Random Musings on the Stuff of Science and the Science of Stuff

“The nation that controls magnetism will control the universe”*

By Cheryl R Stewart
November 17th, 2011

Many of you may have heard of the cartoon character Dick Tracy.  Chester Gould created the character and from 1931 until 1977 it ran in a large number of daily newspapers and was one of the most popular cartoon strips ever drawn.  (Sadly, It won’t be long before one will need to remind readers what a newspaper is as well as who Dick Tracy was).  Dick Tracy was a detective and crime fighter who used advanced technology (for his day) to keep the world safe. Chester Gould was quite visionary and anticipated many technologies that would later become reality such as the 2-way wrist radio (the cell phone), atomic light (laser), portable surveillance camera, closed circuit TV for police lineups, electronic telephone number tracking (caller ID) and magnetic space propulsion.  It was this last invention that gave rise to the famous quote in the title. Moore’s Law and the exponential growth in semiconductor technology is undoubtedly known to you all but there has been a similar growth in storage density in magnetic materials with a halving in cost every 15 months.  Thus the trends in magnetic storage are every bit as fast as Moore’s Law and, in fact, if they had not... More

Lighter Than Air, Better than Gas

By Cheryl R Stewart
November 10th, 2011

Gasoline is pretty amazing stuff.  It has a high energy density, can be manufactured and delivered for less than the cost per ounce of bottled water and has allowed a transportation infrastructure to be developed that has reshaped the face of America.  It has changed how and where we live and work.  If it weren’t for the minor issues that we are rapidly running out of the stuff and that burning it trashes our planet, we would be good to go. A lot of thought and research has gone into thinking about what we can replace it with for transportation.  While battery powered vehicles get a lot of press, there are some pretty fundamental limits that will restrict their use.  Basically, the problem is that batteries are mostly a terrible way to store energy.  In a world with Moore’s Law telling us that semiconductors and computers get a factor of two better every 18-24 months, progress in batteries pokes along at a pretty leisurely pace.  Your great-grandfather would recognize a “D” cell and know what it does but would have no clue about what your IPhone is. So alternatives are being actively worked.  One serious contender is what is called the... More

Water, Water, Everywhere, Nor any Drop to Drink

By Cheryl R Stewart
November 3rd, 2011

Those of us living in the developed world take clean water for granted.  If you are in Boston or NY or almost anywhere else in the US, if you wanted a glass of clean water all you would need to do is get up, walk a few steps and drink your fill.  Most of us would view this as a pretty unremarkable thing to do.  Unfortunately, to many people around the world, this simple, commonplace act is an impossible dream. In many parts of the world, enough clean drinking water is an unimaginable luxury. Estimates are that water borne illnesses kill 3 million people a year and make many more ill.  The toll among babies and children is particularly brutal as they are more at risk than adults.  In a lot of places in the world, someone’s source of drinking water is downstream from someone else’s toilet.  A clean, simple and inexpensive way to purify water would save the lives of millions of children per year. If you think of all the things one could do to alleviate misery in the under-developed world, providing enough clean water would be pretty close to the top of the list. In the US we... More

The Wonder of it All

By Cheryl R Stewart
October 27th, 2011

Solid State Physics is one of the great human intellectual achievements of the late twentieth century.  Since roughly the end of the Second World War until the present, there has been put into place a body of science that provides a predictive understanding of extremely complicated chunks of matter.  For those of us who have a role (small) in that enterprise, it is sometimes worthwhile to take a step back and admire the entire edifice instead focusing on just the specific brick we are working on. While it is easy to take our current level of understanding for granted, it is not at all obvious that we should have ever been able to understand anything about the solid state.  A typical piece of matter, say a chunk of iron, has in it a vast number of atoms (~1024) as well as a more vast number of electrons (~1025), some of which are attached to the atoms and some are which are whizzing about inside the metal.  The electrons have a charge and a magnetic spin, the atoms have a charge and a spin, thermal effects shake everything up and there are interactions that occur on many different length scales.  A typical... More

If You Can’t Take the Heat: Make a Better Frying Pan

By Cheryl R Stewart
October 20th, 2011

Despite the fact that we should all know better, the amount of electricity we use in the US continues to grow* at a steady clip.  I guess it’s tough to put down that Xbox.  If we don’t want Albany, NY to become ocean front property, we need to figure out how to create the electricity we need much more cleanly and efficiently. An important technology for generating electricity from natural gas is the advanced gas turbine.  Using natural gas produces roughly 30% less carbon dioxide than oil and 45% less than coal.  Natural gas is the cleanest hydrocarbon fuel we can use to create electricity and the US has vast supplies of it which, if used carefully, should last us for at least a hundred years or so, well beyond the time when I’ll go to that great lab in the sky. So given the need to bridge the gap from where we are today to much lower carbon footprint solutions that will exist at some point but which aren’t ready yet, natural gas is a crucial part of the US energy roadmap for the foreseeable future. Because of the laws of thermodynamics, gas turbines run more efficiently the hotter they get... More