'Fine tuning' the universe...

[vlaiv]

3 minutes ago, EarthLife said:

It is indeed a huge problem for us to answer, a problem that makes the whole thing infinitely mysterious for us.

Bare in mind that the human race is far from logical, it can be good at skirting around things it can't answer

A bit like how atoms have become self aware ? .. that's what you call real high tech !  .. is it the universes way of trying to understand itself ? .. it all gets very strange very quickly, but all quite real, or is it

Philosophy tries to deal with some of it by asking questions like - how much can we know? / is there limit to the knowledge? How can we be certain that some knowledge is true and so on.

For example - can anyone be sure that sun will rise tomorrow? Something all take for granted - but there is no guarantee of that.

Similarly - if we performed experiment N times - there simply is no 100% guarantee that it will behave the same N+1. Some say that by doing things more times - we build confidence that it will happen in the same way - but there simply no way of being certain about it.

[Moonshed]

14 minutes ago, vlaiv said:

It is intrinsically unknowable.

Currently yes, but who knows what the future may bring? Maybe we will one day make contact with ET and they, possibly being in existence 3 million years longer than us, have made incredible discoveries, they even know how the universe came into existence and what existed prior to that.

We do not know what the future holds. We don’t even know if the future is already written, already out there waiting for us to reach it. Or maybe the future exists but only as a blank page waiting for us to make our mark on it.

I think time is the biggest mystery we have, once we fully understand it I’m sure that a full understanding of the creation of the universe will naturally follow. We can’t help but view time as moving along a one way street from the past to the present to the future. For any geeks interested I have written about time here. 

http://www.thekeyboard.org.uk/What is Time.htm

[Alien 13]

Man created the universe we see today, without us time has no meaning so an infinite number of universes may have existed before this one..

Alan

[vlaiv]

12 minutes ago, Moonshed said:

Currently yes, but who knows what the future may bring? Maybe we will one day make contact with ET and they, possibly being in existence 3 million years longer than us, have made incredible discoveries, they even know how the universe came into existence and what existed prior to that.

Well - that is the meaning of intrinsically unknowable - you can't know it even in principle.

If universe is defined as "everything there is", and something existed that created it - that something:

a) must not exist any more - or it must be part of this universe and hence could not have created it

b) has no connection to this universe (see a - as any "connection" can't be current connection).

If there are any "artifacts" present in this universe that tell us about what created it - it will not tell us enough to be able to distinguish it from all other things that would leave the same artifacts. Besides those artifacts - all the rest about what created universe is simply unknowable.

Then there is issue of time.

Concept of creation is tied to time - or very simple version of time - one that is just sequence of events without necessarily assigning ratio of sorts (something is "twice as old" as something else - it is enough to know what came prior to something else), but if time existed outside of the scope of our universe - then what "contains" time and how it came into being?

You see - if something caused our universe to come into existence - it must have happened before - and that implies existence of at least basic order of events - or time.

Edited March 3, 2023 by vlaiv
grammar

[EarthLife]

Chicken creates an egg, egg magically transforms itself into another chicken, first chicken eventually dies.

It would have been much more efficient to just stay as one chicken in the first place !

Edited March 3, 2023 by EarthLife

[vlaiv]

Here is an interesting idea.

If there is no time - then there is no sense in asking - what came before - as there is no before / after - those are concepts that stem from concept of time.

There is strong indication that time is nothing but illusion. Most of it comes from relativity. Fact that it is flexible and that it is sort of related to spatial dimensions creating space time is one indication.

Simultaneity of events - or rather it being tied to observer is another strong indication.

There are observers that have their "now" aligned to our past and observers that have their "now" aligned to our future. Combine that with quantum mechanics and entanglement and you get very interesting situation. We usually think that measurement in one place determines state in different place. Say that we measure spin of electrons - and measuring one will determine spin of the other, right? But what measurement was made first? That depends on frame of reference. We can either talk about hidden variables or accept that order of events does not really matter - no causality - or no time.

Then there is fact that all fundamental laws of physics are time reversible, yet time seems to flow in one direction.

Maybe we are asking the wrong questions?

 

Edited March 3, 2023 by vlaiv

[saac]

57 minutes ago, vlaiv said:

Philosophy tries to deal with some of it by asking questions like - how much can we know? / is there limit to the knowledge? How can we be certain that some knowledge is true and so on.

