Month: April 2017

7 Science College Courses You Can Take Completely Free From Home

Interested in the environment? Are you partial to theplanetary sciences? Are youlooking to give your career a jumpstart? Its never been easier to learn about those subjects you’ve been curious about, but never had the means or time to explorefurther. Now, all you need is an Internet connection and a thirst for knowledge.

edXis a non-profit website that offers free education courses on a bunch of subjects from over 110 of the worlds top universities and institutions. The courses range from introductory to university level, all taught by leading researchers and experts in the field. Youcan also attend the classesfrom the comfort of your home with just a few hours of your time eachweek. So whats your excuse?

Check out a selection of their free courses below, ranging from the Earth sciences to astrophysics to science communication. In just a few clicks, you can start learning today!

Astrophysics: The Violent Universe

When it comes to unimaginably powerful forces and astronomical explosions, it does not get much more mind-blowing than the field of astrophysics. This self-paced course from the Australian National University gives an intermediate look at some of the most deadly forces and grand objects in the known universe, from neutron stars and white dwarfs to supernovae and even hypernovae.

Alexey Suloev/Shutterstock

Antarctica: From Geology To Human History

Victoria University of Wellington are offering youthechance to explore the coldest, driest, windiest, and coolest (no pun intended) continent on Earth: Antarctica

This course offers lessons onAntarctica’s 500 million years of geological history, as well as an insight into the 250 years of human and scientific exploration of this mysterious land. It also features virtual field trips and video lectures straight from Ross Island and the McMurdo Dry Valleys of Antarctica.

Climate Change: The Science

Climate change is undoubtedly one of the biggest and most controversial issues of our time, so its never been more important toknow the facts behind it.

Instructors from the University of British Columbia will give you the skills to understand and evaluate the latest science on climate change, as well as provide key expertise onways in which to communicate the scientific and human issues surrounding climate science to a wider audience.

Sensing Planet Earth From Core To Outer Space

This introductory course tells you everything you need to know about the different ways scientists use Earth observation tools, whether it be from space, aircraft, or on the ground. With the help of course instructors from Chalmers University of Technology, youll learn all you need to know to use, understand, and apply valuable observation data about our planet.

This Hubble Space Telescope image shows Supernova 1987A.Credit: NASA, ESA, R. Kirshner and M. Mutchler and R. Avila (STScI)

Greatest Unsolved Mysteries of the Universe

There’s no greater mystery than the universe. Just think, we don’t really know what most of the universe is even made of. Through this Australian National University course, you’ll learn many of the great questions raised by modern astrophysicsand understand why we’re so close, yet so very far, from answering them.

Question Everything: Scientific Thinking In Real Life

When you boil it down, science is simply a way of looking at the world. However,it doesnt just stop at scientific exploration, you can apply this way of seeing to all kinds of situations.This University of Queensland course shows how science can help you critically think about and appreciate the world around you. Its also perfect preparation if youre a high school student looking to further your interest in mathematics and science.

“Be more like this guy.” Shutterstock

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‘Granny style’ is best way to take a basketball free throw, study shows

Mathematical analysis reveals that for players with good control, using an unorthodox underarm technique gives better odds of scoring

It might invite ridicule, but it gets results. A scientific analysis has concluded that using a granny style underarm technique is the optimal way to take a free throw in basketball.

Adopting the unorthodox strategy could result in marginal gains for professional players, the research suggests. And, as sporting doctrine goes, marginal gains can lead to remarkable results.

Madhusudhan Venkadesan, who led the work at Yale University, said: Our mathematical analysis shows that if the thrower is capable of controlling the release angle and speed well, the underarm throw is slightly better for a basketball free throw.

However, it remains to be seen whether science will prove more persuasive than professional advocates of the underarm style.

The retired NBA player Rick Barry, a pioneer of the underarm free throw, was one of the most effective shooters of all time and when he retired in 1980 his 90% free throw record ranked first in NBA history. But he struggled to convince his teammates due to the inescapable fact that shooting underarm makes you look like a sissy, Barry said.

Venkadesan acknowledges that it is a difficult case to make.

One suspects there are social and cultural reasons you dont see that practised too often, he said. So what if some call it the granny throw? What matters is that the ball goes through the hoop! Rick Barrys record does support the underarm throw.

