Time and speed and how speed impacts time

[swansont]

31 minutes ago, interested said:

But wouldnt spaghettification of your ruler inside a black hole cause the distance to be shorter to the centre of the BH

Nobody said anything about a ruler, and spaghettification has no effect on distance, just on physical objects. Breaking a ruler does not change the distance between two points.

[Strange]

39 minutes ago, interested said:

Light is blue shifted and red shifted depending on if the source is moving away from you or towards, if it is blue shifted its frequency appears higher, and it has more energy, gravity waves travel at light speed, if a planet is moving towards you, is the gravitational intensity greater ie does gravity experience a form of blue shift and red shift.

Gravity is not carried by waves, so there is no frequency shift involved.

[koti]

1 hour ago, interested said:

Light is blue shifted and red shifted depending on if the source is moving away from you or towards, if it is blue shifted its frequency appears higher, and it has more energy, gravity waves travel at light speed, if a planet is moving towards you, is the gravitational intensity greater ie does gravity experience a form of blue shift and red shift. Could this effect the strength and or focus of gravity orbiting a planet.

Edit

Are you meaning lensing or distance to the bottom of a trough, or gravity well if you observe a circle on 2 D space PI D applies. Nothing weird about it.

However if the length of your ruler changes over a stretched surface then yes I get what you are saying, the ruler gets longer towards the middle of the circle in a gravity well, or stretched space.

Edit 

But wouldnt spaghettification of your ruler inside a black hole cause the distance to be shorter to the centre of the BH

PI can have a different value in extreme curvature like in the case of a black hole.

[interested]

2 hours ago, Strange said:

Gravity is not carried by waves, so there is no frequency shift involved.

Ligo gravity waves.

[Strange]

13 minutes ago, interested said:

Ligo gravity waves.

Gravity does not depend on gravitational waves. There are no gravitational waves from the Earth but we still have gravity.

But, yes, gravitational waves would be red-shifted by relative motion of the source and receiver as well as by cosmological red-shift. But this does not affect the strength of gravity from an object.

[geordief]

15 minutes ago, Strange said:

Gravity does not depend on gravitational waves. There are no gravitational waves from the Earth but we still have gravity.

But, yes, gravitational waves would be red-shifted by relative motion of the source and receiver as well as by cosmological red-shift. But this does not affect the strength of gravity from an object.

But gravity waves are an integral part of the gravity effect,aren't they? .The gravity field we currently experience was perhaps "built up" from the earliest period we have knowledge of  by tiny increments of changes due gravity waves (which themselves could not come into existence without a pre-existent  local(?)gravity  field..

[Strange]

17 minutes ago, geordief said:

But gravity waves are an integral part of the gravity effect,aren't they? .

No. "Normal" gravity is static(*). Gravitational waves are only created in specific situations, requiring a type of asymmetry, such as two massive objects orbiting one another. There are no gravitational waves involved in the gravity of the Earth or any other body.

(*) OK. The Moon orbiting the Earth or the Earth orbiting the Sun will create minute gravitational waves. They are pretty much irrelevant to anything, though, because they are so all (and slow). 

[geordief]

2 minutes ago, Strange said:

No. "Normal" gravity is static(*). Gravitational waves are only created in specific situations, requiring a type of asymmetry, such as two massive objects orbiting one another. There are no gravitational waves involved in the gravity of the Earth or any other body.

(*) OK. The Moon orbiting the Earth or the Earth orbiting the Sun will create minute gravitational waves. They are pretty much irrelevant to anything, though, because they are so all (and slow). 

 Because they (presumably ) can't be measured does that mean they don't exist?

 

Would quantum effects come into play when the conditions were  small enough?

[Strange]

6 minutes ago, geordief said:

Because they (presumably ) can't be measured does that mean they don't exist?

I suppose they could be measured, in principle. The frequency is too low for LIGO (which has a lower frequency of about 1 Hz, I think). I don't know how to calculate the magnitude of the waves, but obviously, because we are right here, they might be detectable.

8 minutes ago, geordief said:

Would quantum effects come into play when the conditions were  small enough?

At some point, yes, I assume. (If gravity is quantised.) I have no idea at what level that would happen, though.

[Janus]

1 hour ago, geordief said:

 Because they (presumably ) can't be measured does that mean they don't exist?

 

Would quantum effects come into play when the conditions were  small enough?

The gravitational waves produced by the Earth orbiting the Sun amounts to 200 watts,  but have a period of 1 year and thus a wavelength of 1 light year.

Gravitational waves are produced by an accelerating mass in much the same way as electromagnetic waves are produced by an accelerating electric charge.

An non-accelerating electron has an electromagnetic field, but produces no electromagnetic waves. Take that electron and start it vibrating and it will begin to emit electromagnetic waves of a frequency equal to its vibration. The energy of the waves will come from the motion of the electron, and if left to itself the vibration will die out.

A non-accelerating mass has a gravitational field, but produces no gravitational waves.  To make it produce gravitational waves, you would have to accelerate it.  The Earth orbiting the Sun is a type of acceleration that produces gravitational waves, and it does so at the cost of orbital energy (The Earth slowly moving closer to the Sun). 

The LIGO detected gravitational waves came from two massive black holes giving up orbital energy as they merged. Their large masses and the very short period of their orbits just before the merger generated intense gravity waves of short wavelengths which where detected by LIGO.

The gravitational field and gravitational wave are related, but distinct things.

[Country Boy]

On ‎1‎/‎20‎/‎2018 at 6:14 AM, koti said:

PI can have a different value in extreme curvature like in the case of a black hole.

"pi" is a number and does not change value.  I presume what you mean is that in curved space (it doesn't have to be "extreme") the Euclidean relation between circumference and diameter of a circle does not hold so "pi" is irrelevant.

Edited January 25, 2018 by Country Boy

[druS]

On 1/21/2018 at 1:51 AM, Strange said:

Gravity does not depend on gravitational waves. There are no gravitational waves from the Earth but we still have gravity.

But, yes, gravitational waves would be red-shifted by relative motion of the source and receiver as well as by cosmological red-shift. But this does not affect the strength of gravity from an object.

Thanks Strange. As an interested novice (interested observer lol) this was an "AHA!" moment for me.