MarSuper said:
Once again I understand Special Relativity I have read books on it and run through the equations and studied the results. My problem with it is difficult to put in words but I just seem to have this funny feeling in my mind that somehow it is incomplete in someway. Some vitally import way. (1)The constancy of the speed of light bothers me.
(2)Why is it the particular velocity that it is? Keep in mind I already know about Maxwell and permittivity and permeability no need to go there. There is a layer underneath those two constants we need to understand better. (3)Why does light slow down when traveling in different mediums? What really bothers me is the speed limit,(4) this speed limit must be exceedable somehow. Arghhhh!
I've read your posts on the first page and what I see happening is mixing of perspective from the two compared frames.
1. There are a few ways to get the message across of "why a limit", my favorite being to do with causality. Since such ordering is so fundamental it helped me become not only satisfied with there being a "speed limit" but now feel it could not be any other way. So in other words saying c is invariant, for me, is just the same as saying causality is invariant. The latter being so obvious, particularly when considered in the context of physicists making their observations / measurements. Maybe that perspective would make the "speed limit" more intuitive.
2. From this perspective it is not any particular speed, (velocity?) but merely the means for causality to be invariant. Everything less that is just a common typical speed. Trying to create a more clear dichotomy for the word speed when less than c compared to at c ...understand that c is not some physically
attainable speed. ONLY
fundamental forces specifically their "
carriers" travel at that "speed", nothing else*. But less then c is "traditional" speed. Don't let its particular value or fact its distance/time imply to you that it's a "traditional" speed. imo it's a bit of a misnomer to refer to c as a speed.
It is not a logic issue to say you can always go faster, however can never reach c. Maybe that is where it's bothersome? Infinity is a funny thing :) If I understand right this leads to discrete concepts i.e. you can always (infinitely) get a bit closer to traveling 2mph (1.9mph, 1.99, 1.999 so on and so on) without ever reaching 2mph. However in the case of c, the limit is (Seems to be) within the geometry of spacetime itself, which ALL physics plays out on/within; and not some arbitrarily chosen limit like 2mph. Again I like to think of it as being due to causality just cause I find it more fundamental; six of one, half dozen of the other.
3. Note the
fundamental forces specifically their "
carriers" do not slow down. They are always c. There is an "energy exchange" happening as a photon(light as I think you mean, a fundamental force carrier) pops into the the "medium" it's hitting/interacting with an electron(field), and a NEW ONE gets spat out...so on and so forth through said "medium".
4. *c can be (is) exceed, BUT only spacetime itself can (does) exceed c viewed as expansion. But is a different thing (geometry) all together. i.e. outside the realm of kinematics. So me saying c certainly is "exceedable" is smearing two very different concepts together and calling the result a speed greater than c...same sort of trickery as regions being able to exceed c. (shadows for example)
This expansion of spacetime being greater than c has no impact on causality.
So how can causality be maintained (I'm sure you would agree at least IT must) in a universe where fundamental force carriers do not travel at an invariant speed?
Also note the issue with saying "I understand special relativity".