Famous Physicists

Scientists in physics

Physics is one of the main branches of STEM (science, technology, engineering and mathematics). It contains many fields of study within it, like nuclear physics, mechanics, electronics, etc. and it is closely linked with mathematics.

Even though we consider physics a separate branch nowadays, the separation between the sciences is not as clear as it may seem. For centuries, scientists who contributed to physics also contributed to mathematics, chemistry and even biology. Thus, some names might be renowned in several fields. In fact, in this article, you might find names that you have heard of in other sciences before.

Galileo Galilei

One of the most famous polymaths (a person who is interested and knows in topics that cover a broad range of knowledge) is Galileo Galilei (1564 - 1642). Born in Italy in the 16th century, he was an astronomer, physicist and engineer. Galileo is famous for his numerous contributions to the fields of astronomy and physics, including:

• the discovery of the four largest moons of Jupiter,
• the observation of sunspots,
• his work on the laws of motion and the principle of inertia, and
• the invention of the telescope.

Fig. 1. Galileo Galilei portrait.

Galileo's support for the heliocentric model of the solar system, proposed by Copernicus in 1543, brought him into conflict with the Catholic Church. Copernicus' book on the subject had been banned, as the heliocentric model was considered heresy by the Church. Galileo was judged for initially supporting this model, and sentenced to house arrest for the rest of his life. If he had not renounced the heliocentric model during the trial, he could have been sentenced to death.

Famous nuclear physicists

The study of atomic nuclei and their properties and behaviour constitutes the field of nuclear physics. This area of physics encompasses an investigation into the composition and structure of atomic nuclei, as well as the interactions that occur between atomic nuclei and subatomic particles. Nuclear physics also encompasses the applications of nuclear energy in diverse fields, including energy production, medicine, and materials science.

The applications of nuclear physics range from life-saving uses such as tests and treatments for cancer to mass-destruction weapons like the atomic bomb. All of these applications are owed in part to the famous nuclear physicists that paved the way to where we are now:

• Lise Meitner (1878 - 1968): Meitner was an Austrian physicist who is best known for her contributions to the discovery of nuclear fission. She was one of the few women in her field during her time and faced discrimination due to her sex and Jewish heritage.

• Enrico Fermi (1901-1954): Fermi was an Italian physicist who was instrumental in the development of the first nuclear reactor. He won the Nobel Prize in Physics for his work on nuclear reactions.

• Marie Curie (1867 - 1934): Curie was a Polish-born physicist and chemist who is best known for her pioneering work in the field of radioactivity. She was the first woman to win a Nobel Prize, the first person to win two Nobel Prizes in different fields, and the first female professor at the University of Paris.

• Robert Oppenheimer (1904 - 1967): Oppenheimer was the director of the Manhattan Project, which developed the first atomic bomb. He is often referred to as the "father of the atomic bomb." However, he opposed the creation of the hydrogen bomb, and following the war, Oppenheimer became an outspoken opponent of nuclear weapons and a leading advocate for arms control and disarmament.

• Niels Bohr (1885 - 1962): Bohr made important contributions to the development of quantum mechanics and the understanding of atomic structure. He proposed the Bohr model of the atom, which describes electrons as orbiting the nucleus in discrete energy levels.

Table 1. Famous nuclear physicists - name, birth and death dates, significant contributions and photo
Name	Born	Died	Contributions	Photo
Lise Meitner	7 November 1878, Austria-Hungary	27 October 1968, England	Discovery of nuclear fission Protactinium Auger–Meitner effect Meitner–Hupfeld effect	Fig. 2. Lise Meitner receiving the Fermi award. Wikimedia Commons
Enrico Fermi	29 September 1901, Italy	28 November 1954, USA	First self-sustaining nuclear chain Fermion Fermi gas Fermi-Dirac statistics Fermi's golden rule Fermi method Fermi paradox Fermi theory of beta decay Thomas-Fermi model and screening Chandrasekhar-Fermi method	Fig.3 Enrico Fermi portrait.
Marie Curie	7 November 1867, Poland	4 July 1934, France	Nuclear research pioneer Discovery of polonium and radium	Fig. 6. Marie Curie portrait. Wikimedia Commons
Robert Oppenheimer	22 April 1904, USA	18 February 1967, USA	Nuclear weapons development Tolman–Oppenheimer–Volkoff equation Tolman–Oppenheimer–Volkoff limit Oppenheimer–Phillips process Born–Oppenheimer approximation	Fig. 4. Oppenheimer at ground zero of the atomic bomb trials
Niels Bohr	7 October 1885, Denmark	18 November 1962, Denmark	Bohr magneton Bohr atomic model Bohr radius Bohr–Kramers–Slater theory Bohr–Van Leeuwen theorem Bohr–Sommerfeld theory Complementarity	Fig. 5. Niels Bohr portrait. Wikimedia Commons

