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I have a rule: if I see an article by Frank Wilczek, I read it. Wilczek is a particle physicist and Nobel Prize Laureate, and recently wrote on “Why Does the Higgs Particle Matter?” for Big Questions Online:

The discovery of the Higgs particle is, first and foremost, a ringing affirmation of fundamental harmony between Mind and Matter.  Mind, in the form of human thought, was able to predict the existence of a qualitatively new form of Matter before ever having encountered it, based on esthetic preference for beautiful equations.

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A nice talk from Jeff Shallit from Recursivity on numerology. I’m going to forward it to a guy who keeps emailing me about his “Final Formula” of physics:

\hbar c = \sqrt{10} \times 10^{-26}

which has the same problem with units that Shallit’s marvellous Washington Monument example does.

That said, there have been a few episodes in physics where something that looks alarmingly like numerology proved successful, such as Gell-Mann’s 8-fold way. Murray Gell-Mann plotted mesons and spin-1/2 baryons on a plot with charge on a horizontal axis and strangeness on the diagonal. The particles formed an octagon with two particles at the centre. He also plotted the  spin-3/2 baryons, which formed a triangle, but with the apex missing. Gell-Mann predicted the existence of the particle that would complete the triangle, together with its strangeness, charge and mass. Two years later, it was discovered.

Is this really numerology? I’m not familiar with Eddington’s argument, but my suspicion is that the difference is in predictive power. Gell-Mann predicted the existence of a particle, its properties and was ultimately led to the quark model, whereas the zero-predictive-power of Eddington’s ideas were displayed by his easy switch from pulling 136 out of a mathematical hat to producing 137.

The moral of the story seems to a combination of the following:

  • While successful physical theories can predict relationships between physical quantities that would otherwise appear to be coincidences, searching for such coincidences in the absence of a deeper physical theory is not a good way to discover the laws of nature.
  • The deeper we go into the laws of nature, the more remarkable simplicity we uncover. The applicability of group theory and symmetry to particle physics is a good illustration of this.
  • The power of science comes not from its ability to make assumptions about nature, but the ability to test those assumptions and discard those that fail. That’s why this quote from Mark Twain about “wholesale returns of conjecture out of such a trifling investment of fact” only tells half the story of science. In particular, one must keep an eye on the relationship between the number of free parameters and the number of data points, so that we can tell the difference between prediction (where the data tests the model) and curve-fitting (where the data creates the model).

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For more superb public speaking advice, see Teddy Wayne’s article for the New York Times.

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How much does the altitude at which a cricket (or baseball) match is played affect the flight of the ball? If you’re only interested in the answer to that question, then skip ahead. But there is a reason I am particularly interested in this question, and it has to do with a freakish cricket match played in 2006.

Every sport has its fables and epics, and nothing attracts a story like an outlier. In statistics, an outlier is an event that is way out on its own, deviating significantly from the rest of the population. In cricket, for example, the primary statistic that measures how good a batter is is the batting average, defined as the average number of runs per dismissal. The details aren’t required here; it will suffice to say that an average of above 50 in test cricket marks out one of the greats. Below (top) is a plot of the batting averages of all those who have played test cricket.

We see few players with an average greater than 50, and even fewer above 60. And then comes the outlier, way off to the right – Donald Bradman, with a career average of 99.94. His other career statistics are similarly off-the-scale. The premier achievement for a batter in a match is to score a hundred runs in a single innings, a century. Bradman did it 29 times in his career of 80 innings. Of the 7 batters who have scored as many or more centuries, all required at least twice as many innings. Cricket is one of the few sports in which the question “who was the greatest?” attracts little debate.

Cricket has also seen freakish matches. (more…)

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(Via Luke Muehlhauser).

Oh dear. I know fundamental physics can be difficult, but this is ridiculous.

