Maybe this has been addressed...

So...Einstein's theory claims that the speed of light is the absolute limit of speed.

I've heard anecdotes questioning it with the example that if one were on a vessel, traveling at the speed of light, and walked from the back towards the front...one could break that law. It was easily explained away as simply impossible to do.

But I have another question for any physicists within the community, though I'm sure it's been asked before, and addressed, by people much smarter than I am. I'd like to ask those people to explain how it isn't breaking the rule.

If an object, traveling at the speed of light, is approaching another, traveling at the speed of light towards the first object...aren't they closing that distance at twice the speed of light? In all honesty, that would break the light-speed barrier, wouldn't it?

Good question, but...explainable (please comment) 9
Good question. You stumped me. 5
You're a dumbass. Go back to bed. 3
I like pudding. 9
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Comments ( 23 )
  • anti-hero

    You are barking up the wrong tree on IIN.

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    • charli.m

      "But I have another question for any physicists within the community, though I'm sure it's been asked before, and addressed, by people much smarter than I am. I'd like to ask those people to explain how it isn't breaking the rule."

      This bit is comedy gold :D

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      • anti-hero

        Might be the VegHead that eats pork.

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        • charli.m

          I like him :)

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        • Might be ;P

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      • I have got the marriage papers.

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  • donteatstuffoffthesidewalk

    caint yall figger out that speed has two bitpieces? time and distance.
    if thatall speed stays constant like it will to themall observin travelers then mebbe the speed or distancesll be gettin all distorted n mishmashed.
    I think lots bout this kind a stuff while im firin that there still for shine

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  • tittle

    On a vessel travelling near the speed of light, someone can actually walk from the back to the front.
    A beam of light can also travel from the back of the vessel to the front. So someone on the vessel sees this beam travel the length of the ship, going at the speed of light, c.

    However somebody outside the ship watching it fly past at near light speed also sees the beam of light. They see it travel a much further distance (the length of the ship + the distance the ship has travelled). They time how long it takes and also calculate that the beam was moving at c, the speed of light.

    So the two observers calculate the same speed, but measure different distances travelled by the light beam. This means that the two observers will disagree about the length of time it took for the beam to travel from the back of the ship to the front. The time interval will be shorter for someone on the ship compared to someone on earth, say, and at rest relative to the ship.

    So time is a relative concept and depends on the frame of reference of the observer.

    I can't answer the actual question. But I think that the time dilation would somehow account for it.
    For someone looking at the two objects approaching each other, there isn't really a problem. But for someone on one of the objects, you would think that it would "see" (if it could somehow perceive it) the other object approaching at faster than the speed of light (which Einstein says is impossible).

    I'm not exactly sure, but basically time and length distorts in different frames of reference which accounts for the fact that nothing travels faster than the speed of light.

    I think.

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  • IncludedSos

    Here's my explanation.
    Your question? Simple. Indeed you could say that the space between the objects was decreasing faster than the speed of light, but that is merely space itself, no objects within it. It has been recognized that space itself can go faster than the speed of light (see inflation). If you're referring to one observer calculating the other's speed, then it's because when objects accelerate, their time slows down relative to everything else. So when you're going the speed of light, people would only observe you moving slowly. This is called time dilation.
    The question you mentioned? Also simple.
    First you need to know why you can't go faster than the speed of light in the first place. As objects accelerate, they gain mass. As it gains mass, it needs more energy to accelerate. By the time you hit the barrier of the speed of light, you would require infinite energy to accelerate more, because you would have acquired infinite mass. If you were on a train going 99.999999......% the speed of light, and attempted to run across to break the barrier, you couldn't, because you wouldn't have the energy.

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  • Incomplet

    I'm not one hundred percent certain about my explanation, but if we change the example we can see the situation in a clearer perspective.

    Consider if a flea was on a cheetah. The cheetah can sprint at break-neck speed, and (theoretically at least) the flea and move further up the cheetah's back. The cheetah moves from point A to B.

    The flea however, doesn't travel from point A to B on its own accord because it truthfully only moved from point X to Y on the feline body. But during that period the cheetah moved from A to B.

    Speed is calculated by dividing distance by time. Assuming the area the flea moved was more than the area the cheetah sprinted but they both took the same amount of time, the cheetah is still faster than the flea.

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  • FJK_frm_AK25

    This conversation is beyond me

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  • AndrewDR

    if you were traveling at the speed of light, you would not be able to recognize anything being the light produced or reflecting from other objects would be distorted.

    in addition, if an object with a mass... aka you... were to travel at the speed of light, your mass would become infinite. which is not possible. You would not survive. Only things with 0 mass... aka light... can travel at light speed.

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  • thegypsysailor

    Your car is still only doing 60. Closing speed (you say approaching but they are the same) is indeed 120, but still, neither car is doing more than 60, period.

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    • Not even close.

      If you're heading eastbound, on the equator, add approximately 1000mph to your speed just as it equates to the rotation of the Earth on it's axis. That doesn't even factor in the speed that the Earth revolves around the Sun, the Sun around the galactic center, and the galaxy in relation to our local group.

      So...you're going 60mph in relation to the ground beneath your wheels, but that's irrelevant to this topic.

      ...Got it?

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  • thegypsysailor

    If you are driving your car at 60 mph towards another car doing 60 mph at you, how does that change the speed you are going? It may create a "closing" speed of 120 mph, but still neither car is exceeding 60 mph.
    Got it?

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    • Agirlsbestfriend.

      the other car will be approaching you at 120mph. Compared to you, that car is moving at 120mph.
      You'd definitely feel the difference.

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  • tittle

    I think about this stuff when I masturbate. IIN OP?

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  • GeeGees

    Just no cause

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