A recent post on a forum I visit got me thinking about this idea.
First, imagine you are on board a high speed train and you have a gun. This isn’t Murder on the Orient express though, this is an experiment.
Say the train is moving at the same speed as the gun can fire a bullet (assuming this speed is the initial velocity of the bullet and the train is moving in a vaccuum, so air resistance is negligible), call this 500 m/s.
Now, fire the bullet out of the window directly ahead. What happens?
Well, without air resistance the bullet isn’t limited by terminal velocity, so the bullet is moving at 500 m/s before it is fired, then gains an extra 500 m/s once it is fired. The bullet is moving at 1000 m/s. Or, with respect to the passenger on the train, the bullet is moving at 500 m/s.
Now, point the gun directly backwards, away from the direction of motion and fire. Again, relative to the passenger the bullet travels at 500 m/s, but relative to an observer standing by the tracks, the bullet appears to be falling straight down.

Then that got me thinking about a similar problem that is all too common in Physics classes.
Imagine you are on board a spacecraft travelling at the speed of light.
You have a torch, you point it in the direction you are moving and turn it on.
What happens?

Well, the light travels away from you at the speed of light.

Now, what about a stationary observer? (that is, the spacecraft is moving relative to the observer)
Nothing can travel faster than light, right?
Right.
Well, the observer also sees the light travel at the speed of light in the direction the craft is travelling.
But then the observer would see the light moving at the same speed as the craft, yet the craft sees the light moving away at the speed of light.
A contradiction?

That’s where Einstein comes in with the Special Theory of Relativity.
This states that light moves at a constant velocity relative to all observers, irrelevant of their velocity or direction.
This is allowed to happen by a phenomena known as time dilation. That is, time slows down the faster you get.

This then leads to the famous ‘twin’ thought experiment.
Take a set of twins, give them identical clocks, leave one on Earth and set one off on a journey round the Universe at very, very high velocity.
When the travelling twin comes back, his clock will be lagging behind the stationary twin on Earth. Thus, he has aged less.

Time dilation is a very interesting concept of both Special and General Relativity, and has had a profound impact on modern Physics, even modern life. In fact, GPS satellites orbitting Earth must take into account relativistic effects, something called gravitational time dilation, when sending positioning data.

It’s been 40 years since the Apollo missions and the first manned lunar landings and I, for one, have been watching the TV programmes quite a bit. It’s all the same old knowledge though, filled with things everyone already knew. The crew of Apollo 11 underestimating their position and having to land in precarious circumstances, the cancellations of the later Apollo missions due to lack of political will, the more recent US revival in space exploration by ‘Dubya’ and his directing NASA to get a man on Mars in the next few decades.

What I found more interesting was the missions planned by other nations. Particularly China.

OK, so many people know that China have a lunar exploration programme. Many people know that China plan to land men on the moon around 2020/30.
What I didn’t know was that following their manned missions, China will begin construction of a permanently occupied lunar base!

If this did happen, it would completely change space exploration. I’m thinking along the lines of 2001 here. Minus the evil computer.
Whoever decided to build an extremely powerful artificial intelligence and give it a BRIGHT RED EYE anyway?!

A lunar base would not only be exceedingly cool, but would offer a ‘recharge station’ for spacecraft going from Earth to more distant destinations, not needing anything like the huge rockets required to take a craft to the escape velocity of Earth. Taking off from the Moon would be a much easier task.

Hopefully once it’s all completed the Chinese will share their lunar base with the other nations, perhaps there’ll even be an Earth-wide space exploration programme and all of the political agendas involved in space exploration will be gone. Maybe I’m wishing there though.

None of this is fully OFFICIAL yet, but the renewed interest in space exploration is definately a good sign of things to come!

Further reading:

New York Times
Statesman.com

I’m currently finishing up recording and mastering another full ‘albums’ worth of electronic music.
Tentatively titled ‘Introspection’, it contains 8 tracks, all of which have previously been available to download in the Music section, but have currently been taken down while I polish them all and finish everything up.

Here’s some artwork.

Track listing.

1. Start
2. February
3. Meridian
4. Krystaal
5. Untitled part 1
6. The Endless, Repeating Cycle (Untitled part 2)
7. Recreate
8. Finish

So I thought this deserved a bit of an explanation.

In the music section, there’s a part titled ‘Project:Alice’, which includes 4 songs at the time of writing.
These songs are titled after the first 4 chapters of Alice’s Adventures in Wonderland by Lewis Carroll. The aim of Project:Alice is to write a song for each chapter in the story, which conveys a message that can be drawn from the chapter. This is done either by interpreting the chapter (semi)literally, as in ‘Down the Rabbit Hole’, which essentially retells that part of the story by way of song; by metaphor or allegory, or by parallelling real world events. An example of the latter is found in ‘The Rabbit Sends in a Little Bill’, which draws a comparison between Alice’s confinement inside the rabbit’s house to the confinement of a human within his own mind by a condition known as locked in syndrome. ‘The song of the dead man’ is a reference to Sylvia Plath’s ‘Berck-Plage’, a poem set in a French hospital, which reads: “This is the tongue of the dead man: remember, remember. How far he is now, his action/Around him like livingroom furniture, like a décor.”
A striking parallel to the story of Jean Dominique Bauby, a sufferer of locked in syndrome.

Over the coming months, I hope to complete more and more of Project:Alice, with the eventual goal of completing a full CD’s worth of music and releasing it through this website.

I hope you enjoy the music.