Religion and Ethics Forum
General Category => Science and Technology => Topic started by: Walt Zingmatilder on July 27, 2020, 12:43:51 AM
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If the Universe were infinitely old would it have undergone heat death an infinitely long time ago?
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If the Universe were infinitely old would it have undergone heat death an infinitely long time ago?
If it was in it's current obsevable state, I would guess yes.
But we don't know the physics of the singularity from which it came, so from that I would say, don't know.
We don't know if it is part of a bigger reality, and if it is, we don't know the physics pertaining to that, so if that is correct I would say, don't know.
We could speculate though, that might be fun?
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As I understand it, that rather depends on exactly how time came about in the very early stages presaging the Big Bang - if time settled in slowly then the further back you go the more drawn out time is until it's a static point. Sort of the temporal equivalent of the theoretically infinite mass point in a singularity/black hole (which may, itself, have a static relative time function given the potentially infinite mass).
It's not a theoretical view that's had a lot of air-time recently, so I'm not that up to speed perhaps on all the variant ideas.
O.
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OK.
So we start with this tiny entity containing the substance of everything that is going to be.
It has either been rattling away or doing nothing for either an infinity of time or no time at all. In other words it has either been an actual universe or a potential universe.
What I think is more certain is that it is maximally ordered and given that it will spend probably an infinity in heat death that ordering might be to a fantastic degree or not as the case may be.And this I would hazard is the central mystery.
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As I understand it, that rather depends on exactly how time came about in the very early stages presaging the Big Bang - if time settled in slowly then the further back you go the more drawn out time is until it's a static point. Sort of the temporal equivalent of the theoretically infinite mass point in a singularity/black hole (which may, itself, have a static relative time function given the potentially infinite mass).
It's not a theoretical view that's had a lot of air-time recently, so I'm not that up to speed perhaps on all the variant ideas.
O.
Thanks yes I think I see that.
Aren't actual singularities frowned on by some though?
Howevermulling things over theoretically slowing time down to a stop helps us to a better analysis. Well done.
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Is stopped time actually time? I suspect it isn't.
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Thanks yes I think I see that.
I'm glad you do! :) Seriously, I sort of get the idea, but trying to actually conceive of the implications can be an absolute rabbit-hole.
Aren't actual singularities frowned on by some though?
They are, but it's where the maths leads... right up until the point where the strict maths starts to fail. If your answer ends up being 'infinity' in maths then there's some mathematicians who'd say 'fine' and others who'd say 'we haven't got the right starting information'...
O.
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They are, but it's where the maths leads... right up until the point where the strict maths starts to fail. If your answer ends up being 'infinity' in maths then there's some mathematicians who'd say 'fine' and others who'd say 'we haven't got the right starting information'...
O.
I'm interpreting this to mean maths failing to describe physical reality. Would I be right?
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I'm interpreting this to mean maths failing to describe physical reality. Would I be right?
That's the opinion of at least some of the people who say that if the answer's come out as infinity then we've not understood the question right, I think. Others will say that we've understood, but that our maths is based in one paradigm and we're trying to apply it to another, which is a different example of it not depicting the reality, of course.
O.
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As you know I have been quite keen on the idea of actual infinities not producing anything. So when I find myself presented with a moment that is infinite, I find it easy to think it isnt therefore, definitionally time and also find it hard to see how actual time could proceed out of it.
Mathematically it might therefore be easy to conceive but looked at another way it is hard to go forward from an infinitely arrested moment.
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As you know I have been quite keen on the idea of actual infinities not producing anything. So when I find myself presented with a moment that is infinite, I find it easy to think it isnt therefore, definitionally time and also find it hard to see how actual time could proceed out of it.
One of the problems is that our cognitive architecture has both evolved generally, and been individually specifically trained, entirely within finite environments, so we have no framework to truly try to comprehend the implications of infinity, the best we can do is attempt to keep track of it through a separate mechanism like maths. That lack of any mental framework to sit it neatly within makes it 'feel' somehow different, and that can contribute to the impression that it's impossible - which unfortunately we lack the sophistication in either maths or physics to definitively prove one way or the other.
