10 TWO NEW WORLDS 



approximately 10,000 trillions to 1. This ratio 

 appears to be of fundamental importance. It is 

 nothing less than the ratio of the scales of successive 

 universes. 



Since in the minute world we are now exploring 

 atoms correspond to suns, and electrons to planets, 

 we may boldly equate our earth to an electron, 

 and find how far the analogy holds good. 



Time and space are, after all, purely relative. If, 

 at midnight to-night, all things, including ourselves 

 and our measuring instruments, were reduced in 

 size 1000 times, we should be left quite unaware 

 of any such change. There would be nothing to 

 prove that it had taken place. Also, if all events 

 and all timepieces were accelerated in the same 

 ratio, we should be equally ignorant of the event. 

 We measure size by our own bodies or by the size 

 of the earth. We measure time by the rotation of 

 the earth or by its revolution round the sun. 



Now, if we were small enough to live on an 

 electron as we now do on the earth, we should 

 measure all things by comparing them with our- 

 selves or with our electron, and we should measure 

 time by the rotation of our electron or its revolution 

 round the central atom. Now, the period of the 

 earth's revolution about the sun is 3 x 10 7 seconds 

 (= one year), whereas the period of revolution of 

 the average electron round its atom is 2xlO~ 15 

 seconds. The ratio of these two periods is 1-5 x 10 22 , 