The study, published in the journal Royal Society Open Science, considered the chances of the ball being on target, depending on the style, speed and accuracy of a throw.

It found that if the player is capable of controlling the release angle and speed well, the underarm throw has slightly better odds of going in. But for amateurs who have only crude control, the release of the ball overarm is safer, sparing casual players the dilemma of choosing style or results.

An important factor in comparing the two strategies was how the ball approaches its target. When the ball approaches the net from directly above, as in a typical underarm throw, the cross-section of the target is large from the balls vantage point. This is good, as it means that if a throw is close to being exactly on target it has a very high chance of going in.

However, in trying to achieve this straight down entry, the amateur risks lobbing the ball extremely high due to their mediocre control. In this scenario, a small error in the timing of the release can cause the ball to grossly overshoot or undershoot the hoop.

So the overarm shot, where the ball sees a smaller cross-section of the hoop, but is less likely to go wildly off course, is a more conservative strategy.

This competition between the entry angle and speed underlies both the speed-accuracy trade-off and the relative accuracy of one style versus another, said Venkadesan.

For the professional player, the analysis predicts, this trade-off is finely balanced and probably within the margins of error of the model, which did not consider the backboard.

Barry, no doubt, would view the findings as confirmation of what he has argued all along. From the physics standpoint, its a much better way to shoot, he told the author Malcolm Gladwell in a recent interview. You have a little bit more margin for error than when you shoot overhand.

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Danica McKellar talks new project: ‘Theres this epidemic of kids being afraid of math’

When it comes to expressing a love for math, you can always count on Danica McKellar.

The 42-year-old actress, best known for playing Kevin Arnolds on-off girlfriend Winnie Cooper on The Wonder Years, has been keeping busy with her favorite subject.

My whole point, my whole mission is to make sure that kids never feel afraid of numbers. Never feel afraid of math, explained McKellar on FOX & Friends on Wednesday.

McKellar said plenty of people are intimidated by mathematics.

Theres this epidemic of kids being afraid of math, growing up that way, she said. Well, Im starting young. This is book one of eight that thatll be doing from Random House now, going through third grade. My mission is kids are never going to remember a time when numbers scare them.

She said her book is interactive.

But the fun thing about this book is that theres so many things to count on each page, she added. Ive snuck in a lot of math, including 10 frames on each page, to make your kids smarter.

McKellars new book, Goodnight, Numbers is the stars first picture book for children.

Aside from releasing a book, McKellar is also set to appear in the upcoming Hallmark film, Campfire Kiss, where she plays a single mom and math teacher who is forced to step outside of her comfort zone during a family camping trip.
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The new GCSE grades explained – BBC News

Image copyright Getty Images

As teachers express concerns about the way in which new GCSEs in England are being graded from 9-1 rather than A*-G, we answer some key questions about the changes.

When do the new 1-9 grades come in?

The new grades are being phased in, starting with some of this summer’s exams.

New-style GCSEs in English language, English literature and maths will be taken by the current Year 11 students – these exams will be graded in the new way, with nine as the highest mark and one the lowest.

A four is broadly being compared to a C grade, although the exams watchdog, Ofqual, warns against “direct comparisons and overly simplistic descriptions”.

For most other subjects – including biology, chemistry, physics, computer science, French, Spanish, religious education, geography, music and history – the new grades will be awarded from the summer of 2018.

A third wave of 9-1 graded GCSEs – including psychology, ancient history, business, information and communications technology (ICT) and media studies – will be taught from September 2017 with exams in 2019.

So some teenagers will have a mix of GSCEs under different marking schemes?

Yes, that’s right. The current Year 11s will get English and maths results under the new numerical grading scheme and the rest of their options will be graded A*-G.

The current Year 10 students will then sit most of their GCSEs under the new system, but they might have some under the old system, for example if they are taking ancient history or ICT, while those pupils now in Year 9 will be fully “moved over” on to the numerical grading system.

Image copyright PA

How do the new grades compare to the old ones?

Grades nine, eight and seven are broadly equivalent to an A* and A. Grades six, five and four are in line with B and C grades. A three would be broadly similar to a D grade, with two and one taking in grades E, F and G.

There is still a U (ungraded) mark.

Education Secretary Justine Greening says a grade four will be seen as a “standard pass” and a grade five as a “strong pass”.

