One of the reasons <jim park /> is the best friend I’ve ever had is that he never seems to grow tired of my meaningless mental gymnastics. The less bearing a puzzle has on anything meaningful in my life. The cool factor of an idea seems to have an inverse relationship to the useful factor.

One of our long running games is “Einstein was wrong”, in which I attempt to invalidate No sniplet called einstein and Jim attempts to validate him. Sometimes, as is the case now, quite some time can pass between volleys. I suspect that even now he may be quite surprised at how long I can ponder something and then jump back in and pick the thread right back up.

I’m frequently surprised that he plays along. No one else will.

We’ve played this game largely over the phone and on <facebook />, but I have decided to launch this volley here. Please not that neither of us is a physicist, nuclear or otherwise and we only find certain aspects of practical applied physics interesting. The worlds you can create in your mind are infinitely more fascinating, perhaps because your never have to poop there.

One of the core proofs Jim has offered is the example of two observers, a train and a flashlight.

Jim’s story differs from the stock proof of the relativity of simultaneity where the train is struck simultaneously in both the front and the back (or fires photons at a central receptor from the front and the back) as it passes a platform on which a (relatively) stationary observer waits having deduced from the weight of the textbook he has found himself in that something momentous is certainly going to occur here on this page at this time.

Jim’s story, in accordance with Jim’s approach to life, is simpler, less contrived and could be written out fully without becoming a danger to the skulls of passers-by were it perched precariously on some very real and relatively high bookshelf.

In this scenario we have the train, ever ready to serve as a prop in the relativity games. On the train is a passenger who has a flashlight and two mirrors. The passenger shines the light through the top mirror , it reflects from the bottom mirror back to the top mirror. according the frame in which the passenger observes the light it travels in a precise line straight down to the bottom mirror and straight back up the same path back to the top mirror.

Unknown to the passenger there is a sniper on a hill watching the train through a high-powered Zeiss 6-24×72 Sniper Scope mounted on an M107 Long Range Sniper Rifle, .50 cal. The Sniper sees the light shine down through the top mirror at an angle and reflect back up at an equal and opposite angle back to the top mirror, forming a “Vee” shape.

Relativity, Jim says, means that both of these observers are correct. For the passenger, the light really did travel in a straight line and for the sniper it really did travel in a “Vee” shaped path. This would also, of necessity mean that it traveled farther when observer by the sniper than it did when observed by the victi… err… passenger. So either the light was moving faster for the sniper, or time was moving more slowly.

Einstein tells us, and the world’s physicists agree, that the light traveled both paths and that it did so at the same speed, because the speed of light is, apparently, the only absolute thing in this relativistic universe. Further, since you are not permitted (because you simply can not obtain the permits to do so at any town hall in all the land) to add your speed to the speed of light, the light could not have increased its speed to make the trip in the “vee”.

<pythagoras /> taught us that the lines along the outside of the triangle are longer than the line up the middle, so there is only one conclusion. The light had to travel the extra distance at the same speed it always travels at, but do so in such a way that it completed its journey while the mirror was still there, or rather not until it had moved to where it was going, or, well, actually, both at the same time.

We now pause this blog post for this commercial message from our corporate sponsor, <bristol-meyers squib />

Light, it seems, is even more stubborn than either a North Going or a South Going Zax, and it cares little for the ways of those creatures on the prairie of Prax. If light were traveling along the trax of either of these Zax it would simply keep going, never slowing, not even nodding a nod as it rushed on at its constant velocity, just as it had since it was a lad in light going elementary.

Now, this is the point at which I usually point out to Jim, that observation isn’t everything. It is perfectly possible, and quite often unavoidable to be just as sincere as you are wrong. Just because you have observed at thing in a certain way, or indeed, because you had not observed it in some other way, does not of necessity alter the actual conditions of the thing or the event which drew your attention to it.

Quite to the contrary, a great many things occur constantly giving not a whit whether you observed them correctly, incorrectly, or even if you observed them at all.

To wit, the passenger is just as dead despite never having observed the sniper or the .50 cal. half metal jacketed anti-materiel round that caused his head to cease all function in less time than would have been required for his no longer functioning brain to register the fact that something had occurred.

Indeed, the passenger, failing to observe the trajectory of the missile was not spared at all, and even had he been somehow cognizant of the firing of the rifle, his observation of a curved path, rather than the relatively straight one observed by the sniper would not have caused the round to miss, and he would still be dead, even with his attempt to alter the reality of the situation by pretending he was going faster and time was going slower and that all of that might have any real or practical meaning to anyone just trying to get on with living their lives, feeding their children, paying their bills and trying to squeeze in a good laugh or two along the way..

I’m going to just skip over mentioning all of that this time though.

This time, I’m going to ask a simple question. What seems more likely to you.

On the one hand we have the idea that our frame of observation alters the facts of a occurance (even to the point of altering sequence and simultaneity) in some infallible way, or does it perhaps seem more likely that we observe absolute occurences in different way, altering not the absolute occurence, but merely our experience of it.

If two people walk into a room set at a constant temperature of 38° farenheit, and one person, accustomed to colder temperatures observes that it is a little chilly and another person, accustomed to warmer climes observes that it’s freegin’ freezin’, we instantly realize that the two people experience 38° differently, we don’t try to come up with ways to explain that the 38° is somehow different, but only that the two people experience it differently based on their referential frame.

While we might not insist that both are wrong, we would also not insist that each was right when one proclaimed that the relativistic temperature was 52° and the other that it was 27°. Well, okay, the whether men like to play around with things like wind chill factors, but that’s another story for another time about another thing we usually don’t even realize we don’t actually understand.

Remember, kids, not seeing the sniper doesn’t make you less dead.