Enrique Loedel Palumbo
Encyclopedia
Enrique Loedel Palumbo was a Latin American physicist
.
Loedel Palumbo was born in Montevideo, Uruguay and studied at the University of La Plata in Argentina
. He wrote his Ph.D. thesis on optical and electrical constants of sugar cane. He then began his career as professor in La Plata.
During Einstein's
visit to Argentina in 1925 they had a conversation which resulted in a paper published by Loedel in Physikalische Zeitschrift
. It is claimed that this is the first research paper on relativity ever published by a Latin American scientist.
Loedel Palumbo then spent some time in Germany
working with Erwin Schroedinger and Max Planck
. He returned to Argentina in 1930 and from there on concentrated on teaching. He published several scientific papers during his career in international journals and wrote several books (in Spanish). A lasting contribution to the teaching of special relativity
is the "Loedel space-time diagrams", a symmetrical representation of Minkowski diagram
s still used in some texts today.
Loedel Palumbo's view of spacetime was also described in 1955 by Henri Amar of the Franklin Institute
. On the basis of work in 1948 by Loedel Palumbo, Amar wrote in 1957 "I regret my unfamiliarity with South American literature and wish to acknowledge the priority of Professor Loedel's work". The American Journal of Physics
printed this concession as well as a note by Loedel Palumbo citing his publications on the geometrical representation of Lorentz transformations.
. Loedel Palumbo hypothesized two collinear velocities v and w. Does there exist a frame of reference in which the velocities transform to equal speeds in opposite directions? The affirmative answer was communicated by Loedel Palumbo in Physikalische Zeitschrift.
A quick demonstration uses modern algebra to make the resolution:
Suppose
and 
, so that a and b are rapidities
corresponding to velocities v and w. Let m = (a + b)/2, the midpoint rapidity. The transformation
of the split-complex number
plane represents the required transformation since
and 
As the exponents are additive inverse
s of each other, the images represent equal speeds in opposite directions.
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
.
Loedel Palumbo was born in Montevideo, Uruguay and studied at the University of La Plata in Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
. He wrote his Ph.D. thesis on optical and electrical constants of sugar cane. He then began his career as professor in La Plata.
During Einstein's
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...
visit to Argentina in 1925 they had a conversation which resulted in a paper published by Loedel in Physikalische Zeitschrift
Physikalische Zeitschrift
Physikalische Zeitschrift was a German scientific journal of physics published from 1899 to 1945 by S. Hirzel Verlag...
. It is claimed that this is the first research paper on relativity ever published by a Latin American scientist.
Loedel Palumbo then spent some time in Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
working with Erwin Schroedinger and Max Planck
Max Planck
Max Karl Ernst Ludwig Planck, ForMemRS, was a German physicist who actualized the quantum physics, initiating a revolution in natural science and philosophy. He is regarded as the founder of the quantum theory, for which he received the Nobel Prize in Physics in 1918.-Life and career:Planck came...
. He returned to Argentina in 1930 and from there on concentrated on teaching. He published several scientific papers during his career in international journals and wrote several books (in Spanish). A lasting contribution to the teaching of special relativity
Special relativity
Special relativity is the physical theory of measurement in an inertial frame of reference proposed in 1905 by Albert Einstein in the paper "On the Electrodynamics of Moving Bodies".It generalizes Galileo's...
is the "Loedel space-time diagrams", a symmetrical representation of Minkowski diagram
Minkowski diagram
The Minkowski diagram was developed in 1908 by Hermann Minkowski and provides an illustration of the properties of space and time in the special theory of relativity. It allows a quantitative understanding of the corresponding phenomena like time dilation and length contraction without mathematical...
s still used in some texts today.
Loedel Palumbo's view of spacetime was also described in 1955 by Henri Amar of the Franklin Institute
Franklin Institute
The Franklin Institute is a museum in Philadelphia, Pennsylvania, and one of the oldest centers of science education and development in the United States, dating to 1824. The Institute also houses the Benjamin Franklin National Memorial.-History:On February 5, 1824, Samuel Vaughn Merrick and...
. On the basis of work in 1948 by Loedel Palumbo, Amar wrote in 1957 "I regret my unfamiliarity with South American literature and wish to acknowledge the priority of Professor Loedel's work". The American Journal of Physics
American Journal of Physics
The American Journal of Physics is a monthly, peer-reviewed scientific journal published by the American Association of Physics Teachers and the American Institute of Physics. The editor is Jan Tobochnik of Kalamazoo College.-Aims and scope:...
printed this concession as well as a note by Loedel Palumbo citing his publications on the geometrical representation of Lorentz transformations.
Loedel frame
When Albert Einstein was in La Plata, Loedel Palumbo asked him about the existence of a particular type of frame of referenceFrame of reference
A frame of reference in physics, may refer to a coordinate system or set of axes within which to measure the position, orientation, and other properties of objects in it, or it may refer to an observational reference frame tied to the state of motion of an observer.It may also refer to both an...
. Loedel Palumbo hypothesized two collinear velocities v and w. Does there exist a frame of reference in which the velocities transform to equal speeds in opposite directions? The affirmative answer was communicated by Loedel Palumbo in Physikalische Zeitschrift.
A quick demonstration uses modern algebra to make the resolution:
Suppose
and , so that a and b are rapiditiesRapidity
In relativity, rapidity is an alternative to speed as a framework for measuring motion. On parallel velocities rapidities are simply additive, unlike speeds at relativistic velocities. For low speeds, rapidity and speed are proportional, but for high speeds, rapidity takes a larger value. The...
corresponding to velocities v and w. Let m = (a + b)/2, the midpoint rapidity. The transformation
of the split-complex numberSplit-complex number
In abstract algebra, the split-complex numbers are a two-dimensional commutative algebra over the real numbers different from the complex numbers. Every split-complex number has the formwhere x and y are real numbers...
plane represents the required transformation since
and As the exponents are additive inverse
Additive inverse
In mathematics, the additive inverse, or opposite, of a number a is the number that, when added to a, yields zero.The additive inverse of a is denoted −a....
s of each other, the images represent equal speeds in opposite directions.
Key publications
- Fisica relativista, Kapelusz Editorial, Buenos Aires, Argentina (1955).
- "Die Form der Raum--Zeit-Oberfläche eines Gravitationsfeldes, das von einer punkt-förmigen Masse herrürt", Physikalische ZeitschriftPhysikalische ZeitschriftPhysikalische Zeitschrift was a German scientific journal of physics published from 1899 to 1945 by S. Hirzel Verlag...
XXVII: 645-648 (1926). - "Ueber die Quantifizierte Rotation der Atome", Physikalische Zeitschrift 31: 926-929 (1930)