She also says that for school performance tables, the government will publish “standard passes” (grade four and above) but also the “strong passes” (at grade five and above).

Watchdog Ofqual says that, broadly, the same proportion of teenagers will get a grade four and above as currently get a grade C or above.

It also says a formula will be used which will mean that about 20% of all grades at seven or above will be awarded a grade nine.

Chief regulator Sally Collier says students who get a nine will have “performed exceptionally”.

Won’t the first cohort to sit the new exams be disadvantaged?

It certainly feels like this and students in the next two year groups are guinea pigs for the new grading system.

However, Ofqual insists these students will not be disadvantaged.

It says that in 2016, in English and in maths, about 70% of 16-year-old students achieved a grade C or above and so it would expect a similar percentage to achieve a four and above in this summer’s exams.

Ofqual also says exam boards will use test results from national curriculum tests (Sats) taken at the end of primary school to predict the likely achievement at the new grades of one, four and seven.

Image copyright Getty Images

Why are GCSE grades in England being changed?

The new GCSE grading scheme is part and parcel of a new curriculum which was introduced in England’s schools in 2014 by the then Education Secretary Michael Gove.

The new GCSEs courses include much less coursework than before, with grades in almost all subjects depending on exams.

Courses are designed to be more rigorous with exams taken after two years of study, rather than in modules with exams along the way.

What is happening in Wales?

Change is under way in Wales as well as in England. The Welsh government has introduced new and revised GCSEs taught from September 2015.

The most significant changes are in English language, Welsh language and mathematics. In all the changed subjects, the new or revised specifications will be the only ones available to state schools in Wales. They will be delivered by the WJEC examination board.

One crucial difference to England is that the established grading structure of A*- G is being maintained.

Image copyright Getty Images

What is happening in Northern Ireland?

While pupils in England will have results graded 9-1 and pupils in Wales will have A*-G graded results, pupils in Northern Ireland could end up with a mix of A*-G and numerical grades.

Initially, the Northern Ireland government said all exam boards operating in the province must give their results on an A* to G basis. This led English exam boards OCR and AQA to announce they would not offer the new GCSEs there.

But in June 2016, this decision was reversed by new Education Minister Peter Weir and pupils will now be allowed to sit GCSE grades from English exam boards giving results using the 9-1 system.

Approximately three-quarters of GCSEs in Northern Ireland are taken through the NI Council for Curriculum, Examinations and Assessment (CCEA); the remaining quarter through the AQA, OCR, Edexcel or WJEC exam boards.

What about Scotland?

Scotland has its own system of public examinations: Nationals and Highers.

Nationals replaced the old Standard Grades in 2014 and new Higher exams were introduced in 2015.

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Paradoxes Of Probability And Other Statistical Strangeness

The Conversation

Statistics is a useful tool for understanding the patterns in the world around us. But our intuition often lets us down when it comes to interpreting those patterns. In this series we look at some of the common mistakes we make and how to avoid them when thinking about statistics, probability and risk. The Conversation

You dont have to wait long to see a headline proclaiming that some food or behaviour is associated with either an increased or a decreased health risk, or often both. How can it be that seemingly rigorous scientific studies can produce opposite conclusions?

Nowadays, researchers can access a wealth of software packages that can readily analyse data and output the results of complex statistical tests. While these are powerful resources, they also open the door to people without a full statistical understanding to misunderstand some of the subtleties within a dataset and to draw wildly incorrect conclusions.

Here are a few common statistical fallacies and paradoxes and how they can lead to results that are counterintuitive and, in many cases, simply wrong.

Simpsons paradox

What is it?

This is where trends that appear within different groups disappear when data for those groups are combined. When this happens, the overall trend might even appear to be the opposite of the trends in each group.

One example of this paradox is where a treatment can be detrimental in all groups of patients, yet can appear beneficial overall once the groups are combined.

How does it happen?

This can happen when the sizes of the groups are uneven. A trial with careless (or unscrupulous) selection of the numbers of patients could conclude that a harmful treatment appears beneficial.


Consider the following double blind trial of a proposed medical treatment. A group of 120 patients (split into subgroups of sizes 10, 20, 30 and 60) receive the treatment, and 120 patients (split into subgroups of corresponding sizes 60, 30, 20 and 10) receive no treatment.

