Category: Physics

JF Ptak Science Books  Post 2681

Superman was (is?) as fast as .00005% of the speed of light, or thereabouts, if you gave him the benefit of the speeding bullet being a 50-cal round muzzle velocity. On the one hand, it is fast; on the other, well, not so. 

That is what sort-of attracted me to this present pamphlet. I determined to simply scan the thing (James Jackson, Tableau de Diverses Vitesses exprimes en metres par seconde¹, published in Paris in 1885)  for a quick blog post “On How Fast Stuff Is and Isn’t”. The slowest on the list was the “Corissance du bambou”/the growth of bamboo, which is actually a quickly-growing thing but not so when in comparison to how many meters it grows per second.  And that’s what this is, a little 8-page pamphlet listing about 350 things and how fast they are, all calculated in meters/second. The selections are actually pretty interesting in and of themselves.  So first to last, where I find several different calculations for the speed of light…and then something else, faster than the speed of light.  

The last entry was this: “courant electrique provenant de la decharge d’une bouteille de Leyde dans un fil de cuivre de 0^m,0017 de diametre” (“electric current from the discharge of a Leyden bottle into a copper wire of 1/16th of an inch”), with a velocity of 463,000,000 metres/second. No doubt Jackson is just talking about electron flow, which is about 1% of the velocity of the speed of light c along a wire or so (and far less along the wires in your kitchen appliances) while the flow of electromagnetic energy in a vacuum is exactly c–and what he is writing about here is warp 1.2 or a 50% increase in the velocity of electricity over light, when electricity and light are basically the same thing. I just don’t know what he is talking about.

The Scientific American Supplement posts a notice of this bit, quoting the American Machinist in its review of Jackson’s work, and which also takes care to mention the faster-than-light speed as “the greatest rapidity so far measured”:

“The American Machinist extracts from a contemporary a gamut of speeds per second beginning with that of the snail oil is half an inch and ending with the following Electric current on telegraph wires 7,000 miles induction current 11,040 miles electric current in copper wire armatures 21,000 miles light 180,000 miles discharge of a Leyden bottle through copper wire 1 16 inch in diameter 277,100 miles This last is the greatest rapidity so far measured. These figures might have more weight and more interest if the methods of calculating them or the authorities had also been given.”  Scientific American: Supplement, Volumes 43-44, July 31, 1897 p 17997. 

Remember that we’re dealing with c twenty years before Einstein’s seminal year, when the fastest speed obtainable by anything was that of  light and which was considered to be infinite since in space there would be nothing to get in its way, at least according to Johannes Kepler (1571-1630), who imagined that no matter where the originating point of the light source was it would be seen instantaneously from any other point, no matter the location so long as there were no obstacles.  Estimates of light’s finite speed were proposed by scientists who were born at about the time that Kepler died by Ole Roemer and the everything-man, Christiaan Huygens (who estimated the speed of light at very near the present determination, which was 220k km/s. None of these names appears on Jackson’s list, though more recent additions like (Marie Alfred) Cornu (1878 using the not-named-here Fizeau instrument), (A.A.) Michelson (1879), Young, and Forbes (as in James Young and George Forbes in 1882) do. 

Anyway the faster-than-light speed Jackson was referring to was for electricity, and no doubt came from the experiments in 1834 by Charles Wheatstone (thanks for the push, Dave Wenner!)

I should make a note within this note of the work of Camille Flammarion (1842-1925), a very provocative and imaginative writer, who produced a small novel called Lumen (1887) in which the main character/souls move through the universe at what must be speeds way beyond the speed of light. His work in general looks like a collection of sci-religio-fiction, with creative writing on time travel (or observation, or viewer, I’m not sure), teeming extra-terrestrial life, transmigration of souls, and so on, filling and flying through the vastness of time and space, and I think collapsing the idea of time itself.  (“Lumen” is a recently-dead ET soul that dialogues with Questor, and they wind up moving through the universe at warp speed.)  So, there’s that.

