Once a week.
Subscribe to our weekly newsletter.
The Shortest Route Between All the Pubs in the UK
Plotting out the world's longest pub crawl had a serious, mathematical point
From John o' Groats to Land's End (1) – that proverbial phrase covers the entire island of Great Britain. Here is a novel one: from the Bells But & Ben in Yell to the Witchball in The Lizard. That's the northernmost and southernmost pub in Britain, respectively. This map shows the shortest route between both – and every other pub in the UK, all 24,725 of them. That is one massive pub crawl.
But why? Computational mathematics, is why. This monster of a map is a solution to a cartographic conundrum called the Travelling Salesman Problem (2).
Suppose you are a salesman presenting your wares at several locations today. The problem: work out the shortest route between all, taking into account that you need to start from home and arrive back there at the end of the day. For a small number of locations, the solution to that problem usually is self-evident. Add enough locations, and the solution becomes more difficult. Difficult enough for a manual to be published in 1832 called Der Handlungsreisende, proposing a number of routes for salesmen travelling through Germany and Switzerland.
The solutions it proposed were based on experience, but the Travelling Salesman Problem (TSP) tantalised scientists, who sought to formulate a universal answer. The first to come to grips with the problem was the 19th-century Irish mathematician W.R. Hamilton, who developed the icosian game, the purpose of which is to find a Hamiltonian cycle in a dodecahedron (cf. inf.): a circuit that starts and ends at the same point, and visits all other points only once (3).
Another important TSP theorist was Viennese mathematician Karl Menger, who in the 1930s conceded that
“of course, this problem is solvable by finitely many trials, but rules which would push the number of trials below the number of permutations of the given points are not known. The rule that one first should go from the starting point to the closest point, then to the point closest to this, etc., in general does not yield the shortest route”.
As Menger states, the easiest solution to the TSP is to simply to try all options. But even for a relatively low number of locations, the number of variables is enormous – for just 10 cities there are over 180,000 combinations, for example.
But a systematic solution remains elusive even today, as computers are currently able to calculate solutions for millions of points only to within 2% to 3% of the optimal result (4).
The TSP has many useful applications, from finding the shortest mailman routes to devising the optimal sequence to drill holes in circuit boards, and even calculating the easiest way for Santa to complete his annual one-night tour of all the chimneys in the world. Perhaps the most important consequence of the TSP is that there are no known algorithms to crack the codes on which we rely to keep our data secure.
Finding the shortest route between all pubs in Great Britain may not have figured high on the list of TSP issues to be solved, but solved it now has been, thanks to the Faculty of Mathematics at the University of Waterloo in Canada.
They attacked the TSP by mapping out the shortest-possible walking tour through the pubs of the United Kingdom, or as they so scientifically called the project: UK24727, after the number of pubs (5) involved. Some stats:
This line drawing conveys the route of the tour, which also includes ferry excursions off the British mainland for pub tours in the Hebrides, Orkney and Shetland islands, the isle of Man and Northern Ireland.
The entire map, with a Google Maps markers for each of the pubs, gives the impression that most of Britain is covered by an unbroken canopy of red balloons – darker areas indicating a concentration of balloon ridges, where the greater density of pubs suggests the presence of large cities.
Apart from solving a mathematical problem, the map also has an obvious practical use, for planning your next pub crawl. Attempting the entire route is not recommended, but zoom in to certain areas or the cities listed in the menu on the right, and plot your next excursion.
Like this drinking trip of the Hebrides: arrive by ferry from Oban, slake your thirst at the Am Politician in South Uist, wet your whistle at the Langass Lodge in Loch Eport, polish your pint at Harmersay House in Lochmaddy and get one for the road in the Carlton at Stornoway, before jumping on the ferry back to the mainland at Ullapool (where you can continue indulging at the Ceilidh Place).