Mathematically it might therefore be easy to conceive but looked at another way it is hard to go forward from an infinitely arrested moment.
It is hard, but the alternative is to try to comprehend activity prior to time existing, and our mental framework is just as poorly-equipped to try to deal with existence without time as it is existence with infinity.
O.
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One of the problems is that our cognitive architecture has both evolved generally, and been individually specifically trained, entirely within finite environments, so we have no framework to truly try to comprehend the implications of infinity, the best we can do is attempt to keep track of it through a separate mechanism like maths. That lack of any mental framework to sit it neatly within makes it 'feel' somehow different, and that can contribute to the impression that it's impossible - which unfortunately we lack the sophistication in either maths or physics to definitively prove one way or the other.
It is hard, but the alternative is to try to comprehend activity prior to time existing, and our mental framework is just as poorly-equipped to try to deal with existence without time as it is existence with infinity.
O.
You seem to be dodging the issue of proposing time slowing down to an infinitely arrested moment that, if it is stopped is probably neither infinite nor time.
It seemed easy for you to get there but now you are saying it is impossible for our pretty little heads to get from this moment to time.
Now by saying we cannot work this out is tantamount to mysticism which I am not against but which you guys are meant to disapprove of.
Either dont call mysticism or dont complain when somebody else does.
To get back to thinking this through.
Either this infinite temporal singularity is wrong or we can get somewhere with it
If it frozen time exists then we are looking for something either about it or external to it to get it rolling.
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You seem to be dodging the issue of proposing time slowing down to an infinitely arrested moment that, if it is stopped is probably neither infinite nor time.
Wow, that escalated quickly. There we were having a nice conversation about the conceptual limitations of human psychology and neurology and suddenly we're into accusations of a lack of integrity - always assume incompetence for you jump to malice, surely you know at least that by now.
As to whether I'm 'ducking' the issue - it's not something I personally hold to as a concept anyway, I'm comfortable with the idea that our universe probably started in the period immediately before the Big Bang, so I don't have the issue to 'duck' in the first place.
It seemed easy for you to get there but now you are saying it is impossible for our pretty little heads to get from this moment to time.
I didn't 'get there' - you got there, you started there, you called the thread 'the infinitely old universe'. As to whether it's impossible for us to get our heads round... is that not a valid point about the limitations of human understanding?
Now by saying we cannot work this out is tantamount to mysticism which I am not against but which you guys are meant to disapprove of.
Which 'guys'? I'm not anyone's authorised spokesman. However, there is a world of difference between 'the maths resolves to this, which might be right or might the limitation of our current mathematics' and 'we don't know, therefore gods did it'. One of those is mysticism, one of those is an acceptance of fallibility and an openness about the current limitations of our understanding.
Or, to put it bluntly, one is 'integrity' and the other is 'pretending to know the answer'.
Either dont call mysticism or dont complain when somebody else does.
Either learn the subtle distinctions between 'we don't know everything, here's where our current knowledge ends' and 'we don't know anything, but we're going to say it's this, now pass that collection plate along'.
To get back to thinking this through.
Are you sure, you seemed to be enjoying the snideness more than the being wrong?
Either this infinite temporal singularity is wrong or we can get somewhere with it
Or both.
If it frozen time exists then we are looking for something either about it or external to it to get it rolling.
Maybe. If it's frozen time from our perspective, that doesn't necessarily tell us very much about time from its perspective, given that time is relative to at least speed (possibly just within the universe), mass (possibly just within the universe) and theoretically other factors of which we're not currently aware. It may be that time has multiple vectors and it only began moving in ours due to some event in another vector - our appreciation of what time is is almost as limited as our understanding of infinity.
O.
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Wow, that escalated quickly. There we were having a nice conversation about the conceptual limitations of human psychology and neurology and suddenly we're into accusations of a lack of integrity - always assume incompetence for you jump to malice, surely you know at least that by now.