For example - can anyone be sure that sun will rise tomorrow? Something all take for granted - but there is no guarantee of that.

Similarly - if we performed experiment N times - there simply is no 100% guarantee that it will behave the same N+1. Some say that by doing things more times - we build confidence that it will happen in the same way - but there simply no way of being certain about it.

Yeah we can tie ourselves up with so many of these word games but to what end? 

Re tomorrow - if we arrive at one then by definition the sun has indeed risen again. As John Lennon said "everything will be alright in the end, if it is not alright  then it is not yet the end"

Confidence - in science and engineering  we don't chase 100 % confidence we satisfy ourselves by quantifying an acceptable measure of confidence. 

Truth - as it was written in that book we don't discuss "truth , what is truth?"

Jim 

 

[saac]

33 minutes ago, vlaiv said:

Here is an interesting idea.

If there is no time - then there is no sense in asking - what came before - as there is no before / after - those are concepts that stem from concept of time.

There is strong indication that time is nothing but illusion. Most of it comes from relativity. Fact that it is flexible and that it is sort of related to spatial dimensions creating space time is one indication.

Simultaneity of events - or rather it being tied to observer is another strong indication.

There are observers that have their "now" aligned to our past and observers that have their "now" aligned to our future. Combine that with quantum mechanics and entanglement and you get very interesting situation. We usually think that measurement in one place determines state in different place. Say that we measure spin of electrons - and measuring one will determine spin of the other, right? But what measurement was made first? That depends on frame of reference. We can either talk about hidden variables or accept that order of events does not really matter - no causality - or no time.

Then there is fact that all fundamental laws of physics are time reversible, yet time seems to flow in one direction.

Maybe we are asking the wrong questions?

 

There is also a line of thought within Physics that suggests time may be a quantised unit.  I find that possibility tantalizing. 

That aside, let's say for a moment that time is truly an illusion with no physical manifestation, properties  boundaries or relationship to other physical properties.  In effect time has no function or meaning to the universe. Would not the very fact that we do indeed sense time and sense a flow of time void all of that proceeding supposition.  We, our consciousness, is every bit a part of the universe (a property, while not fundamental, a property nonetheless).  In effect then the universe has indeed created time for we do sense it, our lives are measured by it; we grow old, never young, we live then die, that order is fundamental. 

Jim 

Edited March 3, 2023 by saac

[vlaiv]

34 minutes ago, saac said:

There is also a line of thought within Physics that suggests time may be a quantised unit.  I find that possibility tantalizing. 

That aside, let's say for a moment that time is truly an illusion with no physical manifestation, properties  boundaries or relationship to other physical properties.  In effect time has no function or meaning to the universe. Would not the very fact that we do indeed sense time and sense a flow of time void all of that proceeding supposition.  We, our consciousness, is every bit a part of the universe (a property, while not fundamental, a property nonetheless).  In effect then the universe has indeed created time for we do sense it, our lives are measured by it; we grow old, never young, we live then die, that order is fundamental. 

Jim 

Here is counter argument.

What about 540nm wavelength light is green?

What property does 540nm photon have that is different from 686nm photon - except for wavelength / energy? There is nothing in the wavelength or energy itself that would determine what color should be perceived as.

Why do we "perceive" one as green and other as red? Where does the color come from? Did the universe create it for us or is it just sensory artifact? Could time passage be also sensory artifact of sorts?

We never touch anything, but we all have firm (pun?) idea that we touch things. Things that we perceive as solid are in fact mostly empty space and all that anyone ever felt is electromagnetic repulsion. Yet we seem to be mesmerized and very amused when holding two magnets that repel each other. We find it very interesting as it is "action at a distance" that seems so strange to us.

Again - sensory artifact. We needed to invent tools that would paint us real picture of what the matter really is. Maybe we need to develop tools to understand that time really is, not what we sense it as?

Edited March 3, 2023 by vlaiv
so many typos for some reason ....

[andrew s]

As far as I am aware there is no experimental evidence that either space or time are quantised. Both QFT and GR, our two most successful theories, are both based on a continuous spacetime. It certainly has been looked for.

