What does knowledge about black holes do for us on Earth?
How can we use that information practically?
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QuixoticSoul · 41-45, M
General relativity, which first indicated that there would be such phenomena, is used in your GPS.
Also, pure research of any kind often leads to spin-off technologies, etc - and often has unpredictable interdisciplinary results. And funding rarely goes to waste - this black hole photo thing leaves us with eight better telescopes to do more science with. These things compound.
And it's pretty cheap in the grand scheme of things.
Also, pure research of any kind often leads to spin-off technologies, etc - and often has unpredictable interdisciplinary results. And funding rarely goes to waste - this black hole photo thing leaves us with eight better telescopes to do more science with. These things compound.
And it's pretty cheap in the grand scheme of things.
Tastyfrzz · 61-69, M
@QuixoticSoul I think the Doppler shift concepts used in gps are still non- relativistic. Our laser interferometer calculations didn't require it.
QuixoticSoul · 41-45, M
@Tastyfrzz It’s an issue of synchronization across frames of reference.
[quote]Because an observer on the ground sees the satellites in motion relative to them, Special Relativity predicts that we should see their clocks ticking more slowly (see the Special Relativity lecture). Special Relativity predicts that the on-board atomic clocks on the satellites should fall behind clocks on the ground by about 7 microseconds per day because of the slower ticking rate due to the time dilation effect of their relative motion [2].
Further, the satellites are in orbits high above the Earth, where the curvature of spacetime due to the Earth's mass is less than it is at the Earth's surface. A prediction of General Relativity is that clocks closer to a massive object will seem to tick more slowly than those located further away (see the Black Holes lecture). As such, when viewed from the surface of the Earth, the clocks on the satellites appear to be ticking faster than identical clocks on the ground. A calculation using General Relativity predicts that the clocks in each GPS satellite should get ahead of ground-based clocks by 45 microseconds per day.
The combination of these two relativitic effects means that the clocks on-board each satellite should tick faster than identical clocks on the ground by about 38 microseconds per day (45-7=38)! This sounds small, but the high-precision required of the GPS system requires nanosecond accuracy, and 38 microseconds is 38,000 nanoseconds. If these effects were not properly taken into account, a navigational fix based on the GPS constellation would be false after only 2 minutes, and errors in global positions would continue to accumulate at a rate of about 10 kilometers each day! The whole system would be utterly worthless for navigation in a very short time.
The engineers who designed the GPS system included these relativistic effects when they designed and deployed the system. For example, to counteract the General Relativistic effect once on orbit, the onboard clocks were designed to "tick" at a slower frequency than ground reference clocks, so that once they were in their proper orbit stations their clocks would appear to tick at about the correct rate as compared to the reference atomic clocks at the GPS ground stations. Further, each GPS receiver has built into it a microcomputer that, in addition to performing the calculation of position using 3D trilateration, will also compute any additional special relativistic timing calculations required [3], using data provided by the satellites.[/quote]
[quote]Because an observer on the ground sees the satellites in motion relative to them, Special Relativity predicts that we should see their clocks ticking more slowly (see the Special Relativity lecture). Special Relativity predicts that the on-board atomic clocks on the satellites should fall behind clocks on the ground by about 7 microseconds per day because of the slower ticking rate due to the time dilation effect of their relative motion [2].
Further, the satellites are in orbits high above the Earth, where the curvature of spacetime due to the Earth's mass is less than it is at the Earth's surface. A prediction of General Relativity is that clocks closer to a massive object will seem to tick more slowly than those located further away (see the Black Holes lecture). As such, when viewed from the surface of the Earth, the clocks on the satellites appear to be ticking faster than identical clocks on the ground. A calculation using General Relativity predicts that the clocks in each GPS satellite should get ahead of ground-based clocks by 45 microseconds per day.
The combination of these two relativitic effects means that the clocks on-board each satellite should tick faster than identical clocks on the ground by about 38 microseconds per day (45-7=38)! This sounds small, but the high-precision required of the GPS system requires nanosecond accuracy, and 38 microseconds is 38,000 nanoseconds. If these effects were not properly taken into account, a navigational fix based on the GPS constellation would be false after only 2 minutes, and errors in global positions would continue to accumulate at a rate of about 10 kilometers each day! The whole system would be utterly worthless for navigation in a very short time.
The engineers who designed the GPS system included these relativistic effects when they designed and deployed the system. For example, to counteract the General Relativistic effect once on orbit, the onboard clocks were designed to "tick" at a slower frequency than ground reference clocks, so that once they were in their proper orbit stations their clocks would appear to tick at about the correct rate as compared to the reference atomic clocks at the GPS ground stations. Further, each GPS receiver has built into it a microcomputer that, in addition to performing the calculation of position using 3D trilateration, will also compute any additional special relativistic timing calculations required [3], using data provided by the satellites.[/quote]
Tastyfrzz · 61-69, M
Probably why my Garmin now has my saved locations all five miles off from where I set them.
