# Science Fiction got there first (again)

Back in High School (1964-68) I read a lot of science fiction by Mack Reynolds. His Joe Mauser series is set in a world where the cold war continues into the 21st century, but, to avoid catastrophe, the West and the “Sov-world” have agreed to restrict all military forces to pre-1900 technology. There is still lots of fighting going on at that level.

Recently I was reading about the decades old border dispute between between China and India countries, which actually led to war in 1962. The conflict still simmers on, but a 1996 agreement states that

Neither side shall open fire, cause bio-degradation, use hazardous chemicals, conduct blast operations or hunt with guns or explosives within two kilometers from the line of actual control.

Neither side wants to get the blame for starting a shooting war, so both sides are following the letter of the agreement. However, nobody is backing down. There have been reports that “Chinese troops have used improvised edged weapons, such as nail-studded clubs, in … skirmishes with Indian forces.” and both sides have martial artists in their border forces.

It seems that the Chinese are escalating. We now have Chinese soldiers armed with new devices for hand-to-hand combat with Indians in Tibet. Actually the “new device”, the guan dao, is quite old. It similar to a a western medieval halberd. It will be interesting to see how Indian army responds. They have a rich tradition of edged weapons to draw upon.

# Calculating a limit

Today I saw this problem on Medium: Compute the limit

Followed by “Pause the article and attempt a solution now.” (Don’t cheat and look ahead)

So I did. I do not really like factorials, so I immediately thought of Stirling’s approximation:

ln n! ≃ n ln nn as n → ∞

and all of the n‘s cancelled, leaving the result 1/e. I then looked at the author’s solution. My answer was correct, but he used a completely different approach, as you can see. I posted my solution, and got a nice complement from him.

This is Thanksgiving day in the USA. I am thankful that my calculus skills are still pretty good decades after my last formal course in that or any related field .

# Rang Gaeilge, 24ú lá Mí na Samhna 2020

#### Duinnín agus an Cat (tuilleadh)

• ‘Tá an gloine briste i ndoras uimhir a 33,’ arsa Eleanór, ‘díreach mar a bheadh i ndoras Mharia murach gur imir tú cleas ar an nglas.’
‘Féach an sneachta os comhair an dorais [g],’ ar sise. ‘B’é go raibh cruinniú poiblí ar an táirseach?’
‘Dráma, seachas cruinniú, déarfainn,’ arsa an Duinníneach. ‘An rian is tábhachtaí ná an ceann sin ar clé ar fad.’
‘Is geall le rian coise eilifint é.’

‘The glass is broken in door number 33,’ Eleanor said , ‘just like it would be in Maria’s door if you hadn’t played a trick on the lock.’
‘Look at the snow in front of the door,’ she said. Was there a public meeting on the threshhold?’
‘Drama, rather than a meeting, I would say,’ said Dineen. ‘The most important track is that one on the far left. It is like an elephant’s footprint.’

 cruinniú Gathering, Meeting m poiblí publie táirseach threshhold rian Course, path; Mark, trace, track; Power of movement, vigor m geall Pledge, security; Wager, bet; promise m Is geall le It is like

• ‘Cuimhnigh go raibh bróga tí á gcaitheamh ag Maria. Faoin am seo, bheidís báite fliuch agus éadach na n-uachtar ag sliobarnaíl thar na boinn. Tá na coiscéimeanna eile anuas ar na cinn aici siúd.’
‘An méid atá iontu!’ arsa Eleanor go himníoch. ‘Fiú agus méadú le linn leá a chur san áireamh! . . . Feicim fathaigh, abominable snowmen, dosaen garraíodóir ar thóir Mharia.’
‘Siúil anseo i lár an chosáin mar a bhfuil an sneachta leáite.’
‘Fuil!’ arsa Eleanór agus uafás uirthi.
‘Braonta ar fud na háite,’ a d’aontaigh an Duinníneach.
Chuir sé lámh trín bpoll agus d’oscail sé an doras.

Remember Maria was wearing house shoes. By this time, they would be drenched wet and the cloth on top drooping over the soles. The other footsteps are on top of hers.
‘The size of them!’ said Eleanor anxiously. ‘Even considering the increase during melting! . . . I see giants, abominable snowmen, a dozen gardeners in search of Maria.’
‘Walk here in the middle of the path where the snow has melted.’
‘Blood!’ said Eleanor in horror.
‘Drops all over the place,’ agreed Dineen.
He put his hand through the hole and opened the door.

 báite drowned éadach cloth m uachtar top, upper part; cream m ag sliobarna = ag liobarna hanging loose, drooping bonn sole m méadú increase m leá melting, dissolution m áireamh counting, reckonning fathach giant m ar thóir in search of cosán Path; Footway, track; Way, passage; direction m fuil blood f uafás Horror, terror m aontaigh unite; agree