Monthly Archives: September 2016

Summer PopSci Reading

I just love popular science… as you may have noticed. This year, I read a lot of popular science books, especially whilst travelling to and from the various conferences I went to, and the holidays I went on, over the summer. (Oh yeah, did I mention I go to conferences now? How cool is that?) I thought it might be fun to go through the books I read this summer and give them a review. So, in reverse reading order:

Alex’s Adventures in Numberland — Alex Bellos

Alex Bellos is a regular on my beloved Numberphile YouTube channel, and he wrote a book a few years ago about more of the human side of mathematics. I only picked it up recently, but it was a good read. It was very breezy, simple, fun, and engaging. Most of the chapters in the book were dedicated to people who are doing fun, quirky things you wouldn’t normally associate with maths: things like thinking of silly puzzles in magazine columns, or doing origami, or Rubik’s Cubes, or making non-Euclidean geometries… with crochet!

But what Bellos does well is convince you that these weird sideshows are real maths, they matter just as much as topology, or calculus, or number theory… and what these people are doing is actually really fun and interesting! It’s full of interviews with the actual people doing these things, so you get to hear in their own words why what they do matters. Bellos is an experienced travel writer, and it really does feel like a travel blog from the exotic country of Numberland.

It also has just enough of a primer on the actual maths involved to engage science nerds like me who like the gory details. I thought it could have used a bit more of this, and some of the actual maths explanations, like about the history of numbers, or Euclid’s geometry, I’ve seen done better elsewhere, but maybe that’s just me.

Accessible? – – – – – – 9.5/10
Interesting subject? – – 7.0/10
Science content? – – – 6.5/10
Well written? – – – – – 7.0/10
Overall score? – – – – 7.0/10
(I reserve the right to weight each category totally arbitrarily!)

The Signal and the Noise — Nate Silver

I love Nate Silver, and not just because we share a birthday! He’s a pretty sharp guy who’s damn good at what he does, and what he does is predict. Silver runs the blog FiveThirtyEight, which famously correctly predicted which way 49/50 states would vote in the 2008 US presidential election. He improved his model, and in 2012 he got all 50. (He’s working hard on 2016, believe me!) He started off in sports statistics around the era of the Moneyball story, and moved into political prediction in the mid-2000s. The Signal and the Noise is about prediction, in various forms. He talks about his own political and sporting predictions, and their successes and failures, but he also talks about the financial crash, gambling, weather forecasting, climate modelling, and more, and in each case he evaluates how each particular field’s prognostication power holds up to scrutiny.

He also talks about his preferred method of prediction: Bayesian inference, a mathematical idea that’s part equation, part philosophy, and part way-of-life. Although most of the chapters in the book aren’t about the sciences, I’d say this book should be almost required reading for anyone working in science, on both the theory and experiment side. It’s shocking how little statistics some scientists (myself included) can get away with knowing, and how little thought we actually put into what our data means. This is a big part of the theme of the book, along with teaching how to distinguish between signal and noise (hence the name). It’s well written, quite technical, and thoroughly detailed, but also full of personal anecdotes and human stories, and it’ll help you see through bullshit and spurious claims from all sorts of places. Definitely check this book out.

Accessible? – – – – – – 7.5/10
Interesting subject? – – 9.5/10
Science content? – – – 8.0/10
Well written? – – – – – 9.0/10
Overall score? – – – – 9.5/10

Smashing Physics — Jon Butterworth

(The book is marketed as Most Wanted Particle in North America.) Now, full disclosure here, Jon Butterworth is the head of the UCL physics department, making him technically my “boss”. But I like his book anyway! Yay! Professor Butterworth is a particle physicist, and one of the “higher ups” at CERN. (You know, that place where they smash the particles in the big ring so Al Gore can invent the internet?) Due to his position in CERN, Professor Butterworth knows all of the insider information from the organisation from what is arguably its most exciting period ever — the completion of the LHC and the search for the Higgs boson. The Higgs boson is a fascinating theoretical object in its own right, but the book isn’t about that, it’s about the human story of the people who worked at CERN during this time.