Or why not find the watering holes closest to the UK's other two extremities: have a session the Black Cat in Belleek, the westernmost pub in the realm, and take in spirits at the Royal Falcon in Lowestoft, probably the easternmost pub – there are quite a few bunched together in that area, so you might have to visit a few more.
Visit the legendary watering holes of London in the time-saving succession devised by these thirsty mathematicians: make your way from De Hems to the French House via the Golden Lion and then on to... wait, weren't we going in the other direction? Doesn't matter: thanks to this Hamiltonian cycle, we'll end up here again eventually.
Having devised the world’s longest pub crawl, the TSP team at Waterloo University is gearing up for the next challenge: sending their putative salesman on the shortest possible tour past all 49,603 places listed in the U.S. National Register of Historic Places. “This problem is quite a beast”, they admit.
“We currently have a tour of length 350,201,525 meters. That is a little less than the distance to the moon. But we don't know if this is actually the shortest tour. There might possibly be a tour that is 196 meters shorter than our tour. Ouch! Close is just not good enough”.
Find the entire map here. Warning: loads slowly! For more information on the UK pub crawl, and other road-TSP projects covering 120 German cities, 50 U.S. landmarks and others, see the TSP page at the University of Waterloo’s Mathematics Faculty. Many thanks to Joel Winten and Folkard Wohlgemuth for sending in this map.
Strange Maps #818
Got a strange map? Let me know at email@example.com.
(1) John o' Groats, in Scottish Gaelic Taigh Iain Ghròt, is a village of 300 at the northern tip of the Scottish mainland. It is the northernmost inhabited place in Great Britain. Dunnet Head, about fifteen miles (24 km) to the east, is the northernmost place per se. John o' Groats was named after Jan de Groot, a Dutchman who operated a ferry from here to Orkney around the year 1500.
Land's End, in Cornish Penn an Wlas, is a headland and holiday resort at the western tip of Britain (7), on the Penwith peninsula in Cornwall. It is about 33 miles (53 km) east of Lizard Point, Britain's southernmost extremity. The 838 miles (1,349 km) trip between John o' Groats and Land's End is the longest one possible between two inhabited places in Britain.
(2) Or in this case, the Travelling Alesman Problem.
(3) Related to the Seven Bridges of Königsberg problem, proven by Euler to be unsolvable. More on that at #536.
(4) For actual travelling salesmen, not the theoretical ones dreamt up by Hamilton, Menger e.a., the TSP is even more complex, for distance is only one of the variables; the more important ones are time and money: How long does it take to get anywhere, and how much does it cost? For example, is it worth it to take the plane instead of the car to get from A to B and C and back to A again? That depends on whether the value of the time saved outweighs the value of the extra money spent.
(5) Since the exact number of pubs fluctuates due to closures and openings of various establishments, the study was based on the 24,727 pubs as listed in on the Pubs Galore website.
(6) I.c. the route connecting the 200 Tesla superchargers in the United States, a road-TSP problem solved by Mortada Meyhar. Below his map of the Travelling Tesla Salesman.
(7) Actually, the westernmost point of England, but not of Britain. As reader Kevin Jones points out, "the most westerly point of mainland island of Great Britain is Corrachadh Mòr, only 0.5 degree further west than Land's End. If you are ever in Scotland, it is wonderful place to visit, with its views over the islands of the Inner Hebrides. The geology is very interesting, it being a remnant of an igneous complex from the splitting of the North Atlantic about 60 million years ago".
How would the ability to genetically customize children change society? Sci-fi author Eugene Clark explores the future on our horizon in Volume I of the "Genetic Pressure" series.
- A new sci-fi book series called "Genetic Pressure" explores the scientific and moral implications of a world with a burgeoning designer baby industry.
- It's currently illegal to implant genetically edited human embryos in most nations, but designer babies may someday become widespread.
- While gene-editing technology could help humans eliminate genetic diseases, some in the scientific community fear it may also usher in a new era of eugenics.
