science

What’s all this fuss about having alternatives?

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I don’t know what all the fuss is about “alternative facts.” Why, we scientists use them all the time! For example, because of my political views, I teach physics students that gravity pulls down. That’s why the students I teach, when they go on to be engineers, put wheels on the bottom corners of cars, … Read more

Why Theories Don’t Go Into Hospitals

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I’m always amused at how very reasonable remarks so often generate attacks from unreasonable people.  I wrote a perfectly ordinary post about what one does and doesn’t learn from LHCb’s important new measurement at the Large Hadron Collider [LHC] (and in fact I overstated the significance of the result — more on that later), and somehow I touched off a mini-firestorm.  Well, that just indicates how essential it is to have calm people expressing sensible points of view.  When people become so politicized that they can’t distinguish propaganda from science, that’s not good.

Forget supersymmetry — because none of my remarks have anything to do with this theory in particular, and the theory doesn’t deserve the excessive attention it’s getting.  Take any theory: call it Theory X.  Extra dimensions; compositeness of quarks and leptons; non-commutative spacetime; grand unification; your-theory-here.  The idea behind theory X may be very clever, but as always, there are many variants of theory X, because an idea is almost never precise enough to permit a unique realization.  Each variant makes definite predictions, but keep in mind that detailed experimental predictions may very well differ greatly from variant to variant.

Now, here is a logical fact:  one of two options is true.

  • Option A: One variant of theory X is “correct” (its predictions agree with nature) while all other variants are “wrong” (disagree with nature)
  • Option B: All variants of theory X are wrong.

Nature is what it is; there are no other options (and this is not the place for a discussion about this basic scientific assumption, so pace, please, philosophers.). [More precisely about option A: the space of variants is continuous, so the correct statement is that an arbitrary small region in this space is correct; you can put in the correct calculus vocabulary as you like.  I’ll stick with the imprecise language for brevity.]

For either option, as more and more data is collected, more and more variants of theory X will become “dead” — excluded because of a disagreement with data.  Therefore — obviously! — a reduction in the number of live (i.e. unexcluded) models always takes place over time.  And this has absolutely no bearing on whether, at the end, all variants of X will be dead, or one (or perhaps several very similar ones) are still alive.

And thus it makes absolutely no sense to describe, as a “blow to theory X” — in particular, to the idea behind theory X — a measurement that excludes (“kills”) even a big fraction, but not virtually all, of the variants of theory X.  It’s certainly a blow to those variants; in fact, it is a fatal blow for them.  But it does nothing to distinguish between Option A and Option B.  It only tells us that if Option A is true, the variant of X that will be alive at the end is not among the ones that have just been killed.

This isn’t rocket science, folks.  It’s logic.  [Well – As a commenter points out, it’s  not “logic” in the strictest sense; but it is basic scientific reasoning.] And if we take theory X to be the Standard Model itself, I’ve just described its history.

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Sandy: Amazing. Science: Amazing.

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My neighborhood of New York City may remain without power for a few more days, but fortunately visible signs of damage are limited — none of the widespread destruction found along the immediate coast of the city and of nearby communities, where the sea rose and swallowed up land that had not seen salt water in many decades, even centuries.  Many trees are down, and countless houses and businesses are wiped out by the sea’s wrath, even entire beach communities. The numbers of lost homes are surely in the thousands, if not more, with 100 houses alone destroyed in a runaway fire in the neighborhood of Breezy Point, cut off from firefighters by the storm’s high water.

Unfortunately, many people along the coast, lulled into complacency by the fact that last year’s Tropical Storm (formerly Hurricane) Irene was a bit less furious along the coast than was forecast, decided not to evacuate. Unfortunately indeed, because the forecast for Hurricane Sandy was worse than for Irene, and this time, there was no lucky break to make the reality of the storm significantly less severe than the worst-case prediction.  I myself know of households who decided to evacuate at the last minute and almost didn’t make it out alive, and others who rode out the storm and found themselves in considerable danger. That so many people remained in harm’s way required “first responders”, as they are termed here, mainly members of the police and fire departments, to make many rescues, quite a few of which wouldn’t have been necessary had people heeded the warnings. For risking their lives to save so many others, the first responders are widely and justifiably hailed as heroes.

Also deserving of high praise, in my view, are some of the leading politicians and other civic leaders in our region’s states and cities.  There are quite of few of them whom I don’t agree with politically and whom I personally don’t like very much, but on the whole they all seem very smart.   And in this case they understood the risks, took them seriously, and made prudent decisions to order evacuations of areas in danger and to protect public property.  They deserve a lot of credit for their non-nonsense approach.

But I feel that there’s an important story that the press is almost ignoring.  There’s another group of people, little-mentioned in the media, who probably saved more lives and property than anyone else.  I refer to the experts at the National Hurricane Center (NHC), and more generally the various branches of the National Weather Service (NWS) and its parent, the National Oceanic and Atmospheric Administration (NOAA).

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