But we still have a problem with light speed
What if space is not uniform in structure, if so then the speed will differ depending on the "density/permeability/local properties" of the space it travels through. ...

That's a very good point. Is our electromagnetic view of the universe distorted by the mass and the medium through which we are viewing?

All a sort of more subtle combination of distortions due to gravitational lensing, universe expansion and the material through which we are squinting?

Is there enough gravitation that we would be able to see ourselves if we had been there (or would be there) by the time the light path had looped around?

(Conditionals in time are a good source of a linguistic headache. Note the musings of Douglas Adams when faced with a similar conundrum!)

Keep searchin'!
Martin


[edit]

See:

Hitchhiker's Guide to the Galaxy, Restaurant at the End of the Universe (Chapter 15) - Douglas Adams

Time Travelling Grammar

[/edit]

Hello Martin

My own speculation; Im not sure about being able to see ourselves (round the curve) Im beginning to think this universe is fractal. we see but a very very small portion of it.

This brings us to another point or at least another perspective on the matter which may prove to have some interesting outcomes/ or not.

Since we are so busy listening to radio frequencies and observing light waves, infrared ultraviolet etc, then perhaps also tapping into the gravitational distortions would be a wise thing to do. Pure speculation but...Perhaps there's something there in the wave-fronts, perhaps something non-random?

One would have to work out what is "noise" from what is not as I imagine the giant black hole at the centre of our galaxy is creating mammoth gravitational distortions as it swallows stars etc... which will ripple/back-propagate across the galaxy, after all our sun is caught in the "stream" along with most likely 99% of others stars we can see, and is heading eventually to a meeting with the hole...

Maybe there is an analogy with light and sound: If a stationary train were blowing a whistle at 200 Hz the soundwaves would be separated by 350/200 = 1.75 meters. If that train were traveling toward a listener at 50 meters per second the sound would be traveling, still, at 350 meters per second but the waves would be separated by (350-50)/200 = 1.5 meters. The pitch would be increased to 350/300 times 200 Hz to that listener of 233.3 Hz. Out front, the sound would be traveling at 300 meters per second relative to the train but 350 meters per second relative to the listener. The result is a pitch to the listener increased to 350/300 that of what is put out by the horn. After the train had passed the pitch would drop to 350/400 that of the horn or 175 Hz.

---

Einstein's relativity states that the speed of light is the same for all observers, no matter what their relative speeds.

You can watch a good explanation of this in Cosmos by Carl Sagan. In an episode he expains that you can´t add the speed of light to the speed of the object that you are studing.

point of order. The speed of light itself is not the speed limit--the speed limit --called "c" at about 2.977 x 10^8 meters per second is a cosmic speed limit which light cannot exceed.

It is the vector in space time that is invariant.