How an argument with Hawking suggested the Universe is a hologram
arstechnica.com
arstechnica.com
I was surprised and happy to read this part. With my multiple attempts (and mostly failing) to understand quantum mechanics or string theory, I got the impression that this topic is never approached, and that omission never explained. If you're going to try to convince someone that our universe has multiple parallel futures, you should be ready to explain how that relates to our lives.
I think that's what lead me to the impression - as an outsider - that fascinating sounding things like the many-worlds interpretation are beautiful ideas that do not exist outside of equations, they're a kind of science fiction, a kind that is backed by mathematics and published in journals.
Much of the 'far off' musings in the many worlds interpretation is the result of physicists being bored and wanting to have some fun, or some popsci gone horribly wrong.
Edit: Also, if we did live in a holographic universe, there may be experimental proof of it (the ars article left it out). Ironically linking to a popsci article... (says that we probably aren't)
link: http://news.discovery.com/space/we-might-not-live-in-a-holog...
MWI requires you believe that physics is governed by the Schroedinger wave equation. Copenhagen requires you to believe that the Universe is governed by the Schroedinger wave equation, but only when we're not looking at it, and when we look at it reverts back to the classical world through some mechanism so far unexplained, and this collapse of the quantum world into the classical world somehow produces no testable predictions that would distinguish it from what we would expect the system to look like if the wave equation just kept on working.
In other words, the MWI is what QM predicts if you assert that the observer is described by QM. So either we assert that there is some complex "collapse" mechanism which is somehow tied to observation, or we're stuck with MWI. Thus Occam's Razor says that, unless we have evidence for a complex "collapse" mechanism (hint: we don't), we should accept the MWI.
Unfortunately Everett did his work after most physicists had become comfortable with "shut up and calculate". And therefore they did not want to bother thinking about it seriously. Of the people who did think about it, many were wedded to other interpretations, and so were not inclined to accept a weird upstart.
However it is worth noting that a survey of cosmologists some years ago found that over 50% accepted the MWI. When you get away from the philosophical fringe, there is simply no other interpretation of QM whose reasoning is half as compelling as the MWI.
There are two driving forces in science: the skepticism of grad students and the mortality of professors.
I suppose that at least turns it into a psychological rather than physical mystery, but still a vexing one.
Isn't it a bit presumptuous to demand that any theoretical truth about the nature of the entire universe should be relatable to the life of a human?
If it were the case that there are multiple parallel futures, then we ask ourselves:
How do I navigate myself to the best-possible future for me and those who surround me?
It is your very actions day by day that determine where it is that you go.
Sure, but that doesn’t mean that humans are able to understand nature in a way that relates to them, at least not on all levels. We weren’t built for large and small scales, our brain is only intuitively familiar with human scales. A second to a century. One millimeter to 100 kilometer. A few centimeters per day to a few dozen kilometers per hour.
I don’t think intuitiveness should be a deciding factor when it comes to describing nature.
I guess all of the work in physics, chemistry and other sciences of the past thousands years was all in delusion?
Nothing was learned, nothing.
It looks like humans are very capable of understanding non-human-scale nature, just not intuitively.
Think about the implications of a real MWI. Real universes are not cheap, an apparently infinite supply is extremely ridiculous.
2. The "universes" that appear in MWI are simply parts into which the universal wavefunction gets decomposed. Getting rid of them would require some sort of wavefunction-pruning process. You might equally say "Destroying universes is not cheap", a statement for which I think I have every bit as much evidence as you have for yours.
(Of course non-MW interpretations of QM do have a wavefunction-pruning process. They don't generally have much to say about how it happens, and they tend to require ridiculous things like building the notion of "observer" into the fundamental equations of physics. Or, as in the case of Bohmian QM, they include all the same mechanics as MWI plus a bit extra and then claim to be more parsimonious simply because they attach the label "real" to a different subset of what the theory talks about.)
Real branches are not cheap, an apparently infinite supply is extremely ridiculous.
:-)
Of course, when that started, the garment caught on fire.
The essay you linked to is Deepak Chopra-style quanto-babble with little content that can actually be translated into something meaningful in the real world. Indeed, one must ask the question, if "reductionist" scientists are so fundamentally wrong about everything, then how come they can so successfully predict so much? Is there some physical experiment that can be run that this will produce better predictions for?
So, I'd say the relationship is that Hawking et al are doing science, and Talbot is using their work as the seed for his internal random number generator.
I hope this is an exaggerated anecdote and not actually the case.