Famous theoretical physicists

Theoretical physics is a branch of physics that employs mathematical models and abstractions to help comprehend and elucidate natural phenomena. This field is particularly useful in areas where experimental data is limited or absent and paves the way for future demonstrations. Theoretical physicists devise theories and hypotheses using advanced mathematical concepts, to describe the behaviour of the universe on both a microscopic and macroscopic level.

The work of theoretical physicists is centred on developing new models and theories that can explain existing observations and make predictions regarding the behaviour of the universe. The scope of their research encompasses a vast array of topics, including quantum mechanics, general relativity, and particle physics. Some of the most renowned theoretical physicists are:

• Albert Einstein (1879 - 1955): Einstein is known for his theories of relativity, which transformed our understanding of space and time. He also made significant contributions to quantum mechanics and the development of the atomic bomb, which he later opposed for ethical reasons.

• Stephen Hawking (1942 - 2018): Hawking was an English physicist currently known for his work on black holes and the origins of the universe. You might know him from his multiple popular science books like "A Brief History of Time", or the movie based on his life, "The History of Everything".

• Richard Feynman (1918 - 1988): Feynman specialised in quantum mechanics. He proposed the concept of quantum electrodynamics, which describes the interactions between particles and electromagnetic fields. Feynman also made contributions to the development of the atomic bomb.

• Max Planck: Max Planck was a German theoretical physicist who is considered one of the founders of quantum mechanics. He is known for his work on the relationship between energy and frequency, which led to the development of the concept of the photon. In Germany, the Max Planck Society is a prestigious university-independent research compendium of 86 research institutes spanning from physics to law.

• Erwin Schrödinger: Erwin Schrödinger was an Austrian theoretical physicist whose research focused on quantum mechanics. He is best known for his thought experiment involving a cat, known as "Schrödinger's cat". The experiment is designed to demonstrate the paradoxical nature of quantum superposition, which is the idea that subatomic particles can exist in multiple states at the same time.

Table 2. Famous theoretical scientists - names, birth and death dates, significant contributions and photos.
Name	Birth	Death	Contributions	Photo
Albert Einstein	14 March 1879, German Empire	18 April 1955, USA	General and special relativity Photoelectric effect Mass-energy equivalence (\(E = mc^2\)) Planck-Einstein relation (\(E = hf\))	Fig. 7. Albert Einstein portrait. Wikimedia Commons
Stephen Hawking	8 January 1942	14 March 2018	Singularity theorem Second law of black hole dynamics Hawking radiation	Fig. 8. Stephen Hawking portrait. Wikimedia Commons
Richard Feynman	11 May 1918, USA	15 February, 1988	Manhattan Project Acoustic wave equation Bethe–Feynman formula Feynman diagrams, gauge, point, propagator, parametrization Feynman–Kac formula Hellmann–Feynman theorem Heaviside-Feynman formula V−A theory Brownian ratchet Feynman–Stueckelberg interpretation One-electron universe Path integral formulation Quantum cellular automata, computing, dissipation, electrodynamics, hydrodynamics, logic gates, turbulence Resummation Shaft passer Sticky bead argument Synthetic molecular motor Universal quantum simulator Vortex ring model Wheeler–Feynman absorber theory Variational perturbation theory	Fig. 9. Richard Feynman portrait in class. Wikimedia Commons
Max Planck	23 April 1858, German Confederation	4 October 1947, Allied-occupied Germany	Planck constant Planck postulate Planck's law of black body radiation Planck–Einstein relation Planck units Planckian locus Boltzmann–Planck equation Fokker–Planck equation Nernst–Planck equation	Fig. 10. Max Planck portrait. Wikimedia Commons
Erwin Schrödinger	12 August 1887, Austria-Hungary	4 January 1961, Austria	Schrödinger equation Schrödinger's cat Schrödinger method Schrödinger functional Schrödinger group Schrödinger field Rayleigh-Schrödinger perturbation Robertson–Schrödinger uncertainty relations Schrödinger–HJW theorem Schrödinger's pure-affine theory Qualia Quantum entanglement Quantum superposition Quantum steering	Fig. 11. Erwin Schrödinger portrait. Wikimedia Commons.

