Alex McColgan
speaker
29,301 appearances
104 recordings
1 series
first heard Nov 2024
last heard 5d ago
Alex McColgan’s voice in public audio — every appearance, attributed to the second.
Trend
recordings per month · last 12 monthsRecordings per month over the last 12 months — 68 in all, peaking in Aug 2026 with 11.
Appearances
Now, let's be clear, nothing can move faster than light, in a vacuum, but in other materials such as ice, liquid water and glass, light can be outpaced.
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This isn't a violation of physics, but rather a consequence of light slowing down more than other particles within the ice.
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As the muon races beyond its photon counterparts, it generates a shockwave of blue light expanding in a cone-shaped pattern out from its path, an eerie phenomenon known as Cherenkov radiation.
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Cherenkov radiation is most commonly associated with nuclear reactors, eerily emanating through the water that surrounds their cores.
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This blue hue in nuclear cores, and strangely also down in the ice of the South Pole, can look peaceful and atmospheric, but it is in fact the quantum equivalent of the sonic boom that roars out from a supersonic jet plane flying overhead.
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In this case, the plane moves through the air, and pressure or sound waves are pushed out in all directions.
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With the jet's speed building up towards the speed of sound, the waves in front start to bunch up, forming a shock front of high pressure.
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When the plane exceeds the speed of sound, it smashes through the shock front, causing a rapid change of air pressure.
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This is the sonic boom.
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The shock front then travels out in a cone, trailing behind the aircraft, which observers will hear as a thunderous clap.
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In the case of the muon, the particle is not pushing air, but instead disturbing the electric fields of atoms in the ice with its electromagnetic charge, polarizing the water molecules.
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As the molecules depolarise back to their usual state, they release the energy that forced them into polarisation as photons of blue light travelling out in all directions.
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This is happening all along the path the muon takes through the ice.
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The travelling muon is triggering emission of electromagnetic waves from the water ice molecules which radiate out into all directions, producing a cone of emission in the direction of the muon's motion.
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If the muon was travelling slower than light in the ice, there would be no wavefront, and all the expanding light spheres would destructively interfere with each other, cancelling out to complete darkness.
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But since the muon is travelling faster than light, the shock front of constructive waves in the form of blue light is created.
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The thousands of digital optical modules of IceCube are primed to detect this signature blue light flashing through the ice.
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The miniscule differences between when one dom registers the flash and when the neighbouring doms detect it allow scientists to triangulate the neutrino and trace its path back through the ice and ultimately through the universe to its origin.
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These orb-like detectors are marvellous, intricate devices designed to detect the faintest luminal hints in the icy mass.
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Each dome is encased in a 13-inch spherical glass pressure case, which protects the electronics inside from the extreme cold and high pressure of the Antarctic ice.
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Showing 1961–1980 of 29,301 · page 99 of 1466
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