Shape of the universe

Citation

(2001), "Shape of the universe", Sensor Review, Vol. 21 No. 3. https://doi.org/10.1108/sr.2001.08721cab.007

Shape of the universe

Shape of the universeKeywords: Temperature, Sensors

What is the shape of the universe? Scientists at JPL may have an answer to the cosmological question, thanks to precise temperature measurements from a small micromesh bolometer. Using advanced MEMS techniques, the group was able to build the Web-shaped sensor with only 1 percent of the material required for conventional bolometers. The device's supporting structure is just 1 micron thick, the same thickness as a strand in a spider's web or about 100 times finer than a human hair. The result of this gossamer design is a sensor with extremely high sensitivity.

JPL's bolometer can measure temperature ±0.0001°C, sensitive enough to detect from Earth the heat given off by a coffee maker located on the Moon. The sensors affixed to a high altitude (23 miles above Antarctica) balloon mapped temperature variations in the cosmic background radiation. The observed density patterns, say researchers, are consistent with an inflationary theory that says the universe went through an exponential inflation moments after the Big Bang. The theory further predicts a "flat" geometry for the universe because the immense stretching of space during such an inflation would have removed any initially strong curvature in the smaller and denser early universe. If we were to balance a large ball, we would feel the curvature beneath our feet. But, expanding that ball to a cosmic scale flattens the visible universe.

The bolometer was a key part of the international sponsored balloon observations of millimetric extragalactic radiat and geophysics (Boomerang) programme. Bolometers from JPL are several times more sensitive than current models, and are expected to fly on the European Space Agency's Infrared and Submillimeter Telescope (First) and Planck missions, both scheduled for launch in 2007.