Consider a bullet. I had one sitting on my dresser as a kid – a Civil War Minnie Ball. Toss it into the air. It tumbles. It hovers, for a split microsecond, pointing at you as it falls. Consider that same bullet in 1862 (I found it on a farm near Antietam). Consider standing in front of the line of Blue (it was clearly a Yankee bullet) with your fellow Virginians. Consider that same bullet again. Fired from a Springfield, heading your way. Take a split microsecond, same length of time as before, and focus in on only the bullet. The situations are almost indistinguishable if looked at on a short enough time scale. The 1862 bullet points at you in the same way the modern one does. In that split microsecond, an observer who happened to just drop in and observe only the bullet would be hard pressed to decide which situation he or she’d rather be in. Practically the same mass of metal. Same shape. But look closer. The 1862 bullet should be warm – evidence of the kinetic energy stored in it. The present bullet should have a coat of oxidation. But there were bullets fired in 1862 that had been dropped in the crick the month before they were fired, and the modern bullet might have been sitting in the sun for a while. There’s always something for the naysayer to latch on to. But take another snapshot a couple of milliseconds later, and the difference between the two situations is instantly clear – the bullet in 1862 has traveled a lot further – and in a much straighter line than the arc of the falling bullet tossed from your hand. Now which situation would our hypothetical observer rather be in?
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