As to whether I'm 'ducking' the issue - it's not something I personally hold to as a concept anyway, I'm comfortable with the idea that our universe probably started in the period immediately before the Big Bang, so I don't have the issue to 'duck' in the first place.
I didn't 'get there' - you got there, you started there, you called the thread 'the infinitely old universe'. As to whether it's impossible for us to get our heads round... is that not a valid point about the limitations of human understanding?
Which 'guys'? I'm not anyone's authorised spokesman. However, there is a world of difference between 'the maths resolves to this, which might be right or might the limitation of our current mathematics' and 'we don't know, therefore gods did it'. One of those is mysticism, one of those is an acceptance of fallibility and an openness about the current limitations of our understanding.
Or, to put it bluntly, one is 'integrity' and the other is 'pretending to know the answer'.
Either learn the subtle distinctions between 'we don't know everything, here's where our current knowledge ends' and 'we don't know anything, but we're going to say it's this, now pass that collection plate along'.
Are you sure, you seemed to be enjoying the snideness more than the being wrong?
Or both.
Maybe. If it's frozen time from our perspective, that doesn't necessarily tell us very much about time from its perspective, given that time is relative to at least speed (possibly just within the universe), mass (possibly just within the universe) and theoretically other factors of which we're not currently aware. It may be that time has multiple vectors and it only began moving in ours due to some event in another vector - our appreciation of what time is is almost as limited as our understanding of infinity.
O.
My apologies
I thought I was seeing "mathematics can arrive at infinities and we can envisage real ,actual infinities"and " our brains arent evolved to cope with infinities" in the same breath as it were and just lost it entirely.
Since this singularity is what we all used to be and that includes the universe is it at all legitimate to talk about a relative position.
Since we are talking about relative positions what is it that the proto universe is relative to for time to be frozen.
Are you saying it is frozen for some notional external observer but not for the universe itself?
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My apologies
I thought I was seeing "mathematics can arrive at infinities and we can envisage real ,actual infinities"and " our brains arent evolved to cope with infinities" in the same breath as it were and just lost it entirely.
:)
Since this singularity is what we all used to be and that includes the universe is it at all legitimate to talk about a relative position.
In terms of space-time, yes - even if we can't easily differentiate any potential change in three-dimensional space, we've moved in time.
Since we are talking about relative positions what is it that the proto universe is relative to for time to be frozen.
If that idea of time being multi-dimensional and us only manifesting (so far as we can tell at the moment) in one of them, it's a possibility but so far as I know it's absolutely nothing more than mere conjecture, I don't know of anything evidentiary that even hints at it.
Are you saying it is frozen for some notional external observer but not for the universe itself?
It's more that at the very, very core of it, with infinite mass, time is static. At the fringes of that infinite core, as it starts to 'unravel', part of that unravelling process is the very, very slow emergence of time, and as we get further away from that infinite mass in space-time so time speeds up. If this is the case then, given enough detectors over large enough percentage of the expanse of the universe, it might be possible to detect variations in the rate of the passage of time and work back to determine the 'centre' from which everything came, presuming that expansion was uniform (which isn't I believe guaranteed).
O.
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:)
In terms of space-time, yes - even if we can't easily differentiate any potential change in three-dimensional space, we've moved in time.
So you are saying that infinitely slowed time is not stopped?
We are still only considering time. Are you proposing energy and matter at this stage.
We still have the question of why it suddenly goes from being non dimensional to now being possibly multidimensional.If that idea of time being multi-dimensional and us only manifesting (so far as we can tell at the moment) in one of them, it's a possibility but so far as I know it's absolutely nothing more than mere conjecture, I don't know of anything evidentiary that even hints at it.
OK It's more that at the very, very core of it, with infinite mass, time is static. At the fringes of that infinite core, as it starts to 'unravel', part of that unravelling process is the very, very slow emergence of time, and as we get further away from that infinite mass in space-time so time speeds up. If this is the case then, given enough detectors over large enough percentage of the expanse of the universe, it might be possible to detect variations in the rate of the passage of time and work back to determine the 'centre' from which everything came, presuming that expansion was uniform (which isn't I believe guaranteed).
