Quote by Stephen Hawking
The radiation left over from the Big Bang is the same as that in your microwave oven but very much less powerful. It would heat your pizza only to minus 271.3*C - not much good for defrosting the pizza, let alone cooking it.
Summary
This quote highlights the concept of cosmic microwave background radiation, which is the residual heat from the Big Bang. The quote draws a comparison between this radiation and microwave ovens, stating that while they share the same type of radiation, the intensity of cosmic radiation is incredibly weak compared to a microwave oven. The quote humorously illustrates the point by mentioning that the cosmic radiation would only cool down a pizza to an extremely low temperature, rather than heating or cooking it.