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Future Train Wreck: Mine or Modern Physics talk Next Thursday, Jan. 26

If you are in Cambridge, MA on Thursday, Jan. 26, you can see me live at MIT in room 3-270 from...

Holiday Physics Card, 2016

Just put them in the mail on December 24...It was a fun year of thinking, whether the idea is right...

Unified Mathematical Field Theory Talk

I gave a 15 minute talk at a local Americal Physical Society Meeting.  Here is the title and...

Holiday Card 2015

Here is my holiday card for 2015, a tradition of mine going back to 1990.  Enjoy.On the back...

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Doug SweetserRSS Feed of this column.

Trying to be a semi-pro amateur physicist (yes I accept special relativity is right!). I _had_ my own effort to unify gravity with other forces in Nature. It ran into quite a number of technically... Read More »

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RETRACTION: I have decided to retract three blogs (Deriving … 4/5, 5/5, 6/5+1). I was unable to figure out a reasonable statement concerning gauge symmetry. When the blogs were initially written, I focused on the field equations, mainly the Gauss-like law, and ignored the force equations entirely. Finding a solution that works with the the field and force equations were not looked for. A consistent proposal should do all three things (fields, forces, and solutions) with grace. I have concluded it is not possible to achieve these goals with the Lagrangian as written, hence the retraction.
The hypercomplex gravity and unified GEM Lagrange densities was wrong.

Gravity continues to work fine, even though we don't know why. Newton wrote down the first calculus based description. Gravity worked at a distance for reasons beyond our reach. Einstein developed a more accurate description with a little help from his friends, including Grossman, Hilbert and Schwarzschild. "Matter tells space how to warp. And warped space tells matter how to move" is John Wheeler's circular logic jerk. My own work suggests gravity is all about doing close to absolutely nothing, pushed to do trivial harmonic motions because there is other stuff in the Universe.
The sixth Snarky Puzzle Answers leads off with the story of a minor controversy.

[Click or skip this video reading on YouTube.] 
Two related Snarky Puzzles
September 20, "Deriving the Maxwell Source Equations Using Quaternions (2/5)"
RETRACTION: I have decided to retract three blogs (Deriving … 4/5, 5/5, 6/5+1). I was unable to figure out a reasonable statement concerning gauge symmetry. When the blogs were initially written, I focused on the field equations, mainly the Gauss-like law, and ignored the force equations entirely. Finding a solution that works with the the field and force equations were not looked for. A consistent proposal should do all three things (fields, forces, and solutions) with grace. I have concluded it is not possible to achieve these goals with the Lagrangian as written, hence the retraction.
RETRACTION: I have decided to retract three blogs (Deriving … 4/5, 5/5, 6/5+1). I was unable to figure out a reasonable statement concerning gauge symmetry. When the blogs were initially written, I focused on the field equations, mainly the Gauss-like law, and ignored the force equations entirely. Finding a solution that works with the the field and force equations were not looked for. A consistent proposal should do all three things (fields, forces, and solutions) with grace. I have concluded it is not possible to achieve these goals with the Lagrangian as written, hence the retraction.
Nature abhors a magnetic monopole, although she adores gravitational and electric monopoles. The homogeneous Maxwell equations are the ones that need no currents, known as the no magnetic monopoles and Faraday's laws. There are three ways to derive the homogeneous Maxwell equations. The first way is to use vector identities. This is the simplest approach, the one most widely used. Pick out a particular way to write the electric and magnetic field, and the job is done. The divergence of a curl is a long way to say zero. Define the magnetic field as a curl, then its divergence is zero, and there are no magnetic monopoles hiding behind the couch.