Exploring the Multiverse
For the third time in a week, I attended a one-day course at the City Lit in central London. The previous two courses were on Henry V [my blog posting here] and climate change [my blog posting here], but this latest course could not have been more different. Andrew McGettigan [his slides here] and Rich Cochrane [his slides here] spoke about the notion of the multiverse.
So, what exactly is the multiverse? The relevant Wikipedia page offers this definition:
The multiverse (or meta-universe) is the hypothetical set of infinite or finite possible universes (including the Universe we consistently experience) that together comprise everything that exists: the entirety of space, time, matter, and energy as well as the physical laws and constants that describe them. The various universes within the multiverse are sometimes called “parallel universes” or “alternate universes”.
Now I confess that I found the course a disappointment. I was looking for a scientific case for the notion of the multiverse, but we had very little actual science except the double-slit experiment (the relevance of which was not entirely clear). . Also I was hoping for an examination of how the notion has been used in culture – such as “His Dark Materials” trilogy – as a device to develop character and plot, but all we had was a suggestion that Sherlock Holmes actually exists in some universe out there.
I think the problem was that neither of the lecturers was a physicist or a writer; instead both have a background in philosophy and mathematics. I am highly sceptical about the whole notion of the multiverse: I don’t see how it helps us understand the mysteries of quantum mechanics; I don’t think there is any meaningful evidence to support it; I don’t think we have any tests to prove or disprove it; and playing with such concepts can be a slippery slope away from any meaningful sense of truth and reality.
But I could be wrong and, in another universe, another version of Roger Darlington could be laughing at me.
August 15th, 2015 at 9:42 am
Hello Roger
That’s a pity the course was disappointing. Howard says they should have had a physicist there.
As best I understand from Howard, there is a popular school of thought amongst physicists that the concept of multiple universes is not something that is brought in to explain quantum physics, but rather something that is already present in the fundamental mathematics of quantum mechanics.
It does seem to capture the public imagination. Howard was recently interviewed by “MTV” for his opinion on the “Berenstain Rift”:
http://www.mtv.com/news/2237774/berenstain-bears-alternate-universes/
August 15th, 2015 at 10:32 am
Gosh, I had never heard of the “Berenstain Rift”. I had to look it up:
http://www.bustle.com/articles/104398-berenstain-bears-conspiracy-theory-might-prove-that-parallel-universes-exist-or-that-were-all-just-terrible
Meanwhile I am as confused as ever. Is the notion of multiple universes, ‘simply’ a mathematical construct or does it have ‘real’ world implications?
August 16th, 2015 at 11:45 am
Apparently that depends on what you mean by “real world”! But basically, no, it doesn’t have such implications and we can leave it as something for quantum physicists to tinker with.
August 16th, 2015 at 11:56 am
Well, that’s a relief! We have enough other things to worry about.
August 22nd, 2015 at 4:57 pm
I saw a documentary a short while back by a famous US rock star. His farther, now deceased, had been the original proponent of this theory. He , the pop star, never wanted to go into science but as the years went on became interested in his fathers fame in this and other fields of physics. At first hardly anyone went along partly because the maths were complex. However gradually they started to be understood and verified. Now it seems most physicists concur and it is not merely popular but universally accepted. The famous Carl Sagan outlined the theory in his series Cosmos many years ago. If I remember correctly he endorsed it.
August 22nd, 2015 at 5:09 pm
It’s with googling Carl S and multiple universes to see a YouTube video. It starts: If you want to have a slice of apple pie you must fist invent the universe. Another video of his is about how many stars there are. Both videos are worth listening to if only to hear his voice once again. Regards
August 25th, 2015 at 10:05 pm
Hi, Phil.
I think that you are referring to Part 10 of the series “Cosmos” presented by Carl Sagan and I don’t think he endorses the notion of multiple universes in this series.
Also I don’t believe that “most physicists concur” with the idea or that the notion is “universally accepted”. I think the idea has many critics and is highly controversial.