I am with Einstein that time is what clocks measure and space is what metre sticks measure.  A pragmatic operational approach that I am sure @saac will appreciate.

I have half a book case full of books about "time" accumulated over 60 yrs of pondering about the nature of time but none has been as insightful as Einstein's  position. 

There is a serious approach to time not flowing in the Block Universe where everything exists as a 4D block of all space and all time. In this Universe we just perceive time flowing as we trace out a trajectory.  Interestingly,  it's advocates claim it solves the fine tuning issue but this is challenged by others. I  have one or two books on that too😊.

Regards Andrew 

Edited March 3, 2023 by andrew s

[saac]

Yet we do indeed perceive green.  So not unreasonable to conclude that a mechanism within our photoreceptors are perhaps being excited by that particular energy level (frequency), perhaps a sympathetic absorption by a particular expressed protein in the photoreceptor (cone) sensitive to a particular wavelength (R,G,B). So we, our biology,  associate the response naming it a perception of green.   It is indeed a biological sense, and the biology is every bit an equal creation of the universe as is the proton, electric magnetic field, or mass.  Our biology does not stand outwith the universe. 

The sensation we call touch is exactly what you have described - we are sensing the repulsive force of the like charges, we do indeed sense the repulsive force and that we call touch.  If there is an incomplete or incorrect understanding of the process then it is due to the common use of the language not in the fuller description provided by the scientific interpretation.  In a similar way we talk about taking our weight when we stand on the bathroom scales but we are not measuring our weight we are measuring our mass (scales calibrated in units of mass) but to insist on that would be pedantic. 

I think in that  respect we already have a tool , we sense it ourselves. Of course we can develop tools to refine the measurement as we have with our other senses which measure pressure, force, temperature etc.  Just as we develop those tools and refined those measurements we will put a further level of understanding to our definition of time. 

Jim 

Edited March 4, 2023 by saac

[iantaylor2uk]

If space is quantized it will be at the Plank scale, which is many orders of magnitude lower than anything we can measure at the moment. I think it is quite likely that space-time is quantized as I don't think infinity has any place in physics (infinity is a mathematical concept not a physical one). The fact that continuity breaks down at  the lowest length scales also means we will end up with difference equations rather than differential equations. 

[andrew s]

3 minutes ago, iantaylor2uk said:

If space is quantized it will be at the Plank scale, which is many orders of magnitude lower than anything we can measure at the moment. I think it is quite likely that space-time is quantized as I don't think infinity has any place in physics (infinity is a mathematical concept not a physical one). The fact that continuity breaks down at  the lowest length scales also means we will end up with difference equations rather than differential equations. 

While I can't put Google on the paper but it has been tested to below the Plank scale. 

If space were quantised different wavelengths of light would travel at slightly different speeds and this would show up in the arrival time of light of different wavelengths from transient event at astronomical distances none was found.

I will look again tomorrow. 

Regards Andrew 

[saac]

37 minutes ago, andrew s said:

As far as I am aware there is no experimental evidence that either space or time are quantised. Both QFT and GR, our two most successful theories, are both based on a continuous spacetime. It certainly has been looked for.

I am with Einstein that time is what clocks measure and space is what metre sticks measure.  A pragmatic operational approach that I am sure @saac will appreciate.

I have half a book case full of books about "time" accumulated over 60 yrs of pondering about the nature of time but none has been as insightful as Einstein's  position. 

There is a serious approach to time not flowing in the Block Universe where everything exists as a 4D block of all space and all time. In this Universe we just perceive time flowing as we trace out a trajectory.  Interestingly,  it's advocates claim it solves the fine tuning issue but this is challenged by others. I  have one or two books on that too😊.

Regards Andrew 

I think it was one of Carlo Rovelli's books "The Order Of Time" where he mentions the concept of quantised time - I need to be careful as I may be wrong on the source !  And it is speculative, spoken in passing, certainly no evidence as you say Andrew.  Like the notion of Block Time, I find these ideas of time fascinating and also impenetrable for it is difficult, as Vlaiv has pointed out, to lay aside our own very visceral sensation of time.  You are right of course, I very much do favour the pragmatic and practical approach (if I'm honest I'm constrained by it)  - as a creature of engineering I can't shake that off. I know there is a deeper level of description, I can glimpse it fleetingly, happy knowing that it is there    Neil Armstrong put it  better:

"“I am, and ever will be, a white-socks, pocket-protector, nerdy engineer, born under the second law of thermodynamics, steeped in steam tables, in love with free-body diagrams, transformed by Laplace and propelled by compressible flow."

