🌟 Fun Fact: Louis de Broglie was not just some boring scientist! He was a French aristocrat! Think of him as the cool royal dude with a big physics brain!

• Einstein explained photoelectricity (think about how light can push electrons off a surface).
• de Broglie took this idea and thought, "Hey, what if particles like electrons also acted like waves?"
• This became the de Broglie Hypothesis: electrons and particles might act like waves under the right conditions.

🎈 Real-World Example: Imagine you're both a student by day (particle) and a rockstar by night (wave). Different situations bring out different sides of you!

• Electrons behave like standing waves (kinda like the strings on a guitar).
• This idea? Yep, it's from de Broglie's work!

• Main Takeaway: Energy (E) and mass (m) are basically the same thing! Like two sides of a coin.
• For moving particles, there's a more complex equation, but the main part is energy is tied to mass and momentum.

• Photons = Light particles with zero rest mass (they're the ultimate lightweights!).
• They have a relationship between energy, momentum, and wavelength. It's like their secret handshake!