Lately in reading about modern physics and watching video interviews on contemporary cosmology, the number 10^100 (ten to the power of 100) kept coming up. Well, I found out probably why.

**Googol** (not Google) is a large number: “In decimal notation, it is written as the digit 1 followed by one hundred 0s.”

A

googolhas no special significance in mathematics. However,it is useful when comparing with other very large quantitiessuch as the number of subatomic particles in the visible universe or the number of hypothetical possibilities in a chess game. … To give a sense of how big a googol really is, the mass of an electron, just under 10^−30 kg, can be compared to the mass of the visible universe, estimated at between 10^50 and 10^60 kg. It is a ratio in the order of about 10^80 to 10^90, or only about one ten-billionth of a googol (0.00000001% of a googol).

Here’s the key reference: “The decay time for a supermassive **black hole** of roughly 1 galaxy-mass (10^11 solar masses) due to **Hawking radiation** is on the order of 10^100 years. Therefore, the **heat death of the universe** is lower-bounded to occur a googol years in the future.”

And then there’s the **googolpex**, an even larger number: “A **googolplex** is the number 10^googol, or equivalently, 10^(10^100). Written out in ordinary decimal notation, it is 1 followed by 10^100 zeroes, that is, a 1 followed by a googol of zeroes.”

One

googolis presumed to be greater than the number of atoms in theobservable universe, which has been estimated to be approximately 10^78. Thus, in the physical world, it is difficult to give examples of numbers that compare to the vastly greatergoogolplex. However, in analyzing quantum states andblack holes, physicist Don Page writes that “determining experimentally whether or not information is lost down black holes of solar mass … would require more than 10^(10^76.96) measurements to give a rough determination of the final density matrix after a black hole evaporates”. The end of the Universe viaBig Freezewithoutproton decayis expected to be around 10^(10^75) years into the future.

So, “physics says what?” — incomprehensible numbers, practically infinite times. Yikes!

See, for example, the “Closer To Truth” video interview “The Physics of Eternity.”