Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Alan McDougall on 16/01/2009 23:05:37
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hi
Re: Nature of Time
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At the event horizon of a black hole time almost stops.
Because an object with more massive than earth, time will flow slower , relative to earth
Ina singularity of almost infinite gravity time will stop
This poses a problem to me, it time stops at the singularity that created our universe, time must stop so how was the universe created if here were no time?
Alan
It is believed by many there was no time and flow of was created a that moment
But how ?
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I think any answer to that question has to be just a guess. Nobody can know that. My guess is that there was no Big Bang. The red shift is simply age effects on photons.
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I have just had as idea. I remember Alan Guth and his theory expansion and I like it ( not sure how to spell Guth )
Guth propose that something caused the universe to expand stopped and emerged into what is now our universe, the singularity was infinitely massive with a gravity billions of time than a black hole
The emerging expanding universe became this massive with less gravity, so time began flow at first at a snails pace, but as it got bigger, and less massive with less gravity time must have flowed faster and faster If our universe dies a cold death time will speed up to infinity and have no meaning
Who or what pushed the universe out letting entropy and time to flow?
Alan
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I was just reading a cosmology book called "Nothingness" where the author mentioned a Hawking conjecture that before some point in the course of the big bang, space and time might have looked "the same" just as EM and the weak force are united at certain energies and, it is supposed, the other forces as well. At some point there is a so-called spontaneous breaking of symmetry that leads to differentiation of time and space. I don't necessarily understand that, but there it is.
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Vern
I think any answer to that question has to be just a guess. Nobody can know that. My guess is that there was no Big Bang. The red shift is simply age effects on photons.
If the universe infinite and eternal. like you proposed this would solve the difficulty around, time, mass , matter, gravity and everything else
An infinite universe would not have the difficulties relating to time
An infinite universe would/is will have intrinsic mass and gravity binding all that is and time would be localised, mainly as a measurement of how we move in relation to everything else.
Alan
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We are very much used to looking at and thinking of time on our own scale of about a tenth of a second to a century. Beyond that we cannot really appreciate time.
The interaction times between atoms and nucleons are so vastly smaller so that allows plenty of time for complex things to happen. Also you have to remember that relatavistic and presumably gravitational field time dilation does not slow down the interactions between atoms it only allow unstable atoms more time to interact.
This was how relatavistic time dilation was proved in the first instance. Cosmic rays generate mu mesons in the upper atmosphere and these have a half life of about a microsecond and should decay after they have moved about a mile at around the velocity of light but because they ARE travelling at close to the velocity of light they last longer. Long enough to be observed at the earth's surface.
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It poses a problem if we define space (3D + time) as the only media for anything to exist in.
But if you have something existing as a (dimensionless) 'point' containing all energy we know of.
And that 'point' breaks down into a quark gluon soup that starts to 'congregate/inflate'.
If that 'inflation' keeps going, without time having an definite arrow, then we will have what we call space and distance.
Another thing one could do is to wonder if/how matter 'coming too' form influences space and distances.
If every speck of matter have its own 'sphere' of space as well as 'time'.
That could also be a part of an 'inflation'.
And if matter is space and also defines our arrow of time, as i believe, then that arrow will come first after 'matter' is formed.
But that beginning is an enigma:)
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Vern
I think any answer to that question has to be just a guess. Nobody can know that. My guess is that there was no Big Bang. The red shift is simply age effects on photons.
If the universe infinite and eternal. like you proposed this would solve the difficulty around, time, mass , matter, gravity and everything else
An infinite universe would not have the difficulties relating to time
An infinite universe wood/is will have intrinsic mass and gravity binding all that is and time would be localised, mainly as a measurement of how we move in relation to everything else.
Alan
Yes; that's probably why I like the idea of an infinite universe. It is less painful to think about [:)]
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The Planck length is the scale at which classical ideas about gravity and space-time cease to be valid, and quantum effects dominate. This is the ‘quantum of length’, the smallest measurement of length with any meaning.
And roughly equal to 1.6 x 10-35 m or about 10-20 times the size of a proton.
The Planck time is the time it would take a photon traveling at the speed of light to across a distance equal to the Planck length. This is the ‘quantum of time’, the smallest measurement of time that has any meaning, and is equal to 10-43 seconds. No smaller division of time has any meaning. With in the framework of the laws of physics as we understand them today, we can say only that the universe came into existence when it already had an age of 10-43 seconds.
JILA scientists detect strontium's "ticks" (430 trillion per second) by bathing the atoms in very stable red laser light at the exact frequency that prompts jumps between two electronic energy levels. The JILA team recently improved the clock by achieving much better control of the atoms. For example, they can now cancel out the atoms' internal sensitivity to external magnetic fields, which otherwise degrade clock accuracy. They also characterized more precisely the effects of confining atoms in the lattice.
