The Naked Scientists

The Naked Scientists Forum

Author Topic: What is a singularity?  (Read 6041 times)

Offline petrovitch

  • Jr. Member
  • **
  • Posts: 19
    • View Profile
What is a singularity?
« on: 09/11/2008 12:54:01 »
We all assume that the point of singularity was in a steady state.  It could not travel because there was no place to go; the universe did not exist. As things approach the speed of light they get shorter and shorter until they reach the speed of light in which case their length is zero.

What if the point of singularity was traveling at the speed of light and inflation is the result of transition into sub-light speed.  The universe expands at a faster and faster rate.  As the matter created from this transition from energy to matter slows down it would get longer and longer.  Could this explain the value of k being greater than zero?

If the point of singularity was spinning instead of being in a stead state that would explain how spiral galaxies spin, and maybe even solar systems.  Pre-matter particles thrown off would have memory of creation (mathematical affects of spin; not biological memory from neurons).
« Last Edit: 09/11/2008 22:35:30 by chris »


 

Offline DoctorBeaver

  • Naked Science Forum GOD!
  • *******
  • Posts: 12656
  • Thanked: 3 times
  • A stitch in time would have confused Einstein.
    • View Profile
Re: What is a singularity?
« Reply #1 on: 09/11/2008 12:57:35 »
Quote
It could not travel because there was no place to go; the universe did not exist.

Quote
What if the point of singularity was traveling at the speed of light

Can you not see a slight contradiction there?
 

Offline syhprum

  • Neilep Level Member
  • ******
  • Posts: 3810
  • Thanked: 19 times
    • View Profile
Re: What is a singularity?
« Reply #2 on: 09/11/2008 13:28:27 »
I see another contradiction, spinning! relative to what?
 

Offline petrovitch

  • Jr. Member
  • **
  • Posts: 19
    • View Profile
Re: What is a singularity?
« Reply #3 on: 09/11/2008 17:17:45 »
Of course I see the contradictions, but that's assuming time and space did not exist before the big bang.  What if?
 

Offline LeeE

  • Neilep Level Member
  • ******
  • Posts: 3382
    • View Profile
    • Spatial
Re: What is a singularity?
« Reply #4 on: 09/11/2008 18:28:54 »
Without time you can only have a steady/stable state because you need time for the state to change.  With just space, you can have many states, in different locations, but they'll all exist simultaneously, with no causality, and they'll all be steady/stable.

Having said that, if the ordering/causality is abstract to the states then you could still say that there is a sequence.  For example, draw seven 'Scrabble' tiles from a bag at random and lay them out in front of you in the order that they were drawn.  The chances are that you will not draw the letters in alphabetical order and they will therefore not be laid out in front of you in alphabetical order.  However, the fact that they are not laid out in alphabetical order doesn't change the order of the alphabet.  Now stack the tiles on top of each other, in a single pile, and in the reverse order to which you drew them out of the bag - this still doesn't change the order of the alphabet.  So, where the order of the alphabet is the important thing, the order in which you draw the tiles, or even the way you arrange them, is irrelevant.
 

lyner

  • Guest
Re: What is a singularity?
« Reply #5 on: 09/11/2008 21:07:23 »
Quote
Without time you can only have a steady/stable state because you need time for the state to change.
Here's another example of someone treating time as a necessarily different class of dimension.
I don't think there need be such an essential difference.  A graph of x against y can be the same shape as a graph of x against t.
Differentiable and continuous functions can occur between any two variables. (At least in pure Maths)
Even the requirement, in our experience, that t can only increase, could be merely a local constraint.
(Some of) the extra dimensions which are invoked in String Theory  could also follow the 'monotonic' rule which time follows here/now.
 

Offline stevewillie

  • Sr. Member
  • ****
  • Posts: 120
    • View Profile
Re: What is a singularity?
« Reply #6 on: 09/11/2008 21:51:38 »
Quote
Without time you can only have a steady/stable state because you need time for the state to change.
Here's another example of someone treating time as a necessarily different class of dimension.
I don't think there need be such an essential difference.  A graph of x against y can be the same shape as a graph of x against t.
Differentiable and continuous functions can occur between any two variables. (At least in pure Maths)
Even the requirement, in our experience, that t can only increase, could be merely a local constraint.
(Some of) the extra dimensions which are invoked in String Theory  could also follow the 'monotonic' rule which time follows here/now.