The overall results make it look like the treatment was beneficial to patients, with a higher recovery rate for patients with the treatment than for those without it.

image-20170330-8593-t93w83.pngThe Conversation, CC BY-ND

However, when you drill down into the various groups that made up the cohort in the study, you see in all groups of patients, the recovery rate was 50% higher for patients who had no treatment.

image-20170330-30365-f2956l.pngThe Conversation, CC BY-ND

But note that the size and age distribution of each group is different between those who took the treatment and those who didnt. This is what distorts the numbers. In this case, the treatment group is disproportionately stacked with children, whose recovery rates are typically higher, with or without treatment.

Base rate fallacy

What is it?

This fallacy occurs when we disregard important information when making a judgement on how likely something is.

If, for example, we hear that someone loves music, we might think its more likely theyre a professional musician than an accountant. However, there are many more accountants than there are professional musicians. Here we have neglected that the base rate for the number of accountants is far higher than the number of musicians, so we were unduly swayed by the information that the person likes music.

How does it happen?

The base rate fallacy occurs when the base rate for one option is substantially higher than for another.


Consider testing for a rare medical condition, such as one that affects only 4% (1 in 25) of a population.

Lets say there is a test for the condition, but its not perfect. If someone has the condition, the test will correctly identify them as being ill around 92% of the time. If someone doesnt have the condition, the test will correctly identify them as being healthy 75% of the time.

So if we test a group of people, and find that over a quarter of them are diagnosed as being ill, we might expect that most of these people really do have the condition. But wed be wrong.

image-20170329-1664-htfx0x.pngIn a typical sample of 300 patients, for every 11 people correctly identified as unwell, a further 72 are incorrectly identified as unwell. The Conversation, CC BY-ND

According to our numbers above, of the 4% of patients who are ill, almost 92% will be correctly diagnosed as ill (that is, about 3.67% of the overall population). But of the 96% of patients who are not ill, 25% will be incorrectly diagnosed as ill (thats 24% of the overall population).

What this means is that of the approximately 27.67% of the population who are diagnosed as ill, only around 3.67% actually are. So of the people who were diagnosed as ill, only around 13% (that is, 3.67%/27.67%) actually are unwell.

Worryingly, when a famous study asked general practitioners to perform a similar calculation to inform patients of the correct risks associated with mammogram results, just 15% of them did so correctly.

Will Rogers paradox

What is it?

This occurs when moving something from one group to another raises the average of both groups, even though no values actually increase.

The name comes from the American comedian Will Rogers, who joked that when the Okies left Oklahoma and moved to California, they raised the average intelligence in both states.

Former New Zealand Prime Minister Rob Muldoon provided a local variant on the joke in the 1980s, regarding migration from his nation into Australia.

How does it happen?

When a datapoint is reclassified from one group to another, if the point is below the average of the group it is leaving, but above the average of the one it is joining, both groups averages will increase.


Consider the case of six patients whose life expectancies (in years) have been assessed as being 40, 50, 60, 70, 80 and 90.

The patients who have life expectancies of 40 and 50 have been diagnosed with a medical condition; the other four have not. This gives an average life expectancy within diagnosed patients of 45 years and within non-diagnosed patients of 75 years.

If an improved diagnostic tool is developed that detects the condition in the patient with the 60-year life expectancy, then the average within both groups rises by 5 years.

image-20170328-21243-1wcp3a8.pngThe Conversation, CC BY-ND

Berksons paradox

What is it?

Berksons paradox can make it look like theres an association between two independent variables when there isnt one.

How does it happen?

This happens when we have a set with two independent variables, which means they should be entirely unrelated. But if we only look at a subset of the whole population, it can look like there is a negative trend between the two variables.

This can occur when the subset is not an unbiased sample of the whole population. It has been frequently cited in medical statistics. For example, if patients only present at a clinic with disease A, disease B or both, then even if the two diseases are independent, a negative association between them may be observed.


Consider the case of a school that recruits students based on both academic and sporting ability. Assume that these two skills are totally independent of each other. That is, in the whole population, an excellent sportsperson is just as likely to be strong or weak academically as is someone whos poor at sport.

If the school admits only students who are excellent academically, excellent at sport or excellent at both, then within this group it would appear that sporting ability is negatively correlated with academic ability.

To illustrate, assume that every potential student is ranked on both academic and sporting ability from 1 to 10. There are an equal proportion of people in each band for each skill. Knowing a persons band in either skill does not tell you anything about their likely band in the other.

