What does a theoretical physicist do?

In this video I answer a question that I get a lot: "What does a theoretical physicist do?" How does it work? Do we sit around all day and dream up new particles?

Theoretical physics is a job very similar to any other. You get an education and then you put your knowledge to work. In physics as in all disciplines in science, most of the research is understanding what other people have done. But physicists do many other things besides their research: They teach, mentor, organize conferences, sit in committees, do public outreach (!), or perform administrational functions.

Where physics is special is in the amount of mathematics that we use in our work.

[aplacefaraway]

"What does a theoretical physicist do?" This is one of the many unsolved problems in physics.

[bobtimster]

Einstein was once asked by someone, who apparently did not know what theoretical physics was, where his laboratory was. He proudly held up his pencil. Another time he was asked what his most useful tool was. His response was that it was his wastebasket.

[MICHAELYEPES]

"Physics is the only thing you can really understand; it's the rest of the world that doesn't make sense."

[Thulesmann]

Physicists and Mathematicians have my highest respect. They are at the cognitive upper limit of human intelligence at this point in our evolution. I have a sense of awe when I contemplate their high intellects and their self-discipline, work ethic and ability to focus, and their idealistic hunger for the knowledge that can create a better world for all of us.

[bhangrafan]

Years ago I worked in Universities doing molecular biology research, but there were physics and maths departments in these places, and I always loved these subjects. What I saw of the physicists (theoretical ones) was each was locked in a little tiny office with a desk and a computer, and spent all day on the computer running simulations and doing calculations. It seemed a very isolated life compared to experimental work in a large open plan laboratory complex.

[donald-parker]

From the great philosopher YB: "In theory, there is no difference between theory and practice - In practice, there is."

[angelgavieiro]

I loved the final statement... that must be the reason why I watch physics youtubes, they make sense in comparison to the rest of my day... even when I am not fully (or even partly sometimes) understanding them!

[manoo]

The problem is that almost no one (outside of the field of science) understands what a 'theory' means. Almost everyone (i.e the public) think its just an 'idea' you came up with that day!

[captainoates]

Sabine is the best at the public outreach part. My presence here is living proof.

[sergeyyatskevitch]

Great insight, especially about the importance of being good at Math (diff equations, group theory, stochastic systems, etc.). This is why you can meet theor physicists anywhere from the Perimeter Institute to the high-frequency trading shops. To rephrase, learning math is more interesting than learning how to code. Although the latter is needed as well. Cheers!

[musicalBurr]

Nice work Sabine! Save the best comment for last! (Eminently quotable) You are a great performer and know how to put on a good show, setting aside your math and physics prowess. I get so excited when I see there's a new video from you - never disappoints! Thanks again. James.

[skydebnath]

The last line made my day... It gave me a confirmation that I am on the right track.... Thank you very much

[olivierjung]

Frohe Weihnachten und rutsch gut ins Neue Jahr mit deinen Lieben ; )

[ivanfromunion]

Me: "You have me! I AM GOING TO BECOME A THEORETICAL PHYSICIST!"

Sabine: "You get an education" and "You have to understand the mathematics"...

Me: "AS SOON AS I FEED THE CAT."

[MichaelZeng-hnmy]

Sabine Hossenfelder explaination on theoretical physicists do is clear n amazing. She is one of the finest best teacher lecturer in the sciencetific areas. She should appeared more on the internets channels will assist young sciencetists to think widely on physics. I always watch her programmes with alots of intesrests in physics.

[richardduke]

Sounds easy ! Read books, go to meetings, talk to people - but you have to be able to connect the dots between all of that information .

[dominiksrokowski]

Merry Christmas! and well deserved holiday! Please bring us more of you next year!

[kenmcnearny]

The concepts of physics seem intuitively easy to understand oddly though I find the mathematics impenetrable. Oppositional movements of discrete bodies evolving into vectors of motion as they effect one another are easy and pleasant to visualize mentally but the math goes down like a sandpaper sandwich. Funny how people are different like that. And thank you for evoking a pleasant memory of a co-worker and doctoral candidate explaining that writing a doctoral thesis is as simple as taking a body of knowledge and rearranging it in a unique way. Anyone can do it really (not their first day of course) she said with a smile.

[thePronto]

So being a theoretical physicist is very similar to running a business. You have to understand what has already been done, separate out what hasn't been done and figure out what you can get done with your limited resources. The two things I think you left out, in both domains :-) are: figure out what you can get funding for, and figure out if anyone is going to be interested. They might be the same thing, but not always.

[ctrc]

it's the rest of the world that doesn't make sense :D :D :D on point!