Sophiecentaur

By basing the arrow of time on experience, you're suggesting causality "violations" may be possible. I happen to agree with you. I've suggested in other posts that causality is an operational concept based on the idea of a necessary and sufficient condition. It's an empirical concept, not a mathematical or logical one. Nevertheless, you're treading on dangerous ground when you allow causality violations at macroscopic scales.   
« Last Edit: 13/11/2008 21:56:43 by stevewillie »
 

Offline DoctorBeaver

  • Naked Science Forum GOD!
  • *******
  • Posts: 12656
  • Thanked: 3 times
  • A stitch in time would have confused Einstein.
    • View Profile
What is a singularity?
« Reply #7 on: 09/11/2008 22:55:38 »
Can someone explain monotonicity in idiot language, please  ???
 

Offline LeeE

  • Neilep Level Member
  • ******
  • Posts: 3382
    • View Profile
    • Spatial
What is a singularity?
« Reply #8 on: 10/11/2008 03:18:40 »
Quote
Without time you can only have a steady/stable state because you need time for the state to change.
Here's another example of someone treating time as a necessarily different class of dimension.
I don't think there need be such an essential difference.  A graph of x against y can be the same shape as a graph of x against t.
Differentiable and continuous functions can occur between any two variables. (At least in pure Maths)
Even the requirement, in our experience, that t can only increase, could be merely a local constraint.
(Some of) the extra dimensions which are invoked in String Theory  could also follow the 'monotonic' rule which time follows here/now.

Did you only read the first sentence of the first paragraph?
 

lyner

  • Guest
What is a singularity?
« Reply #9 on: 10/11/2008 09:39:45 »
Can someone explain monotonicity in idiot language, please  ???
Sorry - "only goes one way". Increases or decreases.


LeeE
I have to admit that I didn't quite get what you were saying. Have another go; SHOUT if necessary.
« Last Edit: 10/11/2008 09:43:13 by sophiecentaur »
 

lyner

  • Guest
What is a singularity?
« Reply #10 on: 10/11/2008 09:53:30 »
stevewillie
Quote
causality is an operational concept based on the idea of a necessary and sufficient condition. It's an empirical concept, not a mathematical or logical one.

I'd go along with that, not having thought it through totally (but has anyone?).

Being empirical implies that we could 'go somewhere else (whatever that might mean)' and find things to be different.

Or we could say the Mathematics is just a superset which includes our reality.
 

Offline DoctorBeaver

  • Naked Science Forum GOD!
  • *******
  • Posts: 12656
  • Thanked: 3 times
  • A stitch in time would have confused Einstein.
    • View Profile
What is a singularity?
« Reply #11 on: 10/11/2008 11:46:29 »
Can someone explain monotonicity in idiot language, please  ???
Sorry - "only goes one way". Increases or decreases.

I thought that was it. Thank you. I'm a musician and monotonic means something totally different in musical terms - on 1 note.

So is the suggestion that there could be spatial dimensions that only allow movement in 1 direction?

OK, I know I keep mentioning this - entropy. Doesn't that require an "arrow of time"?
« Last Edit: 10/11/2008 11:49:20 by DoctorBeaver »
 

Offline LeeE

  • Neilep Level Member
  • ******
  • Posts: 3382
    • View Profile
    • Spatial
What is a singularity?
« Reply #12 on: 10/11/2008 14:49:11 »
Sophie:  Actually, I don't think we were disagreeing and I too think that the issue may arise from our perception of time.

Hmm... after spending a lot of time trying to word it more clearly, the best I've been able to do is come up with the waffle below, which may not even be relevant.  :-\

We appear to be moving along the time axis, from our local point of view, at a constant rate and this could be regarded as equivalent to us moving along a fourth spatial dimension in a similar manner to the way that massless particles always move at 'c' through our three spatial dimensions.  The apparent difference to us, between the spatial and temporal dimensions, is that we don't appear to be able to move freely through the temporal dimension while we can through the spatial ones.  However, if our motion through the temporal dimension is similar to the movement of massless particles through spatial dimensions then we'd have similar constraints - unless they are absorbed or reflected by something, photons have no option but to move in a straight line (through their locally perceived space-time, which may be curved), and at a constant speed.  They can't suddenly change speed or reverse direction.

I think that the perception issue arises because we only appear to occupy either a zero-sized point, or perhaps a non-zero sized quantum point, on the time axis and we can't directly experience anything outside the region that we occupy.  Funnily enough though, we can't really directly experience anything that is spatially remote from us either.  When we look at something remote, say a range of snow-capped mountains on the horizon, we don't experience the snow and when we're indoors looking out at the rain we don't get wet.  In this respect what we see is little different to a memory or prediction.

