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Author Topic: Can we relate time dilation to escape velocity?  (Read 11500 times)

Offline jeffreyH

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Re: Can we relate time dilation to escape velocity?
« Reply #25 on: 12/03/2015 23:00:04 »
Strangely John there is a Mr John Duffield and a Mr Stuart J Duffield at SPIE. Which one are you? Doesn't this get confusing over who wrote what. One may easily think one Duffiled wrote something when in fact it was the other. That would be unfortunate.
« Last Edit: 12/03/2015 23:02:24 by jeffreyH »
 

Offline jeffreyH

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Re: Can we relate time dilation to escape velocity?
« Reply #26 on: 12/03/2015 23:18:45 »
John you aren't going to claim to be an authority on spinors are you? How much group theory do you know? This is an honest question and I think it deserves an honest answer. If you are going to be making these claims and representing yourself as an authority, where people might actually be convinced that they are learning established physics from you, then put up or shut up. It is hard enough to learn physics without being waylaid by bogus claims. You do every enthusiastic amateur an injustice by doling out spurious information simply to boost your status in the eyes of others.
 

Offline jeffreyH

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Re: Can we relate time dilation to escape velocity?
« Reply #27 on: 12/03/2015 23:45:21 »
Last night I watch the Horizon programme on the BBC about the search for the gravitational waves from the big bang. Alan Guth was one of the physicists included. He propose the theory of inflation right at the start of his career. Finding those waves will tell us a lot more about the big bang and validate Alan's theory. The guys set up telescopes at the pole and spent 3 years recording CMBR from a dark spot in the sky. Then after 3 years they found the data wasn't accurate enough. They then went away and built a better telescope and spent several more years looking for the b mode signal of the early gravitational waves. They found something that looked like the signal and spent more time analyzing it and ruling things out until they were confident in announcing it. Then it was shown that at least 50% of it and maybe 100% of the signal was due to dust. That is physics.
 

Offline jeffreyH

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Re: Can we relate time dilation to escape velocity?
« Reply #28 on: 12/03/2015 23:48:51 »
For anyone interested in the signal there is information here;

http://background.uchicago.edu/~whu/intermediate/Polarization/polar6.html
 

Offline jeffreyH

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Re: Can we relate time dilation to escape velocity?
« Reply #29 on: 13/03/2015 00:16:00 »
The thing that crosses my mind about the equation

g = c^2/(2[rs+n]*SQRT(1-rs/[rs+n]))

is how would this relate to the Bekenstein bound

http://en.wikipedia.org/wiki/Bekenstein_bound

and the chandrasekhar limit

http://en.wikipedia.org/wiki/Chandrasekhar_limit

If a connection to the black hole entropy can be found that would be a positive step. With the chandrasekhar limit it may be possible to put a lower and upper bound on possible black hole masses. In respect of the big bang this could be very important if the idea of a singularity is to hold.
 

Offline JohnDuffield

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Re: Can we relate time dilation to escape velocity?
« Reply #30 on: 13/03/2015 01:01:02 »
Jeffrey: David Simmons-Duffin was being overly hostile. Take a look at the picture on the quora page. Then note that the Dirac spinor is a bispinor, and have a look at Dirac's belt on Mathspages:

"In contrast, the Mobius strip is a non-orientable surface, because a right-handed figure, moved continuously around the loop until arrive back at its starting point, becomes left-handed. An object must be translated around the loop twice in order to be restored to its original position and chirality. In this sense a Mobius strip is reminiscent of spin-1/2 particles in quantum mechanics, since such particles must be rotated through two complete rotations in order to be restored to their original state...

I'm John Duffield. I don't know any Stuart J Duffield. I'm not claiming to be an authority on spinors or group theory, I'm just telling you about things that aren't in the popscience/student books/articles/etc you've been reading. Do not think that something is "spurious information" or isn't "established physics" just because you don't know about it. The vast bulk of what I tell you about is established physics. I didn't invent the word spinor, and I didn't write the Wikipedia article or put this picture on it:



Quote
Last night I watch the Horizon programme on the BBC about the search for the gravitational waves from the big bang. Alan Guth was one of the physicists included. He propose the theory of inflation right at the start of his career. Finding those waves will tell us a lot more about the big bang and validate Alan's theory. The guys set up telescopes at the pole and spent 3 years recording CMBR from a dark spot in the sky. Then after 3 years they found the data wasn't accurate enough. They then went away and built a better telescope and spent several more years looking for the b mode signal of the early gravitational waves. They found something that looked like the signal and spent more time analyzing it and ruling things out until they were confident in announcing it. Then it was shown that at least 50% of it and maybe 100% of the signal was due to dust. That is physics.
The Horizon producers pulled their punches, and didn't say anything about the orchestrated hype that put people's back up. See Physicist Paul Steinhardt Slams Inflation, Cosmic Theory He Helped Conceive. And note this: that "first light" dates from 300,000 years after the big bang. How can that tell you anything about the first nanosecond after the big bang? The universe was a seething maelstrom of plasma for a third of a million years. It would be like putting those sonic standing waves into a blender.
« Last Edit: 13/03/2015 01:02:49 by JohnDuffield »
 

Offline jeffreyH

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Re: Can we relate time dilation to escape velocity?
« Reply #31 on: 13/03/2015 01:18:29 »
John, how do you validate anything if you don't understand it? You now say you are not an authority on spinors. What exactly DO you know about them?

Bispinor on wikipedia.

http://en.wikipedia.org/wiki/Bispinor

Have you even looked at the equations in there? You have group mapping, transformations and the SO(3;1) group all mentioned.

You can find information on orthogonal groups here:

http://en.wikipedia.org/wiki/Orthogonal_group

Try reading it.

