Olinto De Pretto

Olinto De Pretto (born April 26, 1857 in Schio , Vicenza province , † March 16, 1921 ) was an Italian engineer and agronomist who also dealt with questions of geology and physics and in discussions about the prehistory of the formula for the equivalence of mass and energy was mentioned.

Olinto de Pretto 1898

De Pretto was one of seven children of the architect Pietro De Pretto (1810-1891), who also dealt with astronomy and geology. De Pretto attended the Higher Agricultural School in Milan, where he studied geology as well as agriculture. After graduation in 1879 he was assistant to Gaetano Cantoni. After his death in 1887 he ran the foundry of his older brother Silvio.

With his brothers Silvio and Augusto he founded an Alpine Club and with his brother Augusto he published a first geological treatise on the interrelationship between mountain formation and glaciers in 1888, which was also published again in the Bulletin of the Italian Geological Society in 1892. This was followed by further work on geology.

From 1899 he also dealt with speculations about the connection between the newly discovered phenomenon of radioactivity and the ether theory . He was also particularly interested in astronomical applications (the energy source of the stars, a great unsolved problem at the time).

In 1906 De Pretto was accepted into the Accademia dei Lincei .

Equivalence of mass and energy

In 1903 he published his essay Ipotesi dell'Etere nella Vita dell'Universo "(Hypotheses about the ether in the life of the universe ) in the treatises of the Venetian Society of Sciences , where he assumed that matter corresponds to an enormous reservoir of energy from the notion of matter as ether particles, which travel at the speed of light. Similar ideas were common at the time, and were, for example, previously also in 1875 by the British engineer Samuel Tolver Preston published ( Physics of the ether ) carried by Le Sage's theory of gravitation influences De Pretto also brought these ideas into connection with the great energies of unknown origin in radioactivity and in astronomy and geology (source of geothermal heat) and postulated the transformation of a kind of rest energy of the ether stored in the matter Astronomer Giovanni Schiaparelli from Milan praised, found but otherwise little attention.

De Pretto used the expression for the "living force" contained in matter, identifying with the speed of light . This formula is true apparently with the formula of Albert Einstein agreed that this was derived in 1905 as a consequence of his special theory of relativity. ${\ displaystyle mv ^ {2}}$ ${\ displaystyle v}$ ${\ displaystyle c}$ ${\ displaystyle E = mc ^ {2}}$

As Ignazio Marchioro showed, De Pretto's formula was by no means identical to Einstein's equivalence formula, because at that time "living force" was just another expression for the kinetic energy , which is only half the relativistic value. Now De Pretto calculated the energy of a body (in kcal ) - according to Bartocci, 8338 actually represents twice the value of the heat equivalent (the correct value is 4186.05, where De Pretto used the outdated value 4169). This results in: ${\ displaystyle {\ tfrac {1} {2}} mv ^ {2}}$ ${\ displaystyle {\ tfrac {mv ^ {2}} {8338}}}$

{\ displaystyle {\ frac {1} {2}} {\ frac {mv ^ {2}} {4169}} = {\ frac {mv ^ {2}} {8338}}}

,

consequently De Pretto actually only used the classical formula for the kinetic energy for the energy reservoir in matter, and not . ${\ displaystyle E = mc ^ {2}}$

Mathematics professor (and critic of the theory of relativity ) Umberto Bartocci speculated that De Pretto Einstein's essay was known and inspired. After Bartocci, Augusto De Pretto gave the essay to his friend Beniamino Besso in Rome, who in turn was the uncle of Michele Besso , Einstein's close friend in Bern. Ignazio Marchioro objected that there was no connection between De Pretto's formula and the theory of relativity, since he based his considerations on the ether, which no longer exists in the theory of relativity, and (as shown above) De Pretto only the formula for the kinetic energy used. Bartocci admits the latter, but he sticks to his opinion that Einstein was at least inspired by De Pretto's idea of an enormous energy reservoir in matter.

Individual evidence

↑ Atti del Reale Istituto Veneto di Scienze, Lettere ed Arti , Volume 63, dated November 29, 1903 Reproduction of his article with a letter of praise from Schiaparelli from 1903

↑ ^a ^b Archived copy ( Memento of the original from April 14, 2012 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2
↑ ^a ^b http://www.cartesio-episteme.net/st/DEPR-003.htm
↑ Bartocci Albert Einstein e Olinto De Pretto. La vera storia della formula più famosa del mondo , Bologna, Andromeda, 1999. See also the biography of De Pretto, speculation by Bartocci

personal data
SURNAME	De Pretto, Olinto
BRIEF DESCRIPTION	Italian engineer and agronomist
DATE OF BIRTH	April 26, 1857
PLACE OF BIRTH	Schio
DATE OF DEATH	March 16, 1921

[1] Atti del Reale Istituto Veneto di Scienze, Lettere ed Arti , Volume 63, dated November 29, 1903 Reproduction of his article with a letter of praise from Schiaparelli from 1903