A Reading Recommendation: A Briefer History of Time

I wouldn’t consider myself a massive physics fan and was more than happy to step away from the subject after finishing my GCSEs, having said this, I recently read Stephen Hawking’s ‘A Briefer History of Time’ at the recommendation of my fabulous maths teacher, since it ties in nicely with some of the themes covered in the mechanics modules of A-Level maths. I was sceptical to read it at first, thinking ‘This is Stephen Hawking, director of research in this field at the University of Cambridge – as if I’m going to understand a word’ but was pleasantly surprised to find the content manageable and soon found myself glued to every chapter!

Although, some of the topics covered when straight over my ‘non-physicsy’ head, certain elements literally blew my mind:

Disclaimer: THESE ARE NOT MY IDEAS! Everything mentioned below is lifted entirely from Stephen Hawking’s work.

•          Firstly, the concept that there is no absolute space. To contextualise this, I will describe the example, utilised by Hawking in A Briefer History of Time. Imagine someone travelling on a train bounces a ping-pong ball straight up and down, with one second in between bounces. To this person the ball hasn’t moved – it has a displacement of 0. To an observer beside the track, the two bounces would be 40m apart since that is the distance the train itself has travelled in between bounces. Both views are equally acceptable, and one should not be favoured over the other since both observers have the right to consider themselves at rest.

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  Relativity of Distance
• Secondly, the concept of there being no absolute standard of rest and therefore, no universal agreement on the speed of an object. Again, using the example from the book, we refer back to the ping pong ball. This time, the passenger on the train, hits the ball towards the front of the train with an observed speed of 10mph. To an observer on the track to ping pong ball is travelling at this 10mph relative to the train, plus the speed of the train relative to the platform. As with the theory of a lack of absolute space, both views are technically correct. Hawking poses the question; how do you define speed – relative to the train or relative to the Earth? With no absolute standard of rest, the ball cannot be assigned an absolute speed.

  

  Different Speeds

As a science and maths student, I am someone who likes a definitive answer (How far has the ball moved?! What speed is the ball moving at?!) and I consequently find myself both baffled and amazed by these ideas.

In conclusion, I found the book to give a really interesting and enjoyable introduction to the immense topic that is understanding our universe – so I would highly recommend it to those finding themselves curious to know more about this field. (There are loads more mind-boggling concepts like the ones above!)