What is the Smallest Thing Possible? [ft. Everything Science]

Things in our universe are get really small. So small that the sizes very quickly become unimaginable. Asking what the smallest thing that we know of is is an interesting question to consider. But an even more interesting question is what the smallest thing possible is. The answer blends together quantum mechanics, special relativity, and general relativity in an incredible way.

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[ikiseikel]

"Ignoring the factor of 2..."
Pay attention here students, this is a key technique in theoretical physics.

[silentbubble]

Am I thinking this right? You can always change your frame of reference to the rest frame of the electron so that the energy is just the rest-mass energy. But the electron cannot be completely at rest since there's uncertainty in the momentum, which is related to the uncertainty in energy. So it's not the energy that creates particles, instead, it's the uncertainty in energy that does?

[Higgsinophysics]

ah yes quantum smearing. We should use that term much more :D Epic collab !

[rebeccahaber]

came over from Everything Science, great video!

[deviprasadpalli]

Sir can u. Clarify my doubt...
Can virtual particles travel faster than light in a vacuum

[kanedawong]

that protons and neutrons and electrons thing reminded me off bill wurtz the history of the world vid at the start

[peterfireflylund]

Schwarzschild = Schwarz + Schild = black + shield. It is NOT Schwarzs + child.

[alienzenx]

You said that the uncertainty of the mass is zero, but this is technically only true for stable particles. I guess for small mass particles this would be small compared the the momentum uncertainty, but if you made a fundamental particle really massive, it would become extremely unstable(assuming you didn't give it some weird property that prevented it's decay to other particles) and the uncertainty in it's mass would get really big I guess. Just a thought.

More importantly though, how does this argument apply to massless particles? A photon clearly has a non zero uncertainty in its energy, which is larger than its mass.

[beastlybuickv]

"...our caveman minds..." 😂😂😂😂😂

[FulgenceMalvenue]

Interesting video, as usual.

I have to make a picometre correction though:
At 1:50, ℏ is the reduced Plack constant, also called the Dirac constant. It is equal to the Planck constant divided by 2π
So we have: ℏ = h/2π