Breaking the Speed of Light

(YouTube link)

One-Minute Physics explains how to break the speed of light by pointing a laser at the moon. I think this boils down to appearance vs. reality, but I may be mistaken. Anyway, it sounds fun to try! -via The Daily What Geek

Right, it's simply in perception. Nothing, including light, is moving faster than the speed of light. The gap between individual photons increases, but those photons are still reaching the moon at the same speed. Our brain fills in the details to assume unbroken movement from one place to the other, just like how TV animation works.

On a TV, if you illuminate one pixel then illuminate the one next to it, it appears as though the image is moving. If you do the same thing but skip to every second or third pixel, the image appears to be moving faster. Every tenth pixel, the image shoots across the screen. Nothing is actually changing speed; we just see the gap increase.
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@wiseguy. If you actually pointed a laser at the moon, you wouldn't even get the perception that the person in the video imagines you would.

If you had a laser beam strong enough to be visible after reflecting off the moon, and you moved the beam from one part of the moon to the other, it would take about 2.5 seconds for you to see the beam move on the moon's surface.

That's the amount of time for the beam to reach the moon, and return.
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"If a laser beam is swept quickly across a distant object, the spot of light can move faster than c, although the initial movement of the spot is delayed because of the time it takes light to get to the distant object at the speed c. However, the only physical entities that are moving are the laser and its emitted light, which travels at the speed c from the laser to the various positions of the spot. Similarly, a shadow projected onto a distant object can be made to move faster than c, after a delay in time.[38] In neither case does any matter, energy, or information travel faster than light.[39]"
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Again, completely incorrect.

When the person moves the laser, the photons that are currently arriving at the moon do not move.

The photons exiting the laser take over a second to get to the moon, and arrive at the second location.

Take a hose and spray something far from you. Then flick your wrist and aim to another spot on the driveway. It takes a second for the water exiting the hose to catch up to the new target. Same idea.
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The usual description is to look at a wave hitting a beach. If the wave is at a slight angle to the beach, the apparent speed of the wave traversing the beach far exceeds the speed of the wave's approach. Given a sufficiently straight bit of beach, and a shallow enough angle, it's possible to exceed the speed of light.
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There is a serious problem with the author's thought processes. The spot never moves, because the spot is constantly renewing. You see the impact of the light on the moon, but as it moves what you are saying is effectively a very large number of different spots. Just like those pixels on your computer monitor.
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So, if I hold up a model train and then someone in Japan holds up a model train a split second later, by this video's definition, the train has broken the speed of light. This video is really just trying to confuse rather than clarify..
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When I was a kid and I first started to study physics and maths I would occasionally think I'd spotted huge holes in accepted mathmatical and physical theory. However I was smart enough to realise that what I needed to do was work through my thinking and find the flaw in that. I always found the flaw in my thinking before I found the flaw in the accepted thinking.

This guy isn't that smart.
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