Does Consciousness Create Time in a Timeless Space?

[BL4CKB0X97]

Firstly, I don't know where to put this. Sorry if it's in the wrong place.

I was thinking about being past an event horizon, and recalled that time stops in such a place and physics breaks down.

Which made me think: should I find my self alive(and conscious)in a timeless area, surely that fact that I am there introduce a timeline? From human perspective, even if you were in complete sensory isolation, you still have a gist of time passing. Would this be the same?

Even if I could not perceive time passing, Surely my appearance would be an event,a moment where something changed. Change is impossible without time for it to happen.

I am aware that no one would survive such conditions like an event horizon ,but humour me. Thanks!

 

[phinds]

Firstly, I don't know where to put this. Sorry if it's in the wrong place.

I was thinking about being past an event horizon, and recalled that time stops in such a place

No, it does not

and physics breaks down.

No, it does not.

 

[mfb]

Physics does not break down at the event horizon.
Some coordinate systems break down - but that is purely an issue of the mathematical description, and we have coordinate systems that work properly there. This is analogous to your longitude if you are exactly at the North Pole. It is undefined. That doesn't mean the Earth breaks apart there. If you walk over the North Pole, you don't even notice anything unusual, because the undefined longitude is purely a mathematical issue without physical relevance.

Atoms can cross the event horizon normally. This includes humans, which are very complex arrangements of many atoms. There is nothing special about humans.

I am aware that no one would survive such conditions like an event horizon

If the black hole is large enough, you can probably cross the event horizon safely. You just cannot go back, and you will hit the center soon.

Physics as we know it does break down at the center. That center is a point, or at least something extremely small - you can't be there as human anyway.

 

[PeterDonis]

That center is a point, or at least something extremely small

Actually it is a moment of time. So it's not properly thought of as a "place" of any sort.

 

[timmdeeg]

Actually it is a moment of time. So it's not properly thought of as a "place" of any sort.

I think here you refer to what GR predicts, the point. Whereas if the center is "something extremely small" (what QG perhaps might predict sometime) as mfb mentioned then presumably it is a place. Kindly correct if wrong.

 

[mfb]

Well, we don't know what is there. That includes the question what exactly "there" even means in spacetime. But this is a B-level thread, I tried to keep it simple.

 

[jbriggs444]

I think here you refer to what GR predicts, the point. Whereas if the center is "something extremely small" (what QG perhaps might predict sometime) as mfb mentioned then presumably it is a place. Kindly correct if wrong.

If quantum gravity manages to extend general relativity and eliminate its singularities, one possibility is that it will do so by explaining the notions of "time" and "position" as emergent properties of some underlying reality. In that case, the "moment in time" description that we use in the language of general relativity will still be approximately applicable and the "position in space" description will still not be.

 

[BL4CKB0X97]

Actually it is a moment of time. So it's not properly thought of as a "place" of any sort.

This post has confused me. I have not heard of this,but my knowledge is very limited.

How is it a moment in time but not a place?

If it is not a place, does this mean it has-for want of a better word- lost the other three dimensions?

To everyone, your posts have really helped me. I have little education at the moment, which is why I am hear. To be told I am wrong (with evidence,of course) is as much a victory as being right. One more mistake I will never make again.

 

[Ibix]

The singularity in a black hole isn't a point at the centre. It lies in the future of any object crossing the event horizon. In a sense, this is the reason you can't escape a black hole. Once you've crossed the event horizon you can't avoid the singularity any more than you can avoid tomorrow morning out here.

 

[phinds]

This post has confused me. I have not heard of this,but my knowledge is very limited.

How is it a moment in time but not a place?

Yeah, this one makes my head hurt too. Once you are inside the Event Horizon of a BH, your world-line ends at the singularity. That is, the singularity is in your future regardless of any physical motion you attempt to make. I can't explain it, really, I"m just regurgitating what I've heard here, but I'm sure @PeterDonis will give you a good explanation.

 

[jbriggs444]

This post has confused me. I have not heard of this,but my knowledge is very limited.

How is it a moment in time but not a place?

There are a lot of posts in these forums with various plain language descriptions that try to meaningfully capture the notion. It is hard to wrap one's head around.

The way I understand it, the idea is that if you are inside the horizon, the singularity is not so much a place -- no matter where you go in space, you will still arrive at the singularity. It is a moment in time -- it is in your inevitable future.

However, the above is not quite right. If for no other reason than that the "singularity" is neither a time nor a place. It is a feature of the mathematical description. Like the asymptote to the function $y=\frac{1}{x^2}$. To speak by analogy, the singularity is not a point on the graph. It is a feature of the graph.

 

[BL4CKB0X97]

However, the above is not quite right. If for no other reason than that the "singularity" is neither a time nor a place. It is a feature of the mathematical description. Like the asymptote to the function $y=\frac{1}{x^2}$. To speak by analogy, the singularity is not a point on the graph. It is a feature of the graph.