One American trillion (i.e. 1012) would equal about 31,688 years 269 days 17 hours 34 minutes 25 seconds. (Leap years counted)
So approx = 32 000 times 32 = 160 000 years or one hundred and sixty thousand years
Or most accurate time measuring device using America trillion is
Correct to one second in 160 thousand years
British trillion (i.e. 1018) would equal about 31,688,738,506 years 296 days 8 hours 48 minutes 33 seconds. (Leap years counted)
Approx = 32 000 000 000 years times 23 = 160 million years
Or the most accurate time measuring devise using the British trillion is correct to one second in 32 billion years
I don’t think we ever reach a moment
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hi
Re: Nature of Time
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At the event horizon of a black hole time almost stops.
There's no need to be so vague or imprecise; at the Event Horizon, which is actually the Schwarzschild Radius of a Black Hole, the rate of time reduces to zero. It doesn't just nearly stop.
Because an object with more massive than earth, time will flow slower , relative to earth
Ina singularity of almost infinite gravity time will stop
Using almost infinite here doesn't really help yourself. The actual value isn't unknown or vague, or even nearly infinite. While gravity can be conjectured to be infinite at the singularity itself, this is way inside the Schwarzschild radius, at which the rate of time becomes zero. The gravity at the Schwarzschild radius is far from infinite and just depends upon the mass of the black hole, and as someone pointed out in another recent thread, the value for gravitational acceleration at the EH actually gets smaller as the BH gets larger.
This poses a problem to me, it time stops at the singularity that created our universe, time must stop so how was the universe created if here were no time?
Alan
It is believed by many there was no time and flow of was created a that moment
But how ?
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I think it is thinking of time as a flow that is causing you problems. Time appears to be the same, in absolute terms, as space, and just as space doesn't flow past us when we move through it, neither does time. Rather, we move through space and time. This difference isn't purely academic, or just dependent upon your point of view; any object having a non-zero rest mass will experience acceleration if it changes it's motion, whereas if it was stationary and space (and time) was just moving past it, it would feel no acceleration as it's motion changed.
Thus, time didn't stop at the initiation of the Big Bang - it was created, and our movement through it was started, with the initiation of the BB.
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The universe was not created. The question is therefore nonsensical.
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LeeE
Thus, time didn't stop at the initiation of the Big Bang - it was created, and our movement through it was started, with the initiation of the BB.
I agree
I think it is thinking of time as a flow that is causing you problems. Time appears to be the same, in absolute terms, as space, and just as space doesn't flow past us when we move through it, neither does time. Rather, we move through space and time. This difference isn't purely academic, or just dependent upon your point of view; any object having a non-zero rest mass will experience acceleration if it changes it's motion, whereas if it was stationary and space (and time) was just moving past it, it would feel no acceleration as it's motion changed
If time does not flow then it must move in ever tiny jerks or stop starts ,through the fabric of space
There's no need to be so vague or imprecise; at the Event Horizon, which is actually the Schwarzschild Radius of a Black Hole, the rate of time reduces to zero. It doesn't just nearly stop.
You are right of course, infinity is a naughty word in science [;D]
-tisus -------------------------------------------------------------------------------
The universe was not created. The question is therefore nonsensical.
Oh! Man you and the great alien know this and you will not explain youselves [::)] [>:(]
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The universe was not created.
Oh yes then prey tell us in one paragraph or less what did happen.
Cheers
justaskin
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There's no need to be so vague or imprecise; at the Event Horizon, which is actually the Schwarzschild Radius of a Black Hole, the rate of time reduces to zero. It doesn't just nearly stop.
LeeE I just don't get this.I saw it explained the other day that if you were watching a spaceship enter a black hole it would appear to an observer to stop
at the EH.So how long would the spaceship appear to be stopped.For all time?.If the observer looked away and looked back would the spaceship still appear to be at the EH.As the spaceship has now passed the EH and is apparently gone from all time how could you still see something.
What is it I am not getting here?.
Cheers
justaskin
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What that meant to be a play on words, you saying 'prey'?
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No but good wasn't it. [;D]
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[::)] [::)] [::)] [;D] [;D]
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justaskin
LeeE I just don't get this.I saw it explained the other day that if you were watching a spaceship enter a black hole it would appear to an observer to stop
at the EH.So how long would the spaceship appear to be stopped.For all time?.If the observer looked away and looked back would the spaceship still appear to be at the EH.As the spaceship has now passed the EH and is apparently gone from all time how could you still see something.
What is it I am not getting here?.