Assume now that the school only admits students who are at band 9 or 10 in at least one of the skills.

If we look at the whole population, the average academic rank of the weakest sportsperson and the best sportsperson are both equal (5.5).

However, within the set of admitted students, the average academic rank of the elite sportsperson is still that of the whole population (5.5), but the average academic rank of the weakest sportsperson is 9.5, wrongly implying a negative correlation between the two abilities.

image-20170329-1649-h3kvxl.pngThe Conversation, CC BY-ND

Multiple comparisons fallacy

What is it?

This is where unexpected trends can occur through random chance alone in a data set with a large number of variables.

How does it happen?

When looking at many variables and mining for trends, it is easy to overlook how many possible trends you are testing. For example, with 1,000 variables, there are almost half a million (1,000×999/2) potential pairs of variables that might appear correlated by pure chance alone.

While each pair is extremely unlikely to look dependent, the chances are that from the half million pairs, quite a few will look dependent.


The Birthday paradox is a classic example of the multiple comparisons fallacy.

In a group of 23 people (assuming each of their birthdays is an independently chosen day of the year with all days equally likely), it is more likely than not that at least two of the group have the same birthday.

People often disbelieve this, recalling that it is rare that they meet someone who shares their own birthday. If you just pick two people, the chance they share a birthday is, of course, low (roughly 1 in 365, which is less than 0.3%).

However, with 23 people there are 253 (23×22/2) pairs of people who might have a common birthday. So by looking across the whole group you are testing to see if any one of these 253 pairings, each of which independently has a 0.3% chance of coinciding, does indeed match. These many possibilities of a pair actually make it statistically very likely for coincidental matches to arise.

For a group of as few as 40 people, it is almost nine times as likely that there is a shared birthday than not.

image-20170329-1664-1tb8sti.pngThe probability of no shared birthdays drops as the number of people in a group increases. The Conversation, CC BY-ND

Stephen Woodcock, Senior Lecturer in Mathematics, University of Technology Sydney

This article was originally published on The Conversation. Read the original article.

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They had 15 hours to come up with an idea that’d improve lives. They did it.

They had 15 hours to come up with an idea for a revolutionary device that would make people’s lives better.

And they had to beat out hundreds of other teams that had some of the best student hackers in the world.

“Our first idea was a dancing robot that, like, danced with you if youre lonely in a dance club,” Charlene Xia said with a chuckle.

She and friends Chandani Doshi, Grace Li, Jialin Shi, Bonnie Wang, and Tania Yu were taking part in the MakeMIT hackathon MIT’s premier technology design competition. They and other students were tasked with coming up with a prototype for a new device.

Xia continued: “Then we moved to a braille watch that we saw a concept model of that somebody posted online. It got us thinking, ‘Well, wait a second, is there a thing like a text-to-braille converter? Like it translates and scans images of text on a book and converts it to braille when you move up and down?’ We kept googling and nothing came out.”

The young inventors began to lay the foundation for Tactile, the world’s first real-time text-to-braille converter.

It was a daunting challenge to say the least, but one that these young women, dubbed Team Tactile, were more than ready for.

“The good thing was that our team was very diverse,” said Shi. “We have people who studied material science, mechanical engineering, electrical engineering, and computer science.”

Of course, as most projects go, hurdles inevitably popped up. From the hourlong lines at the 3D printer to their code not working properly, it was one heck of a photo finish.

“Basically, nothing came together until the last 15 minutes,” added Shi. “Thats when we were finally able to take a picture of some text and finally translate that into some motor movement, which translated into a braille character. It was stressful, but it was definitely one of the highlights of our time here at MIT that moment when something you make from scratch finally works and your concept is realized.

Team Tactile ended up winning first place in the hackathon. But their journey was just getting started.

The team received incredible support and encouragement from the mentors involved with the hackathon and one mentor, in particular, had a lasting effect.

Paul Parravano is the co-director of MIT’s Government and Community Relations office. He’s been blind since age 3. He told Team Tactile that their invention could have a huge impact on the visually impaired community, especially since they experience many pain points when it comes to access to information no more than 5% of books are accessible to them.

Ultimately, providing someone who is visually impaired with the ability to read any book out in the world was too important not to pursue.