"Equivalently, it is the group of nn orthogonal matrices, where the group operation is given by matrix multiplication, and an orthogonal matrix is a real matrix whose inverse equals its transpose."

"The determinant of an orthogonal matrix being either 1 or −1, an important subgroup of O(n) is the special orthogonal group, denoted SO(n), of the orthogonal matrices of determinant 1. This group is also called the rotation group, because, in dimensions 2 and 3, its elements are the usual rotations around a point (in dimension 2) or a line (in dimension 3). In low dimension, these groups have been widely studied, see SO(2), SO(3) and SO(4)."

What about symmetries? Does that ring any bells?
 

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Re: Can we relate time dilation to escape velocity?
« Reply #32 on: 13/03/2015 01:22:30 »
Now then John what type of matrix has its inverse equaling its transpose?
 

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Re: Can we relate time dilation to escape velocity?
« Reply #33 on: 13/03/2015 20:13:04 »
Jeffrey: David Simmons-Duffin was being overly hostile. Take a look at the picture on the quora page. Then note that the Dirac spinor is a bispinor, and have a look at Dirac's belt on Mathspages:

"In contrast, the Mobius strip is a non-orientable surface, because a right-handed figure, moved continuously around the loop until arrive back at its starting point, becomes left-handed. An object must be translated around the loop twice in order to be restored to its original position and chirality. In this sense a Mobius strip is reminiscent of spin-1/2 particles in quantum mechanics, since such particles must be rotated through two complete rotations in order to be restored to their original state...

I'm John Duffield. I don't know any Stuart J Duffield. I'm not claiming to be an authority on spinors or group theory, I'm just telling you about things that aren't in the popscience/student books/articles/etc you've been reading. Do not think that something is "spurious information" or isn't "established physics" just because you don't know about it. The vast bulk of what I tell you about is established physics. I didn't invent the word spinor, and I didn't write the Wikipedia article or put this picture on it:



Quote
Last night I watch the Horizon programme on the BBC about the search for the gravitational waves from the big bang. Alan Guth was one of the physicists included. He propose the theory of inflation right at the start of his career. Finding those waves will tell us a lot more about the big bang and validate Alan's theory. The guys set up telescopes at the pole and spent 3 years recording CMBR from a dark spot in the sky. Then after 3 years they found the data wasn't accurate enough. They then went away and built a better telescope and spent several more years looking for the b mode signal of the early gravitational waves. They found something that looked like the signal and spent more time analyzing it and ruling things out until they were confident in announcing it. Then it was shown that at least 50% of it and maybe 100% of the signal was due to dust. That is physics.
The Horizon producers pulled their punches, and didn't say anything about the orchestrated hype that put people's back up. See Physicist Paul Steinhardt Slams Inflation, Cosmic Theory He Helped Conceive. And note this: that "first light" dates from 300,000 years after the big bang. How can that tell you anything about the first nanosecond after the big bang? The universe was a seething maelstrom of plasma for a third of a million years. It would be like putting those sonic standing waves into a blender.

That article correctly states that Paul Steinhardt helped refine the theory years after Alan Guth conceived it. Don't put your own slant on things and try to rewrite history. So what if he objects to it. HE has a right to. Someone may well come up with a better theory. That is what physics is all about.
 

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Re: Can we relate time dilation to escape velocity?
« Reply #34 on: 13/03/2015 20:46:40 »
If we take the mass of the chandrasekhar limit and then calculate its Schwarzschild radius an equation can be formed thus:

g = c^2/[2rs+L/262993404a7f720f18beb5a525f009d5d.gif]

The value for g that we then get is 299788351 which just about equals the speed of light. To find the lower limit of a feasible black hole we need to vary the parameters until this acceleration is as near to the surface of the event horizon as it is possible to get. This may or may not equal 1 Planck length.

CORRECTION: c/2 has been modified to L/2 to represent the distance traveled by light in one 1/2 second. You just can't add a velocity to a distance.
« Last Edit: 13/03/2015 21:30:18 by jeffreyH »
 

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Re: Can we relate time dilation to escape velocity?
« Reply #35 on: 15/03/2015 20:01:26 »
If the limit on the lowest mass of a black hole coincides with the acceleration at one Planck length from the horizon being equal to the speed of light then that would relate directly to black hole entropy and the Bekenstein bound.
 

Offline SorryDnoodle

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Re: Can we relate time dilation to escape velocity?
« Reply #36 on: 15/03/2015 20:36:32 »
Quote from: Ethos
We are all familiar with the escape velocity of a black hole as being equal to c.

If that were the case, wouldn't light escape?
Yes of course...........I should have said "escape velocity greater than c." But greater by only the smallest degree.

Would't escape velocity be proportional to the mass of the black hole, in other words; A very small black hole being very close to c but a super massive black hole very much great than c?

If not, why?
 

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Re: Can we relate time dilation to escape velocity?
« Reply #37 on: 15/03/2015 21:04:31 »
Quote from: Ethos
We are all familiar with the escape velocity of a black hole as being equal to c.

If that were the case, wouldn't light escape?
Yes of course...........I should have said "escape velocity greater than c." But greater by only the smallest degree.

Would't escape velocity be proportional to the mass of the black hole, in other words; A very small black hole being very close to c but a super massive black hole very much great than c?

If not, why?

A black hole traps light at its event horizon. That is why it is called an event horizon because we cannot retrieve any information beyond the horizon. As the radius of the event horizon increases so does the mass but the density of the gravitational field decreases proportionally. If the escape velocity at the event horizon exceeded c then it would no longer be the event horizon. In that case the event horizon would be larger in radius.

You can find details here.

http://en.wikipedia.org/wiki/Schwarzschild_radius
 

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Re: Can we relate time dilation to escape velocity?
« Reply #37 on: 15/03/2015 21:04:31 »

 

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