Anyway this sort of post calls for a lot more reading, which I’m sorry to say I haven’t done–I just don’t know yet how fast the fastest things were believed to be through the history of science. At least this post gets the ball rolling, if only for me.  

Notes:

1.  I found seven copies of this 1885 printing in WorldCat/OCLC, the holdings a stellar pedigree (LC, NYPL, Yale, Harvard, U Wisconsin/Madison, Oxford).

 

JF Ptak Science Books  Quick Post

So, while reading in the Annals of Philosophy–an interesting and curious journal with some important original contributions and a large selection of other interesting papers previously printed elsewhere and which was later absorbed by the more-prestigious Philosophical Magazine–for 1824, after finishing trying to figure out what Gay-Lussac was doing with lightning conductors, I stumbled my way through the journal’s monthly section of “scientific notices”.  The “notices” are usually very brief and give enough info so that the reader can make their way to the original source to read the report in-full.  This is how I came upon the great J.J. Berzelius and this note on the taste of positive and negative electricity, which I admit I’ve never thought of before–I was curious about what the “distinction” would be, and then was surprised by what he wrote:

By the way, it was determined in 1822 by some governing committee in France that all large churches in France needed to be protected by lightning conductors–the use of lightning conductors was established during Ben Franklin’s time. This evidently became an issue following a particularly bad bit of weather during which numerous churches were damaged, including the Rouen cathedral. Gay-Lussac notes elsewhere that the fear of thunder makes no sense, because the lightning event has already occurred, and that nothing can happen at this point. He points out that people struck by lightning never hear it coming, and have no idea what happened to them–small is that comfort.

 

JF Ptak Science Books   Quick Post

Here’s an interesting combination of sweat and electricity–an enormous electrical device that was on display in an exhibit of “natural magic” at the Colosseum in Regent’s Park in 1839.  The large disk that the two guys are turning is actually larger in real life, being 7′ in diameter, the conductor being varnished copper, and the conducting balls being gilded–it must have been a very shiny experience, especially when they generated their electric spark.  In 1839 this was the largest electrical generating device in the world.  (I have a tiny version of that device here, something made out of old records coated with copper and found ball glasses acting as Leyden jars, all painted and varnished, the work of an 8 year old in 1925 who went on to a career in astronomy and became the most celebrated eclipse follower in the mid 20th century.)

This monster is made just 39 years after Volta’s first battery was made,  and not long after Oersted generated the first magnetic field from an electric current in 1820, the same year as Ampere’s solenoid. There were many quick and brilliant development from then to 1839 (also the year in which Daguerre perfected his collaborative work with Niepce to produce the photographic camera), not the least of which was the  Davidson’s creation of the first electric motor car/land locomotive, again in that same full year of 1839:

[Image source: A. du Moncel Electricity as a Motive Power, 1883, page 55, full text from the Internet Archive, here.]

 

JF Ptak Science Books   Post 2458

It really is a rare thing to open a book and find it full of significant contributions by numerous people occurring in situ as it were–not an intentional collection of greats, but a “serendipitous one.  In this case the find occurred in one bound volume of the American Physical Society’s Review of Modern Physics–a single volume containing two years of papers for 1945 and 1946. I’ve seen this a number of times–as with bound volumes for The Physical Review for 1932, and 1939 and 1948, for example–and it is always a pleasure to watch the great epic of those years roll out as you leaf your way through the volume.  

And so it happens with volume 17 and 18 of the Reviews¹, the greatest interest in this volume is no doubt the multiple blockbuster of contributors for the commemoration of Niels Bohr’s birthday, in Volume 17/2, April-July 1945, pp 97-350, “In Commemoration of the Sixtieth Birthday of Niels Bohr, October Seventh, 1945”. The field is full of the major names (and Nobel Prize recipients) of physics in the 20^th century. These include Bloch, Born, Chandrasekhar, Dirac, Einstein, Feynman, Gamow, Goudsmit, Heitler, Hevesy, London, Meitner, Pauli, Rabi, Van Vleck, Weisskopf, Wheeler, and others, a full-ish list of the papers is included below. (The Wheeler-Feynman paper is significant on its own and highly cited.)

