Interrompemos a programação actual para conversas por e-mail subsequentes a conversas a hora de almoço versando sobre probabilidade de ganhar o euro-m

Well, yeah... judgement day is near, there could be black holes all around us! :D

Then there are other nice things - stranglets, magnetic monopoles and the vacuum instability that we can worry about as well ;)

From: Daniel Filipe Rocha Da Cunha Rodrigues
Sent: 16 April 2008 11:00
To: Roderik Bruce
Subject: RE: So,
It is true. Well, tough luck the probability couldn’t state something impressive with regard to the lottery.

Actually, I just realized something. What if, assuming they are created by this collision process, and knowing it would take thousands of years to grow there’s already a black hole on going somewhere on the earth? It is possible we haven’t even realized it ;-)


From: Roderik Bruce
Sent: 16 April 2008 09:57
To: Daniel Filipe Rocha Da Cunha Rodrigues
Subject: RE: So,

:)
yes, the calculation is correct - if the probability of winning the lottery is what you say, the probability of winning it 3 times in a row is 2*10^-24, which is even less. However, remember that the 10^-22 is the UPPER LIMIT of the probability of something bad happening, this probability might very well be zero.

This number 10^22 is actually valid mainly for magnetic monopoles and vacuum instabilities (other "bad things" that people worry about with the LHC that they think could destroy the earth). The story with the black holes is actualy even more complicated - most cosmic ray collisions have a very large momentum in the earth's reference system, meaning that any black hole created in these should conserve the momentum and would probably traverse the earth without interacting since they are so tiny. So for the black holes you need to consider head-on cosmic ray collisions. However, when you take into account also the number of other planets, stars etc which are still there and not swallowed by black holes you can probably get some impressive statistics as well.

Roderik