Famous female physicists

• Chien-Shiung Wu (1912 - 1997): Chien-Shiung Wu was a Chinese-American physicist who is especially known for the discovery of parity violation in nuclear physics. Parity is a fundamental symmetry in physics that relates to the behaviour of a physical system under mirror reflection. In certain types of nuclear decay, such as beta decay, the parity of the resulting particles is not conserved. This means that the resulting particles are not mirror images of their initial state, and the process violates parity symmetry. The discovery of parity violation in nuclear decay was a significant milestone in the study of fundamental symmetries in physics.

• Vera Rubin (1928 - 2016): Rubin was an American astronomer who focused on explaining dark matter. She was the first woman to be allowed to observe at the Palomar Observatory, and she was awarded the National Medal of Science in 1993.

• Emmy Noether (1882 - 1935): Noether was a German mathematician and physicist who made significant contributions to the development of abstract algebra and theoretical physics. She is known for her theorem, which relates symmetries in physics to conservation laws, and she was the first woman to obtain a doctorate in mathematics from the University of Erlangen.

American Physicists

There are important physicists of diverse nationalities. However, in this article, we will focus on scientists from the United States and Britain.

• Steven Weinberg (1933 - 2021): Weinberg won the Nobel Prize in Physics in 1979 for his work on the unification of two of the fundamental forces of nature - the electromagnetic and weak nuclear forces. He has also made significant contributions to the theory of cosmology and the study of particle physics.

• Murray Gell-Mann (1929 - 2019): Gell-Mann won the Nobel Prize in Physics in 1969 for his work on the classification of subatomic particles known as hadrons. He also proposed the concept of quarks, which are now considered to be the building blocks of protons and neutrons.

• Lisa Randall (1962 - ): Randall is a theoretical physicist who has significantly contributed to the field of particle physics and the study of extra dimensions. She is known for her work on the Randall-Sundrum model, which proposes the existence of a hidden extra dimension of space.

Table 4. Famous American Physicists: names, birth and death dates, contributions and photo
Name	Birth	Death	Contributions	Photo
Steven Weinberg	3 May 1933, USA	23 July 2021, USA	Electroweak interaction Weinberg angle Weinberg–Witten theorem Joos–Weinberg equation Asymptotic safety Minimal subtraction scheme Unitarity gauge	Fig. 15. Steven Weinberg portrait. Wikimedia Commons.
Murray Gell-Mann	15 September 1929, USA	24 May 2019, USA	Coining the term "quark" Quark model Quantum chromodynamics Neutral particle oscillation Gell-Mann and Low theorem Gell-Mann matrices Gell-Mann−Low renormalization group equation Gell-Mann–Nishijima formula Gell-Mann–Okubo mass formula Sigma model of pions Seesaw theory of neutrino masses Plectics	Fig. 16. Murray Gell-Mann. Wikimedia Commons.
Lisa Randall	18 June 1962, USA	---	Randall–Sundrum model Warped Passages (2005)	Fig. 17. Lisa Randall portrait. Wikimedia Commons

British Physicists

As with many other countries, Britain has fostered great physicists, historical and contemporary.

• Isaac Newton (1642 - 1726): who doesn't know Newton? He has to be one of the most famous physicists in history. He is known for his laws of motion and his theory of gravitation, which revolutionized our understanding of the universe. Newton also made important contributions to the development of calculus.

• James Clerk Maxwell (1831 - 1879): Maxwell was a Scottish physicist who is known for his work on electromagnetic theory. He proposed a set of equations that describe the behaviour of electric and magnetic fields, which helped pave the way for the development of modern electronics.

• Paul Dirac (1902 - 1984): Dirac was an English physicist who worked in the field of quantum mechanics. He proposed the existence of antimatter and formulated the famous Dirac equation, which describes the behaviour of electrons in a relativistic quantum field.

• Michael Faraday (1791 - 1867): Faraday was an English physicist and chemist who made important contributions to the study of electromagnetism. He discovered electromagnetic induction and formulated Faraday's laws of electrolysis, which describe the relationship between electric current and chemical reactions.

