Antarctica 2013--2014 Part 7: Science with Keck Array at the South Pole

Photo of Keck Array

The main science goal of our experiment is to measure faint microwave signals to help us better understand the Big Bang. Because the signals are so faint (equivalent to temperature fluctuations of less than 0.000001 degrees), we need incredibly sensitive detectors to find them. Furthermore, there are lots of stronger signals (e.g. from our own Galaxy) we have to reject in order to see the tiny ones from the beginning of the Universe. Therefore, most of our work here comes in two parts: upgrading our telescopes and characterizing how they respond to different types of signals.

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Antarctica 2013--2014 Part 2: Logistics

One day's worth of packages

My deployment date (the day I leave the U.S. for Antarctica) is this Friday! This time I'm writing about packing, flying, shipping, and related matters. The first thing to pack (although many leave it until the end) is personal luggage, everything you'll need for a few months away from civilization. The options for buying e.g. toiletries on the Ice are very limited so you need to bring anything you can't do without. This year I'm bringing a bunch more stuff to help me sleep--that was probably the hardest thing about being at South Pole last year.

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A Physics Puzzle from the Kitchen (sort of)

Diagram of Puzzle

Two perfect conducting spheres are immersed in a fluid with electrical conductivity σ = 5 x 10-2 S/m. The spheres have radius r = 1 mm and are maintained a distance R = 1 m apart. A potential difference of V = 220 V is maintained between the two spheres. The fluid extends to infinity. Calculate the net current flowing between the spheres. (If you've been paying attention, you've noticed that this situation violates charge continuity.

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New CMB Results from BICEP1

Likelihood for Parameter r Calculated from BICEP1 B-mode Measurement

Last week we published new results from the BICEP1 Cosmic Microwave Background (CMB) polarization experiment. (Disclaimer: I'm a coauthor of the paper.) BICEP1 is the first in a series of experiments at the South Pole searching for the signal of cosmological Inflation in the CMB. BICEP1 took data in 2006--2008, but this is the first result to include all three years of data.

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Up Goer: "Inflation"

Inspired by xkcd's Up Goer Five, I attempted to explain my research using only the ten hundred most common English words. It was pretty hard.

I try to find out what caused the beginning of everything. We think we know what happened back in time until almost the beginning. We know it was very hot then and that everything was moving away from everything else very fast. We have a good idea that explains how it got that way. The idea is called "inflation."

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Detection of CMB B-mode Polarization by SPT

Last week, members of the South Pole Telescope (SPT) collaboration reported the first detection of B-mode polarization in the Cosmic Microwave Background (CMB). Scientists have been searching for B-mode polarization for over a decade because it offers an opportunity to study all the matter in the Universe and the cause of the Big Bang.

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New Results from AMS, Speculation on Dark Matter

Photo of AMS on International Space Station

Last month the Alpha Magnetic Spectrometer (AMS) team reported a new measurement of positrons in cosmic rays (journal article, less technical summary and commentary). The results imply that new, not yet understood physical processes are producing more positrons than expected at high energies.

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