studiot

2 hours ago, Markus Hanke said:

There is no such implication at all - no exchange of information takes place here.

There is no such incompatibility - the combination of SR and QM gives you quantum field theory, which is perfectly well established, and extensively tested too. There are also simpler relativistic generalisations of the QM wave equations, such as the Dirac equation. 

Nicely put. +1

5 hours ago, Sensei said:

C'mon. That's not the speed of light anyone here knows..

etc

Very patient answers if you ask me.

+1

I was waiting till I cooled down to answer to thanks for saving me possible embarrassment.

2 hours ago, ChildOfTheAncientOfDays said:

My claim is that True Lightspeed is the speed limit of reality itself, not just “matter”. General relativity, and time dilation in the locales of black holes prove this fact. Event Horizons are the point at which black holes distort reality and space time enough to slow Light down just enough, which requires a nigh-eternal amount of time for it to be trapped there in the first place, until another nigh-eternal amount of time passes for that Light to be shot out of that black hole again at near Infinite (or rather, nigh-infinite true Lightspeed) for it to escape again.

This whole thing sounds more like something EE Doc Smith might have written in the early 1950s

1 hour ago, martillo said:

As several ones posted, Quantum Mechanics definitely "knocked out" determinism in the universe. You would have to demonstrate the contrary.

I haven't been able to get to this question yet, with all the chaff.

Is prohibition a form of determinism ?

It determines what you can't do after all.

And QM prohibit an infinity of states to particles, waves and all sorts.

Even in Thermodynamics there are prohibitions such as in Caratheodory's version of the second law.

Eigenvalues, eigen states and eigenfunctions are all examples of discriminatory determinism,

as was H Ford's declaration

They can have any color they want so long as it's black.

3 hours ago, martillo said:

Seems I didn't get your point then...

Swansont keeps telling anyone who will listen and many who will not that Science in general and Physics in particular is about models.

Ever hypothesis, law, formula and so on needs testing, calibrating, with guaranteed known data and known results, outcomes etc.

The only such guaranteed data is in the past.

51 minutes ago, Halc said:

Then the robot should predict the indecision and play anything (the game does have a time limit you know), instead of losing by default. You've just pretty much proved Godel's theorem about the halting problem.

Obviously they played this game differently in your playgound.

54 minutes ago, Halc said:

Only some systems exhibit this. You drop successive grains of sand from a fixed point and which way a given grain goes is fairly unpredictable, but the eventual conical hill of sand is very predictable.  Most systems are chaotic, under which small perturbations result in macroscopic differences. The weather, the formation of galaxies from a uniform early state, are examples of this.  Take the state of Earth just after the Theia event. From that state, life is unlikely to form, and if abiogenesis does occur, it will most improbably evolve into anything that would be recognized as a mammal.

This is a ridiculous attempt to contradict by ridicule.

"Only some systems exhibit this."

I said generally, why repeat it ?

"Most systems are chaotic, "

Stated without a shred of proof.

"Take the state of Earth just after the Theia event. From that state, life is unlikely to form, and if abiogenesis does occur, it will most improbably evolve into anything that would be recognized as a mammal."

ditto

But here my comment about the compounding probabilities could apply.

Also you have again omitted any proof of you modifying adjectives.

"You drop successive grains of sand from a fixed point and which way a given grain goes is fairly unpredictable, but the eventual conical hill of sand is very predictable.  "

You actually agreed.

15 minutes ago, martillo said:

Hind-casting is used in predicting clima for instance. Is clima well predicted? I think is not the case. Fails too many times.

How does that invalidate my point ?

42 minutes ago, martillo said:

2 hours ago, studiot said:

I meant to clarify what definition of determinism was in play.

I must point out that the key point of the discussion is about determinism/nondeterminism of the future

Interesting point, but don't we use 'hindcasting' to check/test hypotheses ?

35 minutes ago, lidal said:

Look at the sheer number of papers claiming to disprove special relativity. So do those voices not count? 

Not really since not one of them have achieved their objective.

SR is correct within its domain of applicability.

Some have tried to extend it beyond that and have found that it does not necessarily work beyond its domain of applicability.

37 minutes ago, lidal said:

Even in mainstream, physicists are now openly saying there might be problem with general relativity theory. This was not the case years ago.

This is just plain wrong.

A good history of the century of what he calls "The Battle of General Relativity" was written by Professor Ferriera in 2014.

Even Einstein himself though one thing, then another then yet another during that time.

