Documentos

Sidelights on Relativity / Albert Einstein

ETHER AND THE THEORY OF RELATIVITY
An Address delivered on May 5th, 1920, in the University of Leyden
How does it come about that alongside of the idea of ponderable
matter, which is derived by abstraction from everyday life, the
physicists set the idea of the existence of another kind of matter,
the ether? The explanation is probably to be sought in those phenomena
which have given rise to the theory of action at a distance, and
in the properties of light which have led to the undulatory theory.
Let us devote a little while to the consideration of these two
subjects.

Estudo da propagação de rádio e das descargas atmosféricas na região da anomalia magnética do atlântico sul / Ângelo Antônio Leithold

O presente trabalho tem dois objetivos específicos: o primeiro é o monitoramento da variação
de propagação de radiofrequência na faixa de 7,00 MHz, influenciada pelas condições
iônicas da alta atmosfera, que por sua vez são determinadas pela atividade solar. O segundo,
estuda a relação entre a quantidade de descargas atmosféricas na região em que
a AMAS está mais próxima da superfície, comparada a outras regiões fora do “mergulho”
do cinturão interno de Van Allen.

A Verdade Sufocada / Carlos Alberto Brilhante Ustra

Pede-me o meu am1go Carlos Alberto Bri lhante Us.tra que escreva uma
apresentação – um prefácio – para seu novo l ivro. Costuma-se dizer que se um
hvro é bom não precisa de prefácio c se não presta não há prefácio que o salve.
O novo livro do Ustra não precisa de prefácio, como dele não precisou o seu
coraJOSO Rompendo o Silêncio.
Pelos frutos se conhece a árvore, pois árvore má não dá bons frutos. Prefiro,
ass1m, falar do autor antes que do seu livro. Pelo autor os leitores poderão
avaliar a importância do l ivro.
Conheci o autor quando me mandaram comandar a Arti I haria Di visionária
em Porto Alegre, que tinha como uma das unidades subordinadas o Grupo de
Arti I h a ria de São Leopoldo comandado pelo então tenente-coronel Carlos
Al berto Bri lhante Ustra.

Democracy and Education / John Dewey

Chapter One: Education as a Necessity of Life
1. Renewal of Life by Transmission. The most notable
distinction between living and inanimate things is that the
former maintain themselves by renewal. A stone when struck
resists. If its resistance is greater than the force of the blow
struck, it remains outwardly unchanged. Otherwise, it is
shattered into smaller bits. Never does the stone attempt to
react in such a way that it may maintain itself against the blow,
much less so as to render the blow a contributing factor to its
own continued action. While the living thing may easily be
crushed by superior force, it none the less tries to turn the
energies which act upon it into means of its own further
existence. If it cannot do so, it does not just split into
smaller pieces (at least in the higher forms of life), but loses
its identity as a living thing.

20,000 Leagues Under the Seas – An Underwater Tour of the World / Julio Verne

Introduction
“The deepest parts of the ocean are totally unknown to us,”
admits Professor Aronnax early in this novel. “What goes on in
those distant depths? What creatures inhabit, or could inhabit,
those regions twelve or fifteen miles beneath the surface of the water?
It’s almost beyond conjecture.”
Jules Verne (1828-1905) published the French equivalents of these words
in 1869, and little has changed since. 126 years later, a Time
cover story on deep-sea exploration made much the same admission:
“We know more about Mars than we know about the oceans.”
This reality begins to explain the dark power and otherworldly
fascination of Twenty Thousand Leagues Under the Seas.

Aesop’s Fables / Esopo

The Cock and the Pearl
A cock was once strutting up and down the farmyard
among the hens when suddenly he espied something
shinning amid the straw. ‘Ho! ho!’ quoth he, ‘that’s for
me,’ and soon rooted it out from beneath the straw. What
did it turn out to be but a Pearl that by some chance had
been lost in the yard? ‘You may be a treasure,’ quoth
Master Cock, ‘to men that prize you, but for me I would
rather have a single barley-corn than a peck of pearls.’
Precious things are for those that can prize them.