What we’re about
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 (4+)
See all- Advanced study group: Quantum Field TheoryLink visible for attendees
To prepare for October 6th meeting: See bottom of this event description.
This is an advanced study group for folks who are committed to learning quantum field theory rigorously. Everyone with an undergraduate background in math or physics is welcome to attend. Before you sign up, please make sure you’re comfortable with multivariable integration, partial differential equations, and other concepts taught in upper division undergraduate courses. If you’re not able to dedicate time between each session to work on problems, this is not the event for you.
Our primary text is Anthony Zee's Quantum Field Theory in a Nutshell. Each weekly meeting consists of a review of the material we studied, followed by problem-solving and open discussion. In addition to the live group discussions over Zoom, we also maintain a chat server for staying in touch between meetups. Ask us for a link.
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October 6th agenda:- We are reviewing section 1.4 today. Please re-read sections 1.1-1.4 thoroughly and come prepared to discuss them in detail.
- Solve any exercises in sections 1.2-1.4 that you haven't yet tried: I.2.1, I.2.2, I.3.1, I.3.2, I.3.3, I.4.1
- Weekly Open Self-Study & Office Hours for Previous AttendeesLink visible for attendees
This is a weekly Zoom meeting (see below for link) for anyone who's already attended our previous meetups to have (mostly-)quiet self-study time on any topic in physics or math. The goal is to recreate the feeling of being in the same study room together, just like in college. So leave your camera on! You may come and go at any time during study hours.
Unlike our other events, this is not a facilitated or structured event and there is no specific topic of study. Sometimes people may decide to work on the same topic together, and other times everyone will be reading or solving problems on their own.
Although this is primarily a quiet study session, talking is allowed as long as it's on the topic(s) of study and with the purpose of asking a question or helping someone. Otherwise, please be courteous and respectful of other people by leaving your microphone off.
This event complements our other meetups, which are subject-specific, structured learning environments.
If you are new to Physics With Friends, before coming to this quiet self-study event we ask that you please come to one of our other meetups first so that we can get to know one another.
*** ZOOM LINK ***
The Zoom meeting URL is a pinned message in the #study-buddies channel. If you don't know what this means, it's because we haven't met you yet. Please come to one of our meetups and we'll help you get set up. - Relativity and Differential GeometryLink visible for attendees
(If you've been here before: See below for October 8th suggested homework.)
Join us for an open-ended, recurring discussion & study group for the theory of relativity, both special and general, and differential geometry. There isn't a specific agenda, timeline, or textbook. Some of us are reading through Guidry's Modern General Relativity and Needham's Visual Differential Geometry and Forms, and the classic Gravitation by Misner, Thorne, and Wheeler. Others are using their own favorite books and other resources. Our goal is to exchange the bits & pieces that we know with one another and to discuss & try to find answers to our questions using whatever methods we want.
If you have just found this event and are worried that you're too far behind, don't worry! Our meetups are expressly structured to encourage and invite people to join us at any point and at any level of prior knowledge, as long as you've had at least some exposure to calculus and basic physics in the past. You are definitely welcome here!
We also maintain a live chat server for staying in touch between meetups. Ask us for a link.
This event is one of the many other collaborative study tracks in our Physics With Friends community. Check out all of our other events to find additional physics topics that you might want to study together!
Please note that the Relativity & Differential Geometry meetup series is a highly mathematical meetup for everyone who is serious about learning the advanced branches of math and physics that one needs to master in order to deeply understand the equations and applications of relativity. 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.
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Suggested homework for October 8th:- Read Needham chapters 8 and 9
- Solve Needham problems III.1, III.2, III.4
- See the below list for more suggested problems in Guidry and/or Needham that correspond to materials that you've already read.
IF YOU ARE NEW HERE: Just come! Don't worry about any of this.
Here is a running list of problems we've previously solved. You're encouraged to do these if you're not sure which ones to choose yourself. This way you can discuss your approach and solution with others who can offer guidance.
––– Modern General Relativity (Guidry) –––
- Chapter 2: 1 through 6
- Chapter 3: 1, 2, 8, 11, 19, 23, 24
- Chapter 5: 11
- Chapter 6: 1, 2
- Chapter 7: 3, 4, 5, 6, 13, 18
- Chapter 8: 1, 2, 5
- Chapter 9: 1, 2
––– Visual Differential Geometry (Needham) –––
Act I (problems in Chapter 3)
- 1 or 2 or 3; 5; 6; 8; 14
- Use 3D graphing software, a 3D printer, a bowl of fruit, or any other visual aid to get a gut feeling about geodesics and Gaussian curvature.
- (Just for fun: Problem 4 :-))
Act II (problems in Chapter 7)
- Chapter 4: 1, 4, 10, 13
- Chapter 5: 15, 16, 17, 18, 23. Also, explain why the geodesic on the pseudosphere maps to a semicircle.
- Chapter 6: 27, 28
Act III (problems in Chapter 20)
- Chapter 8: 1
- Chapter 9: 2, 4
Act V (problems in Chapter 39)
- Chapter 32: 2, 3
––– Projects created by our members –––
- Project #1 if you've read up through Guidry chapter 7: Choose a (simple) 2D curved surface and graph its embedding in 3D space. Find its line element, metric, and Christoffel symbol using whatever coordinate system makes your life easiest. Inspect the elements of the Christoffel symbol for each upper component and see if you can develop an intuitive feel for their meaning. What would happen if you changed your parametrization of the surface slightly (e.g., add or multiply one of the components by a constant)? Can you predict how the change of the 3D graph of the surface correlates to the changed values of the Christoffel symbol?
- Project #2: Draw (or imagine) the Earth as a sphere. Choose a ring of latitude between the equator and north pole. How does a vector change as it is parallel-transported all the way around this ring? Compare the vector before and after in the tangent space of the starting point. If you can code, make an animation that shows this process.
