Quite normally these days, headlines deliberately mislead – it’s called click-bait – and so often these days “Multiverse” is that click-bait. Total bollox, but it sells clicks.
Trouble is, when it’s the headline, it’s very hard to tell if the piece itself is saying anything useful that may or may not depend on any multiverse ideas. The simplest conception that there are parallel universes where alternate realities have arisen independently of our own is not – and never can be – science. It’s a thought experiment. And as a theory it can explain nothing – by explaining everything conceivable as merely a possibility, it explains nothing. And being an independent universe can never involve any empirical validation in this one. Just not science.
There are scientific theories that predict multiple “universes” that become independent, but they must share some historical points with ours. Even these – the wrong side of some space-time horizon – will only ever be empirically testable by very indirect means, if ever. However, their explanation can have value, and these can explain – must include explanation of – different situations arising non-randomly in these different zones. A single multiverse: one universe, multiple zones, not multiple universes.
Philip Ball writing in Prospect asks “Just how special is human existence?” and his headline writer baits the hook with “The answer could lie in multiverse theory.” Yeah right. Actually some interesting discussion of anthropic prespectives of our special human existence. How could there be any other?
Jim Baggott responds also in Prospect “The problem with “multiverse theories”: they’re just not science.” Agreed. And as he notes, the context of what the author is actually trying to say matters more than any misleading headline.
Anthropic discussions remain interesting however. Also recently, here Max Tegmark writing in Cosmos on the Fermi Paradox paper by Anders Sandberg et al that has been shared widely. (Interesting doesn’t mean either Sandberg or Tegmark are necessarily right …. that’s a longer story eh, Rick?)
Science. The original “fake news”. Sigh!
[Post Note. Talking of science news, New Scientist now has this story:
A cosmological story that explains how multiple independent universes came into being from earlier universe(s) can be science (and is likely true). Anything else is a thought experiment I say, not science. https://t.co/B0kYl6jvsF
— Ian Glendinning (@psybertron) June 28, 2018
Which on the face of it is addressing the bollox, at least making the important distinction between cosmological space-time history and non-scientific quantum hackery.]
[Post Note: Twitter exchange with Tom Chivers, referred to by Elizabeth Oldfield in sharing the original link (follow the thread too, for alternative statements of the argument consolidated below).
— Elizabeth Oldfield (@TheosElizabeth) June 25, 2018
“Not science” is only interesting in so far as scientific journals and supporters of scientific explanations make claims for a scientific monopoly on justifying what are really metaphysical assertions.
What really matters are “good explanations” – explanations that are (a) likely to be true, (b) not super-natural and (c) likely to be useful in their explanatory reach. Honesty helps too, when it comes to metaphysical positions.
Likelihood is about information complexity – kinda like Occam’s simplicity argument, which sparked the original exchange – but really about probabilities of events in space-time. Evolution – simple algorithmic repetition – is the simplest, indeed inevitable, path to complex life and intelligence. (The reason other non-human life is unlikely to exist in the “observable” universe is because we’ve failed to observe it, despite our efforts. Not that it is unlikely to arise. We have, already. The observable matters here – see also “horizons”.)
It’s a necessity that everyone’s world-view / metaphysics has a “position” (mode-of-being / personality) OK. Even self-proclaimed atheist / scientist types. But need you call it “God” if you don’t also ascribe supernatural causal powers to it?
— Ian Glendinning (@psybertron) June 25, 2018
JBP reminds us that even the most objective scientists need metaphysical positions.]
[Post Note – Aug 2018 and the Multiverse-Bollox click-bait continues. One Universe is Not Enough. Ethan Siegel this time from It Started With A Bang writing in Forbes. (Hat tip to Rick Ryals on FB for the link.)
As I said “This is just a word-game – publisher’s click-bait – of undermining the word universe. Cosmology isn’t science, isn’t physics. Starting with the definition that there is only one, with nothing beyond it in space or time – the Uni-verse we’re talking about – there are simply zones separated by horizons, Horizons that limit how much known “laws and constants” of physics communicate and change across such horizons. The universe is more than the observability from the zone we’re in. It’s a communication problem, with meta-laws – all other “laws and constants” evolve as they are repeatedly communicated. (I’m with Verlinde and Rovelli)“]