Why have we ruled out the possibility of finding something faster when we’ve only scratched the surface of space exploration and understanding?
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> when we’ve only scratched the surface of space exploration and understanding?
Physicists make some basic assumptions about the universe. All science has to start from assumptions — your axioms. These are really basic assumptions like:
* The universe is *rotationally symmetric* — that the behavior of an experiment doesn’t change depending on the angle you observe it from;
* The universe is *translationally symmetric* — that the behavior of an experiment don’t change depending where the experiment is performed (all other things being equal); and
* The universe is *time symmetric* — that the behavior of an experiment don’t change depending when the experiment is performed (all other things being equal).
These are explicitly assumptions — we can’t prove them without observing every point in the universe at every point in time from every angle. But, they seem pretty reasonable, and they’ve held so far in our exploration — and most importantly, we can’t really *do physics* as we know it if they’re incorrect! So we’ve made them part of our axioms, and all of physics is built with these assumptions.
That’s important because it means, as we observe the universe through telescopes and radio receivers, we can assume that things work fundamentally the same *over there* as they do here — even though *over there* is a different place *and* a different time (since it takes time for the light to reach us to observe). This lets us do experiments by making a prediction here, and then observing how things are going *over there* where the conditions are right.
So far of those experiments and observations have matched *very* closely to what our standard models in physics predict. This gives us a lot of confidence that our models are accurate. We know they’re not perfect — we know our models have some gaps and inconsistencies, like how general relativity and quantum mechanics disagree a bit on gravity — but we’re confident that they’re not *fundamentally* incorrect.
Now, of course, we can’t *know* that our models are fundamentally incorrect until we make observations that contadict them. For example, in the late 1800s we noticed (among other things) that the orbit of Mercury was slightly different than our models at the time predicted. That led us to doubt the accuracy of Newtonian physics and ultimately to adopt the model of general relativity. Similarly, in the early 1800s we noticed (again, among other things) that light didn’t always behave as our models predicted. That led us, over the next couple hundred years, to develop and refine the model of quantum mechanics.
If we find contradicting observations, physics will have to adopt new models. Maybe we will find some exotic (to us) type of matter that violates our assumptions about spacetime and the shed of light. Most likely, to start with, we’d try to incorporate it by tweaking our existing models. They’ve done a very good job so far, so we’d like to keep as much of them as we can. But, if we can’t make it fit — like the orbit of Mercury and the behavior of light couldn’t fit in the Newtonian model — we’ll have to come up with a new model that fits everything we’ve observed so far, *plus* the new stuff.
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