed or replaced appropriately.
In other words, as far as the science is concerned, if it looks like a duck, walks like a duck, quacks like a duck, lays eggs like a duck, and swims like a duck, we'll provisionally take it to be a duck until some evidence to the contrary makes it unlikely to be a duck.
Science is, strictly, descriptive; but for many people, the models and theories it provides - based on coherent and consistent evidence gained from observation and measurement of the world around us - are a better guide to reality than the many conflicting stories & myths about it, that are often incoherent and almost always inconsistent with those observations and measurements. YMMV.
I think I've said enough on this now