Graduate Question on many world interpretation of Quantum Theory

[Sajid]

TL;DR

I argue that many-world interpretation can not be true.

Every second the universe branches into 5000 universes and each of those 5000 universes branches into 5000 more after one more second.
Now, consider an 80 year old person, he has lived close to 80*365*24*60*60 seconds, which is 2.5 Billion seconds. So, in his life time, universe has branched 5000^2522,880,000 times, which is unfathomably and incomprehensibly large number, maybe close to infinity if there is one.
Which means close to his death he has infinite many copies of him in different worlds

Now, if you choose randomly a person's existence, shouldn’t he/she find himself to be in that time where almost infinite copies of him exist, which is close to his death. So, every person should find himself/herself close to his/her final years with almost a probability 1We clearly see that is not the case, so many-world theory can not be true.

What is the flaw in this argument?

Would appreciate your comments/response. Thanks.

 

[PeroK]

The main flaw is that you don't understand MWI in the first place. Try reading:

https://www.preposterousuniverse.co...ion-of-quantum-mechanics-is-probably-correct/

 

[PeterDonis]

Every second the universe branches into 5000 universes and each of those 5000 universes branches into 5000 more after one more second.

Where are you getting these numbers from? Did you just make them up?

unfathomably and incomprehensibly large number, maybe close to infinity if there is one

There is no such thing as "close to infinity". Every finite number is the same "distance from infinity" as every other one.

if you choose randomly a person's existence

You can't. People don't get randomly assigned ages from 1 to 80 years. They each start at zero and age from there.

What is the flaw in this argument?

There are at least four: the three I mention above plus the one @PeroK mentioned.

 

[EPR]

Your main flaw is believing that in the MWI you can start your existence at the age of 80 out of nothing. Where have you seen aged people appear out of nowhere?

In theory, there are a near infinite number of universes where you are already dead(due to car crashes, brain strokes, Covid, etc) but that doesn't imply you are destined to die now because of the sheer number of worlds that get spawned.

 

[Klystron]

Suggest the OP read Hugh Everett and John Wheeler for a clearer understanding. Everett's biographer, Peter Bryne, also quite readable, places Everett in his proper Cold War setting in operations research while Everett's student, David Deutsch, explains wave mechanics in context.