It got me thinking about relativity and time passing slower for those closer to the black hole than those far away. I somewhat understand relativity, but from my understanding, it's a relative thing and the people on earth are aging...**** it. You know what I mean.

But is there any "evidence" to say that bodies actually age at different rates? I mean on a biological level. For example the classic case is the space man on a ladder extending from a ship towards a black hole. He perceives the person in the ship as aging while he stays the same.

But isn't that just perception? They are in the same space and relative time shouldn't make their bodies age any faster.

Or does light from stars prove this to be "true"? That is, we see light from stars that have long since burned out. Or maybe not. Isn't the idea that they are burned out just an extension of the same theory? Do we have evidence that the stars are in fact burned out?

We've measured (and regularly correct for) clocks on satellites running at a tiny bit different speeds. So in short it's real, enough to correct for so our GPS isn't off but they effect is way to small for a meaningful age difference to develop.

I couldn't find any experiments that demonstrate that a biological organism does age at different rates at higher speeds / higher gravity. But, it all seems that it would be in line with the implications of the theory. Actual experimentation to demonstrate this phenomenon would be difficult - the ISS, for example, travels at 17,500km/h which is like 0.01% the speed of light. I've read about experiments that have studied bacterial growth on the ISS vs on Earth, but putting bacteria on a space station and flying it around the Earth introduces many other variables and doesn't isolate for affects of relative velocity. And even if it could, we're still talking about a relatively small difference in relative velocity. If we could build a rocket to go half the speed of light, zoom around the galaxy for a few years and come back, we could demonstrate the principle at the scale you are asking about.

For a more physical example of time dilation, there are observations and experiments with sub-atomic particles (which we can get to significant fractions of the speed of light) that seem to uphold the theories. I won't pretend to be anywhere close to qualified to explain those, but there are papers out there.

You can play around with it, since it's all just numbers.

https://www.calctool.org/relativity/time-dilation

nortex97 said:

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You can play around with it, since it's all just numbers.

https://www.calctool.org/relativity/time-dilation

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Thats awesome!

I put in 6.5km/s for the ISS speed and then started playing with the time. If I did it right, 10,000,000,000 years on the ISS would work out to 10,000,000,0002 years on Earth.

Aggrad08 said:

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We've measured (and regularly correct for) clocks on satellites running at a tiny bit different speeds. So in short it's real, enough to correct for so our GPS isn't off but they effect is way to small for a meaningful age difference to develop.

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What's amazing is we pre-programmed the clocks on GPS satellites that orbit farther from earth to account for time dilation, so that by the time the data from the satellites reach earth, the time is precisely in line with the time on earth.

Amazing how Einstein figured this out over 100 years ago. What boggles my mind about time dilation is it is not biological or anything. It just is. Objects and organisms moving faster will have their clocks move slower. So a person will age slower and clocks will literally tick slower relative to someone on earth. And this is proven true by the GPS satellites.

Mind boggling stuff. Hopefully one day we can do an experiment on a scale to the level of scifi movies, e.g. someone aging a few days in the span of decades on earth.

I "understand" more or less why relativistic travel causes time dilation. I took advanced physics in high school, and I'm pretty good with advanced math. But I can't wrap my head around gravity wells causing time dilation. Can someone ELI5?

I've wondered how this might tie into a "6 day creation". If the universe expanded over billions of years is it possible from the vantage point of the densest gravitational spot at the beginning that it only took a couple days? Or the speed at which matter expanded outward created this time bending effect? From our vantage point here on earth we can say it's X billions of years but maybe from the perspective of moving faster than light, it's a couple weeks old.

Obviously we say God is outside of time and nothing in the OP was religious in nature but it's always been a fun concept to ruminate on. Please don't take this as an attempt at apologetics. I also did not take advanced physics and am working with a base level knowledge of what this theory is to begin with

I think the issue is 'what is a day to God?' Pretty sure I am not smart enough/divinely inspired to give the answer (codker I think has it all worked out mathematically).

I'm just glad to watch the sun rise in the East daily, God-willing, and patience isn't even close to my strength.

The faster I work, the faster I age, so my empirical evidence says this time dilation thing is backwards.

It's my understanding that they've experimentally confirmed time dilation. Decay rates of particles accelerated to near light speeds change exactly as predicted, for example. I used to know a physicist that worked for a satellite company. Part of his job was to develop the corrections necessary to adjust the clocks on the satellites with clocks on earth. The satellite clocks would change relative to earth clocks due to time dilation, despite the fact that the satellites were only traveling at a tiny fraction of C.

I understand the point but absolutely cannot get my head around "why". Einsteinian physics as well as quantum mechanics are not something we are aware of in our everyday experiences so they make little common sense to us.

What has always fascinated me with this is, velocity in respect to what, exactly. I mean, we are always moving. Earth rotating on its axis. Earth around the Sun. Sun around the galaxy.

So, theoretically, if we could be on a plant that just stayed put and the Galaxy revolved around it, how would that effects things.

And...why? What is about out fundamental basics that are so completely change by velocity through space?

Wonderfully interesting topic.

The Green Dragon said:

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It got me thinking about relativity and time passing slower for those closer to the black hole than those far away. I somewhat understand relativity, but from my understanding, it's a relative thing and the people on earth are aging...**** it. You know what I mean.

But is there any "evidence" to say that bodies actually age at different rates? I mean on a biological level. For example the classic case is the space man on a ladder extending from a ship towards a black hole. He perceives the person in the ship as aging while he stays the same.

But isn't that just perception? They are in the same space and relative time shouldn't make their bodies age any faster.

Or does light from stars prove this to be "true"? That is, we see light from stars that have long since burned out. Or maybe not. Isn't the idea that they are burned out just an extension of the same theory? Do we have evidence that the stars are in fact burned out?

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