Nth world problems
In Rowan Hooper’s article on the multiverse, physicist Seth Lloyd is quoted pondering the notion that multiple worlds are actually out there somewhere, but we cannot access them (27 September, p 32).
Later, Hooper describes the double-slit experiment, in which a photon appears to act like a wave, diffracting at both slits and creating an interference pattern. Hooper says that according to the many-worlds interpretation, the interference pattern comes about when a photon interacts with its clone passing through the other slit in a parallel universe.
This suggests that photons belonging to different universes do interact, therefore we can access other universes.
London, UK
Nth world problems
Seth Lloyd offered Don Page $1 million to play quantum Russian roulette, where each pull of the trigger divides the universe into a version where the gun fired and another where it did not. Page declined because he didn’t like the thought of his wife’s distress in the worlds where he died.
But he was too late. Declining to play was a choice which therefore caused the universe to split; so he both declined and chose to play. He could only avoid his wife’s distress if Lloyd hadn’t offered him the choice in the first place.
Whittlesey, Cambridgeshire, UK
Nth world problems
Seth Lloyd enjoys the “marginalisation of humanity” wrought by the endless repeated worlds in the multiverse.
But the theory also implies each individual becomes infinitely extended in space and time by the ever-multiplying copies of their former selves. Is this ultimate human marginalisation? Or collective elevation to effective godhood? Each to their own!
Warley, West Midlands, UK
Predictable brains
Dan Jones reports that people who are told voting patterns can be predicted by measuring brain activity still believe the subject’s decisions are based in free will (27 September, p 11).
We could get the same result without the fancy technology by giving someone a thorough personality test that will also predict their decisions with very high accuracy. That is because our “free will” decisions now are based on our past experience.
So I can quite happily believe I am making decisions based on free will, even though my wife can predict those decisions with 100 per cent accuracy based on over 40 years of observation.
West Launceston, Tasmania, Australia
Predictable brains
If determinism precludes any real decision-making, then does it also preclude the spawning of new multiverses?
Bournemouth, UK
Women warriors
Rosemary Bryant Mariner makes a compelling argument to place women on an equal footing with men in military combat roles (20 September, p 26). In a nutshell, this enables everybody to participate in armed conflict.
But I would prefer to look at a change in the status quo from the other end of the spectrum: we should strive to get men on an equal footing with women so that neither can participate in war.
The horror of war seldom, if ever, resolves conflict permanently; a negotiated peace inevitably follows the killing.
Thus I would prefer to read an article about the justification for getting more women into roles where they are able to utilise their talents to prevent political arguments progressing into all out warfare.
Jeddah, Saudi Arabia
Porpoiseful rejection
In her article exploring whether dolphins live up to their reputation for intelligence, Caroline Williams tells of being forcefully rebuffed by a dolphin after attempting to connect with it (27 September, p 46).
In this era of climate change, the possibility that dolphins don’t want to be friends with humans makes them seem more intelligent and emotionally developed than ever.
Hampton, Middlesex, UK
Unpicking the globe
I read Debora MacKenzie’s article on the decline of the nation state with great interest, having arrived at similar conclusions in 1990 (6 September, p 30).
At that time I came across chaos theory, which made it clear to me that the complex system we call community is better governed from the bottom up than directed into preconceived outcomes by the top-down state.
State management lacks the vital feedback loops that connect us in the joined-up world, and replaces them with fixed legislation that is resistant to any kind of evolutionary change.
Thinking that scientists would be unlikely to apply this new science to human affairs led me to write a book on the subject, The State is Out of Date: We can do it better.
The complex factors that determine the relative value of apples to tennis balls or smartphones to refrigerators aren’t derived by the existence of a global financial system and nation states.
Should that system collapse it is quite possible that community and commerce would soon figure out a superior and sustainable means to carry on business, not quite as usual, and perhaps better.
London, UK
Knit one, Perl one
I was interested to read about a computer-controlled loom that can create 3D fabrics (27 September, p 21).
That is certainly an innovation. However, there is another, more established, way of creating 3D fabrics. It’s called knitting.
Sanderstead, Surrey, UK
Computer whizz-ard
I can’t quite agree with Tim Stevenson’s rejection of magic in technology (27 September, p 31).
I’m glad to say computing is still both my job and my hobby after more than 40 years in the industry. The fact that there is always something new to learn is a source of continual magic to me, and, I suspect, many of my colleagues.
I still remember punch cards and magnetic core memory, and I have only recently been given to understand that IBM is not an acronym for “I Believe in Magic”.
Romsey, Hampshire, UK
Universal cry baby
I had an experience which supports the idea reported by Bob Holmes that baby mammals share the same distress cry (20 September, p 14).
When our firstborn was 5 months old, my husband and I decided to have a day out on the hills, and we climbed Ben Lomond in the Scottish Highlands.
On the way down, the wee one started to cry. I assumed he was hungry, but since it was February and getting dark, we thought it better to get off the hill than to stop and feed him.
As my husband, who was carrying the baby, set off ahead, I noticed that the ewes on the hillside were moving towards us, calling as they streamed across. On reaching the area we were in, they searched around for the “lost lamb”. While these ewes were pregnant, it was too early for there to be any lambs on the hillside. I am convinced they responded to our son’s cries.
Marybank, Ross-Shire, UK