About us
This is a group for anyone who has ever rigorously studied physics – or has wanted to. Here's why you'd want to join us:
- If you feel like physics is the most interesting and most difficult subject that there is;
- If you're burning with a desire to deeply understand the universe at its smallest and largest scales;
- And if you thrive in an environment of learning through collaboration with people like yourself...
... then you've found the right place!
Join us to participate in lively discussions and learn core material in serious study groups. We offer multiple tracks of study, regularly host special events and talks, and are constantly tweaking the meetup to make it more useful. We also stay in touch between meetings to motivate and help each other continue learning.
Everyone is welcome from every level of experience! Many of us are (re)discovering physics after college (sometimes long after) and it can be easy to feel rusty or underqualified. Don't fall into that false narrative! If you think some of the material in this meetup is too advanced, we want you to join us so that we can help you learn!
Upcoming events
105
Physics Essentials: Modern Mechanics
·OnlineOnlineJoin us in a guided group study of the most essential subject in physics: mechanics! Unlike your high school or college mechanics course, we're following two deeply insightful textbooks:
- Modern Classical Mechanics, by Helliwell and Sahakian, is our primary text. It offers a fresh take on classical mechanics, treating it as a logically coherent system rather than a bag of tricks. It introduces powerful tools like the Euler-Lagrange equations and Hamiltonian dynamics without assuming a deep math or physics background. The authors focus on the “why” behind the equations, helping readers see the physical ideas and symmetries that unify different problems.
- Mathematical Methods of Classical Mechanics, by V.I. Arnold, emphasizes the deep, geometric language of physics. We use this as a secondary resource. Arnold’s approach connects simple Newtonian mechanics to powerful ideas like manifolds, symplectic structure, and group theory – concepts that also show up in quantum mechanics and modern physics.
The material starts with familiar concepts and carefully develops them into advanced topics. Don't worry if you feel like you don't have enough background for the latter; our group is incredibly friendly and paced to support learners from a variety of backgrounds. We encourage questions, discussions, and a spirit of curiosity. Whether you're revisiting physics or exploring it for the first time, you're welcome here.
What to expect – Here is our current format:
- Before each meeting, we will assign ourselves a reading and a set of exercises that everyone is invited to try for next time. (All of this is optional and there is never anything expected or required – this is a self-study group!)
- During the meeting, one or more volunteers will teach the lessons from the assigned readings, and others will present their solutions to (or attempts at!) the exercises.
- Between meetings, we will collaborate through our chat server and/or small study sessions during "office hours". New members should especially take advantage of these to get up to speed. Ask us for details and links to these fantastic resources!
Prerequisites: So long as you have taken at least some amount of college calculus and physics at some point in your life, you should be fine.
We maintain a live chat server for staying in touch between meetups. Ask us for a link.This event joins our other existing collaborative study tracks. Please note that this particular meetup series is a highly mathematical meetup for everyone who is serious about learning field theory at a graduate or advanced undergraduate level. It is not a general discussion group for popular physics topics or sci-fi tangents. For casual physics chat, please attend our regular Discuss Physics and Make Friends event, held every third Wednesday of the month.
Having technical trouble joining the meeting? You need to use the Zoom app and log in with a (free to create) personal Zoom account before you can join our meeting. You might not be able to join directly from a web browser if you can’t log in.
7 attendees
Quantum Gravity Explorations
·OnlineOnlineOverview
This is a collaborative study group dedicated to understanding the foundations, motivations, and current landscape of quantum gravity research. Our goal is to build a clear conceptual picture of why quantum gravity is challenging, what the major approaches attempt to do, and how they compare.Developing a coherent understanding of quantum gravity requires engaging with the mathematics. As such, we will work through explicit equations and derivations to understand how gravitational dynamics emerge, how quantum consistency constrains theories, and why certain results are unavoidable rather than assumed.
Participants should have a basic familiarity with the principles of quantum mechanics, quantum field theory, and general relativity, and be comfortable with the Lagrangian formalism of physical theories.
What to expect
- We assign readings, lectures to watch, and curated exercises prior to each meeting, which will be announced below.
- During the meetings, one or more of the volunteers will walk through the assigned materials and moderate the discussion.
- Additional discussion between meetings will take place on our chat server, where we can exchange solutions, notes, interesting and relevant articles, etc. Notes and solutions may also be hosted in our Github repository.
What this group is NOT
- Not a popular science or sci-fi discussion group.
- Not a high-pressure, exercise-heavy bootcamp.
- Not a forum to strongly endorse or air grievances against any one approach to quantum gravity .
For casual physics chat or general discussion, please see our other Meetup groups.
Community & Continuity
We maintain a live chat server for continuing discussions between meetups, and a link can be provided upon request if you’d like to join. This even is part of the broader Physics With Friends community, which hosts multiple collaborative study tracks across physics and mathematics.Materials & Assignments
For the next several meetings, we will be going through Barton Zwiebach’s A First Course in String Theory, 2nd Ed. (Amazon link).- Read Zwiebach Chapter 12, and attempt problems 12.3 and 12.4 This chapter is dense, so we will likely only make it through sections 12.1-12.4 in this meeting.
4 attendees
Differential Geometry: Curvature
·OnlineOnlineThis ongoing study group began in May 2026 as a guided reading of Visual Differential Geometry and Forms by Tristan Needham. The book develops differential geometry visually and conceptually, emphasizing geometric meaning before formal calculation.