Professor Butterworth goes through the history of CERN and his personal involvement with it, mostly focusing on the time from the LHC being turned on (and the ensuing media attention) to the Higgs officially being discovered. Aside from some brief tangents into the very basic outline of the physics, which amounts to just enough to explain why they’re doing what they’re doing, the book is mostly about the consequences of letting a bunch of nerds run a multi-billion-Euro, international science experiment. Hilarity ensues!

It’s fascinating stuff, and it’s written in a very light, easy-to-digest tone that I think does a great job of showing what we physicists are like, what our jobs are like, and what our lives are like. A great read.

Accessible? – – – – – – 10/10
Interesting subject? – – 8.5/10
Science content? – – – 6.5/10
Well written? – – – – – 8.5/10
Overall score? – – – – 8.0/10

The Rise of the Robots — Martin Ford

No, it’s not a science fiction book. It’s actually more of an economics book. (So more dismal science than popular science!) Automation is a huge part of our modern lives (I did my MSci project on it, and Ford actually cites some of the same people as my dissertation), and it’s set to become even more prominent as technology progresses.

In a well-written, easy to understand book, Martin Ford takes a look at some of the progress recently made in AI, robotics, computing, and engineering, and assesses how these technologies are going to affect the job market over the next few decades. Simply put: if an AI can do most jobs better than any human, why hire humans at all? And once we’ve got to that stage, what do we do with people who aren’t unemployed, but unemployable? Humans need not apply.

Most people, when presented with this argument, cite historical precedent: there’s been mass shifts in employment in the past due to new technologies, why should now be any different? Automation won’t mean fewer jobs, just different ones. Ford presents what I think is the best, most well-argued case against this assertion and explains why this time it really is different, why, unlike in the past, the new jobs automation will bring won’t be sufficient, and why we should be afraid, be very afraid.

Accessible? – – – – – – 8.0/10
Interesting subject? – – 9.0/10
Science content? – – – 6.5/10
Well written? – – – – – 8.0/10
Overall score? – – – – 8.0/10

So that’s Tom’s summer conference reading list. What’s next? Well I’m going to another conference next week, the last one of the summer to round off conference season. It’s in the exotic, far off locale of… Cambridge (England, not Massachusetts), so I’d better bring some light reading. Luckily, I’ve got just the thing:

A 400-page tome on philosophy and theoretical physics from my favourite popular science author, Sean Carroll! Maybe I’ll review it later, along with some of the other popular science books I read earlier in the year. Until then, thanks for reading!

You Should be Excited About Proxima Centauri b

Artist Impression of the planet (from Wikipedia)

You might have heard the news a few weeks ago that astronomers had discovered a new exoplanet, Proxima Centauri b, and you should be excited about it. Given that a few months previously the space telescope Kepler announced it had discovered over a thousand new exoplanets, you might be curious as to why this particular one merits more excitement than all the others (which also merit a lot of excitement). I’m here to tell you why it does, and why it’s a damn near perfect exoplanet discovery.

An exoplanet is any planet outside of our solar system (so not orbiting our star, the Sun). Until about 25 years ago, none were known to exist. It was entirely possible that our star was the only one in the universe with any planets orbiting it. It took a long time to become confident of their existence, but now we know of the existence of thousands. We also know enough to confidently say that practically every star in the universe probably has at least one planet around it, likely more.

The logical next question is whether any of these planets are habitable, and, indeed, whether any are inhabited. There’s several problems with this line of thought, however. “Habitable” is a very loaded word, with lots of implications about the nature of planets and of life itself. The trouble is, of course, we only know of one inhabited planet in the universe: ours. All life on Earth comes from a common ancestor: LUCA, and so has a lot in common biochemically. Must life evolve the way it has here, or could it look totally different? We need to find examples of truly alien life to find out, but in the meantime our best choice is to find and explore “Earth-like” planets which can host life like ours.

Finding Earth-like exoplanets is difficult, though, even relative to the difficulties of finding exoplanets in general. The methods we use to find exoplanets are more effective the bigger the planet is, meaning that most discovered exoplanets are gas giants many times the size of Earth. Not exactly prime real estate.

