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 »

I enjoyed Johannes Koelman's blog, "Velocity: Stuff That Doesn't Add Up."  If you haven't read it, please consider doing so. I will review just the math here. There was a technical point that probably flew over many a reader's head. When discussing the elegance of the Lorentz relativity approach, he mentions a hyperbolic tangent.  Hyperbolic trig functions used to cause me hypertension. With a little math and a few pictures, gone is my fear. Hopefully the reader will feel these strangers are not so strange after reading this blog.

Galileo Velocity Roundup
Jan. 23, Slit Experiments and Coherence Patterns
Snarky Puzzle
The coherent source is often modeled as a plane wave. Write the quaternion valued plane wave like so:

A0 is the amplitude
omega is an angular frequency
k is a wave vector
[Title correction: My goal was to create images of 2D, 3D, and 4D functionals. I think I missed that target. Instead I have 1D parameterized curves that all move in up to 3D in space + time. I have a clear idea how to write new code that could move independently with two, three, or four parameters. That code is not written now, so I will change the title to more accurately reflect the content.]

Nothing like writing a title where I am not sure if I can pull it off. It reminds me of skiing slowly off a 6 foot cliff in Colorado. By the time I landed, I was going fast. Nothing like the constant acceleration of gravity.

One, Two, Three D

Sophisticated physicists appreciate the dance of abstract symbols. I need to build something. The abstract is more real when made out of clay and pipe cleaners. In this blog on the 1D Euler Lagrange equations, beads (not clay) and pipe cleaners will be used to appreciate this important tool, followed by the same story told with symbols.

[note: I missed my usual self-imposed deadline because I was not able to get the icon bar to appear in Google Chrome on a Mac. The browser Opera worked, so long as I cut and plasted URLs for images and HTML code from codecogs.]
The  6 minute YouTube video, available in high def, provides a walking tour of my private Pop Science art collection. One painting spent a summer month in Lancaster, PA as part of a juried show. "Turquoise Einstein" was a hit with the public, but did not win "Best in Show" because it was too happy. Happy art is not serious art.

Most of these piece were created around 1995. Each piece was driven by equations I was pondering about in physics. The math is right, wrong or I don't understand it, but at least it looks good.
I spent the week seeing if I could give the good old college try and find a "way that worked" for the gauge games I have been playing. Nothing panned out. Bummer, I had a blog to write. While collecting crumpled paper, there was an old issue I wasn't able to figure out. The answer was probably known a hundred years ago. The blog will explain where I got stuck, and who knows, maybe someone will provide the answer.