Thursday 31 March 2011

Running up to the rays of the sun

Trying to understand nature when he was young, Einstein imagined running alongside a beam of light, and he wondered, if he did, what would he would see light do? His conclusion was that he would see light stand still as a wave. I suppose the way surfers might see a frozen wave beneath their feet.

But years later, through the theory of relativity, Einstein blocked off that possibility of reaching the speed of light. Anything slower - or faster - than light can not reach light, and light can neither speed up nor slow down. Assuming that we are massive creatures, i.e., creatures with mass, to get to the speed of light is to acquire infinite mass. Now, this isn't the sort of thing you get by eating a lot of sweets. Nor does it mean we magically acquire mass like a mythical stone in a folk tale or the child christ in the legend of St.Christopher. It means that, the faster something gets, the harder it is to make it even faster (I think that is all that is meant by inertial mass in relativistic physics). So, this is something which gets harder and harder as you do so, each time requiring more and more energy for the same increment of light-speed. And, no matter how fast you make it - 0.99 the speed of light (0.99 c), 0.999c, 0.999999999999999c - you can never make it hit light speed.

Nothing massive can catch up with light.

For faster-than-light particles, tachyons (we slower-than-lights are tardyons), no matter how much energy you put in, you cannot slow them down to the speed of light. They are always faster-than-light. Whether tachyons exist outside the realm of Star Trek, i.e., in the actual universe, the universe where people can't fly around space in plastic and tin boats - that is not something that's been in any way proved.

Nothing massive can be caught up by light.

It's also not clear to some physicists that there could be anything 'like' moving at the speed of light.Once we define the motion of another massive body, through transformation equations (I think they're called), we can use the data about the universe as observed within our own frame of reference to describe the universe from the other frame of reference. But, at the speed of light, such equations break down.

For example, the length something has along its line of motion - e.g., a rocket ship's length from nose to tail as it flies forward - this length is shorter for an observer in another frame for whom the ship is moving. But, at the speed of light, this length is zero. It disappears. At least according to the equations.

But worse - and for me, this was worse, and left me grumpy and disatisfied - the time between two moments, e.g., the time between seeing the rocket pass and checking your watch, however quick you do it - this time, once translated into the 'frame' of light - this becomes infinite.

Does this mean that, from the speed of light, all time has stopped and everything is flat? I thought that was what it meant when I first started working on time-consciousness. Then I got another interpretation. It's this: no, it doesn't mean those two things; it means that there is no physical description of spacetime structure from the speed of light. Physical lawas do not provide any description.

Perhaps this is why I've also heard it said (and no I can't cite sources; ask a physicist) that there is not, in a sense, any such thing as light. In the way that an asteroid occupies the 30,000km/hour inertial frame relative to earth, and I occupy the rest frame relative to this couch, and this couch occupies the 40miles/hr frame relative to a car passing by outside, nothing occupies the light-frame. If so, photons don't exist-

Or if they do, they are quite unlike anything we can otherwise describe.  And this 'quite' is quite a 'quite' - I mean, it's not a quiet 'quite'; it's not a quitting 'quite'; it's not a quasi-'quite'; light is seriously QUITE. Unlike, anything, massive.

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