| Kasz216 said: It wouldn't completly. It really depends how the universe expands though. Like imagine the universe was a pokadotted tabelcloth... with the dots being planets. Now lets say an ant is on one dot crawling to another at a consistant speed... but then the tablecloth is opened up more, increasing the distance between them. That ant is still moving at the same speed, but since it takes longer to get to our dot then it did in the past.... it gives the illusion of it "slowing down". If you thought earth was created 6,000 years ago. One could argue that we were previously caught up in such a "dark energy" wave but now are out of it... so that light that is reaching us now, that is more then 6,000 years away... used to be much closer then 6,000 years away... but the earth was caught up in a wave that moved it say 8,000 light years in what would take light to move 2,000 light years. (made up numbers for an eaxmple.)
It does seem unlikely though i mean light does "slow down" or has the illusion of slowing down I should say, but that's in a situation where space is contraced, like with strong gravity fields and the like. If anything the speed of light might have increased if space really is like a tabelcloth and there is only so much of it. Since as space would stretch it would look as if the speed of light was increasing. Though really it would just be moving the same speed along a medium that was stretched. Wait... how does light slowing down help their arguement again? Thinking about it logically... that light is speeding up seems like the arguement they'd want to make. |
That is kind of the argument they want to make in a manner of speaking. They assert that light can be faster than it is today and that in the past it has been. Either way it is the idea that the actual speed of light can increase or decrease which is the impossible thing for me to believe as it would require changes in the fundamental laws of physics.
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I understand your analogy about the table cloth, but all that does is pander to the changes in the speed of light being an illusion.
It's like the rubber sheet analogy (in part) which explains gravity, where space curves around high mass objects, and all objects are in constant free fall. If I hold the rubber sheet out and place a bowling ball in the center, then the rubber sheet will curve around the bowling ball, and the sheet will be stretched under the weight.
If I start to roll pingpong balls across the sheet, then the place where I roll them will determine the path they take. If they are rolled close to the bowling ball then it will take longer to travel across the sheet as it has to compensate for the stretched curvature of the rubber sheet. However, if I roll them further away from the bowling ball, then the rubber sheet is less stretched and the pingpong balls cover the same distance in less time.
The thing is I can roll pingpong balls at the same speed but some will take longer than others to reach the other side of the sheet.
The same could be said for photons travelling past a black hole or other high mass body. The photons don't slow down they just have longer to travel the closer they are to the high mass object (assuming they don't reach event horizon). The speed of light hasn't increased or decreased, it has remained the same. But it has taken some photons that are travelling close to the high mass object longer to travel from point A to point B than others traveling further away.
The speeding up and slowing down of light would just be an "illusion".
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But what young Earth creationists say is that it is nothing to do with the illusion, and that the actual speed of light has been faster. Because a few black holes here and there wouldn't really effect the time of which photons have traveled over billion's of light years. For their argument of the Universe being a few thousand years old, they would have to assert that the speed of light in the past was millions of times quicker than it is today. It's extremely unlikely in my book.
Ask Angrypoolboy, he's a young Earth creationist from what I remember, he'll know more about their arguments than me lol.
