Reaching out on the issue of friendship (1)
Robin Dunbar talks about the differences between people who are “larks”, using their phones mostly during the day, and “owls”, using them mainly at night, in a study of 30 students (6 March, p 36). The owls phoned more people frequently than larks did, but spent less time on the phone to each person.
Some years ago, a friend suggested that larks may be more introverted than owls 鈥� they find the activity of the day, which often requires them to be extroverted, tiring and will be ready for sleep earlier than owls, who gain energy through the day and are ready to stay awake and continue activity into the night. This is borne out by observation of friends and family.
If the larks noticed by Dunbar tended to talk for longer, but to a smaller number of friends than owls did, I wonder whether this fits with introverts having fewer friends.
Reaching out on the issue of friendship 92)
Your article on friendship brought a flashback to a science-oriented cruise of the Norwegian fjords that my wife and I took. One of the talks was by Dunbar, on the hierarchies of friendship groups.
He mentioned “Dunbar’s number”, the 150 or so people you know well enough not to be embarrassed to join uninvited for a drink if you run into them at a bar. I gained 15 pounds in my quest to verify Dunbar’s number.
Fukushima's real impact was in the evacuation
Regarding your look at the Fukushima nuclear power plant accident 10 years on, I wasn’t surprised by the small impact of radiation on life expectancy (13 March, p 18).
A 2011 study of survivors of the atomic bombings of Hiroshima and Nagasaki found that those who got an amount of radiation of less than 1 gray, a massive dose and many times that received by anyone living in the Fukushima area, . So why did those at Fukushima see life expectancy cut by three months?
The atom bomb survivors have been followed for decades and results from this . Those guidelines were ignored when Japan ordered a mass evacuation, including of sick and older people. , many people died because of those evacuations.
For me, time marches in one direction only (1)
Julian Barbour suggests that time may flow in two directions, highlighting that the physics of a billiard ball collision appears the same with time flowing forwards or backwards (6 March, p 46). That doesn’t work if the event is seen as a whole: balls would jump out of pockets and self-assemble in the centre of the table, violating Newton’s laws.
Surely causality is the indicator of time’s direction, and an argument against universes with reversed time.
For me, time marches in one direction only (2)
Perhaps at the big bang, time did move backwards and forwards. Our universe moved forwards and the antiverse, with antimatter, moved backwards.
This would explain a flaw in the big bang theory over what happened to the antimatter, which should have appeared in equal amounts to matter.
Antimatter may experience antitime and antigravity, so in our universe it would fall up. However, if we study antimatter in our universe, it may seem to fall, but is actually rising, only in reverse time.
Have we found the solution to space junk?
The article on the laser thruster to power satellites was fascinating, and got me thinking about another application (13 March, p 12). Would it be possible to use the same principle to deorbit defunct satellites or push space junk into lower orbits so it burns up in the atmosphere?
Big spending may lead to even bigger corruption
Rowan Hooper’s plan to eradicate world poverty by spending $1 trillion doesn’t mention corruption, which is said to waste far more than $1 trillion per year (27 February, p 38).
Well-overseen pilot projects, like those he cites, may not scale up to well-overseen megaprojects. Do we simply assume that corruption will be obliterated by the flood of money? Rather, I would expect corruption to scale up: the sweeter the pot, the more grasping hands.
Childhood mental health has long been in decline
Your report on the impact of the pandemic on children’s health is all well and good, but we need an investigation into why we have seen a big spike in mental illness in the past few decades (6 March, p 8).
The recent mental health decline seems attributable to the lockdown conditions affecting everyone, yet your figures make it clear the pandemic wasn’t the cause of the decline, but the latest factor contributing to it.
I have a plethora of ideas as to why young people might be experiencing pathological levels of distress given the rapid deterioration of the planet and relentless evolution of social dynamics perpetuated by the online world. However, I am curious whether my assumptions are correct or if this decline is related to factors that I haven’t considered.
There is a good side to slugs and flies
In recent weeks on your pages, we have learned how to deal with or even kill both slugs and flies (27 February, p 49).
Perhaps it is time to give their side of the story. Most of the 40 or so species of slug are active recyclers/composters in the garden, with similar positive roles for the thousands of flies. Most of these animals do no harm, yet we kill many of them because of the few species that are generally no worse than minor irritants.
More than one way to crack interstellar travel
The idea of a slower-than-light warp drive is interesting (6 March, p 16). But I wonder if any civilisation with the resources necessary to fabricate a spaceship’s shell compressed from something that was Earth’s mass, and then accelerate it, would find it easier to achieve time dilation by the still complex, but slightly more practical, method of a low-mass vessel propelled as close as possible to the speed of light?