“The impact that we could potentially have in the future is really what drove us to continue working as a team,” said Wang. “Just working it out despite our problem sets, all the exams, projects and everything, we still keep going and just try to take the prototype as far as we can.”

“An audio translator won’t be able to translate all the mathematical signs and symbols,” said Shi. “Theres also everyday life something as simple as reading packaging labels and just knowing your surroundings. Not [having to ask] for help for every little thing.”

Right now, the team is still working to refine Tactile to make sure it’s as efficient and affordable as possible. After graduation, they plan to work on it full time, and they have their sights set on getting this invention into the hands of all those who truly need it whether in the U.S. or in the developing world.

Added Wang, “Ideally … one day, every visually impaired person will have a Tactile device something that they carry around with them every day and use on a daily basis to access the information around them.”

Team Tactile’s invention is so promising that they were selected to be a part of Microsoft’s #MakeWhatsNext Patent Program.

The program focuses on two things: helping young female inventors navigate the legal hurdles that come with securing patents and empowering young women to bridge the gender gap in STEM (science, technology, engineering, and mathematics).

“They really helped us take the stress away from the patent process and allowed us to focus on the technology the part that we’re passionate about developing,” said Wang.

Tactile is a great example of the type of life-changing innovation that can come from technology, and Microsoft is committed to ensuring that everyone especially young girls has access to computer science education resources so they, too, can unlock the power to create with technology.

“Why is that the case when you think of patents, you don’t think of women inventors?” wondered Xia. “Right now, there’s a movement towards building this community of women engineers and inventors, and we’re really happy and honored to be part of this movement and contribute as much as we can to make sure this movement continues and grows.”

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Can you solve it? The incredible sponge puzzle

This brainteaser will wring out your brain

Hi guzzlers.

For todays puzzle, let me introduce you to the Menger sponge, a fascinating object first described by the Austrian mathematician Karl Menger in 1926. Well get to the problem as soon as I explain what the object is.

The Menger sponge is a cube with smaller cubes extracted from it, and is constructed as follows: Step A: Take a cube. Step B: Divide it into 27 smaller subcubes, so it looks just like a Rubiks cube.



Step C: Remove the middle subcube in each side as well as the subcube at the centre of the cube, so if you looked through any hole you would see right through it. Step D: Repeat steps A to C for each of the remaining subcubes, that is, imagine that each subcube is made from 27 even smaller cubes and remove the middle one in each side and the central one.

We could carry on repeating steps A to C ad infinitum, on smaller and smaller subcubes, but here lets do it just once more:

Menger sponge. Illustration: Edmund Harriss/Visions of Numberland

Menger sponges are so loved within the maths community that building origami models of them out of business cards is a thing.

Menger sponge made as part of Matt Parker and Laura Taalmans MegaMenger project. Photograph: MegaMenger

There are lots* of reasons why Menger sponges are cool and one of them is illustrated by todays puzzle.

How to slice a cube in two.

On the left here is how you slice a cube in half such that the cross section is a hexagon.

When you slice a Menger sponge in two like this, what does the hexagonal slice look like?

This question is probably the most difficult one I have ever set in this column, as it requires phenomenal levels of spatial intuition. But I urge you to give it a go, even if just a basic sketch. Send me some images, or post them to me on social media. You may draw something along the right lines…

Please forgive me, though, for posing this toughie. The answer is jaw-droppingly amazing. In fact, I was told about the Menger slice by a respected geometer who told me it gave him probably his biggest wow moment in maths. Come back at 5pm BST and see for yourself.

NO SPOILERS PLEASE! Please talk about Karl Menger and origami instead.

Photograph: Bloomsbury

Both the Menger sponge and the Menger slice are included in my latest book, Visions of Numberland: A Colouring Journey Through the Mysteries of Maths. The book is a gallery of the most spectacular images that Edmund Harriss, my co-author, and I could find in maths. You can colour them in, or just contemplate them in black and white.

I set a puzzle here every two weeks on a Monday. Send me your email if you want me to alert you each time I post a new one.

Im always on the look-out for great puzzles. If you would like to suggest one, email me.

* Here are a couple. 1) Each time you follow the iteration described in steps A to C you decrease the volume of the sponge, but increase its surface area. After an infinite number of iterations, you will have removed an infinite number of cubes. The sponge will then have zero volume and infinite surface area. 2) After an infinite number of iterations, the object is a fractal, that is, it contains parts that are identical to the whole thing.

