N. 3 - 21 aprile 2001 - Giano Bifronte

greatest scientist of all times - or at least many people think so! - and
the elusive ether.
Let us see the question with the author's own words (Introduction):
"In the eyes of most physicists and philosophers, Albert Einstein has
acquired a reputation for abolishing the concept of the ether as a
medium filling space (or identified with it), which was responsible for
carrying electromagnetic, gravitational and other interactions. Today,
this notion is echoed in textbooks, encyclopaedias, and scientific
reviews. However, it does not fully reflect the historical truth, and in a
sense even represents a distortion [...] Einstein denied the existence of
the ether for only 11 years - from 1905 to 1916. Thereafter, he
recognized that his attitude was too radical and even regretted that his
works published before 1916 had so definitely and absolutely rejected
the existence of the ether."
The author proves this assertion directly referring to the opinions
which Einstein himself expressed during his life, in a book which is
therefore full of quotations and precise bibliographical references (up to
the point of quoting even the original Deutsch passages in a special
appendix). Here they are some examples of Einstein's thoughts:
"It would have been more correct if I had limited myself, in my earlier
publications, to emphasizing only the nonexistence of an ether velocity,
instead of arguing the total nonexistence of the ether, for I can see that
with the word ether we say nothing else than that space has to be
viewed as a carrier of physical qualities."
Moreover:
" [...] in 1905 I was of the opinion that it was no longer allowed to
speak about the ether in physics. This opinion, however, was too
radical, as we will see later when we discuss the general theory of
relativity. It does remain allowed, as always, to introduce a medium
filling all space and to assume that the electromagnetic fields (and
matter as well) are its states. [...] once again 'empty' space appears as
endowed with physical properties, i.e., no longer as physically empty, as
seemed to be the case according to special relativity [...] ".
And again:
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