Ok I can see something like this working in the universe....something like a black hole. But That type of thing cannot have infinite mass because it is a thing in the universe. The universe itself would have been that infinite core. There are two questions here or maybe they are the same question firstly How does it change its state if it is entirely infinite core as it were. And secondly how can there be any fringes and activity within them? What are you suggesting is beyond the fringe?
I hate to say it but I think I'm glimpsing that the term infinite here is causing our theoretical universe problems getting moving. Too early to say "I told you so"!though.
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So you are saying that infinitely slowed time is not stopped?
Time is relative, so whilst time might (or might not) stop at a point of infinite mass, at a distance time might continue.
We are still only considering time. Are you proposing energy and matter at this stage.
We're talking about proximity to mass, so we must be considering energy/matter in some form as I understand it.
We still have the question of why it suddenly goes from being non dimensional to now being possibly multidimensional.
Absolutely, just one of the reasons I find it harder to accept this explanation, because in the middle of this where everything's supposed to be time would be theoretically stagnant so I can't see how you'd have anything changing to bring about longer-term changes like the Big Bang - it's possible something else could impinge upon it from outside, but then that 'area' needs time or a corollary anyway.
OK Ok I can see something like this working in the universe....something like a black hole. But That type of thing cannot have infinite mass because it is a thing in the universe.
Except that the mass is distorting the space/time and gravity around it, so our usual 'methods' for determining something's mass start to break down. If you compress a finite mass into a infinitessimally small space you have infinite density... which implies infinite mass. Like I said, when you start to deal with infinities, maths starts to break down.
The universe itself would have been that infinite core.
As I understand the idea, yes.
There are two questions here or maybe they are the same question firstly How does it change its state if it is entirely infinite core as it were.
That's my issue with the theory, but as I said it could be reliant on external forces (or, perhaps, something like the spontaneous quantum foam breakdown, but my understanding of that is that it requires a timeframe as well).
And secondly how can there be any fringes and activity within them?
What represents the 'fringe' and what the 'core' isn't well defined as I recall, but I think it's supposed to be something that develops as the expansion starts - I'm part conjecturing and part trying to recall bits and pieces I've read here and there.
What are you suggesting is beyond the fringe?
I don't recall reading anything linked to this that posited anything particular about anything outside the universe; we've already had conversations elsewhere about my take on some of the possibilities presented by an extra-universal physics.
I hate to say it but I think I'm glimpsing that the term infinite here is causing our theoretical universe problems getting moving. Too early to say "I told you so"!though.
I'm not sure it's the infinities here that are causing the issue, although they highlight it, it's trying to take universal rules and go back to a pre-universal point, realising that doesn't work and trying to find a way to make the universe eternal rather than having to fall back on conjecture about what might be 'outside' of it.
O.
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Time is relative, so whilst time might (or might not) stop at a point of infinite mass, at a distance time might continue.
Can we contemplate everything as a non dimensional point AND distance? Not sure.
Infinite mass........how did that get there? Wouldn't it all just work with the tiniest of masses?We're talking about proximity to mass, so we must be considering energy/matter in some form as I understand it.
Absolutely, just one of the reasons I find it harder to accept this explanation, because in the middle of this where everything's supposed to be time would be theoretically stagnant so I can't see how you'd have anything changing to bring about longer-term changes like the Big Bang - it's possible something else could impinge upon it from outside, but then that 'area' needs time or a corollary anyway.
It seems to me that we have introduced infinite mass merely in order to engineer infinite time. As a theory for the origin of stuff that on the face of it isnt a good look. Indeed our beginning which incidentally I take equal responsibility for resembles the end of something.....like a back hole.And thus we are in big bounce territory......from which we are back to deducing an infinity.Except that the mass is distorting the space/time and gravity around it, so our usual 'methods' for determining something's mass start to break down. If you compress a finite mass into a infinitessimally small space you have infinite density... which implies infinite mass. Like I said, when you start to deal with infinities, maths starts to break down.