Lambda, for instance was not originally included.

Einstein added it later then withdrew it.

But today's (Astro)Physicists have found a f=definited use /reason for it.

This is not a simple standard school problem so it would be helpful to tell us the context in which it set.

As said the contact angle at the ceiling must be zero.

So you then need a 'hump' shaped line that flattens out to parallel to the horizontal at both sides. As in Fig A.

Rotating this line will produce a domed hat like an inverted ww1 or ww2 tommie's hat with a dome and a wide flat brim.

This is modelled as in Fig B.

You can reduce this to a one dimensional solution by assuming radial symmetry. This would be expected by the action of surface tension.

This is shown in Fig C.

You have identified the important features of this problem, including the fact that the brim plays a crucial role in maintaining the adhesion since it contains little or no water  (weight) but presents an large surface area to the atmousphere to press against.

As a first estimate I would suggest that surface tension holds the droplet together but does not hold the droplet against gravity.

A more sophisticated model would include the change in surface energy cause by the droplet breaking away, which could be incorporated in the virtual work equation below.

Your force balance can be conveniently solved by the theorem of virtual work, either using a differential virtual vertical displacement or a differential virtual increase in the weight of the drop.

I don't think Young's formula will help you here, but it was a good idea.

The weight of the drop is derivable from the geometry and in particular the surface area.

This is then an extremal (maximisation) problem which could be attacked by good old trial and error or by the calculus of variations if you are seeking an analytical solution.

12 hours ago, Halc said:

Build two machines that play rock paper scissors. They are constructed so that each uses a completely deterministic in algorithm, and each has full access to the state and programming of the other.  If the behavior can be predicted because it is deterministic, then each robot can predict the move of the other and always win. Since the machines can't both win, predictability cannot be had despite the deterministic nature of the situation.

Godel did a simpler proof, but that one is a bit more on topic.

Or they will never complete a game.

12 hours ago, Halc said:

I don't understand these comments or the relevancy to my comments to which they replied. Perhaps you don't grok what I said. I admit the lack of elegance in my conveying it.

17 hours ago, Halc said:

On 11/7/2023 at 1:02 PM, studiot said:

There is a cause and effect connection to determinism so if we can consider the very last cause before the effect Joigus comment of how far back can we go along the chain of cause and effect is pertinent.

If you can go back even a short time, then that prior state must be fully determined by the state shortly prior to that, and so on...

Hence if we can go back a little and retain determinism, then we can go back all the way to the beginning.  Of course there's no evidence of this short term determinism. For one, it presumes a meaningful state of a system, which is a counterfactual, and few interpretations of QM support counterfactuals.

I grokked that you didn't grok what I said so I will rephrase it.

I meant to clarify what definition of determinism was in play.

This asked whether determinism refers to a single event (eg your robots playing RPS) or goes back some indeterminate distance down a causal chain of events.

FYI my mathematical comment observes the fact that a chain of probabilities (eg a chain of event each with a probability) does not in general converge to zero but to a definite value and is therefore deterministic, even though we do not know the individual probabilities involved.
Probabilities trees are even more complicated.

43 minutes ago, lidal said:

My point is that it is impossible to bring unification in physics without destroying much of modern physics.   

 

If that is really your point, why didn't you say so in the first place (first post ?)

4 hours ago, Anirudh Dabas said:

  

I encountered a situation where I was unexpectedly blacklisted by the site, receiving an error message stating, "*** Forbidden. Sender blacklisted.***" This unfortunate occurrence hindered my involvement in the exchanges that I've come to value on this thread.

Anyways,

I would like to offer a different perspective on the relationship between physical processes and mental phenomena, diverging from the notion that mental phenomena are solely supervening on physical and biochemical processes without being directly driven by them.

While I appreciate the distinction drawn between physical processes and mental phenomena, the assertion that mental phenomena do not directly arise from physical and biochemical processes overlooks the intricate connection between our physiology and our cognitive experiences.

The prevailing scientific understanding underscores the significant role of physical and biochemical processes in shaping our thoughts, decisions, and conscious experiences. Neuroscientific research consistently indicates that mental activities, thoughts, and decisions correspond to specific neural activities and biochemical interactions within the brain.

Contrary to the analogy of a book, where its essence is distinct from its physical existence, in the case of conscious experiences and decision-making, the essence is intricately linked to the physical processes occurring in our nervous system. These physical processes are the very substrate from which mental phenomena emerge, shaping our values, perceptions, and decisions.

