It's Time to Say Goodbye to F = ma...

 And Discover the Power of the Lagrangian!

If you're reading this page, you probably know a fair bit about F = ma.

You know that Isaac Newton wrote it down 300 and some years ago, when he basically founded modern physics.

And you know that you can use it to describe the motion of everything from a home run soaring out of a baseball stadium to Earth's orbit around the Sun.

Here's the thing though...

Outside of freshman physics classes, F = ma is barely relevant for most of the deepest things we've understood about physics in the past century.

Seriously: if you open up almost any physics textbook about the most fundamental laws of nature, you'll hardly find F = ma mentioned anywhere at all!

Instead of familiar words like "force" and "acceleration," you'll see things like "Lagrangian" and "least action" and "Euler-Lagrange equation."

It's as if higher-level physics is written in a completely different language! And if you don't speak the lingo, it's all a bit overwhelming.

Why didn't your intro physics classes prepare you for this!?

The fact is, in the years after Newton, a different approach to physics was discovered that's proven to be better in almost every way.

It's called the Lagrangian formalism.

And if you want to study any of the lion's share of modern physics topics, including...

✅ Field theory

✅ Particle physics

✅ Quantum mechanics 

and many more, you're going to need to learn the Lagrangian way of doing things.

It's an essential subject for understanding higher-level physics.

Good News, & Not-So-Good News

The Lagrangian formalism historically began as a new approach to classical mechanics.

And that's exactly where you should start learning about it, too.

The good news is...

Lagrangian mechanics isn't just some boring prerequisite that you have to trudge through to get to the really cool physics.

It's absolutely fascinating in its own right.

The bad news is...

Lagrangian mechanics tends to get a reputation for being one of the hardest subjects in a physics student’s curriculum.

Part of the reason is that it's just so different from what you've learned before.

Again—you start out learning physics using an equation so famous that it's difficult to find anybody who doesn't know it by heart:

$$\vec {F} = m \vec {a}.$$
Meanwhile, the central equation of Lagrangian mechanics looks like this...

$$\frac{\mathrm{d}  }{\mathrm{d} t } \frac{\partial  L}{\partial \dot q } = \frac{\partial  L}{\partial q }.$$
What!? How are these two things supposed to describe the same universe?!

Honestly, this equation is just plain scary the first time you see it.

What the heck is $q$, or $\dot q$, or $\partial L/\partial \dot q$?

Like I said: it looks like a completely different language.

And it's no wonder you might come away thinking the Lagrangian formalism is ridiculously harder!

But the thing is...

Nothing Could Be Further From the Truth

The truth is that the Lagrangian formulation of mechanics makes most problems simpler to solve.

That's because F = ma is a PAIN—for all but the most basic setups.

You have to deal with vectors and "fictitious forces" and jump through crazy hoops if you want to solve a problem using anything but x, y, z coordinates.

The Lagrangian approach does away with all that nonsense. It boils the whole problem down to taking a few derivatives.

Seriously, if you know how to take a derivative, you're basically ready to take on Lagrangian mechanics.

And what you'll discover is how much easier it makes solving problems that would bring tears to your eyes to tackle using F = ma.

That's why I've created a course to guide you through a tightly focused introduction to Lagrangian mechanics:

I'm going to show you just how powerful (and not scary!) the Lagrangian approach actually is.

The course is for you if you’ve studied calculus and Newtonian mechanics, and you're eager to delve deeper into the fundamental principles of physics.

Hello! I'm Dr. Elliot Schneider 👋.

I've been studying physics for about two decades—and teaching it almost as long. I did my PhD in physics at Harvard and before that my BS at Caltech. 

I love physics, and I especially love teaching physics. Traditionally, the best physics classes have been reserved for students at elite (and expensive) universities.

That's why I'm working to make exceptional physics courses like this one available online!

There's So Much More to Physics

If the Lagrangian formalism were only about making classical mechanics problems easier to solve, that would already be enough of a reason for you to learn it.

But it's about so much more than that.

And there are more important reasons why F = ma barely appears in higher-level physics.

One crucial reason is that Lagrangians reveal profound features of physics that are much harder to see in Newton's approach—like the deep connection between symmetries of nature and conservation laws. 

For example, in your first physics class you learned that energy is conserved for, say, a ball flying through the air or a block attached to a spring. 

But you might have wondered why this particular thing, $E = \frac{1}{2} m \left( \frac{\mathrm{d}x}{\mathrm{d}t} \right)^2 + U(x)$, should be a constant. Where does the conservation law come from?

Lagrangian mechanics gives the answer: energy is conserved because of a symmetry—in this case, the fact that the laws of physics don't change with time.

But the deepest reason why you need to move beyond F = ma is this:

The most fundamental laws of the universe are quantum in nature.

And in the quantum world, F = ma is almost completely irrelevantwhile the Lagrangian formalism (and its close cousin, the "Hamiltonian formalism") become absolutely essential.

That's why, if you really want to understand physics, you're going to need to learn the Lagrangian approach.

And after you take this course—when you’re holding the power of the Lagrangian in your hands—you’ll look back and laugh at your early days in physics with nothing but F = ma in your arsenal!

It's like becoming a Jedi and trading a wooden stick in exchange for a lightsaber.