We have now completed the first two Acts and most of Act III.
Act I — The Nature of Space
We began with Euclidean, spherical, and hyperbolic geometry; geodesics as the straightest possible paths; intrinsic versus extrinsic geometry; and Gaussian curvature as something that can be detected through measurements made within a surface.
Act II — The Metric
We then studied how the metric encodes infinitesimal distance and determines the intrinsic geometry of a surface. Along the way, we explored conformal maps, stereographic projection, the pseudosphere and hyperbolic plane, Möbius transformations, isometries, and Needham’s first bridge from geometry to Einstein’s spacetime.
Act III — Curvature
In our last two meetings, we covered Chapters 8–11:
• Curvature of plane curves
• Curves in three-dimensional space
• Principal curvatures of a surface
• Geodesics and geodesic curvatureThis meeting will complete our focused route through Act III with:
• Chapter 12 — The Extrinsic Curvature of a Surface
• Chapter 13 — Gauss’s Theorema EgregiumWe will study the spherical map, see how the two principal curvatures combine to describe the local behavior of a surface’s normal directions, and reach Gauss’s remarkable discovery:
Gaussian curvature, although first constructed from how a surface bends in space, is completely determined by the surface’s intrinsic metric.
This is one of the central turning points in differential geometry and an essential idea behind General Relativity.
About the Image
The image shows a saddle-shaped surface with its principal directions, normal vectors, and Gauss map to the sphere. The principal curvatures combine to give the surface’s Gaussian curvature.
Gauss’s Theorema Egregium reveals the remarkable result: although Gaussian curvature is first described through how a surface bends in space, it is determined entirely by the surface’s intrinsic metric.Where We Go Next — Act IV: Parallel Transport
Our goal is to follow the most direct conceptual route through Needham’s book toward the Einstein Field Equation.
In Act IV, we will study:
• Parallel transport and the covariant derivative
• Holonomy around closed loops
• A deeper explanation of the Theorema Egregium
• How the metric determines curvature
• The Jacobi equation and geodesic deviation
• The Riemann curvature tensor
• The Ricci tensor
• Einstein’s curved spacetime
• The Einstein Field EquationThe physical bridge is geodesic deviation: curvature causes neighboring freely falling paths to accelerate relative to one another. In General Relativity, this becomes the observable tidal effect of gravity.
What to Expect
• Discussion-based format rather than a formal lecture
• Visual and conceptual emphasis
• Calculus and mathematical curiosity recommended
• Selected calculations, examples, and demonstrations
• Participants ranging from interested beginners to experienced physicists and mathematicians
• Questions and alternative explanations are encouragedSchedule
This group meets every two weeks, alternating with our companion study group on The Road to Reality.
New participants are welcome at any time. Each meeting includes enough review and context to help participants join the discussion even if they have not attended every earlier session.
More in Physics With Friends
This event is one of several collaborative study tracks in the Physics With Friends community.
Explore additional meetings here9 attendeesPhysics Essentials: Modern Mechanics
·OnlineOnlineJoin us in a guided group study of the most essential subject in physics: mechanics! Unlike your high school or college mechanics course, we're following two deeply insightful textbooks:
- Modern Classical Mechanics, by Helliwell and Sahakian, is our primary text. It offers a fresh take on classical mechanics, treating it as a logically coherent system rather than a bag of tricks. It introduces powerful tools like the Euler-Lagrange equations and Hamiltonian dynamics without assuming a deep math or physics background. The authors focus on the “why” behind the equations, helping readers see the physical ideas and symmetries that unify different problems.
- Mathematical Methods of Classical Mechanics, by V.I. Arnold, emphasizes the deep, geometric language of physics. We use this as a secondary resource. Arnold’s approach connects simple Newtonian mechanics to powerful ideas like manifolds, symplectic structure, and group theory – concepts that also show up in quantum mechanics and modern physics.
The material starts with familiar concepts and carefully develops them into advanced topics. Don't worry if you feel like you don't have enough background for the latter; our group is incredibly friendly and paced to support learners from a variety of backgrounds. We encourage questions, discussions, and a spirit of curiosity. Whether you're revisiting physics or exploring it for the first time, you're welcome here.
What to expect – Here is our current format:
- Before each meeting, we will assign ourselves a reading and a set of exercises that everyone is invited to try for next time. (All of this is optional and there is never anything expected or required – this is a self-study group!)
- During the meeting, one or more volunteers will teach the lessons from the assigned readings, and others will present their solutions to (or attempts at!) the exercises.
- Between meetings, we will collaborate through our chat server and/or small study sessions during "office hours". New members should especially take advantage of these to get up to speed. Ask us for details and links to these fantastic resources!
Prerequisites: So long as you have taken at least some amount of college calculus and physics at some point in your life, you should be fine.
We maintain a live chat server for staying in touch between meetups. Ask us for a link.This event joins our other existing collaborative study tracks. Please note that this particular meetup series is a highly mathematical meetup for everyone who is serious about learning field theory at a graduate or advanced undergraduate level. It is not a general discussion group for popular physics topics or sci-fi tangents. For casual physics chat, please attend our regular Discuss Physics and Make Friends event, held every third Wednesday of the month.
Having technical trouble joining the meeting? You need to use the Zoom app and log in with a (free to create) personal Zoom account before you can join our meeting. You might not be able to join directly from a web browser if you can’t log in.
3 attendees
Past events
1205