Time magazine recently posted 30 nominations for its ever-popular “Person of the Year” award. Tucked in between President Barack Obama and the Korean rapper Psy is an unlikely candidate for the “Person of the Year”—a subatomic particle. As Scientific American readers are well aware, physicists at the Large Hadron Collider announced this summer that they had found something that looks much like long-elusive Higgs boson, causing a brief but wondrous worldwide bout of Higgsteria.

Under ordinary circumstances, we would be all for the elevation of the Higgs to “Person of the Year” status, if only to further honor the heroic efforts of thousands of scientists and engineers who made the discovery possible (more on that below). But Time’s nomination threatens to do more harm than good. Every single sentence in Time’s nomination contains at least one serious error. The magazine scores a perfect five for five. …

Sentence 4: But it was not until last summer that a team of researchers at Europe’s Large Hadron Collider — Rolf Heuer, Joseph Incandela and Fabiola Gianotti — at last sealed the deal and in so doing finally fully confirmed Einstein’s general theory of relativity.

Error: Where to begin? Let’s start with Einstein. I honestly have no idea why the author would make any connection between the Higgs and general relativity. None! Because there is none. Einstein did teach us that energy and mass are two sides of the same coin (and that insight is a consequence of his special, not general, theory of relativity), but this teaching works at cross purposes to the author’s repeated assertions that the Higgs somehow transforms energy into matter.

How does a science writer with 20 years experience make this many errors? Laziness? Too many over-hyped press releases? There are thousands of scientists he could have had check those five sentences.

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I happened across the following mathematical titbit, which I will set as a question to the reader. Let,

\mu = (\sqrt{5} + 2)^{1/3}-(\sqrt{5} - 2)^{1/3}      (1)

You are required to prove that

\mu = 1.

Striking, no? Obviously, sticking it into a calculator doesn’t count. I know a rather indirect way, which unfortunately involves the phrase “by inspection”. I’ll share it with you below the fold. There must be a nicer way! (more…)

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Comics!

I’m surprised I haven’t posted an xkcd comic before, but this was a good one!

And one more from SMBC:

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We’re the leaders of an alien race. We’re planning to invade and exterminate/subjugate humankind. Here is a good plan for invading Earth, as detailed in the movie “Independence Day”.

  • Have our central mothership parked well away from Earth. Humans don’t really have weapons to attack targets in space. Have a large (in the millions) invasion force on standby in the mothership.
  • Given Earth’s well-spread military and civilian targets, bring along 36 smaller (but still city-sized) ships to send to strategic locations. Arm these ships with one, massive, city-levelling weapon. Make sure ships can withstand nuclear weapons. Have the mothership power a defensive shield around each smaller ship.
  • Disguise ships as strange atmospheric phenomena as they get into position. Don’t show aggression too early.
  • Fire main weapon on all ships simultaneously.
  • Should humans attempt to fight back with fighter jets, send our fighters to engage. We don’t really need to do this, but decimating their feeble air force will underscore our obvious technological superiority.
  • Continue using smaller ships to destroy cities and military targets. Once human population and military largely decimated, send in invasion force from mothership.

That is a pretty good plan. In fact, it’s so good that the aliens would have to do something really stupid, or the humans something utterly miraculous, for the plan to fail. (Spoiler alert) That miraculous thing turns out to be Jeff Goldblum, who is able to plug his laptop into the alien spaceship and – without as much as a text editor in sight – program a computer virus able to disable the shields of the entire fleet. That, and the fact that the main weapon of the smaller ships is prone to backfire, and the Earth is saved.

Now let’s go over the plan devised by the aliens in “The Avengers”.

