How to make $138,000 from shredded banknotes – if you’re in Hong Kong

Money reunited

Chung To Kong found a way, in the spirit of unboiling an egg (Feedback, 10 September 2022), to make banknotes from shredded banknote pieces.

Kong, at the University of Hong Kong, writes: “At the Hong Kong Monetary Authority visitor center, visitors can buy a paperweight souvenir full of shredded banknotes. Even though the shredded banknotes are small, by using computer vision, it is possible to reconstruct the whole banknote like a jigsaw puzzle. Each paperweight souvenir costs $100 HKD, and it is claimed to contain shredded banknotes equivalent to 138 complete $1000 HKD banknotes. In theory, $138,000 HKD can be recovered by using computer vision.”

Kong visited the visitor centre, where he explained this to the staff. As a result, he says: “The paperweight souvenir is currently no longer available.” Anyone who wants to make money can get details from Kong’s paper, “The possibility of making $138,000 from shredded banknote pieces using computer vision“.

The big bite

Highly educated humans are trying to discern what happened in the earliest moments of two momentous events: a bite of chocolate and the birth of the universe. Maria Charalambides at Imperial College London and her team have been beavering at the bite mystery, much as many physicists have been beavering at learning what happened when the universe big-banged into existence.

Charalambides and her team’s study, “A multiscale finite element analysis model for predicting the effect of micro-aeration on the fragmentation of chocolate during the first bite“, is published in the European Journal of Mechanics – A/Solids. Their stated goal: to boldly go where no one has gone before in investigating “structures that reduce the calorific value while enhancing the taste perception”. They explored the final moment when chocolate is still fresh, before it is harshened by an encounter with digestive fluids.

Charalambides is no chocolate-is-the-entire-universe fanatic. She co-wrote the 1995 classic paper “A study of the influence of ageing on the mechanical properties of Cheddar cheese“. It tells how her team dropped hunks of cheese from various heights. This produced fractured cheese and loads of data – two quantities that, if consumed individually, bring nourishment and joy to large chunks of humanity.

Feasible beer glasses

In the UK, where warm beer is either treasured or tolerated, a study called “Optimizing beer glass shapes to minimize heat transfer during consumption” might raise eyebrows. In Brazil, where warm beer can be mildly dreaded, this is cool research. Mason Porter stoutly brought it to Feedback’s attention.

The author, Cláudio de Castro Pellegrini at Federal University of São João del-Rei in Brazil, identifies two “feasible” shapes. Both, he says, “have total volumes considered high by most non-alcoholic consumers and considerably large radius of the opening, requiring a wide foot to keep balance”. But he warns that “as in the case of cutting pizzas, the mathematically optimized solution to the problem may prove to be somewhat complicated to implement in practice”.

237-fold gifting

For Mansi Gupta and her team, the existence of gift-giving is itself a gift to be appreciated. And analysed. Gupta is lead author on a study called “A bibliometric analysis on gift giving“, published in Psychology & Marketing.

Gupta, based at Lal Bahadur Shastri Institute of Management in India, and her team say that although “consumer gift-giving behavior has received much attention from marketing scholars”, they decided to “conduct a bibliometric analysis of 237 articles on gift-giving”. The stated main accomplishments: the paper gives readers “a state- of-the-art overview of consumer gift-giving literature and identifies opportunities for future gift-giving research”.

Pivotal ketchup

The discussion of having robots use ketchup as a non-Newtonian fluid suitable for polishing glass surfaces (Feedback, 16 March 2024) prompts us to recall an earlier unexpected use of ketchup. A half-century ago, ketchup became a red-flag psychology discussion topic. Calvin Trillin later wrote about it, in the magazine The Nation.

Trillin observed that, prior to his forced resignation from office, US President Richard Nixon “was noted for lunching at his desk on cottage cheese with ketchup on it – a dish most Americans found so bizarre that its appeal to Nixon was used by his enemies as a comment on his character. During his second term, the White House put out the word that the President had begun to eat his cottage cheese without ketchup – presumably hoping that this information would be used by Washington commentators as evidence that Nixon had, in the phrase Washington commentators have always loved, grown in the presidency.

“That might have happened, except for one problem: Since the information on ketchup had come from the Nixon White House in his second term, nobody believed it.”

Feedback would be interested to learn of other pivotal roles that ketchup has played in science or world history. Ditto brown sauce.

Marc Abrahams created the Ig Nobel Prize ceremony and co-founded the magazine Annals of Improbable Research. Earlier, he worked on unusual ways to use computers. His website is improbable.com.

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