Real Life Examples of Physics Theories

[PRodQuanta]

What are some real life examples, connections to some, or your favorite, past or present, physic's theory.some choices are-Newton, relativity, quantum theory, or even galileo's theories.

(i.e.-S.Relativity_The atomic bomb.)
Thanks
Paden Roder

 

[revesz]

well there's the fact that I am sitting here, and I am being pushed downwards by some strange force called gravity, but then again nobody really knows what gravity is, so then that's not much of an example

 

[Janitor]

I'm not sure what my favorite branch of physics, or my favorite theory is. But I can tell you what I would like to be able to fully understand right now. Non-relativistic quantum mechanics can't very well handle particle creation and annihilation. Relativistic quantum field theory does the trick. There is a good bit of talk in RQFT about "second quantization," which involves creation and annihilation operators which change particle occupancy number. Renormalization is another topic which comes up in RQFT. It looks like a steep road to climb, to understand it all in detail. I would be curious to hear which members of the Forum have mastered that material.

 

[HallsofIvy]

Back when people first build radios, they used "crystals" without really understanding how they worked. Then switched to tubes, then to transistors. Transistors are really just "crystals" that we (well, the scientists and engineers) understand better because of quantum physics.

 

[selfAdjoint]

I just finished reading the biography of John Bardeen, "True Genius". Both he and Brattain had been radio amateurs as teenagers and were familiar with crystals and probing for the sweet spot. A lot of their experience with that went into their experiments with the transistor effect. They didn't really understand it at first, and only gradually conceptualized what was going on (this was primarily Bardeen's contribution) as they saw more particulars of the effect.