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<<|
----
My latest posts can be
found here:
  * ColinsBlog
----
Previous blog posts:
  * ParallelogramPuzzle
  * BackOfTheEnvelopeCOVID19
  * APointAgainstTheAxiomOfChoice
  * InDefenseOfTheAxiomOfChoice
  * JourneyingHomeThroughStormDennis
  * EarthRadiusRefined
  * VolumeOfASphere
  * BigOhAndRelations
  * MathematicalRelations
  * IntroducingBigOh
  * ConstantDifferences
  * AlgorithmsAndSizesOfInstances
  * IntroducingTimeComplexity
  * TheLinearFrog
  * SeventyVersusOneHundredRevisited
  * HowTheFarragoWorks
  * SeventyVersusOneHundred
  * PowersOfTwoInLexOrder
  * EmergingEExpanded
  * RageInducingSystemImplementation
  * TheBookIsNotAlwaysRight
  * EmergingE
  * ImpossibleToTranslate
  * WaitingInVain
  * NonRepeatingDecimals
  * RationalRepeats
  * WhyIsItLovely
  * CompilingCryptoConnections
  * ExploringConnectionsBetweenCryptoSystems
  * ElwynBerlekampHasLeftUs
  * RootCauseAnalysisAndThePhotocopierQuestion
  * TheUpDownTides
  * TheForeAftTide
  * TheSidewaysTide
  * WrappingUpWrappingUpTheEarth
  * TheOtherWrappingTheEarthProblem
  * WrappingTheEarth
  * TheRingOfSteel
  * RoundingUpTheRopes
  * OtherOtherOtherRopeAroundTheEarth
  * RopeAroundTheEarthRefined
  * TheOtherRopeAroundTheEarth
  * ElementaryEstimates
  * LatitudeCorrection
  * JustGiveMeTheAnswer
  * MoreMusingOnPollardRho
  * IdleThoughtsAboutPollardRho
  * WhenOptimisingCodeMeasure
  * ADogCalledMixture
  * AnotherPayPalScam
  * WhyTopPostingHasWon
  * UnexpectedInteractionOfFeatures
  * ArchimedesHatBoxTheorem
  * ConsideringASphere
  * ToLinkOrNotToLink
  * GenericAdviceForWritingAThesis
  * JustTeachMyChildTheMaths
  * NotASpectatorSport
  * LeftTruncatablePrime
  * TheDoctorAndTheLawyer
  * FourPointsTwoDistancesProof
  * MeetingRonGraham
  * NapkinRingVersusSphericalCap
  * TheFourPointsPuzzle
  * RadiusOfTheEarthPartTwo
  * GrepTimingAnomaly
  * TheRadiusOfTheEarth
  * ThisWorksToCureMyHiccoughs
  * PerhapsWeSavedOne
  * ThinkingAboutMastodon
  * DisappearingTrainsOnVirgin
  * TheIndependenceGame
  * OneOfMyFavouritePuzzles
  * ThinkingAboutRecursion
  * MemorisingTheTube
  * SpikeySpheres
  * SurprisinglyQuick
  * AnUnexpectedFraction
  * YouHaveToAdmireTheirOptimism
  * RepresentativesMatter
  * PythagorasByIncircle
  * APuzzleAboutPuzzles
  * HowNotToDoTwitter
  * Calculating52FactorialByHand
  * SmallThingsMightNotBeSoSmall
  * NotIfYouHurry
  * FactoringViaGraphThreeColouring
  * AnotherProofOfTheDoodleTheorem
  * WhenObviousIsNotObvious
  * GraphThreeColouring
  * TheDoodleTheorem
  * BeCarefulWhatYouSay
  * TheMutilatedChessboardRevisited
  * AMirrorCopied
  * TheOtherOtherRopeAroundTheEarth
  * PhotocopyAMirror
  * ThePointOfTheBanachTarskiTheorem
  * SieveOfEratosthenesInPython
  * FastPerrinTest
  * RussianPeasantMultiplication
  * FindingPerrinPseudoPrimes_Part2
  * FindingPerrinPseudoPrimes_Part1
  * TheUnwiseUpdate
  * MilesPerGallon
  * TrackingAnItemOnHackerNews
  * HackerNewsUserAges
  * PokingTheDustyCorners
  * ThereIsNoTimeForThis
  * PublicallySharingLinks
  * LearningTimesTables
  * GracefulDegradation
  * DiagrammingMathsTopics
  * OnTheRack
  * SquareRootByLongDivision
  * BeyondTheBoundary
  * FillInTheGaps
  * SoftwareChecklist
  * NASASpaceCrews
  * TheBirthdayParadox
  * TheTrapeziumConundrum
  * RevisitingTheAnt
  * TheAntAndTheRubberBand
  * IrrationalsExist
  * MultipleChoiceProbabilityPuzzle
  * RandomEratosthenes
  * WrappingUpSquareDissection
  * DissectingASquarePart2
  * DissectingACircle
  * DissectingASquare
  * AnOddityInTennis
  * DecisionTreeForTennis
  * DecisionTreesInGames
  * AMatterOfConvention
  * DoYouNourishOrTarnish
  * BinarySearchReconsidered
  * TwoEqualsFour
  * TheLostPropertyOffice
  * TheForgivingUserInterface
  * SettingUpRSS
  * WithdrawingFromHackerNews
----
Additionally, some earlier writings:
  * RandomWritings.
  * ColinsBlog2010
  * ColinsBlog2009
  * ColinsBlog2008
  * ColinsBlog2007
  * ColinsBlogBefore2007
********
During this time of lockdown and/or self-isolation, it's
tempting for those of us content with our own company to
sit tight indoors and wait it out.  But I'm reminding of
some stories told to me by my friend Laurie Brokenshire.