Well you know how I feel about infinities.....in terms of maths breaking down...Do I believe that maths has or is it's own reality? Sure....Do I believe that physics breaks down around something like this yes.....do I think maths breaks down?You'll need to explain that.
However we need a kind of key to take the wheel clamps off our static universe and I may have just glimpsed one in a statement of yours.
Finite mass in infinite small space leading to infinite density implying infinite mass. Now that is either the wrongest thing you've said today. Or it is a blindingly brilliant way of getting something for nothing.
That's my issue with the theory, but as I said it could be reliant on external forces (or, perhaps, something like the spontaneous quantum foam breakdown, but my understanding of that is that it requires a timeframe as well).
Why is a time frame necessary here or for other unusual processes you have mentioned?
What represents the 'fringe' and what the 'core' isn't well defined as I recall, but I think it's supposed to be something that develops as the expansion starts - I'm part conjecturing and part trying to recall bits and pieces I've read here and there.
But isnt it all core.... because if we are talking about everything there is no fringeI don't recall reading anything linked to this that posited anything particular about anything outside the universe; we've already had conversations elsewhere about my take on some of the possibilities presented by an extra-universal physics.
But were they crazy enough?.....to coin a phrase.
I think talk of distances and fringes and relative means we haven't really moved beyond looking at everything as part of something else or relative to something else and that is why we are starting at what looks like the end of a process.
Does this have to be our fate?
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Can we contemplate everything as a non dimensional point AND distance? Not sure. Infinite mass........how did that get there? Wouldn't it all just work with the tiniest of masses?
As I've said, this is part of the issue when maths leads you to an answer of 'infinity', our usual methods of mathematics start to break down. As soon as you start to try to conduct arithmetic operations with infinite values your answers are properly phrased as 'undefined'.
It seems to me that we have introduced infinite mass merely in order to engineer infinite time.
It's actually somewhat the other way round - we have infinitessimal space, so we have infinite density, which results in a point-source of infinite mass which will resolve into finite mass once expansion begins... which it can't because of the static nature. As I've said, I can't see a way out of it, you end up with a static point and no way to change that because there's no prospect of any subjective time at the point of infinite mass in which to have change.
As a theory for the origin of stuff that on the face of it isnt a good look.
That's my take on it, but there are people playing around with the maths trying to find some way to resolve it.
Indeed our beginning which incidentally I take equal responsibility for resembles the end of something.....like a back hole. And thus we are in big bounce territory......from which we are back to Harding an infinity.
Black holes are not the end of something - Stephen Hawking's first great contribution to cosmology was the theory of Hawking Radiation and entropy's gradual winding down of black holes into an even distribution of energy.
Except that the mass is distorting the space/time and gravity around it, so our usual 'methods' for determining something's mass start to break down.
I don't think so - mass is what gravity works upon, as gravity changes so a particular mass' weight will change, but the mass doesn't.
Well you know how I feel about infinities.....in terms of maths breaking down...Do I believe that maths has or is it's own reality? Sure....Do I believe that physics breaks down around something like this yes.....do I think maths breaks down?You'll need to explain that.
Maths is on of the tools we use to try to define reality - where it breaks down it's because we've failed to either model the reality in order for the maths to work, or we've failed to adequately advance the maths to handle the reality.
However we need a kind of key to take the wheel clamps off our static universe and I may have just glimpsed one in a statement of yours.
Finite mass in infinite small space leading to infinite density implying infinite mass. Now that is either the wrongest thing you've said today. Or it is a blindingly brilliant way of getting something for nothing.
If you have no space, and that's filled with mass, you have infinite mass. It's a countable infinity, but it's infinite - maths is weird.
Why is a time frame necessary here or for other unusual processes you have mentioned? But isnt it all core.... because if we are talking about everything there is no fringe But were they crazy enough?.....to coin a phrase.
At the risk of getting repetitive, I don't know, that's part of what makes it an idea that I have difficulty accepting.
I think talk of distances and fringes and relative means we haven't really moved beyond looking at everything as part of something else or relative to something else and that is why we are starting at what looks like the end of a process.