Tribalism and discrimination<p>One question the "Genetic Pressure" series explores: What would tribalism and discrimination look like in a world with designer babies? As designer babies grow up, they could be noticeably different from other people, potentially being smarter, more attractive and healthier. This could breed resentment between the groups—as it does in the series.</p><p>"[Designer babies] slowly find that 'everyone else,' and even their own parents, becomes less and less tolerable," author Eugene Clark told Big Think. "Meanwhile, everyone else slowly feels threatened by the designer babies."</p><p>For example, one character in the series who was born a designer baby faces discrimination and harassment from "normal people"—they call her "soulless" and say she was "made in a factory," a "consumer product." </p><p>Would such divisions emerge in the real world? The answer may depend on who's able to afford designer baby services. If it's only the ultra-wealthy, then it's easy to imagine how being a designer baby could be seen by society as a kind of hyper-privilege, which designer babies would have to reckon with. </p><p>Even if people from all socioeconomic backgrounds can someday afford designer babies, people born designer babies may struggle with tough existential questions: Can they ever take full credit for things they achieve, or were they born with an unfair advantage? To what extent should they spend their lives helping the less fortunate? </p>
Sexuality dilemmas<p>Sexuality presents another set of thorny questions. If a designer baby industry someday allows people to optimize humans for attractiveness, designer babies could grow up to find themselves surrounded by ultra-attractive people. That may not sound like a big problem.</p><p>But consider that, if designer babies someday become the standard way to have children, there'd necessarily be a years-long gap in which only some people are having designer babies. Meanwhile, the rest of society would be having children the old-fashioned way. So, in terms of attractiveness, society could see increasingly apparent disparities in physical appearances between the two groups. "Normal people" could begin to seem increasingly ugly.</p><p>But ultra-attractive people who were born designer babies could face problems, too. One could be the loss of body image. </p><p>When designer babies grow up in the "Genetic Pressure" series, men look like all the other men, and women look like all the other women. This homogeneity of physical appearance occurs because parents of designer babies start following trends, all choosing similar traits for their children: tall, athletic build, olive skin, etc. </p><p>Sure, facial traits remain relatively unique, but everyone's more or less equally attractive. And this causes strange changes to sexual preferences.</p><p>"In a society of sexual equals, they start looking for other differentiators," he said, noting that violet-colored eyes become a rare trait that genetically engineered humans find especially attractive in the series.</p><p>But what about sexual relationships between genetically engineered humans and "normal" people? In the "Genetic Pressure" series, many "normal" people want to have kids with (or at least have sex with) genetically engineered humans. But a minority of engineered humans oppose breeding with "normal" people, and this leads to an ideology that considers engineered humans to be racially supreme. </p>
Regulating designer babies<p>On a policy level, there are many open questions about how governments might legislate a world with designer babies. But it's not totally new territory, considering the West's dark history of eugenics experiments.</p><p>In the 20th century, the U.S. conducted multiple eugenics programs, including immigration restrictions based on genetic inferiority and forced sterilizations. In 1927, for example, the Supreme Court ruled that forcibly sterilizing the mentally handicapped didn't violate the Constitution. Supreme Court Justice Oliver Wendall Holmes wrote, "… three generations of imbeciles are enough." </p><p>After the Holocaust, eugenics programs became increasingly taboo and regulated in the U.S. (though some states continued forced sterilizations <a href="https://www.uvm.edu/~lkaelber/eugenics/" target="_blank">into the 1970s</a>). In recent years, some policymakers and scientists have expressed concerns about how gene-editing technologies could reanimate the eugenics nightmares of the 20th century. </p><p>Currently, the U.S. doesn't explicitly ban human germline genetic editing on the federal level, but a combination of laws effectively render it <a href="https://academic.oup.com/jlb/advance-article/doi/10.1093/jlb/lsaa006/5841599#204481018" target="_blank" rel="noopener noreferrer">illegal to implant a genetically modified embryo</a>. Part of the reason is that scientists still aren't sure of the unintended consequences of new gene-editing technologies. </p><p>But there are also concerns that these technologies could usher in a new era of eugenics. After all, the function of a designer baby industry, like the one in the "Genetic Pressure" series, wouldn't necessarily be limited to eliminating genetic diseases; it could also work to increase the occurrence of "desirable" traits. </p><p>If the industry did that, it'd effectively signal that the <em>opposites of those traits are undesirable. </em>As the International Bioethics Committee <a href="https://academic.oup.com/jlb/advance-article/doi/10.1093/jlb/lsaa006/5841599#204481018" target="_blank" rel="noopener noreferrer">wrote</a>, this would "jeopardize the inherent and therefore equal dignity of all human beings and renew eugenics, disguised as the fulfillment of the wish for a better, improved life."</p><p><em>"Genetic Pressure Volume I: Baby Steps"</em><em> by Eugene Clark is <a href="http://bigth.ink/38VhJn3" target="_blank">available now.</a></em></p>
A leading British space scientist thinks there is life under the ice sheets of Europa.
