What is quantum tunneling?

Transcript: http://www.davidcolarusso.com/blog/?p=33#more-33

This video is an adaptation of an earlier piece of mine--Perspective on quantum mechanical tunneling. That film, however, was designed for a unique audience, and I felt its overall length was limiting its appeal here. So I've repackaged it as one of my Explainer episodes. I Hope you enjoy.

People have been asking for the math. So here it is. The Sun's core temp is ~13.6 MK. For hydrogen nuclei the Coulomb barrier is roughly 0.1 MeV. This corresponds to a temperature in excess of 1 GK! Luckily, tunneling and the distribution of speeds among nuclei lower the actual temperature required. So without tunneling even the Sun's core isn't hot enough for fusion. To see most of this worked through, check out this link:
http://burro.cwru.edu/Academics/Astr221/StarPhys/coulomb.html
for a less mathematical explanation, try:
http://en.wikipedia.org/wiki/Nuclear_fusion#Requirements

The Tabletop Explainer is an intermittent educational vlog presenting answers to viewer questions, brief science lessons, and ideas for teachers and students. It is a feature of my blog "Tilts at Windmils" which can be found at http://www.davidcolarusso.com/blog/

Category:

Education

Tags:

• physics
• quantum
• mechanics
• tunneling
• fusion
• potential
• energy
• star
• reality
• uncertainty
• principle
• measurement
• probability
• cloud

[Arghira]

Knock knock. -Who's there? Quantum tunneling. -Quantum tunneling wh --- Nevermind, I'm already inside.

[shaygahweh]

Chuck Norris can tunnel through a mountain with a probability of e^ -(2awesome/spitting distance)

[taejamhaha]

well, Einstein may just have uncovered the portion of the principles God used in creatingthe universe. Like finding the quadratic equation by the given vertex and a point?

[tjdrummond178]

I really enjoyed this video. Could you direct me to a reference which explains why the pressure and energy density isn't high enough in the sun's core to overcome the electrostatic repulsive forces? I'd like to read up on this a bit. Thanks.

[Brockhad]

Can this also exist with different vaccua? I'm curious about the big bang and also topological surgery.

[Zandonus]

There's no uncertainty, just Consciousness. If you are feeling a lot of change in YOUR worldview, you are simply shifting through realities. I ''Believe'' That there are forces that are in control of the Sun, doing the right thing. Just doing whatever it feels to be the right thing to do, to give the earth light without Harming it.

[Zandonus]

@shaygahweh The thing is that YOU can do it.

[SNAKEPATR10T]

@thechoreographer That is true, but there are some models in which the pair pops into existence at the event horizon and one of them may tunnel outside of it.

[thechoreographer]

@SNAKEPATR10T Quantum tunneling is not involved in Hawking radiation. Virtual matter-antimatter particles pop into existence the event horizon of a black hole. Normally they would annihilate each other. But at the event horizon, one gets sucked in while the other escapes. At least that is the most common interpretation of Hawking radiation.

[feynmanmagnets]

@alotoaltosaxes Lasers couldn't exist without a thorough mathematical understanding of quantum mechanics. Same with just about every electronic device created.

[12ryryr345]

@alotoaltosaxes Watch the Sixty Symbols video on Quantum Tunneling They talk about touchscreens! :)