
130 Questioning the Universe: Concepts in Physics
12.5.3 THE LORENTZ CONTRACTION
This was certainly a great surprise. Physicists at the time could not understand this
strange result in terms of any known physics. When such a situation arises, new
ideas, not based on already known physics principles, are introduced. This can lead
to new theories, which result in an entire revolution in our thinking or a speci c
and limited idea to explain a particular experimental result. These ideas are usually
known as ad hoc. In Chapter 9, we discussed Bohr’s ad hoc assumptions about the
atom. Ad hoc ideas or assumptions have been quite useful throughout the ...