The important difference is that we can go to the mountains to directly experience the snow, or even just outdoors, to get wet, so perhaps the question shouldn't be 'why can't we move freely through time, as we can through space? but 'why can we move freely through space?

Re the causality and entropy issues: I think this is only a problem when you try to move in two directions along the time axis simultaneously - if you were to go back in time you wouldn't remember the future unless your local time-frame continued moving forwards at the same time.  If your local time-frame rolls back too, you'll un-remember things as they un-happen.
 

lyner

  • Guest
What is a singularity?
« Reply #13 on: 10/11/2008 15:10:59 »
Dr B
I'm only thinking in terms of the way the Maths doesn't exclude things.
Yes - entropy.
If we think of the increase of entropy as time increases as a given, that implies that, as time increases, entropy increases. A graph would have a positive slope. Plotted in reverse, it would mean a negative slope.
The thing about graphs involving time is that we only see one value of x for any value of t. Unlike xy graphs which can have loops.

Quote
So is the suggestion that there could be spatial dimensions that only allow movement in 1 direction?
Well, why not? And they could also, possibly, not have negative values either.

LeeE
Our 'existence in time' must be far from a point. We are 2m in height, which represents a spread of 6ns around our 'centre'. This is because 'we' are all of our body. Even if you say 'we' are in our brain, the timewidth is a bit under 1ns. Where 'is'  our consciousness?
I agree that there may be a quantum size which is associated with time but, in the same way that energy quanta vary in value, time quantum values could also depend on something else.

And - re your moving back in time comment: would you also have to retrace your steps  in every respect, i.e. would all your atoms have to move and behave generally in precisely the inverse way?
Are we just talking bollocks here?
 

Offline DoctorBeaver

  • Naked Science Forum GOD!
  • *******
  • Posts: 12656
  • Thanked: 3 times
  • A stitch in time would have confused Einstein.
    • View Profile
What is a singularity?
« Reply #14 on: 10/11/2008 16:09:17 »
Quote
If we think of the increase of entropy as time increases as a given, that implies that, as time increases, entropy increases. A graph would have a positive slope. Plotted in reverse, it would mean a negative slope.
The thing about graphs involving time is that we only see one value of x for any value of t. Unlike xy graphs which can have loops.

So you think that the law of entropy may be wrong? I find that hard to accept. Drop a cup on the floor and it breaks. Suggesting that sequence could go the other way just doesn't seem right.
 

lyner

  • Guest
What is a singularity?
« Reply #15 on: 10/11/2008 21:52:08 »
No, I'm not really saying that. I'm saying that it's just a matter of which way you look at it - how you choose to plot the graph.

I am deliberately avoiding looking at it from the standpoint of an observer 'like us' because our view is obviously biased.

I must admit that I don't usually get this whacky.
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 11978
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
What is a singularity?
« Reply #16 on: 10/11/2008 22:36:45 »
petrovitch:)
 
No matter will ever reach the speed of light.
So that proposal will only be true if you use 'something else' (photons).
And if you do that you may, or you may not, be talking about the innards of a black hole.
Nobody knows how a black hole is acting inside the event horizon.

We can't go in there and get information out.
At least not information in the sense of a ordered language as far as I understand.
And definitely not in mankind's 'lifetime' as that 'information' only should be finished as the last vestiges of that black hole disappears.
And that will take some time:)

And if you are referring to the Big Bang as the singularity?
And wondering if its possible spin would make the galaxies spin too.
Maybe, but the BB had a 'moment' of hyperinflation where it expanded faster than 'c'.
Thats about where your causality_effect would 'break down' and lose its importance too.
That as it belongs to 'our universe's laws' if you see how I think.
But some Black holes do spin and drag/twist space around them.

But i think I can see your drift here.
That as matter seems to get 'smaller and smaller' into 'nothingness' as it nears 'c'.
Why couldn't it have a relation to a singularity which also is seen as something without size?

But that is an 'illusion' as far as i know. Seen from your frame relative a fast moving object (reference frame) you will see that object shrink as it gets closer to 'c' but if you could 'teleport' on/into that object you would find everything 'as usual' lengthwise.
It's not shrinking in the sense of that movie 'darling I shrunk the kids' :)
Even though we will see it like that from our reference frame.

