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2022-10-19: The Equation That Explains (Nearly) Everything!

  • 14:00: ... different particle masses, or chooses coupling strengths like the fine structure constant we discussed recently. And it doesn't explain dark energy or the ...

2022-10-12: The REAL Possibility of Mapping Alien Planets!

  • 15:45: ... one were we talked about the mysterious   meaning of the fine structure constant. AJMansfield asks whether JWST also have a   program for doing ...
  • 18:29: ... change the way the quantum fields behave - including raising the fine structure constant.   We routinely reach temperatures where the fine structure constant ...
  • 19:23: ... also be different during that time?   Well yes! The fine structure constant is defined as the electron charge squared divided by 4pi ...

2022-09-28: Why Is 1/137 One of the Greatest Unsolved Problems In Physics?

  • 00:19: This is the fine structure constant, and it appears everywhere in our equations of quantum physics, and we’re still trying to figure out why.
  • 00:30: ... fine structure constant, designated as the greek letter alpha, just looks like one of the many ...
  • 00:57: ... I die my first question to the Devil will be: What is the meaning of the fine structure constant?” Even Richard Feyman pondered its mysteries his entire ...
  • 03:45: This number just happens to be 1/137.035999, the fine structure constant.
  • 04:34: And that’s just the tip of the iceberg for the appearances of the fine structure constant in the laws of physics.
  • 05:55: And that’s exactly what the  fine structure constant is:   it’s the coupling strength of the electromagnetic force.
  • 06:23: So the Fine Structure Constant sets the  "strength" of the electromagnetic force.
  • 06:37: So it’s starting to make sense why the fine structure constant appears in all of these formulas that depend on the electromagnetic force.
  • 07:06: In fact the fine structure constant isn’t as constant as it sounds.
  • 07:30: We’re now at the bottom of the energy scale,  and the fine structure constant has bottomed out at 1/137.035999.
  • 08:33: ... universe  ended up with this particular   value for the fine structure constant or many of the other fundamental ...
  • 09:08: But the fact that the fine structure constant  has such a convenient value isn’t the weirdest thing about it.
  • 10:10: But the fine structure constant is unitless.
  • 10:27: That’s handy for interstellar communication, but it also tells us that’s something's -seriously- up with the fine structure constant.
  • 10:52: But these things don’t pop up in all these unexpected places like the fine structure constant does.
  • 11:50: But without any units, it's not immediately clear what kind of relationship the Fine Structure Constant represents.
  • 12:08: If the other constants of nature tie various physical parameters together, perhaps the fine structure constant is what ties those constants together.
  • 12:43: ... fact that this canceling gives the fine structure constant, and the fine structure constant also represents the relationship between ...
  • 13:15: ... it could be that the fine structure constant is not a physical constant, but a mathematical one, like pi, but perhaps ...
  • 13:51: ... called the fine structure constant  “one of the greatest damn mysteries  of physics” and Poetically ...

2022-08-03: What Happens Inside a Proton?

  • 05:14: ... 1/137 thing is the fine structure constant. It’s the coupling strength between the electron   and ...
  • 06:02: ... the strong coupling constant.   It is much higher than the fine structure constant, of order 1, though it depends on energy scale.   That’s what ...

2022-02-10: The Nature of Space and Time AMA

  • 00:03: ... that the speed of light has changed for example numbers like the fine structure constant are often considered more fundamental these are these unitless numbers ...

2019-11-11: Does Life Need a Multiverse to Exist?

  • 07:37: ... forces are set by the so-called coupling constants - for example, the fine structure constant for electromagnetism and the gravitational constant for ...

2018-08-15: Quantum Theory's Most Incredible Prediction

  • 04:42: The fine structure constant is named after this effect.
  • 11:20: ... from the QED calculations to a value for G, you also need to know the fine structure constant that I mentioned ...
  • 11:41: So it's really the relationship between the electron magnetic moment and the fine structure constant that we're verifying.

2017-09-28: Are the Fundamental Constants Changing?

  • 03:33: Perhaps the most promising example is the fine structure constant.
  • 03:50: We use the Greek letter Alpha to represent the fine structure constant.
  • 06:20: Well, the magnitude of this wavelength split depends very strongly on the fine structure constant.
  • 08:43: And there are many other potential systematic errors the could masquerade as a change in the fine structure constant.
  • 09:32: If the fine structure constant is changing, then it's not changing by very much.

2017-07-19: The Real Star Wars

  • 17:02: So the electric charge, which in turn depends on the fine structure constant.
  • 17:07: In fact, the probability amplitude added at each vertex is proportional to the square root of the fine structure constant.
  • 17:20: So that's the square root of 1/137 squared, which is just the fine structure constant, which is close to 1%.
  • 17:40: Onlynamelefthere thinks our videos "are good and stuff, but will unsubscribe if we "set the fine structure constant to 1/100" once more.
  • 17:53: You guys think you're so cool measuring the fine structure constant to better than 1 part in a billion.

2017-06-28: The First Quantum Field Theory

  • 10:01: It predicts the relative value of the fine structure constant to a precision of one part in a billion.
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