Gary Felder

Gary Felder
Residence	Northampton, MA, United States
Alma mater	Oberlin College, Stanford University
Known for	IAAD, Bell's Theorem, EPR, LATTICEEASY
Scientific career
Fields	Physics, cosmology
Institutions	Smith College
Doctoral advisor	Andrei Linde

Gary N. Felder is an American physicist and a Professor of Physics at Smith College in Northampton, Massachusetts. His research centers on inflationary cosmology, numerical simulations of the early universe, and computational and written tools for teaching physics. He is the co-author, with his brother Kenny Felder, of the textbooks Mathematical Methods in Engineering and Physics and Modern Physics.

Biography

Felder grew up in North Carolina and earned a B.A. from Oberlin College. After taking a break of several years between undergraduate and graduate study, during which he traveled through Europe, Israel, and Central America, he completed a Ph.D. in physics at Stanford University, where his thesis work on the early universe was supervised by the cosmologist Andrei Linde. Following his doctorate he held a postdoctoral fellowship at the Canadian Institute for Theoretical Astrophysics in Toronto before joining the physics faculty at Smith College.

Research

Felder's research has focused on inflationary cosmology and the use of computational simulations to study complex physical systems, including the evolution of the early universe and wave propagation. Much of his work concerns preheating and reheating, the processes by which energy is transferred out of the inflaton field into other particles at the end of cosmic inflation.

Working with Igor Tkachev of CERN, Felder developed LATTICEEASY, a C++ program for performing lattice simulations of interacting scalar fields in the expanding universe. The program has been used in numerous early-universe cosmology projects and is distributed freely online with documentation. In November 2007 he released CLUSTEREASY, a parallel-computing version of LATTICEEASY for use on computer clusters. He has also developed the related tools FFTEASY and CURVEDLAND.

More recently, Felder's interests have included "quantum chaos," the question of whether chaotic behavior arises at the quantum scale of atoms and particles. He has emphasized that many of these computational problems are accessible to undergraduate students at various levels.

Popular science writing

As a hobby, Felder writes expository papers on scientific topics intended to be accessible to readers with no mathematics or science background. These papers are hosted on the Math and Physics Help Home Page maintained by his brother, Kenny Felder, some of them co-authored with him:

• The Expanding Universe — an introduction to the big bang model of the universe, including what it means to say the universe is expanding and what is meant by "The Big Bang."
• Beyond the Big Bang: Inflation and the Very Early Universe — a discussion of problems with the standard big bang model and how cosmologists address them with the theory of inflation, which supplements rather than replaces the big bang model.
• Quantum Mechanics: The Young Double-Slit Experiment — co-authored with Kenny Felder, an introduction to the basic concepts of quantum mechanics using the double-slit experiment to illustrate wave–particle duality.
• Quantum Mechanics: What Do You Do with a Wavefunction? — another collaboration with Kenny Felder, aimed at readers with a physics background who want help synthesizing the ideas and mathematics of quantum mechanics.
• Spooky Action at a Distance: An Explanation of Bell's Theorem — an outline of Bell's proof that the experimental results of quantum mechanics require that particles can instantly affect one another at large distances.
• Things Fall Apart: An Introduction to Entropy — an explanation of what entropy is and why it always increases, and thus why some natural processes are irreversible.
• Bumps and Wiggles: An Introduction to General Relativity — an introduction to basic ideas of Einstein's general theory of relativity, including curved spacetimes and black holes, best read after Kenny Felder's companion paper on special relativity.

Felder also gives frequent public talks on astronomy, cosmology, and modern physics, and created a 12-lecture video course on the early universe for The Great Courses.

Books

• Gary N. Felder and Kenny M. Felder, Mathematical Methods in Engineering and Physics (Wiley, 2016).
• Gary N. Felder and Kenny M. Felder, Modern Physics (Cambridge University Press, 2023).

Abstracts

• 2007 - "Spooky Action at a Distance: An Explanation of Bell's Theorem"

External links

• Gary Felder faculty page at Smith College
• Gary and Kenny Felder textbook website