To an extent we are - we are trying to interpolate back from the current universe to what might have been at that point.
Does this have to be our fate?
What the future holds is already determined, but I don't know if this is the looking glass that shows us what it is.
O.
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If the Universe were infinitely old would it have undergone heat death an infinitely long time ago?
Possibly, however:
- We don't know everything about physics.
- There are cyclic models such as conformal cyclic cosmology (https://en.wikipedia.org/wiki/Conformal_cyclic_cosmology) where the heat death of one universe leads directly to another big bang.
- Entropy is a statistical law, if there is an infinite amount of time, you'll spontaneously get any amount of order occurring an infinite number of times, purely by chance.
- This bubble of space-time might only be part of a larger context which is infinitely old.
- Something else nobody has even thought of yet.
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It's actually somewhat the other way round - we have infinitessimal space, so we have infinite density, which results in a point-source of infinite mass which will resolve into finite mass once expansion begins... which it can't because of the static nature. As I've said, I can't see a way out of it, you end up with a static point and no way to change that because there's no prospect of any subjective time at the point of infinite mass in which to have change.
That's my take on it, but there are people playing around with the maths trying to find some way to resolve it.
Black holes are not the end of something - Stephen Hawking's first great contribution to cosmology was the theory of Hawking Radiation and entropy's gradual winding down of black holes into an even distribution of energy.
I don't think so - mass is what gravity works upon, as gravity changes so a particular mass' weight will change, but the mass doesn't.
Maths is on of the tools we use to try to define reality - where it breaks down it's because we've failed to either model the reality in order for the maths to work, or we've failed to adequately advance the maths to handle the reality.
If you have no space, and that's filled with mass, you have infinite mass. It's a countable infinity, but it's infinite - maths is weird
I’m forced to agree with you at this stage.
Would our singularity universe not also be subject to Hawking radiation having maximal potential for entropy?
So I’m thinking here of time equating to entropy.
Please shoot me down if necessary.
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I’m forced to agree with you at this stage.
Be still my beating heart!
Would our singularity universe not also be subject to Hawking radiation having maximal potential for entropy?
I don't know - if there's no time, then there's no breakdown of anti-particles at the event horizon to emit the radiation - entropy is our explanation of a feature of the universe moving through time, I think, and if it's not moving through time then I don't know if would happen. I don't know to what extent this singularity might or might not differ from the singularities envisioned in black holes, I'm afraid.
So I’m thinking here of time equating to entropy. Please shoot me down if necessary.
I don't think it's 'shooting down', we're all reaching a bit at least, here. I don't think time equates to entropy, so much as in the grand scheme entropy is an inevitable consequence of time; we know that it's not a linear relationship, though, so there's some possibility of it being disrupted, though I'm not sure by what.
O.
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Possibly, however:
- We don't know everything about physics.
Agreed.- There are cyclic models such as conformal cyclic cosmology (https://en.wikipedia.org/wiki/Conformal_cyclic_cosmology) where the heat death of one universe leads directly to another big bang.
Call me old fashioned but what is it that keeps this perpetual motion machine going? Why is this system not subject to heat death.- Entropy is a statistical law, if there is an infinite amount of time, you'll spontaneously get any amount of order occurring an infinite number of times, purely by chance.
Trouble is we need a real life infinity also it may be argued that this order of energy, if enough to start a universe is going to get less and less each universe. However the idea of entropy being probabilistic does raise the intriguing idea that the universe could suffer instantaneous heat death if what you say is true.
Therefore the whole system runs down to heat death. What is heat death anyway? The loss of the ability to do useful work.- This bubble of space-time might only be part of a larger context which is infinitely old.
It May.
- Something else nobody has even thought of yet.
ditto.
[/list]
[/quote]Ditto.
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Agreed. Call me old fashioned but what is it that keeps this perpetual motion machine going? Why is this system not subject to heat death.Trouble is we need a real life infinity also it may be argued that this order of energy, if enough to start a universe is going to get less and less each universe. However the idea of entropy being probabilistic does raise the intriguing idea that the universe could suffer instantaneous heat death if what you say is true.