From FiveThirtyEight's excellent exoplanet article
From FiveThirtyEight’s excellent exoplanet article

Of course, so far we’ve only talked about looking at exoplanets. But if we’re ever to truly understand alien life, some day we’re going to have to actually go to one of these planets. The problem there, of course, is that space is big. Really big. Not just in the sense that it has big things in it (though that’s certainly true), but in the sense that things in it are really far apart. Travelling at the speed of light, the fastest speed physically possible, 670 million miles per hour, it takes eight minutes to go from the Earth to the Sun, a few hours to go from Earth to Pluto, and four years to reach the closest star to ours. Our fastest spacecraft go at about 38,000 mph, meaning it will take 70,000 years to travel that distance.

So if we ever want to do biological field work on an alien world, we need to find a planet that’s a) potentially habitable, and b) as close as possible.

Proxima Centauri b is both of those things.

It’s almost the luckiest break we could ask for in astrophysics. Proxima Centauri is the closest star to ours (hence the name), at only four light years away (as implied above). Hence the new exoplanet discovered around it has automatically become the closest exoplanet to Earth. So the fact that it’s “potentially habitable” is close to a goddamn miracle.

But what does “potentially habitable” mean in this context? For a start it means its mass is low — between one and three times Earth’s mass. This means it’s probably not gaseous but rocky, like Earth, and probably about the same size as the Earth. More excitingly, though, it’s at the right distance from its host star for liquid water to exist – not too hot, not too cold. (Yes, people do call this the Goldilocks Zone.) There’s not much more we know now, but it’s already ticking a lot of boxes for life as we know it to exist on its surface. Very few planets we know of tick all these boxes. This is why it’s so exciting.

It’s not all great news, however. Whilst it has some of the best odds of hosting life out of all the exoplanets we know, they’re still not good odds. It has a few things working against it. For a start, Proxima Centauri is a red dwarf, meaning it’s smaller and cooler relative to other stars (it’s still about 40,000 times the Earth’s mass). It’s actually so dim that it’s not visible to the naked eye in the night sky. (That’s why its planet was so hard to find, too.)

This means the star’s Goldilocks Zone is much closer to it (you need to stand nearer a cooler flame to feel the same heat), and indeed, our new planet friend is very close to Proxima Centauri.

This is bad because red dwarfs are known to eject violent, high energy x-rays very frequently, meaning the planet is getting big doses of radiation quite frequently. This kind of radiation means its atmosphere would get blasted away into space quite quickly, so odds are the planet doesn’t have any substantial atmosphere. (Not to mention the bad stuff that radiation is known to do to life on Earth.) Water can only exist as a liquid when the atmospheric pressure around it is sufficiently high, so the odds of a surface ocean are probably quite low.

We always see the same side of the Moon, even though it does rotate. That’s because it’s tidally locked to Earth (as we are to it). The same is probably true of Proxima Centauri and its planet: one side of the planet will always be facing the star. This can cause massive temperature differences on the different sides of the planet, meaning it probably only has water-friendly temperatures in a literal “twilight zone” in the middle of the planet.

Time and tide: Wikipedia illustration of tidal locking

So ok, it’s not looking great for life. But could we at least go and check? Can we ever hope to visit the planet? Well, surprisingly, despite the aforementioned vastness of space, there already is a plan to send a probe to the star within a human lifetime. Announced earlier this year, Breakthrough Starshot is an ambitious plan to accelerate microchip-sized probes to near light speed, meaning they could reach the star in a few decades, scan it, and send data back. It requires some, shall we say, “engineering innovations” (to put it very mildly) to work, but it’s theoretically plausible, and could easily be launched in a few decades. I fully believe I will see the first grainy, low-res images of this planet before I die, and given the technological challenges involved in that, it’s really, really exciting.

New Year’s resolution: Our best view of Pluto before and after we sent a probe to study it

There’s so much more to say on this story. Exoplanetary research is a very new field. I expect this year’s physics Nobel Prize to go to something exoplanet related, and that’s only the beginning of what we’re going to discover about the distant worlds out there in the heavens. Closer to home, my supervisor and research group are involved in exoplanet research. We’re even involved in a mission to launch a small exoplanet-hunting satellite, TWINKLE, ourselves. Check it out!

Don’t ask us what TWINKLE stands for…

Are we alone in the cosmos? It’s arguably the most profound unanswered question in science. The day we find out is getting closer all the time.