Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: namaan on 12/01/2012 23:43:06
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I don't mean to hog the board with all these topics, but I get bursts of interest in different fields and the field of the moment happens to be physics ;)
So you get in your car and know of two routes to get to your destination. When zoomed out far in the map, both routes look nearly identical in shape and length, so you imagine they should both take the same amount of time. But what you fail to realize is that if one zooms into route A enough, it becomes clear that it is at a smaller scale much curvier than first perceived. Whereas with route B, it appears to be going pretty much straight to the intended destination even after zooming in.
So if you take route A, you will in fact have to travel a lot farther than you expected and thus it takes you a lot longer to get to your destination. But if you were looking at your location on your navigation display when zoomed out enough, it would appear that you are going in a straight path to the destination, only far slower than if you took route B. (I'll see if I can create a diagram if anyone needs help visualizing this).
Now when we talk about time dilation, what gets me is even as we say that time is the 4th dimension, yet don't treat it as we do the spatial dimensions, I have to ask: why not? As far as interpretations go, the standard explanation of GR time dilation makes sense and is perfectly reasonable to me on most respects. But just the fact that the dimension of time is treated as somehow different seems to me as a bit unnecessary.
So I have to ask, why can't we say that particles at the quantum, or perhaps even the planck scale, are having to travel farther to get to their intended destination then perceived/expected. And if they have to travel farther in the 4th dimension the faster they go, than certainly they must take longer and longer to get to the destination, no?
I realize of course, that the most obvious answer to this is that there is no experimental evidence for this. But is there really evidence for a particular mechanism that explains time-dilation in a non-spatial 4th dimension? But actually, ignoring the evidence part for a bit, I'm mostly just wanting to ask, is this a reasonable interpretation, or does it conflict in some fundamental way with established physics?
Ok, this OP is a bigger than expected, thanks for reading it those of you that did!
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You can't get around the results of SR, which requires some dimension doesn't behave like space. If you require that time and space do behave alike and introduce a 5th dimension to account for the results of relativity, then your 5th dimension now won't behave like the other 4 and it won't be observable.
The reason we don't do this is that when you're building a model to explain experimental results, you want to keep it as simple as possible. You can always add variables to the theory so long as they don't change the measurable predictions it makes, but it doesn't make sense to do so.
Having said that, there are some effects (quantum gravity) that apparently can't be explained with a 4D theory. One possibility to deal with this is introducing extra dimensions, but this is only being done because 4D isn't sufficient.
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The reason we don't do this is that when you're building a model to explain experimental results, you want to keep it as simple as possible. You can always add variables to the theory so long as they don't change the measurable predictions it makes, but it doesn't make sense to do so.
I get that, but I was spurred to consider the idea for the same reason of keeping it simple in conjunction with other conjectures. Not withstanding, the idea that, at least existentially, we don't really seem to need another dimension strictly devoted to serving us a clock in lieu of existing phenomenon such as entropy and reference frame invariance of c that seem to do this job in their own way.
But I'll spare you speculation atop speculation; this topic is already border-line New Theories material ;) [Edit: Not that there's anything wrong with that of course. I've posted there a few times myself.]
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Fair enough. In certain cases, it could be the simplest explanation, but most of those cases probably do belong in New Theories because of their content, as you say. :)
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Nam, Einstein spent a lot of his later years working with exactly that. A five dimensional theory binding the four dimensional reality we percieve into a whole concept. And the math he used for that seems to be what modern string theory uses too, although I'm no expert on that.
The problem with introducing inferred 'dimensions' is that you introduce new complications, and most certainly probabilities, as well as possibilities as you 'upgrade' the complexity of the math getting you to that 'TOE' (Theory Of Everything). What I see it to have to do with is the assumption of us all 'somehow' sharing a same universe. If you want it (the universe) to be a box of sorts where everything we see and measure being 'cogs' then you will need to go up in complexity. But you can also work from a assumption of Einsteins 'four dimensional reality' being exactly what is, although defined from 'locality'. That will make all observations and measurements you do valid for your 'piece' of the four-dimensional continuum, as mine will do for me.
Then what, to me that is, seems to bring into one 'whole global' SpaceTime is radiation. That's our curtain of light describing our reality. And radiation is in Einsteins description and all experiments testing it, that I know of that is, a 'constant'. Explain the constant and we will be far on our way, because that is our 'local clocks' too. 'Times arrow' and 'c' fits all too well together from locality to be any other way as I see it for now, that is :)