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Galactic Survey: The Universe Dying as Old Stars Fade Faster Than New Ones Are Born
astroengine writes: A study of more than 200,000 galaxies, encompassing wavelengths of light from the far ultraviolet to infrared, shows that the universe is producing half as much energy as it did 2 billion years ago and continues to fade. "Newer galaxies are simply putting out less energy than galaxies did in the past," astronomer Mehmet Alpaslan, with NASA's Ames Research Center in Mountain View, Calif., told Discovery News. In other words, astronomers, for the first time, have gathered observational evidence that our universe is slowly marching toward its eventual heat death (in a few trillion years time).
"Heat," in an atomic sense, is basically a measurement of how constrained molecules are within a structure and how rapidly they're bouncing around. "Cold" molecules are those that arelocked into a rigid structure and don't move around much. "Hot" molecules are ones that move about freely, without constraint. In that sense, the "heat death" of the universe will be when there is no more solid matter in the universe, and all of its atoms are distributed evenly, bouncing around freely.
Karma: Terrifying (mostly affected by atrocities you've committed)
Speaking of Disney, isn't copyright the one thing that can outlast the heat death of the universe?
Time dilation isn't proven, otherwise we wouldn't have been able to see anything.
What are you babbling about? The GPS system has detailed time dilation compensation built into it. It's not only proven, it has to be accounted for in the engineering of a functioning system in worldwide use.
GPS satellites are moving at 14,000 km/hr relative to Earth's surface, a Special Relativity time dilation of 7 microseconds per day. But Earth-based clocks are deeper in the gravity well of Earth, so they suffer a General Relativity time dilation of 45 microseconds per day. The nanosecond accurate clocks on board the satellites are pre-calibrated before launch to tick more slowly than they should while on Earth, so once in orbit, they tick at a General-Relativity-time-dilation-compensated rate that then matches Earth clocks. The software still has to compensate for any additional, unpredictable drift caused by orbital variances.
Time dilation is quite real, and must be accounted for, or GPS and Galileo wouldn't work at all. Uncompensated clock error amounts to 10km on Earth per day.