• This volume is available for purchase at the blog’s bookstore, here.

JF Ptak Science Books   Post 2433

James Chadwick’s introduction of the existence of the neutron made a “sly” entry into the general/popular scientific world–if such things could have personalities, then it would certainly be “humble”.  Except of course “humble” has no place in this vocabulary, except for instance like this, interpreting the poetry of the moment. Chadwiock’s “Possible Existence of a Neutron” appeared in Nature, 27 February 1932. volume 129,   the revolutionary contribution appearing as a Letter to the Editor, in 1.25 columns, on page 312 of this issue of the journal. And in the “tradition” of the Alpher-Bethe-Gamow paper (the great paper on the Big Bang, appearing on April 1st 1948 in the Physical Review), it is another of very many instances of a major announcement being made as a “simple” letter to the editor. (Well, in the case of scientific letters, this is really just a shorter, quicker-to-publication avenue to publication, and not much at all like a letter-to-the-editor of the NYT. Still, the description has a nice ring to it.)  This was the description of the neutron made after only about two weeks of experimentation.

“In 1932, Chadwick made a fundamental discovery in the domain of nuclear science: he proved the existence ofneutrons – elementary particles devoid of any electrical charge. In contrast with the helium nuclei (alpha rays) which are charged, and therefore repelled by the considerable electrical forces present in the nuclei of heavy atoms, this new tool in atomic disintegration need not overcome any electric barrier and is capable of penetrating and splitting the nuclei of even the heaviest elements. Chadwick in this way prepared the way towards the fission of uranium 235 and towards the creation of the atomic bomb.”–NobelPrize.org

His next paper¹–and perhaps the more famous of the two–appeared a few months later in May and contained the proof of the existence of the neutron, and was an epochal achievement int he understanding of the nucleus.

For this epoch-making discovery he was awarded the Hughes Medal of the Royal Society in 1932, and then the Nobel Prize for Physics in 1935. I think he may be the only recipient of the award who was also at one time a POW. (1914-1918 in Chadwick’s case, going from there to a Ph.D. at Cambridge in 1921 and then to Rutherford’s assistant shortly thereafter.)

Notes:

1. Chadwick, J. (1932). “The Existence of a Neutron”. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences136 (830): 692. Another paper appeared int he next year, (1933). “Bakerian Lecture. The Neutron”. Proceedings of the Royal Society A: Mathematical, Physical and Engineering

JF Ptak Science Books   Post 2425

Here’s an interesting set of delightful photographs (and one painting) of some great scientists as babies and kids.  Many of them are obvious, I think, and you can see their developed and mature faces in themselves from very early on.  For example in the first photo is Niels Bohr, his arched eyebrows and halfways-kinda-grin already there at age 4 or 5.  Paul Dirac is gorgeous as a kid and he keeps those eyes throughout his life. The Einstein is an uncommon images, plucking him from a class photo–I guess you can see him in there, somewhere, though it isn’t as Einstein-y as some of the other early photos of him where his eyes are just unmistakable.  Feynman looks like Feynman, sly and smart-as-hell; and the impish and sparkling Turing seems as he would be decades on.  On the other hand the fabulous Kurt Goedel baby could be almost anyone–though I have to say it isn’t often you see photos with the baby’s arm raised.  

Four of these came from a very nice post on exactly this topic at Kuriositas: (http://www.kuriositas.com/2011/10/famous-scientists-as-children.html) though even at the outset there are more science babies and kids together here than I can find elsewhere.  

Niels Bohr, 1890, age about 5. Source: http://www.nbi.ku.dk/english/www/niels/bohr/barndom/