It would appear to stop and hang there forever. But in the infinity of time it must dissipate its energy due to relentless entropy. Even a black hole is not eternal in the unimaginable distant future it will decay and vanish from what is left of the universe
I cant wait for it to happen [8D] [;)]
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There's no need to be so vague or imprecise; at the Event Horizon, which is actually the Schwarzschild Radius of a Black Hole, the rate of time reduces to zero. It doesn't just nearly stop.
LeeE I just don't get this.I saw it explained the other day that if you were watching a spaceship enter a black hole it would appear to an observer to stop
at the EH.So how long would the spaceship appear to be stopped.For all time?.If the observer looked away and looked back would the spaceship still appear to be at the EH.As the spaceship has now passed the EH and is apparently gone from all time how could you still see something.
What is it I am not getting here?.
Cheers
justaskin
It's about gravity and time.
The more gravity that surrounds you and your frame, the faster all other frames with less gravity will be to you.
And when people living on one of those other frames look at you, you will seem to age slower, move slower, etc etc, than them.
http://www.mariner.connectfree.co.uk/Gravity/Extreme_gravity/extreme_gravity.html
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I think it is thinking of time as a flow that is causing you problems. Time appears to be the same, in absolute terms, as space, and just as space doesn't flow past us when we move through it, neither does time. Rather, we move through space and time. This difference isn't purely academic, or just dependent upon your point of view; any object having a non-zero rest mass will experience acceleration if it changes it's motion, whereas if it was stationary and space (and time) was just moving past it, it would feel no acceleration as it's motion changed
If time does not flow then it must move in ever tiny jerks or stop starts ,through the fabric of space
You're getting the bit that moves wrong; it's you that is moving, not time.
Whether your movement through it is smoothly continuous or in a series of discrete jumps is a different issue.
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There's no need to be so vague or imprecise; at the Event Horizon, which is actually the Schwarzschild Radius of a Black Hole, the rate of time reduces to zero. It doesn't just nearly stop.
LeeE I just don't get this.I saw it explained the other day that if you were watching a spaceship enter a black hole it would appear to an observer to stop
at the EH.So how long would the spaceship appear to be stopped.For all time?.If the observer looked away and looked back would the spaceship still appear to be at the EH.As the spaceship has now passed the EH and is apparently gone from all time how could you still see something.
What is it I am not getting here?.
Cheers
justaskin
You, as a distant observer, wouldn't see it still hanging there.
As you watched it, the light from it, by which you see it, would become dimmer and dimmer, and eventually it's energy content would drop to zero.
Let's say that the spaceship is shining a light towards you at a frequency of about 750 THz (violet light). As the rate of time decreases for the spaceship it will appear to take longer for each cycle of the light to be emitted; when the rate of time for the spaceship has dropped to a factor of 0.5 it will appear to take two seconds for the spaceship to emit the same 750 terracycles of light, effectively reducing it's frequency to 375 THz, and thus below the visible spectrum. As the rate of time for the spaceship gets lower and lower, the frequency of the light continues dropping until you reach the point where both the rate of time and the frequency of the light reduces to zero, meaning that there's zero energy in it.
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LeeE
You're getting the bit that moves wrong; it's you that is moving, not time.
Whether your movement through it is smoothly continuous or in a series of discrete jumps is a different issue.
That's what I believe, time is just a human construct to measure movement
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So, do you 'move' when in a coma?
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Of course you move, breath in and out in and out heart pumps and pumps
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So, do you 'move' when in a coma?
Of course you do. You're moving through space, as the Earth spins on it's axis, and as the Earth orbits the Sun, and as the Solar System rotates around the center of the Galaxy, and as the Galaxy moves towards Andromeda, and the local group moves within the Virgo super-cluster. And then you're also moving through time.
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Sorry.
'Move in time' that should mean.
If 'time' is a function of our minds?
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The universe was not created.
Oh yes then prey tell us in one paragraph or less what did happen.
Cheers
justaskin
Universes are like black holes without gravity. So long as no information is exported to the Void, the inside is irrelevant. So nothing happens; each just does its own thing internally, sound and fury signifying nothing.
At least one religion came up with a infinite (at unlimited) string of creators, something like "turtles all the way down." The same people seem to have invented zero, so perhaps the game was productive.
Others just assume a miracle.
Anyway, it's really a different topic.
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LeeE, you wrote "The gravity at the Schwarzschild radius is far from infinite and just depends upon the mass of the black hole"
If that is correct, and it seems to me to be, then one can wonder what kind 'infinite mass' we are talking about inside that black hole.
As there seems to be smaller and greater event horizons:)
Greater and smaller 'infinite masses' then?
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Where do these infinite masses come from? The mass of a star, pre-collapse is finite; why should it become infinite post-collapse?