Therefore the whole system runs down to heat death. What is heat death anyway? The loss of the ability to do useful work.It May.
- Something else nobody has even thought of yet.
ditto.
Ditto.
For an obviously intelligent, and probably quite likeable, bloke, you don't half spout a lot of pretentious, incomprehensible bollocks.
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For an obviously intelligent, and probably quite likeable, bloke, you don't half spout a lot of pretentious, incomprehensible bollocks.
Hey, less of the pretentious.
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Call me old fashioned but what is it that keeps this perpetual motion machine going? Why is this system not subject to heat death.
I suggest that Roger Penrose (who's published papers with Stephen Hawking and who proposed the idea) has a better understanding of physics than anybody on this forum. However, it's basically about the re-scaling of the phase space of the universe. The metric of the universe at heat death is remarkably similar to that of the big bang, with the exception of the scale factor. If every particle eventually decays into massless particles (this is a conjecture), then there is no way for the universe to keep track of time or space.
Trouble is we need a real life infinity also it may be argued that this order of energy, if enough to start a universe is going to get less and less each universe. However the idea of entropy being probabilistic does raise the intriguing idea that the universe could suffer instantaneous heat death if what you say is true.
Therefore the whole system runs down to heat death. What is heat death anyway? The loss of the ability to do useful work.
I don't see any problem with a real life infinity and you suggested it in the title of this thread. You also seem to be confusing energy with entropy. The energy of the universe will always be the same*. There is no physical reason why entropy can't be reversed to any arbitrary degree, it's just very, very improbable, but given enough time, it will eventually happen, and given an infinite amount of time, it definitely will happen.
It is however true that the universe may suffer an instantaneous heat death, it's also true that, in this scenario, Boltzmann brains (https://en.wikipedia.org/wiki/Boltzmann_brain) would be far more common than entire universes. Maybe that doesn't matter, though. How would you tell if your life was a series of Boltzmann brains, each thought separated by vast amounts of time?
* Actually energy conservation is problematic in general relativity anyway.
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I suggest that Roger Penrose (who's published papers with Stephen Hawking and who proposed the idea) has a better understanding of physics than anybody on this forum. However, it's basically about the re-scaling of the phase space of the universe. The metric of the universe at heat death is remarkably similar to that of the big bang, with the exception of the scale factor. If every particle eventually decays into massless particles (this is a conjecture), then there is no way for the universe to keep track of time or space.
I don't see any problem with a real life infinity and you suggested it in the title of this thread. You also seem to be confusing energy with entropy. The energy of the universe will always be the same*. There is no physical reason why entropy can't be reversed to any arbitrary degree, it's just very, very improbable, but given enough time, it will eventually happen, and given an infinite amount of time, it definitely will happen.
It is however true that the universe may suffer an instantaneous heat death, it's also true that, in this scenario, Boltzmann brains (https://en.wikipedia.org/wiki/Boltzmann_brain) would be far more common than entire universes. Maybe that doesn't matter, though. How would you tell if your life was a series of Boltzmann brains, each thought separated by vast amounts of time?
* Actually energy conservation is problematic in general relativity anyway.
I can’t fault anything here. A thread considering what you say about Boltzmann brains might be entertaining.
I have one question. How much quantum tunnelling has to happen to restore maximal order for a new Big Bang? Is it the whole universe?
Does every photon of energy remaining have to tunnel at the same time?And to the same place or state as it were?
What is the smallest unit that energy will break down into?
Isn’t the spontaneous formation of parts of universes more likely than the formation of the pre Big Bang singularity?
I know that this does not affect the likely hood of these events happening. I’m just wondering if a new Big Bang has to contain all of the remains of the previous one.
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I have one question.
I counted six.
Is that the same as "I only had one drink"?
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I counted six.
Fffffffff..........no I mustn’t........... .gehhhhh........no I shouldn’t.........Oh shit I can’t keep it in.....
Sebastian my dear friend......Have you considered getting a life?
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I can’t fault anything here. A thread considering what you say about Boltzmann brains might be entertaining.
