It depends on whaqt one means by the word "understand". I do kind of understand much of what was written. Your writing was nice and clear. But, I don't really have a clear picture of a gravitational wave or of spacetime. My last physics course was in 1964. And, it didn't cover up to date discoveries as of that date.
I did put some basic explanations in the beginning of my article, but my editor cut them. I guess they assume certain knowledge and want to get quickly to the news.
This probably won't help, but...spacetime is all the space around us, plus time. So every point in spacetime has four numbers associated with it: one designating the time there, and three designating its position in space, for example, how far up/down a point is, how far left/right it is, and how far forward/back it is.
Are you familiar with sound waves, as oscillations in the air? There, half a sound wave consists of air that's been compressed a bit, and the other half is where it's been relaxed (anti-compressed, if you will)?
Gravitational waves are similar, but instead of air being compressed it's spacetime that's being compressed. But the compressions are VERY TINY -- only about 10^-21 compared to uncompressed spacetime.
They also cut out some my basic stuff on neutron stars, but here's something, from Wikipedia, that is amazing:
"If an object were to fall from a height of one meter on a neutron star 12 kilometers in radius, it would reach the ground at around 1400 kilometers per second."
Congratulations, David. Wish I understood it.
ReplyDeleteThanks.... But I was hoping any diligent reader could understand it. No?
ReplyDeleteIt depends on whaqt one means by the word "understand". I do kind of understand much of what was written. Your writing was nice and clear. But, I don't really have a clear picture of a gravitational wave or of spacetime. My last physics course was in 1964. And, it didn't cover up to date discoveries as of that date.
ReplyDeleteThanks for the clarification.
ReplyDeleteI did put some basic explanations in the beginning of my article, but my editor cut them. I guess they assume certain knowledge and want to get quickly to the news.
This probably won't help, but...spacetime is all the space around us, plus time. So every point in spacetime has four numbers associated with it: one designating the time there, and three designating its position in space, for example, how far up/down a point is, how far left/right it is, and how far forward/back it is.
Are you familiar with sound waves, as oscillations in the air? There, half a sound wave consists of air that's been compressed a bit, and the other half is where it's been relaxed (anti-compressed, if you will)?
Gravitational waves are similar, but instead of air being compressed it's spacetime that's being compressed. But the compressions are VERY TINY -- only about 10^-21 compared to uncompressed spacetime.
They also cut out some my basic stuff on neutron stars, but here's something, from Wikipedia, that is amazing:
ReplyDelete"If an object were to fall from a height of one meter on a neutron star 12 kilometers in radius, it would reach the ground at around 1400 kilometers per second."
https://en.wikipedia.org/wiki/Neutron_star#Gravity_and_equation_of_state