Why is the p-adic order of zero considered infinite?

  • Level: Undergrad 
  • Thread starter Thread starter DaTario
  • Start date Start date
  • Tags Tags
    Zero
Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
4 replies · 2K views
DaTario
Messages
1,097
Reaction score
46
TL;DR
Hi all, I would like to know why the p-adic order of zero, i.e., the exponent of the highest power of p (prime) that divides 0, is infinite.

best wishes
Hi All,
The p-adic order of a positive integer n is the exponent of the highest power of the prime p that divides n. I would like to know why it is commonly assumed that the p-adic order of zero is infinite.
best wishes,
DaTario
 
Last edited:
Mathematics news on Phys.org
The p-adic order and the p-adic absolute value are related by ##|x|_p=x^{-\operatorname{ord}(x)}##. Of course we want ##|0|_p=0##. The absolute value is the more important quantity.
 
Thank you, fresh 42. So it means that there is no connection with the purely "prime factorization of integers" meaning of the p-adic order. Is it correct?
 
Not really. Only the powers of a fixed prime are considered. However, it makes sense to define ##\operatorname{ord}(0)=\infty ## anyway: how often can we divide ##0## by ##p## until we get a remainder?
 
Thank you very much, you put a smile in my face with this very clear sentence. Thanks!