 

Edited March 3, 2023 by saac

[saac]

This is a great thread, we should be paying for this !

Jim 

[ollypenrice]

12 hours ago, vlaiv said:

Anthropic principle is rather simple to understand.

Imagine you win a lottery with very small odds of winning.

You might say - what are the odds of me winning the lottery? How lucky I am? But in reality - someone had to win it and who every won it - can be asking themselves the same question.

One person, how ever unlikely will certainly win the lottery.

Similarly - universe with a set of physical laws - how every unlikely that particular version is - will happen. If it produces us - we have the right to ask, why us? Or rather - why is it the way it is and answer is - because it is random thing.

On the other hand - there is different way of looking at "fine tuning". We can think of it in terms of thermodynamics.

Imagine box of gas with bunch of molecules whizzing around. If gas molecules are equally distributed we call that state - a low entropy state. If all the molecules are in fact in one part of the box - say left half of it - that will be high entropy state.

Now what is important to note is that both of such states are equally possible - any given state has the same probability, but not all the states are equal.

There is particular "quality" of all the molecules being on left side of the box. It is actual physical property of such configuration that makes a distinction between it an other configurations. In this case - it is quality of energy or level of orderliness in the box.

Similarly - while all different configurations of universe are equally probable - not all have equal "quality".

Here we must be careful - in fine tuning we ascribe "significance" to this quality. Significance is totally nonphysical thing and comes from our mind - what we value. On the other hand quality is something that can be mathematically described - in similar way we describe quality of energy. Ability to do more work for same amount of energy means higher quality energy.

Is that better or worse? or is it significant? that is totally up to interpretation, but we must agree that our universe is high quality one - compared to average universe. However - there are higher quality universes in above definition, and the fact that we live in high quality universe, in my view does not warrant ascribing a significance to it in the way of "fine tuning".

Just acknowledging that we live in higher quality universe than average or median universe is enough, me thinks.

I don't understand why people shy away from designed universe in discussions?

I'm not talking religion here. There are many forms of universe by design, and if we don't explore or discuss such idea - it's our loss.

Just earlier this evening - I defended position that mathematics = existence. In sense we could say that existence is generated by mathematics, or rather that two are equivalent. Maybe not design - but certainly is "creationism" - although not in common sense of that term (far from it)

 

I like your lottery argument, which I think is a more elegant presentation of my doubts about the validity of 'fine tuning,' than mine - if I have read you correctly. Someone has to win the lottery but that does not mean that the question,'Why me?' is a valid question unless you can accept the answer, 'Because you were the 1 in a 10,000,000  to 1 chance.'  

I also like your analogy with green light. Green is purely a sensory concept and yet it is meaningful to talk about it because it is a concept we share and which shapes our perception of the world. I've thought for a long time  that time might be like this. So, regarding Andrew's point...

9 hours ago, andrew s said:

 

I am with Einstein that time is what clocks measure and space is what metre sticks measure.  A pragmatic operational approach that I am sure @saac will appreciate.

... I'm happy to agree. Time can exist for the same reason that green can exist. My question would be, 'But what do Strongles measure?'  We don't know because we have never seen a strongle.  However, I think strongles measure  length on a different trajectory through the block universe. Or they may do, if there is a block universe.

To take it further, maybe 'our universe' is one of many others in what we might call a 'block multiverse.'

If the universe we see is the product of the way we see it, then we have the perfect answer to question, 'Why are we here?' and all need for fine tuning (if ever there were any) would evaporate. We would be 'here' because 'here' is what we made when we perceived it.

Olly

Edit:

'This is a great thread, we should be paying for this !

Jim '   Absolutely! All royalties to the OP.  (Now there's a coincidence: O Penrice.  How did that bit of fine tuning come about?)

 

 

Edited March 4, 2023 by ollypenrice

[andrew s]

The other standard time quote is "time is what stops everything happening at once". The root of time is in the observation that things change.

Anyway enough of this pop philosophy back to science.

