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As a child, I read Friday by Robert A Heinlein, which portrayed a future in which energy needs are addressed by energy storage devices called "Shipstones", which are described as a way to pack more kilowatt-hours into a smaller space and a smaller mass than any other engineer had ever dreamed of. To call it an…
Behind every man now alive stand thirty ghosts, for that is the ratio by which the dead outnumber the living. Since the dawn of time, roughly a hundred billion human beings have walked the planet Earth. Now this is an interesting number, for by a curious coincidence there are approximately a hundred billion stars in…
We recognize in the concept of heat which appears here a similarity to other physical concepts. Heat is, according to our view, a substance, such as mass in mechanics. Its quantity may change or not, like money put aside in a safe or spent. The amount of money in a safe will remain unchanged so long as the safe…
Our sense of touch tells us quite definitely that one body is hot and another cold. But this is a purely quali- tative criterion, not sufficient for a quantitative descrip- tion and sometimes even ambiguous. This is shown by a well-known experiment: we have three vessels con- taining, respectively, cold, warm and hot…
Now we have comprehended and peeled off the layers of petals which disclosed not only that physical energy is conserved but also that it is ever increasingly deposited as a fossil-fuel savings account aboard our Spaceship Earth through photosynthesis and progressive, complex, topsoil fossilization buried ever deeper…
Plants and animals are separated by about 1.5 billion years of evolutionary history. They have evolved their multicellular organization independently but using the same initial tool kit the set of genes inherited from their common unicellular eucaryotic ancestor. Most of the contrasts in their developmental strategies…
...build a round sunshield of lunatic aluminum, very thin material, only 50 grams per square meter and yet still totaling 3 x 1013 kilograms, the largest thing ever built by humans. Concentric strips give the sunshield flexibility and allow it to tack up into the solar wind to hold its position at the L1 point, where…
The sun is always just about to rise. Mercury rotates so slowly that you can walk fast enough over its rocky surface to stay ahead of the dawn; and so many people do. Many have made this a way of life. They walk roughly westward, staying always ahead of the stupendous day. Some of them hurry from location to location…
In the midst of the decline of Greece, Athens, which, in the days of its power, had honoured philosophy and letters, owed to them, in its turn, the preserving for a longer period some remains of its ancient splendour. In its tribune, indeed, the destinies of Greece and Asia were no longer decided; it was, however, in…
This flat conceptioning is manifest right up to the present in such every¬ day expressions as "the wide, wide world" and "the four comers of the Earth." As mentioned before, "up" and "down" are the parallel perpendicu¬ lars impinging upon this flat-out world. Only a flat-out world could have a Heaven to which to…
Environment-controlling buildings gain or lose their energy as "heat o cool" only through their containing surfaces. Spheres contain the most vololume with the least surface—i.e., have the least possible surface-to-volume ratio. Every time we double the diameter of a spherical structure, we in¬ crease its contained…
Once the matter created by the Big Bang cooled sufficiently, the universe consisted of a vast cloud of hydrogen atom consisting of a single proton surrounded by a single electron—along with a smattering of slightly heavier elements, including helium (with two protons) and lithium (with three). The universe at that…
The power of man to do work—one man-power—is, in its purely physical sense, now an insignificant accomplishment, and could only again justify his existence if other sources of power failed. ... Curious persons in cloisteral seclusion are experimenting with new sources of energy, which, if ever harnessed, would make…
The first thing the reasonable man must do is to be content with a very little knowledge and a very great deal of ignorance. The second thing he must do is to make the utmost possible use of the knowledge he has and not waste his energy crying for the moon. The third thing he must do is try and see clearly where his…
A mathematician who can only generalise is like a monkey who can only climb UP a tree. ... And a mathematician who can only specialise is like a monkey who can only climb DOWN a tree. In fact neither the up monkey nor the down monkey is a viable creature. A real monkey must find food and escape his enemies and so must…
Life is order, death is disorder. A fundamental law of Nature states that spontaneous chemical changes in the universe tend toward chaos. But life has, during milliards of years of evolution, seemingly contradicted this law. With the aid of energy derived from the sun it has built up the most complicated systems to be…
…it ought to be remembered that there is nothing more difficult to take in hand, more perilous to conduct, or more uncertain in its success, than to take the lead in the introduction of a new order of things. Because the innovator has for enemies all those who have done well under the old conditions, and lukewarm…
It is the destiny of wine to be drunk, and it is the destiny of glucose to be oxidized. But it was not oxidized immediately: its drinker kept it in his liver for more than a week, well curled up and tranquil, as a reserve aliment for a sudden effort; an effort that he was forced to make the following Sunday, pursuing…
There are something like ten million million million million million million million million million million million million million million (1 with eighty zeroes after it) particles in the region of the universe that we can observe. Where did they all come from? The answer is that, in quantum theory, particles can be…
In general I would be cautious against … plays of fancy and would not make way for their reception into scientific astronomy, which must have quite a different character. Laplace's cosmogenic hypotheses belong in that class. Indeed, I do not deny that I sometimes amuse myself in a similar manner, only I would never…