- A British scientist named Professor Monica Grady recently came out in support of extraterrestrial life on Europa.
- Europa, the sixth largest moon in the solar system, may have favorable conditions for life under its miles of ice.
- The moon is one of Jupiter's 79.
Neil deGrasse Tyson wants to go ice fishing on Europa<div class="rm-shortcode" data-media_id="GLGsRX7e" data-player_id="FvQKszTI" data-rm-shortcode-id="f4790eb8f0515e036b24c4195299df28"> <div id="botr_GLGsRX7e_FvQKszTI_div" class="jwplayer-media" data-jwplayer-video-src="https://content.jwplatform.com/players/GLGsRX7e-FvQKszTI.js"> <img src="https://cdn.jwplayer.com/thumbs/GLGsRX7e-1920.jpg" class="jwplayer-media-preview" /> </div> <script src="https://content.jwplatform.com/players/GLGsRX7e-FvQKszTI.js"></script> </div>
Water Vapor Above Europa’s Surface Deteced for First Time<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="9c4abc8473e1b89170cc8941beeb1f2d"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/WQ-E1lnSOzc?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
Scientists discover burrows of giant predator worms that lived on the seafloor 20 million years ago.
- Scientists in Taiwan find the lair of giant predator worms that inhabited the seafloor 20 million years ago.
- The worm is possibly related to the modern bobbit worm (Eunice aphroditois).
- The creatures can reach several meters in length and famously ambush their pray.
A three-dimensional model of the feeding behavior of Bobbit worms and the proposed formation of Pennichnus formosae.
Credit: Scientific Reports
Beware the Bobbit Worm!<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="1f9918e77851242c91382369581d3aac"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/_As1pHhyDHY?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
The idea behind the law was simple: make it more difficult for online sex traffickers to find victims.
- SESTA (Stop Enabling Sex Traffickers Act) and FOSTA (Allow States and Victims to Fight Online Sex Trafficking Act) started as two separate bills that were both created with a singular goal: curb online sex trafficking. They were signed into law by former President Trump in 2018.
- The implementation of this law in America has left an international impact, as websites attempt to protect themselves from liability by closing down the sections of their sites that sex workers use to arrange safe meetings with clientele.
- While supporters of this bill have framed FOSTA-SESTA as a vital tool that could prevent sex trafficking and allow sex trafficking survivors to sue those websites for facilitating their victimization, many other people are strictly against the bill and hope it will be reversed.