I have found this paper here which discusses the changes in wavelength associated with Plank scale quantisation as @saac and @vlaiv proposed.

While this one discusses the impact on X-ray and gamma-ray wavefronts.

Both put tight constraints on any proposed foam.

I did find a Sky and Telescope article claiming a detected difference in arrival of soft and hard gamma ray arrival times. However,  it was so full of pop science nonsense I could not bring myself to link to it. Further,  I could not find a related paper. If indeed it was a robust result the researchers would be up for a Nobel prize.

Regards Andrew 

Edited March 4, 2023 by andrew s

[ollypenrice]

13 minutes ago, andrew s said:

The other standard time quote is "time is what stops everything happening at once". The root of time is in the observation that things change.

Anyway enough of this pop philosophy back to science.

I have found this paper here which discusses the changes in wavelength associated with Plank scale quantisation as @saac and @vlaiv proposed.

While this one discusses the impact on X-ray and gamma-ray wavefronts.

Both put tight constraints on any proposed foam.

I did find a Sky and Telescope article claiming a detected difference in arrival of soft and hard gamma ray arrival times. However,  it was so full of pop science nonsense I could not bring myself to link to it. Further,  I could not find a related paper. If indeed it was a robust result the researchers would be up for a Nobel prize.

Regards Andrew 

If time isn't quantized, does that mean we can take physics right back to the beginning? That missing bit during the first 10^-44 sec was really bugging me...

lly

Edited March 4, 2023 by ollypenrice
I originally thought it was 10¨-43 sec. Sorry...

[saac]

16 minutes ago, ollypenrice said:

If time isn't quantized, does that mean we can take physics right back to the beginning? That missing bit during the first 10^-44 sec was really bugging me...

lly

I think that must be where I left my car keys  

Jim 

[andrew s]

19 minutes ago, saac said:

I think that must be where I left my car keys  

Jim 

I think it more likely it's where all socks were initially paired up correctly - before they became fermions. 

Regards Andrew 

[ollypenrice]

20 minutes ago, saac said:

I think that must be where I left my car keys  

Jim 

They're with my specs in that case...

[Ratlet]

13 minutes ago, andrew s said:

I think it more likely it's where all socks were initially paired up correctly - before they became fermions. 

Regards Andrew 

If it wasn't for Pauli we'd all having matching socks.

[Zermelo]

2 hours ago, ollypenrice said:

Green is purely a sensory concept and yet it is meaningful to talk about it because it is a concept we share and which shapes our perception of the world.

We can all agree on the name to give light of a certain frequency, but of course I can never know that the sensation I experience as green is the same as yours, and not instead the one that you experience as red. Some philosophers talk endlessly on that point.

On another point, I think it's likely that our reasoning on fundamental matters like space and time is "tainted" by the niche we inhabit in the universe, in particular our scale. Our brains have evolved to deal with objects of the same scale as us, that behave in certain ways, and that is one reason why QM and relativity seem counter-intuitive to us.

[ollypenrice]

59 minutes ago, Zermelo said:

We can all agree on the name to give light of a certain frequency, but of course I can never know that the sensation I experience as green is the same as yours, and not instead the one that you experience as red. Some philosophers talk endlessly on that point.

While there are purist and technical arguments over whether or not we can know that we experience the same thing when we see a colour, I think these are best seen as arguments about argument rather than about colour perception. I can think of a large number of reasons for concluding that we do experience something at least very similar. Firstly, we soon identify those people who don't share the majority experience and call them colour blind. We can make tests like the Ishihara which strongly suggest a common experience, firstly among the majority and then, to a large extent, among the colour blind as a sub set.  It is also hard to imagine how the visual arts would work without a common experience. And then, given what we know of ocular physiology, we'd have to ask why we would not have a common experience.  This may leave room for debate but, as I say, I think that debate is more an exercise in philosophical method than in anything else. (My father was a perception theorist and dismissed the idea of a non-shared colour perception out of hand. Alas, I can't remember why!)  There are also people who argue that there is no analogue underpinning to perspective as a form of visual representation. They suggest that it is a learned and arbitrary code.  Pah: if you believe that, you'd believe anything! 

Olly

[EarthLife]

Yes we have no means of describing a colour as we each experience it. It's another limitation on our method of communication.