2019

On August 7th, News started a discussion on time’s arrow (which ties to the second law of thermodynamics). I found an interesting comment by FF: FF, 4: >> It’s always frustrating to read articles on time’s arrow or time travel. In one camp, we have the Star Trek physics fanatics who believe in time travel in any direction. In the other camp, we have those who believe only in travel toward the future. But both camps are wrong. It is logically impossible for time to change at all, in any direction. We are always in the present, a continually changing present. This is easy to prove. Changing time is self-referential. Changing time (time travel) would require a velocity in time Read More ›

On this date in 1944 one of the first computers, the IBM Mark I, became operational.  See the Wiki article here.  From the article: [The Mark I] could do 3 additions or subtractions in a second.  A multiplication took 6 seconds, a division took 15.3 seconds, and a logarithm or a trigonometric function took over one minute. Now, here is the question for the class.  What is the difference, in principle, between the Mark I and the IBM Summit, which, as of late 2018, became the fastest supercomputer in the world, capable of performing calculations at the rate of 148.6 petaflops (one petaflop is one thousand million million floating-point operations per second)? The answer, of course, is “absolutely nothing.”  Both Read More ›