Food for thought?

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This seems to prove that lightspeed cannot be invariant:

Looking into the distance to your right, you observe a tube shaped space craft heading towards you. By those magical means available only in thougth experiments, you determine its size and velocity, and observe its on-board clock (which may well be running slower than yours).

Looking to your left, you find another such craft heading towards you, which, other than for direction (which doesn’t matter in GRT, right?) appears to be identical in every respect to the first.

At that moment in time when they become exactly aligned, nose to tail, as they pass by you, a pulse of light strikes the rear of the first craft and the nose of the second, and then travels the length of each tube.

Let me just double check here ; according to GRT, both these craft experience light as c (which is mathematically plausible in certain circustances) and are of the same lenght, and have clocks travelling at the same rate, as far as you the static observe is concerned (do we need to consider at this point how their clockrate appears to each other ?) and so the pulse of light should exit both at the same instant.

Still with me so far ?

The problem is that it takes a finite time for the pulse to traverse each craft, during which they will have moved a finite distance, one reducing the distance the pulse must travel to do so, whilst the other shortens it.

So what are we to believe here ? That the pulse exits at the same time and place from the crafts’ point of view, whilst doing so at a diferent place/time from your view point ?

Do you suppose, perhaps that that part of the pulse in one craft slows down (whilst remaining at c?) whilst the other speeds up (relative to you, dear observer) whilst remaining at c, in order to exit simultaneously (oh dear, that word again : should we take it the concept is meaningless, or is the real problem that GRT simply cannot deal with it ?) ? Lets hear it for intelligent considerrate light pulses !

But wait ; given their near light-speed velocities, these craft are bending space (whatever that means) right? But which way ? Presumably in different ways for each craft...even though they are occupying more or less the same space ?

Time folds can change rates of speed and time for an object.

I often wonder about this and neutrinos.

“ The low mass and neutral charge of a neutrino make it perfect as a probe for exploring places other forms of radiation can’t penetrate. For example, neutrinos detect conditions inside the core of the Sun because most of them pass through the intensely dense material. Meanwhile photons (light) get blocked. Other targets for neutrino probes include the Earth’s core, the galactic core of the Milky Way, and supernovae.

In 2012, scientists sent the first message using neutrinos through 780 feet of rock. Theoretically, neutrinos allow for transmission of binary messages through the densest matter at nearly the speed of light.”

I find that fascinating!