How exactly does gravity affect time?

[Brian37]

The whole idea of time being relative is really hard for me to grasp. Even when I see the theory and the maths laid out, part of my brain still shouts, "Yeah, but bollocks!"

I've tried thinking more of time as a fourth dimension rather than a simple parameter. That has helped a bit.

I'm wondering if time is defined in terms of the rate of change of distance with respect to speed; rather than the more usual formulation. Does that make any sense.... or help?

You cant separate space and time, in science it is called space/time.  Think of space/time as a fabric, like a bed sheet, put a bowling ball in the middle of it, it will dent the bed sheet.

You are fighting your flawed perceptions because your perception is local and limited. Quantum math allows us to understand the larger picture. It is really counter intuitive for most because we live in the macro world and we are not used to thinking about the bigger picture on a daily basis.

[ErGingerbreadMandude]

Clocks ticking faster in places with lesser gravity just shows that movement is lesser restricted,right? Does it really imply time moves faster? Is there some other kind of evidence like a particle aging at different rates in places with different gravity?

[Brian37]

Clocks ticking faster in places with lesser gravity just shows that movement is lesser restricted,right? Does it really imply time moves faster? Is there some other kind of evidence like a particle aging at different rates in places with different gravity?

This isn't hard to understand. Don't think of time like the clock on your wall, that is local and relative to you. Think of it like a dent in something. Just like a roulette wheel, the sun being the center, heavier and bigger, causes the white ball to fall around it. A black hole is even a heaver center and the gravity is so great not even light can escape it.

Trust me the math proves space time is a fabric and gravity does affect time. It is why GPS satellites have to be adjusted in orbit. It is just that our layperson's brains for most, simply don't think about the math on a daily basis. This really cuts to your false perceptions. Humans simply are simply not born with that math in their heads at birth. So we grow up with very local perceptions.

[robvalue]

Indeed, my brain cannot properly handle it yet. It is stuck in monkey mode.

[Brian37]

Indeed, my brain cannot properly handle it yet. It is stuck in monkey mode.

I can't do a fraction to save my life, but I do know scientific method works, if it didn't we wouldn't be having this exchange on products produced through scientific method.

Just have the attitude that your local perception outside of math is flawed. Math in science is really how we know what is going on. It really is no different than knowing that that butterfly in the ink blot is not a real butterfly. 

Science is why pilots are trained to avoid false perceptions when flying in clouds and low visibility, they have to be trained to know that their body and brains can be fooled without proper training. 

Even if you cant do the math, with the right overall explanation you can gain a layperson's view. Just like you don't need to be able to build every car part from scratch to know how to drive a car and understand the idea of a combustion engine. It certainly is a plus if you can get that deep in math, but for most, you still can have a basic understanding.

[robvalue]

Sure

Ironically I can do maths no problem generally. It's visualizing the reality, in cases of complex physics, that I struggle with. If I had the time and energy to study it more, I'm sure I'd get a better view. For now I just trust the theory is right, and I don't trust my intuition. I stick with the maths.

I love maths! I used to be a maths teacher.

[Brian37]

Sure

Ironically I can do maths no problem generally. It's visualizing the reality, in cases of complex physics, that I struggle with. If I had the time and energy to study it more, I'm sure I'd get a better view. For now I just trust the theory is right, and I don't trust my intuition. I stick with the maths.

I love maths! I used to be a maths teacher.

Knowing the math helps. I think about my X wife and here microbiology PHD degree, and the poet brain I got stuck with. I still would not give up my brain as a trade, but if  could have both, damn sure would love it. Just to be Hawking for one day. I think though, long term, the more people who get the best education they can have and the less indoctrinated the world is, the more problem solving our species can have.

[Alex K]

Since we're on a tangent, here's another silly one for you Alex.
Whatever Dark energy/Dark Matter is, it's always been there. C is a constant.
Would the value of true theoretical value of C change if we discovered it was being restricted by this Dark Matter/Energy.
EG: Is there such a thing as a true void in space?

I would say it is the other way around - if you give up the assumption of a constant speed of light, relativity theory needs such a profound revision that the meaning of dark energy and its properties might need to be rethought completely. As far as we understand now, dark energy does not affect the speed of light in this sense, nor does dark matter. The only effect DM should have on light is that it slows time through its gravity, and so as seen from far away light appears to take longer from A to B.