Table 5. Famous British physicists: names, birth and death dates, contributions, photo.
Name	Birth	Deat	Contributions	Photo
Isaac Newton	4 January 1643, England	31 March 1727, Great Britain	Newtonian mechanics Universal gravitation Newton's laws of motion Newton's law of cooling Newton's identities Newton–Gauss line Newtonian fluid Newton's rings	Fig. 18. Isaac Newton painted portrait. Wikimedia Commons
James Clerk Maxwell	13 June 1831, Scotland	5 November 1879, England	Maxwell relations Maxwell–Betti theorem Maxwell–Boltzmann distribution Maxwell–Boltzmann statistics Maxwell–Stefan diffusion	Fig. 19. James Clerk Maxwell painted portrait. Wikimedia Commons
Paul Dirac	8 August 1902, England	20 October 1984, USA	Dirac–Coulomb–Breit Equation Dirac constant Dirac delta function Dirac equation Dirac fermion	Fig. 20. Paul Dirac portrait. Wikimedia Commons
Michael Faraday	22 September 1791, England	25 August 1867, England	Faraday's law of induction Faraday constant Faraday's laws of electrolysis	Fig. 21. Michael Faraday portrait. Wikimedia Commons

Famous physicists today

Physics is not dead! Although the research in physics (and other STEM branches) has been radically transformed over the last centuries, and many extremely important discoveries have been made, there is still a lot to unravel within this scientific discipline. Thus, the contribution of current physicists to the field is extremely important and deserves recognition.

• Lisa Randall (1962 - ), already mentioned in this article, is a theoretical physicist and professor at Harvard University. Her work focuses on particle physics and cosmology, with a particular emphasis on the relationship between gravity and the structure of the universe. Randall is best known for her work on the theory of extra dimensions,which proposes that our universe may be embedded within a larger, higher-dimensional space. Her work has helped to explain why gravity is so much weaker than other fundamental forces and has provided a framework for understanding the behaviour of particles at high energies.

• Brian Greene (1963 - ) is a theoretical physicist and string theorist whose work focuses on the mathematical underpinnings of the universe and the nature of space and time. Greene is best known for his work on string theory, which proposes that the fundamental building blocks of the universe are not particles but rather tiny, one-dimensional objects called strings. His research has helped to explain the nature of gravity and has provided a framework for understanding the behaviour of particles at high energies.

• Michio Kaku (1947 - ) whose work focuses on the unification of the fundamental forces of nature and the nature of time. Kaku is best known for his work on string theory, which proposes that the fundamental building blocks of the universe are not particles but rather tiny, one-dimensional objects called strings. He has also worked on the theory of everything, which seeks to unify all of the fundamental forces of nature into a single, cohesive framework.

• Kip Thorne (1940 - )is a theoretical physicist and Nobel laureate who works on the properties of space and time, as well as the behaviour of matter and energy in extreme environments. Thorne is best known for his work on the theory of relativity, particularly the study of gravitational waves. He was one of the founders of the Laser Interferometer Gravitational-Wave Observatory (LIGO), which successfully detected gravitational waves for the first time in 2015. This groundbreaking discovery opened up a new window into the universe, allowing scientists to observe and study objects and phenomena that were previously hidden from view.

• Ed Witten (1951 - ) is a theoretical physicist and mathematician who focuses on the unification of the fundamental forces of nature and the nature of space and time. Witten is best known for his work on string theory. He also developed M-theory, a more encompassing theory that includes multiple dimensions and branes.

Table 6. Famous scientists of today: names, date of birth, contributions and photo
Name	Birth	Contributions	Photo
Brian Greene	9 February 1963, USA	Contributions to string theory The Elegant Universe The Fabric of the Cosmos The Hidden Reality	Fig. 22. Brian Greene portrait. Wikimedia Commons
Michio Kaku	24 January 1947, USA	Contributions to string field theory Physics of the Impossible Physics of the Future The Future of the Mind The God Equation	Fig. 23. Michio Kaku portrait. Wikimedia Commons
Kip Thorne	1 June 1940, USA	Thorne-Żytkow object Thorne-Hawking-Preskill bet Laser Interferometer Gravitational Wave Observatory (LIGO) Gravitational waves Gravitation	Fig. 24. Kip Thorne portrait. Wikimedia Commons
Ed Witten	26 August 1951, USA	M-theory Seiberg–Witten theory Seiberg–Witten map Seiberg–Witten invariants	Fig. 25. Ed Witten portrait. Wikimedia Commons

Current famous physicists are normally not only physicists, but they also dedicate their time to spreading their love and understanding of physics to the rest of the world. In other words, they are science communicators and authors of scientific non-fiction books as well as researchers. Their contribution in that respect is harder to quantify, but extremely important too, to help dispel myths surrounding science and motivate future generations to participate in science or become scientifically literate. As the world becomes more technological, it is important that we understand the basics of science and technology to keep up.