Wednesday, October 20, 2010

WMAP Goes to Sleep

Certainly near the top of the list of scientific instruments that have changed mankind’s view of the cosmos is NASA’s Wilkinson Microwave Anisotropy Probe (WMAP). In September 2010, the spacecraft fired its boosters for the last time and curved into a final orbit around the Sun where it will remain as a permanent fixture in the universe it helped to interpret.

WMAP was launched on June 2001 to revolutionize the field of cosmology. WMAP studied the remnants of heat that lingered after the Big Bang, a pattern frozen in time from when the universe was only about 380,000 years old. The light arriving to WMAP from this great distance has since stretched to microwave wavelengths. Subtle differences observed in the texture of this so-called “cosmic microwave background” have revealed the geometry, composition and age of the universe. The probe showed that the universe is flat, and most likely endless. It also yielded the first full-sky map of the cosmic microwave background (see inset image). Other results included how this primeval light is polarized and forms the blueprint for the first galaxy formation.

During its illustrious mission, WMAP science has been extremely fertile. Its findings produced some of the most highly cited papers in physics. And although WMAP science has come to a conclusion, its replacement is already in orbit: the European Space Agency’s Planck satellite.

WMAP’s discoveries have resonated far beyond the scientific sphere. Singer-songwriter Katie Melua’s 2005 hit “Nine Million Bicycles” included the lyrics:
“We are 12 billion light years from the edge
That’s a guess
No one can ever say it’s true.”
When science journalist Simon Singh pointed out that  the lyrics did not reflect current scientific knowledge (WMAP determined the age of the universe with great accuracy), Melua agreed to re-record the song:
“We are 13.7 billion light years from the edge of the observable universe

That’s a good estimate with well-defined error bars
And with available information”
Listen to the before and after version here. Now that is one scientifically responsible artist!

 

Sunday, October 10, 2010

AMS Einstein Lecture

It was a warm Indian summer evening on the UCLA campus last Saturday night (October 9), and the feeling surrounding Schoenberg Hall was electric with anticipation for the “Einstein Lecture” by Fields Medalist Professor Terence Tao of UCLA. I arrived early to absorb the ambiance, and I wasn’t disappointed – it was fascinating to see such widespread interest in mathematics.

The weekend saw mathematicians from far-off locations converge on the Math Sciences building for the regional meeting of the American Mathematical Society (AMS). The free public lecture that was scheduled for the evening hours not only attracted the mathematicians on-hand from the conference, but also people from many other walks of life, including seniors and children.

As I sat reading a recent arXiv paper on modified gravity and gravitational waves, I surveyed the venue. There was a large area where serving tables were set up, alongside several large round tables designated for enjoying the food and drinks at the reception after the lecture. Not surprisingly, many of the attendees arrived early because the seating was first-come-first-served. A department insider told me that 1,000 people RSVP’d, but the lecture hall only seats 500. The organizers reserved a second hall for 200 more guests, and anyone else would have to watch the lecture on a large projection unit set up outside on the patio. As I sat soaking in the color, I noticed the guest of honor – Professor Tao, arrive dressed in a formal black suit. This was making out to be quite an affair – imagine that, mathematics on a Saturday night!

The name of the lecture was “The Cosmic Distance Ladder.” Even though Professor Tao is a world renowned expert in research mathematics, his talk for the evening was concerning astrophysics. Rarely overviewed all at once, Tao led us through man’s journey in determining his place in the university. How do we know the distances from the earth to the sun and moon, from the sun to the other planets, and from the sun to other stars and distant galaxies? Clearly we can’t measure them directly. Nevertheless there are many ingenious indirect methods of measurement, combined with basic mathematics, which can give quite convincing and accurate results without the need for advanced technology. Even the Greeks could compute the distances from the earth to the sun and moon to moderate accuracy. Tao’s talk focused on these methods that rely on climbing a “cosmic distance ladder,” using measurements of nearby distances to deduce estimates on distances slightly farther away. In the lecture, he discussed the current 9 “rungs” of this ladder.

It was a fascinating lecture and a superb way to spend a Saturday night. I attended the lecture with two old friends from my undergrad days at the UCLA Mathematics Department. At the wonderfully catered reception that followed I had the opportunity to catch up with the past iteration of department chairman, Professor Christoph Thiele, and current chair Professor Sorin Popa. It was a night to remember for sure, under the stars and with the distinct scent of world-class mathematics in the air.


Wednesday, October 6, 2010

Back to School

The Physics Groupie is taking a small step forward in his formal astrophysics education (one of the reason for fewer posts here on the SLB). I am officially auditing a very cool class at UCLA this Fall 2010 quarter – Astronomy 4 “Black Holes and Cosmic Catastrophes.” The class is taught by Professor Alice Shapley, a rising star of the UCLA astrophysics department who was literally stolen away from Princeton in 2008. I’ve met Alice a number of times before and knew I’d enjoy any class she taught. I have not been disappointed, the class is wonderful, a tribute to her engaging teaching style. With her dry-pan sense of humor, she could be a pretty damn good comedian.

The class is square in my area of interest – black holes, but it is much more than that. Shapley is going through some Newtonian dynamics, Keplerian orbits, spectroscopy, and my favorite – gravity. Although an undergrad course for non-majors, it serves me as a springboard for the future. After a life in computer science, many of you know I switched focus about 5 years ago in favor of astrophysics. I had to start somewhere, so this class is a great place. A goal of mine is to ease back into student mode, and after years in industry it isn’t all that simple. Eventually, I’d like to enter a Masters Degree program in astrophysics or astronomy, and time permitting, a Ph.D. program. But I’m getting way ahead of myself.

The class is already providing an excellent framework for revisiting a lot of elementary physics that I haven’t had since I was an undergrad. It is interesting how the hyper-competitive undergrad environment at UCLA looks at this review material. I asked one fellow student (probably only 18 or 19 years old) about the physics being taught in the class. The reply I got was, “Oh, I had all this in high school.” Ah, the precocious youth of today.

Again, this is a course for non-majors, but I’m taking it more seriously than most. Instead of the textbook recommended for the class, I’m using the renowned Halliday & Resnick which is much more intense and mathematical. This textbook is on its 8th edition and originally written by venerable RPI emeritus professor Robert Resnick. I’m also reviewing MIT physics (aka Course 8) material for 8.01 and 8.02 through MIT OpenCourseware to supplement the material being covered in my class.

I’m looking forward to the meat of the class in the weeks to come, namely black holes. With my past experience with the LIGO project and gravitational wave astronomy, plus my more recent interest in the Galactic center with our Milky Way’s supermassive black hole, I’m anticipating a very good learning experience indeed.

[I’d appreciate any comments about returning to the academic world after a long absence. Is this doable?]

Friday, October 1, 2010

SLB – Winner of Design and Lifestyle Award

Theaterseatstore.com
Awards 2010
I am pleased to report that the Science Lifestyle Blog received a “Best on the Net” award for combined design and lifestyle content. The Design and Lifestyle 2010 Web Excellency Awards selected websites in a variety of genres but the SLB was the only award winning site in the area of math and science. The selection process was described this way:

“ … after many hours of searching and reviewing, we’ve come across what we feel to be the best combined design and lifestyle blogs on the net. All of the subsequent winners in this category are both incredibly well designed and feature a strong narrative voice with a knack for creating truly engaging content. Anyone who visits them is sure to take away some form of inspiration …”
I realize that a blog devoted to covering topics in mathematics and science typically will not be on the top of most people’s list, so I’m even happier that we were chosen. Viva la science!