But the non dimensional point of a black hole may very well exist.
Just as that hyper inflation seemed to have.
But what they both have in common is that they don't follow our spacetimes laws.
singularity = The quality of being one of a kind.
And that's what joins them together,that they both are defined as being 'one of a kind'.
« Last Edit: 10/11/2008 22:51:30 by yor_on »
 

Offline DoctorBeaver

  • Naked Science Forum GOD!
  • *******
  • Posts: 12656
  • Thanked: 3 times
  • A stitch in time would have confused Einstein.
    • View Profile
What is a singularity?
« Reply #17 on: 10/11/2008 23:12:58 »
Quote from: sophiecentaur
If we think of the increase of entropy as time increases as a given, that implies that, as time increases, entropy increases. A graph would have a positive slope. Plotted in reverse, it would mean a negative slope.

Maybe I read it wrong, but that quote seems as if you're implying that time could run backwards.
 

lyner

  • Guest
What is a singularity?
« Reply #18 on: 11/11/2008 13:41:39 »
No; just that the graph can be plotted either way. If you're not actually 'experiencing' the time, the relationship could be looked at in both directions.  If you look at a mountain, which is the up slope and which is the down slope?
 

Offline DoctorBeaver

  • Naked Science Forum GOD!
  • *******
  • Posts: 12656
  • Thanked: 3 times
  • A stitch in time would have confused Einstein.
    • View Profile
What is a singularity?
« Reply #19 on: 11/11/2008 13:52:11 »
OK, I understand you now.
 

Offline LeeE

  • Neilep Level Member
  • ******
  • Posts: 3382
    • View Profile
    • Spatial
What is a singularity?
« Reply #20 on: 11/11/2008 19:17:51 »
Sophie:

Quote
Our 'existence in time' must be far from a point. We are 2m in height, which represents a spread of 6ns around our 'centre'. This is because 'we' are all of our body. Even if you say 'we' are in our brain, the timewidth is a bit under 1ns. Where 'is'  our consciousness?
I agree that there may be a quantum size which is associated with time but, in the same way that energy quanta vary in value, time quantum values could also depend on something else.

What you're considering there is the time of propagation of something across a body, not the movement of the body as a whole.  If the front of the body was moving at a different speed to the back of the body then I'd say that the length of time occupied was clearly non-zero, but while the entire body moves at the same speed there's no difference between the front and back, so the 'thickness' would be zero.  We do need to take gravitational time dilation in to account though, as this would mean that the front and back, or rather the top and bottom, would be in different time rates.

Quote
And - re your moving back in time comment: would you also have to retrace your steps  in every respect, i.e. would all your atoms have to move and behave generally in precisely the inverse way?

Yes, that's the way I'd interpret it.  Using the graph analogy, if the value of x at t1 is n1 and the value of x at t2 is n2, x will always have the value of n1 at t1, and n2 at t2.  The values shouldn't change according to the order in which you look at them and looking at the graph isn't part of the graph itself.

Quote
Are we just talking bollocks here?

Quite possibly, but I wouldn't go as far as to say probably :)
 

Offline Soul Surfer

  • Neilep Level Member
  • ******
  • Posts: 3345
  • keep banging the rocks together
    • View Profile
    • ian kimber's web workspace
What is a singularity?
« Reply #21 on: 12/11/2008 10:02:12 »
To return to the original headline question and its supplementary in the main text.

Petrovich.  A singularity is a mathematical concept and as such has only restricted application in the field of physics.  It is the mathematicians way of faying that My model is not complex enough to cope with things that really happen as gravitational collapse occurs so I end up with a singularity.  The real problem is to try to understand what might happen under conditions that are so far from what we experience or observe in nature or can measure using the highest energies and densities we can create in a laboratory.

I see your supplementary questions are a personal groping towards this understanding in the same way that I have mine.

Your first two paragraphs suggest a limited knowledge and understanding of the processes and I would encourage you to read more and clarify your ideas because it is not really possible to discuss them sensibly.  when you talk about rotation in the third you are I believe on to something but looking at it as a source of rotation is to think about it the wrong way round.  Rotation comes out of the gravitational collapse of already turbulent gases and needs no explanation but as things collapse the rotation becomes more significant and this I believe shows the way to avoid the mathematical impossibility of a truly singular state in a real universe.
« Last Edit: 12/11/2008 10:04:11 by Soul Surfer »
 

The Naked Scientists Forum

What is a singularity?
« Reply #21 on: 12/11/2008 10:02:12 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums
 
Login
Login with username, password and session length