  • Open a single portal from our planet to Earth, over New York City.
  • First, send through about 100 soldiers on small flying bikes. No need for a fully-enclosed fighter. Equip these bikes with a weapon capable of destroying a small sedan. Instruct the soldiers to fire at civilians and civilian traffic.
  • Give the soldiers a spear capable of firing a laser beam. Encourage soldiers to eschew said laser beam in favour of hand-to-hand combat. Laser beams are expensive.
  • Follow up with a large flying creature. Give the creature a thick armour, but no weapon apart from its bulk and mouth. It will fly alongside high-rise buildings, breaking windows and disfiguring the architecture with its fins. It will also serve as troop transports. It holds around 100 soldiers. Configure creature to shoot soldiers onto the outside of the human skyscrapers, because we’re pretty sure that’s where human beings hang out.
  • When supervillain Loki commands: “Send the rest!”, send through all the creatures we have. We seem to have about 10. Maybe 20. That’s an invasion force of about 2000 soldiers. Our soldiers can be taken down with a bow and arrow, so hopefully the (7 billion) humans don’t have any of those. Or handguns. Or know how to karate chop the back of our necks.
  • The bikes and flying creatures can travel at about 100 km/h. Once we have captured New York, proceed to Beijing. Hopefully the other independent sovereign nations of Earth will not have coordinated a military response in the 4-5 days it will take us to get there.
  • Park our mothership just on the other side of the portal. Don’t worry about anything coming back through the portal. The mothership shouldn’t need shields of any kind, or the ability to shoot down incoming missiles.
  • We possess no weapons remotely comparable to a nuclear weapon. We have no shields capable of withstanding a nuclear blast. I confidently predict that there is no need to worry about this at all.
  • Have all soldiers, bikes and creatures remotely powered by the mothership. If the mothership goes down, or if the portal is temporarily closed, our entire invasion army will drop like a sack of potatoes. All the more reason not to worry about defending our end of the portal or the mothership itself.
That, obviously, is a pretty feeble plan. The movie hints that the invading force has underestimated the humans. That’s a major lack of intelligence, especially from Loki, who has witnessed both US defence research facilities and the S.H.I.E.L.D. flying fortress.

The writers of alien invasion movies face a massive problem: almost certainly, an alien invasion would be a massacre, a relatively minor extermination program. Wars between human beings are only close because our technology has progressed in step. An alien invasion would be like the modern American military attacking ancient Egypt. There isn’t any dramatic tension. To make an interesting plot, the aliens must be rather stupid (like overlooking the problem of Earth’s microorganisms and diseases), or cocky, or drastically misinformed, or else the humans must be extremely lucky and/or well-equipped.

That said, I very much enjoyed The Avengers, and add my personal approval to the other 97% of critics. I quite liked Independence Day as well. I suppose the only alien invasion stories worth making into a movie are the ones where we, somehow, win.

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SMBC!

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A few months ago, I wrote two posts on Lawrence Krauss’ take on the question of why is there something rather than nothing. In the meantime, he has written a book on the subject. I don’t need to review the book, because David Albert has done it for me in the New York Times. Here’s a highlight:

The fact that some arrangements of fields happen to correspond to the existence of particles and some don’t is not a whit more mysterious than the fact that some of the possible arrangements of my fingers happen to correspond to the existence of a fist and some don’t. And the fact that particles can pop in and out of existence, over time, as those fields rearrange themselves, is not a whit more mysterious than the fact that fists can pop in and out of existence, over time, as my fingers rearrange themselves. And none of these poppings — if you look at them aright — amount to anything even remotely in the neighborhood of a creation from nothing.

Even worse is Dawkins’ afterword to Krauss’ book: “Even the last remaining trump card of the theologian, ‘Why is there something rather than nothing?,’ shrivels up before your eyes as you read these pages. If ‘On the Origin of Species’ was biology’s deadliest blow to super­naturalism, we may come to see ‘A Universe From Nothing’ as the equivalent from cosmology. The title means exactly what it says. And what it says is ­devastating.” Pathetic, desperate nonsense. By his own admission, Krauss isn’t answering the question “why is there something rather than nothing?”; he is using equivocation to substitute an unrelated scientific question “why are there particles rather than the quantum vacuum?” and then announcing victory over the philosophers. What it says is not devastating. It is sophomorically irrelevant.

Via Ted Poston.

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