That I get. Thanks.

 

[BL4CKB0X97]

Another question that just popped up. Would it be light or dark beyond the event horizon,hypothetically?

I can see how both could be correct, but I'm not sure what is.

 

[phinds]

Another question that just popped up. Would it be light or dark beyond the event horizon,hypothetically?

I can see how both could be correct, but I'm not sure what is.

When you pass the EH of a supermassive BH, very little happens at the EH except that you can't get back out. You can still see objects that are outward from the EH

 

[BL4CKB0X97]

When you pass the EH of a supermassive BH, very little happens at the EH except that you can't get back out. You can still see objects that are outward from the EH

So inside the EH it would be pitch black?

 

[jbriggs444]

So inside the EH it would be pitch black?

Light from the outside stars still shines in. Light generated from the the reading lamp in your space capsule still illuminates the copy of Treasure Island that you will never finish reading. The fact that your tail lights will never be seen from outside the EH does not mean that it must be dark inside.

That said, I do not recall the red shift situation for an observer who has freely fallen from infinity as he gazes back at the outside stars.

 

[BL4CKB0X97]

Light from the outside stars still shines in. Light generated from the the reading lamp in your space capsule still illuminates the copy of Treasure Island that you will never finish reading. The fact that your tail lights will never be seen from outside the EH does not mean that it must be dark inside.

That said, I do not recall the red shift situation for an observer who has freely fallen from infinity as he gazes back at the outside stars.

I was meaning about outside the capsule, not the light that you introduce but the space itself. Space is black this side of the EH, but with all the matter and light being pulled in the EH, but it be bright and hot or dark and cold?
A similar question to what you would see going FTL.

Probably another stupid question poorly asked but asked it is nonetheless.

 

[timmdeeg]

If quantum gravity manages to extend general relativity and eliminate its singularities, one possibility is that it will do so by explaining the notions of "time" and "position" as emergent properties of some underlying reality. In that case, the "moment in time" description that we use in the language of general relativity will still be approximately applicable and the "position in space" description will still not be.

Hm, I'm just speculating now. Let's consider the center of a black hole as a hot and dense area of Planck density. Then particles entering the black hole from different sides will enter said area at different locations, describable by different coordinates. Also, as this area has a finite volume one could think of a thermal equilibrium to exist, allowing diffusion processes without time limit. Sure, the latter point is highly speculative, as we don't know the state of matter under such conditions.

 

[mfb]

I was meaning about outside the capsule, not the light that you introduce but the space itself.

See above: You still see stars. They appear a bit blueshifted and brighter redshifted and dimmer than before.

A similar question to what you would see going FTL.

"What would the laws of physics predict if these laws do not apply" is a meaningless question.

 

[timmdeeg]

See above: You still see stars. They appear a bit blueshifted and brighter than before.

They appear a bit redshifted (due to the Doppler-effect) to the free faller. A stationary observer outside the horizon will see them blueshifted.

 

[mfb]

You are right, red, not blue. Up to a factor 2.
Anyway, the main point: you would still see stars.

 

[BL4CKB0X97]

Thanks guys

 

[BL4CKB0X97]

You are right, red, not blue. Up to a factor 2.
Anyway, the main point: you would still see stars.

I assumed that gravity sostrong that light cannot escape would tear the stars apart past the EH.

 

[Ibix]

I assumed that gravity sostrong that light cannot escape would tear the stars apart past the EH.

It almost[1] certainly would destroy stars that fell in. Doesn't stop you seeing light from the stars outside.

[1] I haven't done the maths to see how large a black hole would have to be to not have destructive tidal effects across an infalling star at the event horizon. Probably implausibly large.

 

[mfb]

I assumed that gravity sostrong that light cannot escape would tear the stars apart past the EH.

I thought we were talking about starlight, not whole stars.

Supermassive black holes could be large enough to have whole stars fall in before they get ripped apart from tidal forces.

 

[BL4CKB0X97]

I thought we were talking about starlight, not whole stars.

Supermassive black holes could be large enough to have whole stars fall in before they get ripped apart from tidal forces.

I was meaning anything that would emit or reflect light. I wondered if the inside if an EH would be dark like space, which I believe I am right in thinking is dark not because of the lack of light sources, lack of stuff to actually see/for the photons to come into contact. A vacuum. Or if it was light because of the volume of matter/light sources-or would the black hole make it so you wouldn't see the light anyway. I hope I explained well enough, I struggle to word my thoughts.

