Copenhagen breaks every physical symmetry we have
It doesn't, except in the minds of confused people assigning ontological significance to a calculational prescription. No interpretation out there has more predictive power than "1. Do unitary evolution, 2. Apply Born rule".
If you only consider it a calculational prescription and not an ontologically real thing, then you've totally just accepted MWI!
Today's post, Decoherence is Falsifiable and Testable was originally published on 07 May 2008. A summary (taken from the LW wiki):
Discuss the post here (rather than in the comments to the original post).
This post is part of the Rerunning the Sequences series, where we'll be going through Eliezer Yudkowsky's old posts in order so that people who are interested can (re-)read and discuss them. The previous post was Decoherence is Simple, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
Sequence reruns are a community-driven effort. You can participate by re-reading the sequence post, discussing it here, posting the next day's sequence reruns post, or summarizing forthcoming articles on the wiki. Go here for more details, or to have meta discussions about the Rerunning the Sequences series.