CopperCicada · M
There is two sides of this.
One question is what value does the methodology used in this discovery have. The study used a network of telescopes and thus big data, and special algorithms looking at and correlating small signals.
Who knows. Such methods could be applied to any number of wide array imaging studies from medicine to environmental studies to defense and security.
People often say WTF. Putting people on the moon. The moon aside all of our medical telemetry comes from what was dev'd out in the space program.
You never know how tools and technologies transfer. I have used in my own work image processing algorithms that were inspired by genetics and animal herd behavior. And that is processing images of materials.
The other thing is that this array and algorithm was used to look into deep space at black holes. Surely the next thing will be to turn it to a whole other set of astrophysical problems.
Who knows where that goes. Maybe something massive like discovering life in the universe. Maybe this method of looking at the shadow created around bodies can be used to probe those bodies in some fadhion. Maybe these algorithms can be used to look at things in our solar system using different arrays. Who the fuck knows.
As for the black hole itself-- the general theory of relativity is well tested. But a direct image is something that's never existed. The best we have is gravitational lensing, seeing objects behind a massive object so to speak.
But a direct image of a black hole has a lot more information, and I can see that used for deeper tests of the general theory of relativity. And that becomes a bigger deeper test of fundamental physics.
So it's far from a pfft. Who cares thing.
One question is what value does the methodology used in this discovery have. The study used a network of telescopes and thus big data, and special algorithms looking at and correlating small signals.
Who knows. Such methods could be applied to any number of wide array imaging studies from medicine to environmental studies to defense and security.
People often say WTF. Putting people on the moon. The moon aside all of our medical telemetry comes from what was dev'd out in the space program.
You never know how tools and technologies transfer. I have used in my own work image processing algorithms that were inspired by genetics and animal herd behavior. And that is processing images of materials.
The other thing is that this array and algorithm was used to look into deep space at black holes. Surely the next thing will be to turn it to a whole other set of astrophysical problems.
Who knows where that goes. Maybe something massive like discovering life in the universe. Maybe this method of looking at the shadow created around bodies can be used to probe those bodies in some fadhion. Maybe these algorithms can be used to look at things in our solar system using different arrays. Who the fuck knows.
As for the black hole itself-- the general theory of relativity is well tested. But a direct image is something that's never existed. The best we have is gravitational lensing, seeing objects behind a massive object so to speak.
But a direct image of a black hole has a lot more information, and I can see that used for deeper tests of the general theory of relativity. And that becomes a bigger deeper test of fundamental physics.
So it's far from a pfft. Who cares thing.
SumKindaMunster · 51-55, M
@CopperCicada Excellent response, thank you for your thoroughness.
Dainbramadge · 56-60, M
SumKindaMunster · 51-55, M
ItsGonnaBeOk · 26-30, M
@SumKindaMunster there were footages of stars orbiting around the black hole, isn't that enough?
SumKindaMunster · 51-55, M
@ItsGonnaBeOk I can't say, can you? I think knowledge is always helpful, we can build from it. The more you know....
BlueMetalChick · 26-30, F
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BlueMetalChick · 26-30, F
@Tastyfrzz Gravitational reactions release a lot more of their potential energy than chemical or nuclear reactions. Because gravity is the weakest of the four fundamental forces of physics has nothing to do with its potential in creating a power source for us, especially since we'll never run out of gravity.
Tastyfrzz · 61-69, M
@BlueMetalChick yes, in the form of dams but Newtonian physics is adequate for that. Don't get me wrong, I'm all for cool physics and knowledge but I think there also needs to be some cost justification. Kids can't afford to go to school just to learn how to read.
BlueMetalChick · 26-30, F
@Tastyfrzz So perhaps a better thing to reallocate money from might be the eight hundred billion dollars we spend every year bombing foreign countries, or the two hundred billion we spend buying illegal weapons for Muslim terrorists to commit genocide with, or the one hundred and fifty billion we spend bailing out banks and giving welfare checks to wealthy corporations. Perhaps we should stop giving tax exemptions to churches. Those are better ways to find money to improve school systems and increase wages, not cutting into the science budget, especially considering how relatively small it is already. Publicly financed science programs are dying out thanks to privatized shitheels like Elon Musk.
AngelofFail · 26-30, F
Tastyfrzz · 61-69, M
@AngelofFail Newtonian physics works just fine for that at non-relativistic speeds.
mindstruggle · M
MartinTheFirst · 22-25, M
It further proves the theory of relativity
Tastyfrzz · 61-69, M
@MartinTheFirst ok, and then what?
MartinTheFirst · 22-25, M
@Tastyfrzz nothing for now