 

[Ibix]

Locally, there's nothing special about the inside of a black hole compared to anywhere else. It'll be dark in the same sense that space is dark - there may be visible stars and there's always the cosmic microwave background, but the hole itself does not glow or reflect or anything. You won't get any Stargate-like effects. For a sufficiently large isolated black hole, you can fall through the event horizon without noticing anything unusual. Eventually tidal forces will shred you, but until then it's just like being in space anywhere else. Although at a redshift of two, I suspect you'd notice that the distribution of stars across the sky was rather non-uniform.

 

[BL4CKB0X97]

Locally, there's nothing special about the inside of a black hole compared to anywhere else. It'll be dark in the same sense that space is dark - there may be visible stars and there's always the cosmic microwave background, but the hole itself does not glow or reflect or anything. You won't get any Stargate-like effects. For a sufficiently large isolated black hole, you can fall through the event horizon without noticing anything unusual. Eventually tidal forces will shred you, but until then it's just like being in space anywhere else. Although at a redshift of two, I suspect you'd notice that the distribution of stars across the sky was rather non-uniform.

The perfect answer, thanks!

 

[mfb]

Although at a redshift of two, I suspect you'd notice that the distribution of stars across the sky was rather non-uniform.

The solid angle where you see stars gets smaller the deeper/later you get.

 

[PeterDonis]

I think here you refer to what GR predicts, the point.

GR doesn't predict a point. The locus $r = 0$ in the Schwarzschild solution is a spacelike line. The best short ordinary language phrase that describes that is "a moment of time".

Whereas if the center is "something extremely small" (what QG perhaps might predict sometime) as mfb mentioned then presumably it is a place.

If quantum gravity effects are only significant near $r = 0$ (i.e., for values of $r$ much less than $2M$), then the center cannot be a place, because curves of constant $r$ inside the horizon are spacelike, not timelike, and only a timelike curve can describe a "place".

If quantum gravity effects are significant enough to possibly prevent an event horizon from ever forming (i.e., for values of $r$ around $2M$), then there might not be a "center" in the usual sense at all, and if there is, we don't know enough about the geometry to know what it is like. It could be a "place" in this case, yes--or, to put it another way, curves of constant $r$ in such a solution could be timelike all the way down to $r = 0$ (as they are in, for example, flat Minkowski spacetime).

If you want to discuss such a model, you will need to find a specific reference that proposes one and ask about it.

I'm just speculating now.

Personal speculations are off topic here. There is literature on possible models of this sort. Please read it, and pose questions about it if necessary. Trying to construct your own model--particularly in a "B" level thread where you are using no math whatsoever--is not a fruitful way to proceed.

 

[PeterDonis]

How is it a moment in time but not a place?

This is really not a "B" level question (the "B" level response is what I already said), but I'll give a short answer here, and if you want more, please start a new thread.

The more technical way of saying "moment of time" in GR is "spacelike surface" (where "surface" can be a 1-dimensional, 2-dimensional, or 3-dimensional set of points, and "spacelike" means any two points in the set are spacelike separated from each other). The more technical way of saying "place" in GR is "timelike curve"--i.e., you have to be able to imagine some observer sitting at rest in the "place" in question, and the timelike curve describing the "place" is that observer's worldline.

The set of points with $r = 0$ in the Schwarzschild geometry is a spacelike line. So, using the above translation manual, it is a "moment of time", and not a "place".

 

[PeterDonis]

I do not recall the red shift situation for an observer who has freely fallen from infinity as he gazes back at the outside stars

The light he sees coming into him from the stars is more and more redshifted as he falls; the redshift factor is 2 at the horizon and increases without bound as the singularity is approached.

 

[BL4CKB0X97]

This is really not a "B" level question (the "B" level response is what I already said), but I'll give a short answer here, and if you want more, please start a new thread

I had no idea what the letters meant. What should I post it under. I have no aversion to complex mathematics, it will just give me something to work out. I learn better when given a sheet of maths I don't understand and need to find out what it means. I enjoy it.

Also, does anyone know of some reading material that I should read(related to this thread) GR and Schwarzschild is being mentioned but I leave that to the guys who have had an advanced education. i assume you'll know the best stuff to read.

 

[BL4CKB0X97]

Also, I found this in Roger Penrose's book The Road To Reality.

I apologise for the orientation. It replicates some of what you are all saying. But it poses another question, I assumed black holes where spherical,is this not the case or is it just to make it easier to understand?
http://imgur.com/RYzbg4c

 

[timmdeeg]

If quantum gravity effects are only significant near $r = 0$ (i.e., for values of $r$ much less than $2M$), then the center cannot be a place, because curves of constant $r$ inside the horizon are spacelike, not timelike, and only a timelike curve can describe a "place".

Thanks, good to know. So timelike and lightlike worldlines with decreasing $r$ are not sufficient to describe a "place". For this - if I understand it correctly now - any two points within a spacetime patch have to be separated timelike. Kindly correct if wrong.

Personal speculations are off topic here.

I am sorry, I should have remembered this.