Trolley dilemma: Will you use one to save the planet?
Recent correspondence has focused on transport options, such as encouraging more walking, free local buses and so on, as ways to cut car use. To this end, I would like to propose that every UK household is given a shopping trolley (Letters, 30 December 2023).
My trolley has been a companion since 1991, bought in Paris where everyone had one. Aside from carrying store goods and saving on backache from lugging heavy bags, it has also transported compost and plants from the garden centre, tiles from the local store, rubbish to the recycling dump and parcels to and from collection points. Despite a wobble, it remains stylishly French and supremely useful.
AIs may develop a language of their own
Philip Seargeant discusses the implications of artificial intelligence making it easier to communicate by bridging the gap between speakers of various languages. However, AI might create its own language to communicate with other AIs all over the world and humans won’t be able to understand what they are talking about (30 December 2023, p 19).
Mesoamericans perfected this food-bridging recipe
Stuart Farrimond, in his look at the science of “food bridging”, seems to have rediscovered the classic , also familiar as the variant The peanut bridging ingredient originated in Central America before becoming more widely known (16/23 December 2023, p 70).
Proof of cosmic life may be lurking in your kitchen
The survivability of bacteria under extreme conditions, as highlighted in “What’s living in your kitchen?”, surely gives support to the theory of panspermia. This proposes that life such as bacteria may travel the universe via a suitable object and seed hospitable planets (16/23 December 2023, p 64).
Perhaps bacteria can’t survive in a vacuum, but could be trapped within meteors or comets for millennia or even millions of years. Detection of exotic bacteria in rocks from space would offer the simplest proof that life is widespread in the universe.
A ready source of wrecks to protect marine parks
You note that shipwrecks not only provide refuges for fish, but foil bottom trawling. A good place to put wrecks would be in protected marine reserves. A good source of wrecks would be boats caught fishing in such reserves (9 December 2023, p 13).
Planets' lucky escapes may have simpler explanation
Regarding detection of planets that seem to have survived the death of their star, there seems to be an assumption that a planet in orbit close to a white dwarf was always in that orbit (16/23 December 2023, p 60).
Consider a planet that was far out prior to star death. When the dying star ends its red giant phase, shrinking back to form a white dwarf, friction with the ejected stellar nebula could slow the planet, causing it to very slowly spiral inwards. Outer planets could also have their orbits disrupted by close approaches of other stars or other planets. Collisions with moons could do the same.
Energy efficiency gains can have downsides
Doubling energy efficiency is a headline target from COP28, but is this a win for the planet or for the fossil fuel industry? If not coupled to reductions in fossil fuel production, rebound effects can diminish the emissions reductions that we would expect (9 December 2023, p 8).
Energy efficiency can even boost overall energy consumption (via an effect known as Jevon’s paradox) if, for example, financial savings are reinvested in expansion of carbon-intensive industry. The primary value of improving efficiency is in making a fossil fuel phase-out more practicable. The phase-out is, inconveniently, essential.
100 trillion synapses can't be wrong
The saying about the brain being the most complex known structure in the universe is usually stated in relation to its structure, connectivity and circuitry 鈥� the connectome (Letters, 16/23 December 2023).
Consider this: a human brain has about 100 billion neurons. Protuberances from a neuron make many connections with other neurons. The intricate structure gives rise to an estimated 100 trillion connections in the brain. With 100 billion neurons making 100 trillion connections, the human brain is truly complex.
Let's turn the tables on Western collapse
Peter Turchin’s studies of social collapse may have relevance to the objectives and means of Russia and other states to enhance the collapse of some Western societies (9 December 2023, p 36). Can’t the West use history to expedite the fall of dangerous authoritarian regimes?
Would a robot world have a biosignature?
In searching for extraterrestrial life, we need to think about what we mean by life. It could be organic, based on carbon, hydrogen, oxygen, nitrogen, phosphorus and sulphur. Or it could be completely different (25 November 2023, p 40). For example, we can imagine machines becoming a second form of life on Earth, capable of Darwinian evolution. How would we detect a planet populated by machines or by organisms using a different chemistry?
Got that shrinking feeling about BMI
Has anyone taken the following into account in describing a “healthy BMI” for older people? We all lose height as we get older, through vertebral body collapse and loss of hydration of the intervertebral discs. Hence, even if our weight stays the same, our BMI will gradually creep up (2 December 2023, p 12).