Observing with Street Lights

Observing with Street Lights
Dark sky sites not always necessary to see the Milky Way (This image was taken ouside of a B&B in Julian, CA)

Sunday, May 29, 2016

Offsite in Amsterdam, Reading Sean Carroll's The Big Picture and a video by Lisa Randall's proposed connection between dark matter and dinosaurs

Greetings from Palmia Observatory (currently at Okura Hotel in Amsterdam)

Well our fantastic vacation along the Rhine River from Basel to Amsterdam, in this mostly cloudy region, is coming to an end and all we saw in the sky was Jupiter and a few stars and the moon poking through the clouds.  Oh well there was a lot to see on the ground.  I also had some free time to read email and get started on reading Caltech's Sean Carroll's book, "The Big Picture", so I can offer a few comments in lieu of an Astro photo.

First, Searching for Gravity Waves, Dr Gary, commented on my recent photo of a large sundial mounted on the side of a church.  He told an interesting anecdote about
his childhood experience of building a sundial and actually making measurements and splitting the daylight into halves.  Thanks Gary.  All of us amateurs have probably had some similar experience with sun dials in our childhood?  Or maybe even as adults?

Secondly, Science Geek and Theatre Impresario, Scott, forwarded a reference for a lecture by Lisa Randall commenting on her recent book about Dark Matter and the Dinosaurs.  Thanks Scott.  Those of us at the APS meeting in Salt Lake City heard her make a similar presentation.  At first you might not think of a connection between dark matter and dinosaurs, but Lisa attempts to make a case of a connection.  If you want check out the lecture that Scott found at:

Thirdly, I've been digging into "The Big Picture" and have been really enjoying the book.  Now, I have Sean's major gravity textbook, "Spacetime and Geometry" and I continue to struggle through it as part of my ongoing effort to get an understanding of Einstein's general relativity.  That has taken me a lot of effort, but his latest book is more easy reading and if you have any interest in how modern physics can comment on the rest of reality around us, then you might want to get the book.

The attached photo is an image from Sean's book and to me it really summarizes the current state of physics.  Note how everything, all energy and forces and matter, we deal with in everyday experience is described by the current status of physics called the "Core Theory".  There are still unknowns, such as dark matter and dark energy, discovered by astrophysics, that still do not have an explanation by the core theory.  This explanation will require new physics.

Now, the most surprising thing that Sean says about this is there can't be new physics discovered about the everyday world.  This is really surprising when the nature 95% of the universe is still not known.  Sean's argument, is that the core theory is so well tested and evaluated at 10-12 decimal places of accuracy, and the everyday world is so much constrained by what is already known, that no new forces or particles will be discovered.  His argument is based on quantum field theory and how everything we deal with in our everyday world is described by QFT as low energy and long wavelength fields and that whatever the explanation for dark energy and dark matter is that it will have to be described by high energy and short wavelength fields.  Sean is careful about his statement and tells of the many physicists in the past who made predictions about the future and whose predicts turned out to be wildly wrong.  But Sean says the case now is that physics is so well tested and its constraints so well established that his conclusion is correct, no matter what the final theory that includes explanations and predictions for dark matter and dark energy turns out to be.

Wow, that is pretty neat.  I like the idea and it seems to make sense, but I still have a little skepticism about such predictions, but the constraints imposed by current physics seem to go along with the prediction.  I'm only about half way through the book so stay tuned.

See you all next week from our local observatory location,

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