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Posts Tagged ‘travel’

Time and relativity

August 30th, 2007 Comments off

I was reminded today of the theory of relativity, and in particular the idea that funny things start to happen when you try to travel as fast as light. The idea is that in order to go as fast as light you need nearly infinitely large amounts of energy to get there and will suffer an effect known as time dilation.

For example, suppose you travel around the earth as fast or faster than the speed of light. In theory, you could move fast enough to get to the point where you started before the light you saw then had reached you, hence the effect of time travel.

What I often have to remind myself is that its not about where you’re coming from, but where you are going to. The destination. Start a stopwatch on yourself and one at the destination at the same time (never mind the logistics of that) and when you get to the destination, they should show exactly the same time regardless of how quickly you got there. It’s not about the time that you think the destination has from where you are, but their time (assuming you use the same type of clock).

So when someone looks at the stars and says the light we can see left there umpteen years ago, thats just a feature of the story light tells. If we traveled faster than radio waves, which is a good deal slower than light, the same effect occurs. It’s just not true time travel.

Categories: My brain hurts Tags: , , , ,

Raglan beach

January 24th, 2007 Comments off

Went to the beach last weekend with the folks and got a few photos of the surf you might like to see. My son had never seen the surf before, so he was pretty nervous, but he loved the sand and he got to play with his new bucket and spade, which delivered sand to all the most inappropriate places with rapid abandon!


The tide was just starting to pull out by the time we left the surf beach, which you can see here. There is just so much beautiful landscape that I was hard pressed to pick the best pictures.

Back into it…

January 3rd, 2007 Comments off


Well the holidays are pretty much over, back into it!

I went for a trip with the folks to visit my sister down south yesterday. The sun was shinning, with a gentle breeze, and we saw heaps of neat scenery on the way. Didn’t get a lot of photos, but there were a couple that worked kinda…

The wires in the background of the second pic are the power cables for the main trunk train line.