By Taking This Course, You'll Learn...

… how the core principle of Lagrangian mechanics—the principle of least action—transforms the way we look at almost everything in physics.

the key ideas behind the equations of Lagrangian mechanics, so that you know not only how to apply them but also what they mean.

… the deep connection between symmetries and conservation laws that you’ll encounter again and again in every physics topic you study from here on.

… the 3-step Lagrangian procedure to analyze almost any physical system, so that you never have to deal with F = ma again.

… how to solve physics problems by choosing coordinates that work for you instead of against you.

… the math behind the calculus of variations, and how to apply it to minimax problems in physics and beyond.

… how to avoid the classic pitfalls of F = ma, by following a foolproof procedure that takes care of all the tricky parts automatically.

… how to turn complicated equations into simple ones by linearizing them with Taylor series.

… to develop key skills that experienced physicists apply every time they solve a problem.

… fundamental concepts that are essential prerequisites for studying more advanced topics in physics.

And all at a fraction of the cost of a traditional college course.

Without the stress of final exams, grades, or deadlines!

Clips From The Course

The Average College Course Costs $4095

The average cost of a course at a private US college is over four thousand dollars.

And as any college student can tell you, the teaching is… hit or miss.

Hopefully, you’re here because you already know from my YouTube videos, notes, and newsletter that my teaching style clicks with you. And you’re ready to join me on a carefully plotted route through the fundamentals of Lagrangian mechanics!

(And at a much slower pace than in a 20-minute YouTube video!)

Besides, what if you’re not currently a college student and you still want to learn physics?

Maybe you're a lifelong learner pursuing a previously unfulfilled passion for physics.

Or you might be a highly motivated high school student who’s covered Newtonian mechanics and calculus and is eager to take on a new challenge.

(That was me many years ago, after I had finished all the physics courses my high school had to offer and couldn't wait to devour more. I wish I could have taken this course!)

Or maybe you are a current college student, and you're looking to get a leg up in preparation for a tough class next semester.

Then as long as you’re prepared to put in the effort it takes to master this material, this course is for you!

And it will transform the way you think about physics from now on.

14 Day Money-Back Guarantee

I want you to love this course—and come away from it loving Lagrangian mechanics too. If you start the course and find that it's not quite the right fit for you, just send me a message within the first two weeks to return it for a full refund. No questions asked.

What Students Have Said About The Course

Challenging, but not Mystifying

In this class, I’m going to lead you through a focused introduction to the essentials of Lagrangian mechanics.

Over the course of about 11 hours of lessons, 5 hours of problem-solving sessions, and 5 practice homework sheets, you’ll discover how much simpler Lagrangians make it to solve problems—and the insights this new point of view teaches us about the universe.

But don’t mistake that statement to mean that Lagrangian mechanics is easy.

You should know going in that this is challenging material (like anything worth learning).

But I'm going to be there as your guide, explaining all the key ideas and equations, and solving a ton of example problems along the way.

And you’ll come away from this course with

✅  a much deeper understanding of the laws of nature

✅  a practical toolset for solving problems

 the preparation to take on even more advanced physics

And maybe the best part of all is...

There are no grades in this class!

No quizzes, no midterms, and no final exams.

We’re here to learn purely for learning’s sake—which is the best kind of learning.

Of course, the FLIP side is that it’s up to you to stay committed to putting in the work and completing all the lessons and assignments.

But if you’re a highly motivated student, this course will give you the tools to succeed.

Optional Add-On: 1-to-1 Coaching Support

An online course has A LOT of advantages over a traditional one.

📅 You can complete the lessons on your own schedule.

🏠 You can attend from the comfort of your own home.

⏯️ You can pause, rewind, and rewatch.

(I can't tell you the number of times I'd wished I had a remote control to pause or rewind a professor's lecture during classes I took in college!)

There’s one major disadvantage, though.

And it's that I’m not there with you in class to answer your questions.

That’s why I’m offering an optional add-on for 1-to-1 Coaching Support:

Due to the number of students taking the class at once, it unfortunately won't be possible for me to give detailed question and answer support to everyone.

But with the 1-to-1 Coaching add-on, I’ll be available to answer your questions as you progress through the course.

Any time you...

🙋 get stuck on a problem...

🙋 get confused about an equation...

🙋 need help understanding any concepts from the course...

you'll be able to send me a message, and I'll help as soon as I can.

I can only provide 1-to-1 Coaching Support to a limited number of students at a time, however, so please be aware that this offer may sell out.



  • 16 hours of lesson videos
  • 60+ pages of example problems and solutions
  • Lecture summary sheets
  • 14 day money-back guarantee
Click to Enroll



  • Full course
  • 1-to-1 question & answer support
  • 14 day money-back guarantee
Click to Enroll

If you're not sure yet if the course is right for you, take a look at the FAQs below, and also feel free to write to me at [email protected] with any additional questions.

Frequently Asked Questions



  • 16 hours of lesson videos
  • 60+ pages of example problems and solutions
  • Lecture summary sheets
  • 14 day money-back guarantee
Click to Enroll



  • Full course
  • 1-to-1 question & answer support
  • 14 day money-back guarantee
Click to Enroll

If you have any additional questions about whether the course is right for you, feel free to write to me at [email protected].

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