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Here’s the world’s favorite numberand why it makes perfect sense

The latest news from the none-of-your-thoughts-are-original department comes from mathematics blogger Alex Bellos, who set out to determine the worlds favorite number.

Bellos apparently doesnt have a favorite number himself, but as Nautiluswrites, he began asking people about their favorite numbers a few years ago, and after setting up theFavourite Numberwebsite, more than 44,000 people voted for the numeral they liked best and explained why.

Heres what Bellos discovered.

The third-most popular number is 8, because, as some of Belloss respondents wrote, In Japan, eight is a lucky number, because the Japanese character for eight means an opening to the future and because of its symmetrical and round shape and because it has always given me a sense of friendliness and warmth (unlike, for example, 9 which looks bossy or 6 which appears to me a bit submissive).

No. 2 on the list is the No. 3, because Its curly, but not pretentious curly like eight and because in Chinese, “3 means alive.

But the worlds most favorite number is No. 7. As for why, Bello will explain that himself. Its basically because of our desire to be outliers when it comes to arithmetical patterns.

As for why numbers ending in 0 or 5 are unpopular, Bellos said its because we use those numbers as approximations more than, say, 7 or 9.

When we say 100, we dont usually mean exactly 100, we mean around 100, Bellos told Nautilus. So 100 seems incredibly vague. Why would you have something as your favorite that is so vague?It seems that we like our numbers to be somewhat unique, which may be why prime numbers are popular. They arent divisible by any smaller numbers (aside from 1).

Belloss research was revealed in 2014, but his conclusion has been bouncing all over the internet for the past few days. Because your favorite number is probably a topic thatis endlessly fascinating.

Interestingly, the number 13 isnt as unpopular as you might think. It ranks as the sixth-most popular favorite number (but decidedly lower among people who have been hacked to pieces by Jason Voorhees).

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Space historian Amy Shira Teitel is changing the face of online educaiton

The Daily Dot is celebrating Woman Crush Wednesday, better known as #WCWonTwitterandInstagram, by highlighting female creators onYouTubewhose work we admire.

Like all great love stories, Amy Shira Teitels longtime affair with space history has been a winding and unpredictable road. She has turned this lifelong pursuit into a full-time business that has launched her as a writer and expert. Now the author, blogger, vlogger, and TV host is using her digital media presence to champion women in science, technology, engineering, and mathematics (S.T.E.M.)—making the often-academic topic of space accessible to anyone who is interested.

As a 7-year-old, Teitel presented a poster to her second-grade class on the many ways Venus was the opposite of Earth. But despite being obsessed with space and science throughout her education in Canada, Teitel soon realized that it was the history of science that intrigued her the most. After picking up a masters degree in science technology studies, a program that wasnt the right fit, Teitel moved to Phoenix. Not yet ready to pursue a Ph.D. but at a loss on how to pursue academia any other way, Teitel spent her days blogging on Vintage Spaceand nights working as a personal trainer. Four months into her blogging career, started in 2010, her Vintage Space articles began to gain traction across publications like Nerdist and the Guardian; Al Jazeera began asking her to write regular, original content.

With her niche blog gaining steam, Teitel decided to put a Ph.D. on the back burner to see what other unexpected opportunities might present themselves. In 2012, she first opened her YouTube channelas a space to make teasers for her blog posts, which were filing at a vast 2,500 words. The channel eventually transformed into a full-time education hub with videos covering everything about space exploration from the 1960s onward. Her videos quickly gained notice not only for their original content, but for the fact that she—a pink-haired cat lover with tattoos—was inspiring other women in the overly male dominated field of education on YouTube. It was her YouTube videos that sparked DNews to hire her as a regular host, and spurred her TV appearances on Science Channel, American Heroes Channel, SyFy, and the Travel Channel.

Like a skilled acrobat spinning plates without missing a step, Teitel added author to her business card in 2015 after publishing her debut book, Breaking the Chains of Gravity. After my deep research and years of watching her channel, I can confidently say that everything she puts her mind to will work out strongly.Her years of building a brand around her passion continue to show others that it is possible for them to do the same. So as young girls continue to push back against the boys’ club of S.T.E.M., Teitel stands as a heroine using her videos to shatter taboos around who and how someone can succeed in science.

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