César Lattes is not one of the most famous physicists in the world, but Google wants to change that. Today, Google has paid homage to Lattes with the “Doodle treatment”.

Cesar Lattes was a pioneering Brazilian physicist renowned for his crucial role in the discovery of the pion, a subatomic particle that confirmed the theory of nuclear forces. A pion is composed of a quark and an antiquark. Lattes’ innovative experimental techniques in cosmic ray research and his commitment to international scientific collaboration left a lasting legacy, influencing modern physics and inspiring future generations of physicists.

“Happy birthday César Lattes,” Google wrote of the Doodle. “Thank you for paving the way for experimental physics in Latin America and around the world.”

International physics

Cesar Lattes was born on July 11, 1924, in Curitiba, Brazil, the capital and largest city in the state of Paraná in Southern Brazil. From a young age, Lattes exhibited a profound curiosity about the natural world. This curiosity, coupled with a supportive family environment, set him on the path to scientific inquiry.

Lattes pursued his higher education at the University of São Paulo, where he studied under the guidance of Gleb Wataghin, a Russian-born physicist who played a crucial role in the development of physics research in Brazil. Wataghin’s mentorship was instrumental in shaping Lattes’ scientific perspective and his approach to research. It was also there that Lattes first made a name for himself as a bold and inquisitive researcher with a sharp mind.

From 1946 to 1948, Lattes launched on his main research line by studying cosmic rays. In the mid-20th century, the study of cosmic rays was a burgeoning field, holding the promise of unlocking the secrets of the universe’s most energetic particles. Cosmic rays are high-energy particles originating from outer space, and their interactions with Earth’s atmosphere produce a shower of secondary particles.

However, Lattes was searching for connections with other researchers as well.

He travelled to England arriving in February 1946, joining another one of his mentors, Giuseppe Occhialini. Together, they started work at the University of Bristol,

In 1947, Lattes, along with Giuseppe Occhialini and Cecil Powell at the University of Bristol in England, made a monumental discovery. They identified the pion (or pi-meson), a subatomic particle predicted by Japanese physicist Hideki Yukawa in 1935. The discovery of the pion was crucial because it confirmed Yukawa’s theory of nuclear forces, which described how protons and neutrons are held together in the atomic nucleus.

The pion and the physicist

Pions are composed of a quark and an antiquark and come in three charge states: positively charged, negatively charged, and neutral. These particles were first predicted by Yukawa in 1935 as part of his theory explaining the interaction between protons and neutrons in the nucleus.

Quarks are fundamental particles that form the building blocks of hadrons, such as protons and neutrons. An antiquark is the antimatter counterpart of a quark, having the same mass but opposite electric charge and other quantum properties.

The discovery of pions provided significant insights into the nature of the strong nuclear force, one of the four fundamental forces in the universe. Pions mediate the strong force by being exchanged between nucleons (protons and neutrons) within an atomic nucleus, effectively holding the nucleus together despite the repulsive electromagnetic force between positively charged protons.

All these particles are described in the Standard Model, which describes all the known particles and their interactions. Lattes’ work helped cement an important part of this theory.

Returning to Brazil, Lattes was determined to establish a strong foundation for scientific research in his home country. In 1949, he played a pivotal role in founding the Brazilian Center for Research in Physics (Centro Brasileiro de Pesquisas Físicas, or CBPF) in Rio de Janeiro. The CBPF became a cornerstone of scientific research in Brazil, fostering a new generation of physicists and promoting international collaboration.

Under Lattes’ leadership, the CBPF attracted prominent scientists from around the world and conducted cutting-edge research in various areas of physics. His vision and dedication were instrumental in elevating Brazil’s status in the global scientific community.

By today’s standards, the Brazilian physicist might have been awarded a Nobel Prize. This is obviously still speculation, but the discovery was awarded a Nobel Prize. However, it was awarded only to Cecil Powell, as the Nobel Committee policy at the time was to only award the prize to the research group head, and not to other researchers who worked at the problem.

Nevertheless, Lattes was a globally celebrated physicist. His contribution improved our understanding of the world and helped grow the physics community in Brazil and South America.

Lattes’ legacy is a testament to the enduring impact of curiosity, creativity, and cooperation in the quest for knowledge. We’re happy to see Google celebrate him.