Tag Archives: time

One just raced past and I have only about 1000 left!

Photograph of the tower on the summit of Moel FamauA week has just raced past and it’s time to write a blog post – the 479th.  The first twenty or so posts were published randomly when I thought of something to write.  Only the last 457 have been published regularly on Wednesdays.  However, given the average life expectancy of a male in Britain is 4225 weeks, that implies I have been writing a weekly post for slightly more than a tenth of my life expectancy.  More depressing, considering the speed at which weeks are racing past me, is that I probably only have about 1000 weeks left.  A thousand is a big number if you are trying to count sheep to get to sleep but quite a small number when thinking about the life of the universe [see ‘Will it all be over soon?‘ on February 2nd, 2016].  I have mixed feelings about my perception of a thousand weeks of life remaining.  It seems short enough to make me pause, think about slowing down so that the weeks do not fly past so quickly and to write about it.  But it is probably not short enough to induce me to make dramatic changes to my lifestyle.  Perhaps the most likely effect will be to increase my awareness of the need to make time for the important things in work and life.  At work that probably means being more focussed on the big picture while in life it suggests focussing on the atelic activities, i.e. those pursued for their own sake, such as our weekly walk up Moel Famau.

Source: Mia Levitin, Hacking the life hack, FT Weekend, 21/22 August 2021.

Trees are amongst the slowest moving beings with which we share our world

Last month I mentioned that I started reading ‘Overstory’ by Richard Powers on my trip back from the US [see ‘When an upgrading is downgrading‘ on August 21st, 2019].  I only finished it about ten days ago because I have not had much time to read and it is a long book at 629 pages.  It is a well-written book including some quotable passages, but one that I particularly liked which seems relevant in this era of polarised perspectives: ‘The best arguments in the world won’t change a person’s mind.  The only thing that can is a good story.’  And, Richard Powers tells a good story about the destruction of the ecosystem, on which we are dependent, as a result of large-scale felling of ancient forests.  The emphasis should be on ‘ancient’ because time for trees appears to run at a different speed than for humans.  While we can observe the seasonal changes in an ancient woodland, we are barely conscious on the growth and movement of the woodland.  When we read Shakespeare’s lines in Macbeth about ‘Great Birnam wood to high Dunsinane Hill shall come’,  we think of it moving over the landscape at the speed of an army of people, whereas woods move so slowly that we do not live long enough to notice the change.  For instance, there is a spruce tree in Sweden that is 9,500 years old.  Our spatial understanding of a tree also leads to a misconception because we can only see the overstory, i.e. what is happening above ground; so, we think that each trunk is an individual tree, whereas for many types of tree many apparently individual trunks belong to the same organism with an extensive understory below ground which might be thousands of years old.  All trees are involved in a substantial understory communicating with each other in ways that we can barely imagine let alone comprehend.  Most of the ancient forests in Europe were cut down before science revealed the scale and complexity of life in them; yet, we still continue to fell forests as if there was an inexhaustible supply rather than one that could take as long to replicate as humans have been recording our history.

If you would like to arguments about trees then read ‘The Hidden Life of Trees’ by Paul Wohlleben, London: William Collins, 2017 (my title is a quote from this book).  If you are unconvinced then read the ‘Overstory’ by Richard Powers, London: Penguin (Vintage), 2019.

We inhabit time as fish live in water

A couple of weeks ago (‘Only the name of the airport changes’ on June 12th, 2019) I wrote about the stretching and compression of time while I waited for my much delayed flight to Reno. I mentioned Aristotle’s view of time as the measurement of change; however, Newton believed that time passes even when nothing changes. Einstein resolved the conundrum, represented by these different views, using the concept of a space-time domain forming a gravitational field containing waves. My title is a quote from Carlo Rovelli’s book, ‘The Order of Time‘. And, according to Rovelli, ‘mass slows down time around itself’, which I think will cause waves in the space-time domain .  Conservation of energy implies that the movement of an object will tend towards space where time passes more slowly, i.e. in the vicinity of large masses. Hence, things fall downwards because time runs more slowly close to the Earth. This implies that time passes more slowly at the airport than on the plane in flight; but, of course, the differences are too small for us to measure or perceive.

Image: Art work ‘Gaia’ by Luke Jerram in Liverpool Cathedral


Carlo Rovelli, The Order of Time, Penguin, 2019.

Only the name of the airport changes

The conference that I attended last week was in Reno, Nevada and, on my way to it, I stopped over in Dayton, Ohio and visited the US Air Force Research Laboratory to present the results from our research project supported by their European Office of Aerospace Research & Development (EOARD).  The journey from Liverpool to Dayton, via Manchester and Altanta airports, took 17 hours; however, that was short compared to the journey from Dayton to Reno, via Chicago and San Francisco airports, which took 24 hours door-to-door or rather hotel-to-hotel.  ‘Only the name of the airport changes’ is a quote from Italo Calvino describing the city of Trude in his book ‘Invisible Cities‘; but it also described how I felt looking out from my window seats at successive airports over the four days that I travelled from Liverpool to Reno.

We arrived at Dayton airport at 5am for a 7am flight to be told that it was cancelled and we were re-booked on a flight leaving at 5.18pm.  We tried to re-rent the rental car that we had just returned but were told every car was booked; so, we were stuck in Dayton airport for 12 hours.  Your perspective of time changes in these circumstances.  At 5am with nothing much to do, 12 hours seemed like infinity; but at 5pm when we were about to board our flight, the same 12 hours seemed short – almost as if we had only arrived at the airport an hour or so earlier.  Augustine observed that our consciousness is based on memory and anticipation such that time is entirely present in our minds as memory and as anticipation.  While Aristotle considered time to be the measurement of change.  Hence, since I was anticipating no change during my 12 hours of waiting, my perception of time was of it passing very slowly.  Whereas, when I was boarding my flight 12 hours later, my memory was of having done the same things that I would usually have done while waiting for a flight [reading and editing draft manuscripts from my research group]; and hence my perception of the elapsed 12 hours was compressed into the usual 2-hour period spent at an airport prior to a flight.  The apparent unchanging view out of the plane’s window, both in flight and, to a lesser extent, on the ground also tended to distort my perception of the passage of time.


Italo Calvino, Invisible Cities, Penguin Vintage Classics, 1997.

Carlo Rovelli, The Order of Time, Penguin, 2019.