What is FOSTA-SESTA?<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="723125b44601d565a7c671c7523b6452"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/WBaqDjPCH8k?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>SESTA (Stop Enabling Sex Traffickers Act) and FOSTA (Allow States and Victims to Fight Online Sex Trafficking Act) were signed into law by former President Trump in 2018. There was some argument that this law may be unconstitutional as it could potentially violate the <a href="https://constitution.congress.gov/constitution/amendment-1/" target="_blank">first amendment</a>. A criminal defense lawyer explains this law in-depth in <a href="https://www.youtube.com/watch?v=RoWx2hYg5uo&t=38s" target="_blank" rel="nofollow">this video</a>. </p><p><strong>What did FOSTA-SESTA aim to accomplish?</strong></p><p>The idea behind the law was simple: make it more difficult for online sex traffickers to find victims. FOSTA-SESTA started as two separate bills that were both created with a singular goal: curb online sex trafficking. Targeting websites like Backpage and Craigslist, where sex workers would often arrange meetings with their clientele, FOSTA-SESTA aimed to stop the illegal sex-trafficking activity being conducted online. While the aim of FOSTA-SESTA was to keep people safer, these laws have garnered international speculation and have become quite controversial. </p><p><a href="https://www.businesswire.com/news/home/20180321006214/en/National-Anti-Trafficking-Coalition-Celebrates-Survivors-Senate-Passes" target="_blank" rel="noopener noreferrer">According to BusinessWire</a>, many people are in support of this bill, including the National Center for Missing and Exploited Children and World Without Exploitation (WorldWE). </p><p>"With the growth of the Internet, human trafficking that once happened mainly on street corners has largely shifted online. According to the National Center for Missing & Exploited Children, 73 percent of the 10,000 child sex trafficking reports it receives from the public each year involve ads on the website Backpage.com."</p><p>As soon as this bill was <a href="https://www.pivotlegal.org/sesta_fosta_censoring_sex_workers_from_websites_sets_a_dangerous_precedent" target="_blank" rel="noopener noreferrer">signed into law</a>, websites where sex workers often vetted and arranged meetings with their clients could now be held liable for the actions of the millions of people that used their sites. This meant websites could be prosecuted if they engaged in "the promotion or facilitation of prostitution" or "facilitate traffickers in advertising the sale of unlawful sex acts with sex trafficking victims." </p><p><strong>The bill's effects were felt around the world — from Canadians being unhappy with the impact of this American bill to U.K. politicians considering the implementation of similar laws in the future.</strong> </p><p>Heather Jarvis, the program coordinator of the Safe Harbour Outreach Project (SHOP), which supports sex workers in the St. John's area, <a href="https://www.cbc.ca/news/canada/newfoundland-labrador/heather-jarvis-website-shutdown-1.4667018" target="_blank" rel="noopener noreferrer">explained to CBC in an interview</a> that the American bill is impacting everyone, everywhere: "When laws impact the internet — the internet is often borderless — it often expands across different countries. So although these are laws in the United States, what we've seen is they've been shutting down websites in Canada and other countries as well."</p><p>Jarvis suggests in her interview that instead of doing what they aimed to do with the bill and improving the safety of victims of sex trafficking or sexual exploitation, the website shutdowns are actually making sex workers less safe. </p><p>While <a href="https://gizmodo.com/the-uk-wants-its-own-version-of-fosta-sesta-that-could-1827420794" target="_blank" rel="noopener noreferrer">one U.K. publication</a> refers to FOSTA-SESTA as "well-intentioned but ultimately deeply-flawed laws," it also mentions that politicians in the United Kingdom are hoping to pursue similar laws in the near future. </p>
Has FOSTA-SESTA done more harm than good?<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTUxMzY5Ny9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY2ODUyNDc4OX0.dSEEzcflJJUTnUCFmuwmPAIA0f754eW7rN8x6L7fcCc/img.jpg?width=1245&coordinates=-68%2C595%2C-68%2C595&height=700" id="69d99" class="rm-shortcode" data-rm-shortcode-id="734759fa254b5a33777536e0b4d7b511" data-rm-shortcode-name="rebelmouse-image" alt="sex worker looking online for a job" data-width="1245" data-height="700" />
Is this really going to help, or is this bill simply pushing sex work and sex-related content further into the dark?