I have one question. How much quantum tunnelling has to happen to restore maximal order for a new Big Bang? Is it the whole universe?
Does every photon of energy remaining have to tunnel at the same time?And to the same place or state as it were?
What is the smallest unit that energy will break down into?
Isn’t the spontaneous formation of parts of universes more likely than the formation of the pre Big Bang singularity?
I know that this does not affect the likely hood of these events happening. I’m just wondering if a new Big Bang has to contain all of the remains of the previous one.
Sorry, I don't understand why you think this has anything to do with tunnelling.
The notion is based on relativity, rather than quantum mechanics. It's just that the mathematical description of a universe filled with entirely with massless particles (hence, all travelling at light speed) is remarkably similar to that of the earliest moments of this universe and with everything travelling at light speed, there is nothing that can keep track of time or distance.
Added: That was about conformal cyclic cosmology, the reversal of entropy is just statistical, it has nothing to do with tunnelling either.
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Sorry, I don't understand why you think this has anything to do with tunnelling.
The notion is based on relativity, rather than quantum mechanics. It's just that the mathematical description of a universe filled with entirely with massless particles (hence, all travelling at light speed) is remarkably similar to that of the earliest moments of this universe and with everything travelling at light speed, there is nothing that can keep track of time or distance.
Added: That was about conformal cyclic cosmology, the reversal of entropy is just statistical, it has nothing to do with tunnelling either.
Alright forget tunnelling for the time being.
How do you propose getting every thinly distributed piece of energy across infinite distances to form a maximally ordered pre Big Bang singularity? It doesn’t sound as if even light speed is going to do the job and if mass has gone, no Big Crunch either.
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Alright forget tunnelling for the time being.
How do you propose getting every thinly distributed piece of energy across infinite distances to form a maximally ordered pre Big Bang singularity? It doesn’t sound as if even light speed is going to do the job and if mass has gone, no Big Crunch either.
Firstly, I don't propose anything, I offered Penrose's conjecture as an example of how it might be possible for an infinitely old universe to exist (other conjectures are available). I don't fully (mathematically) understanding the idea, but I have to assume that somebody of Penrose's stature knows what he's talking about.
Given that, the way he describes it (see Cycles of Time (https://en.wikipedia.org/wiki/Cycles_of_Time)), it's because everything is travelling at light speed, nothing experiences either space or time, so the concepts loose any physical meaning. The metric that describes the space-time of the universe has 10 independent values and 9 of them are identical in the final stages of a universe in which everything decays to massless particles (and all black holes have evaporated due to Hawking radiation), to those of the very first moments of our universe, and the one that's different is the one that describes the spatial scale (which has become meaningless).
The idea of "maximally ordered" is also rather misleading. The entropy of the universe is not a simple matter (largely due to gravity tending to clump things together) and Penrose also suggests that what made the BB have such low entropy was simply that the Weyl curvature tensor was zero - which would also be the case at in the final stages of a universe in which everything becomes massless.
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Firstly, I don't propose anything, I offered Penrose's conjecture as an example of how it might be possible for an infinitely old universe to exist (other conjectures are available). I don't fully (mathematically) understanding the idea, but I have to assume that somebody of Penrose's stature knows what he's talking about.
Given that, the way he describes it (see Cycles of Time (https://en.wikipedia.org/wiki/Cycles_of_Time)), it's because everything is travelling at light speed, nothing experiences either space or time, so the concepts loose any physical meaning. The metric that describes the space-time of the universe has 10 independent values and 9 of them are identical in the final stages of a universe in which everything decays to massless particles (and all black holes have evaporated due to Hawking radiation), to those of the very first moments of our universe, and the one that's different is the one that describes the spatial scale (which has become meaningless).
The idea of "maximally ordered" is also rather misleading. The entropy of the universe is not a simple matter (largely due to gravity tending to clump things together) and Penrose also suggests that what made the BB have such low entropy was simply that the Weyl curvature tensor was zero - which would also be the case at in the final stages of a universe in which everything becomes massless.
Thanks for your post, very informative.