[[[>50
Laurie was a genuinely fascinating man. Humble and modest,
he had a degree in maths, an OBE, had swum the channel, was
a member of The Magic Circle, had been a submariner, and had
been Commodore of HMS Raleigh. He was also regarded as the
world's best solver of mechanical puzzles (yes, really),
and had a collection of over 50 thousand of them.

He and his wife fostered over 80 children.

There's more, but that's enough to give you an idea, and
you can read more on his Wikipedia page:

''' <ul><li>
''' <a href="https://en.wikipedia.org/wiki/Laurie_Brokenshire">
Laurie's Wikipedia page
''' </a></li></ul>
]]]
My wife Rachel and I were staying with Laurie, and during
conversation he made an interesting observation.  I don't
remember his exact words, so I'll paraphrase:

* The first week after you return from a three month
    tour of duty in a submarine, it's nearly impossible
    to focus on anything more than 10 metres away.

The point is that when you've spent three months in a
space where nothing is more than 10 metres away, your eyes
haven't been exercised, and start to lose their ability to
adapt to distance.

Three months in a confined space ... sound familiar?

!! But wait ... there's more!

But there's another effect that's a little more subtle.

When you move around in a space you use the surrounding
physical cues to keep you oriented.  Effects like the one
at "Magnetic Hill"
''' <a href="https://en.wikipedia.org/wiki/Magnetic_Hill_(Moncton)">
(Magnetic Hill on Wikipedia)
''' </a>
are an example of how this can go wrong, and there are
several optical illusions based on this.

But if you've spent three months in a space with walls and
a ceiling, your brain adapts to using those to orient you.
And if they are then taken away, you can become disoriented
and suffer from vertigo and a lack of balance.

Hmm ... three months with walls and a ceiling ... does that
sound familiar?

!! Conclusions?

Again, for those of us content with our own company it's
/just/oh/so/tempting/ to stay in and simply not go out at
all.

But don't succumb to the temptation.  Go out, take a walk,
experience the very high ceiling, and the walls that are
just /so/ much further away.

It really does matter.

----

|>>
| |>> <<<< Prev <<<< ---- ParallelogramPuzzle <<| | : | |>> >>>> Next >>>> ---- RememberingConway ... <<| |
----
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[[[>
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********<

----

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