Credit: Евгений Вершинин on Adobe Stock<p>While <a href="https://www.businesswire.com/news/home/20180321006214/en/National-Anti-Trafficking-Coalition-Celebrates-Survivors-Senate-Passes" target="_blank">supporters of this bill</a> have framed FOSTA-SESTA as a vital tool that could prevent sex trafficking and allow sex trafficking survivors to sue those websites for facilitating their victimization, many other people are strictly against the bill and hope it will be reversed.</p><p><strong>One of the biggest problems many people have with this bill is that it forces sex workers into an even more dangerous situation, which is quite the opposite of what the bill had intended to do.</strong> </p><p>According to <a href="https://www.theglobeandmail.com/canada/article-anti-trafficking-activists-cheer-but-sex-workers-bemoan-shutdown-of/" target="_blank" rel="noopener noreferrer">Globe and Mail</a>, there has been an upswing in pimps sending sex workers messages that promise work - which puts sex workers on the losing end of a skewed power-dynamic, when before they could attempt to safely arrange their own meetings online. </p><p><strong>How dangerous was online sex work before FOSTA-SESTA? </strong></p><p><a href="https://www.beyond-the-gaze.com/wp-content/uploads/2018/01/BtGbriefingsummaryoverview.pdf" target="_blank" rel="noopener noreferrer">The University of Leicester Department of Criminology</a> conducted an online survey that focused on the relative safety of internet-based sex work compared with outdoor sex work. According to the results, 91.6 percent of participants had not experienced a burglary in the past 5 years, 84.4 percent had not experienced physical assault in the same period, and only 5 percent had experienced physical assault in the last 12 months. </p><p><a href="https://www.pivotlegal.org/sesta_fosta_censoring_sex_workers_from_websites_sets_a_dangerous_precedent" target="_blank" rel="noopener noreferrer">PivotLegal</a> expresses concerns about this: "It is resoundingly clear, both from personal testimony and data, that attacking online sex work is an assault on the health and safety of people in the real world. In a darkly ironic twist, SESTA/FOSTA, legislation aimed at protecting victims of and preventing human trafficking for the purposes of sexual exploitation, will do the exact opposite."</p><p><strong>Websites are also being hypervigilant (and censoring more content than needed) because they can't possibly police every single user's activity on their platform.</strong> </p><p>Passing this bill meant any website (not just the ones that are commonly used by sex traffickers) could be held liable for their user's posts. Naturally, this saw a general "tightening of the belt" when it came to what was allowed on various platforms. In late 2018, shortly after the FOSTA-SESTA bill was passed, companies like Facebook slowly began to alter their terms and conditions to protect themselves. </p><p>Facebook notably added sections that express prohibited certain sexual content and messages:</p><p style="margin-left: 20px;"><em>"Content that includes an implicit invitation for sexual intercourse, which can be described as naming a sexual act and other suggestive elements including (but not limited to):</em></p><p style="margin-left: 20px;"><em>– vague suggestive statements such as: 'looking forward to an enjoyable evening'</em></p><p style="margin-left: 20px;"><em>– sexual use of language […]</em></p><p style="margin-left: 20px;"><em>– content (self-made, digital or existing) that possibly portrays explicit sexual acts or a suggestively positioned person/suggestively positioned persons."<br><br> </em></p><p>Additionally, sections like this were also added, prohibiting things that could allude to sexual activity: </p><p style="margin-left: 20px;"><em>"Content in which other acts committed by adults are requested or offered, such as:</em></p><p style="margin-left: 20px;"><em>– commercial pornography</em></p><p style="margin-left: 20px;"><em>– partners that share fetishes or sexual interests"</em></p><p>Facebook wasn't the only website to crack down on their policies — the Craigslist classifieds section being removed and Reddit banned quite a large number of sex-worker related subreddits. </p><p><strong>Is FOSTA-SESTA really helpful?</strong> </p><p>This is the question many people are facing with the FOSTA-SESTA acts being passed just a few years ago. Is this really going to help, or is this bill simply pushing sex work and sex-related content further into the dark? Opinions seem to be split down the middle on this — what do you think?</p>