Acknowledging the complexity of conscious experiences does not necessitate a departure from the understanding that our mental phenomena are fundamentally driven by the underlying physical and biochemical processes in our nervous system. The emergent nature of consciousness does not imply a detachment from its physical basis; rather, it underscores the interdependence and intimate connection between the two.

Unlike a book where its essence, like its meaning, can be detached from its physical form, in our conscious experiences, the essence seems to be inseparable from the physical activities in our nervous system. It's not just a case of the mind being a separate entity from our physical selves; instead, our thoughts and decisions seem to emerge from the very workings of our brains.

It's not about downplaying the significance of our mental experiences, but rather recognizing that the core of our decision-making and consciousness is deeply connected to the biological and neural processes in our bodies.

The idea here isn't to dismiss the meaningful content of our thoughts or experiences, but to highlight that these experiences are deeply intertwined with the biochemical and neural activities in our brains.

 

The idea that our consciousness and the stories we tell ourselves about our decisions come after the fact is pretty intriguing. It got me thinking about how we connect with our actions and why we sometimes identify with them, and sometimes not so much.

Think about it: when we act in line with our own wishes and motivations, it feels like we own those actions. But when something happens by chance, like tripping over a stone, it doesn't quite fit the bill as an action. It lacks that personal intention behind it, right?

It's interesting to consider that we often identify with actions that align with our intentions and motivations. When our actions are in line with our own impulses or desires, there's a strong sense of ownership and recognition. Conversely, instances where actions are purely accidental, lacking any intention, or forced by external influences can create a disconnection from identifying those actions as our own.

This brings into focus the distinction between intentional acts, chance events, and coerced actions. Stumbling over a stone, resulting in an unintentional fall, doesn't fit the mold of an action as it lacks intent. Similarly, when our actions are coerced or directed by external forces, they might not resonate with our personal motivations, leading to a lack of identification.

These reflections challenge the notion of what constitutes an action and how our narratives of identification are intricately linked with our intentions and motivations. It prompts us to examine the role of intentionality and personal agency in shaping our narratives and our sense of self.

The idea that our feeling of consciousness and the freedom to choose are just stories we tell ourselves after we've already made a decision is mind-boggling. It challenges the way we usually think about our actions and the role of our conscious minds in making choices.We often believe that we're in control, consciously making decisions as we go. But this take suggests that our brains might kick things into gear before we're even aware of it, almost like our decisions are made before we realize we've made them...It's like our conscious mind is playing catch-up, creating this narrative to explain what we've already done. Really does put a question mark on how much we truly control our choices and how much is shaped by processes we aren't even aware of.However, it's not all cut and dry. Even if our consciousness pieces the story together after the fact, it doesn't mean it's not important. It's like it might still have a say in how we interpret our actions, even if it doesn't call the shots on the decisions themselves.

This whole concept, unfortunately, pushes us to rethink the age-old idea of free will and what it means to be in control of our actions. 

The idea that our sense of consciousness and freedom to choose is merely a narrative constructed after a decision has been made challenges the traditional notion of consciousness driving our choices. While I somewhat agree, I believe it's essential to maintain a balanced perspective. It's possible that our consciousness and sense of agency, while influenced by unconscious processes, still play a vital role in our decision-making.

This concept raises intriguing questions about the nature of free will, prompting us to consider the interplay between our conscious experiences and the unconscious processes shaping our decisions. It poses a challenge in understanding the intricate relationship between our perceived freedom and the underlying subconscious mechanisms that influence our actions. In essence, while our consciousness might indeed construct a narrative post-decision, the full scope and influence of conscious awareness on our choices invites a deeper examination of the complexities of human decision-making and the nature of free will.

I do, however, would like for somebody to address this.

You put a lot of effort into this reply to only two participants.

So how about you reply to some of the many other participants ?

Incidentally I thought this a good point

4 hours ago, Anirudh Dabas said:

Think about it: when we act in line with our own wishes and motivations, it feels like we own those actions. But when something happens by chance, like tripping over a stone,

Though what do you mean about it not being an action ?

Also have you heard of reflexes and involuntary actions or the many action we carry out all the time without thinking about them at all, such as breathing and walking (can you normally feel the ground when you walk?)

3 hours ago, Halc said:

Don't confuse determinism with predictability. One can have a nice classical fully determined universe (such a Newton might have envisioned) and it would still not be predictable. It's pretty easy to show that.

Well why not show it then ?

3 hours ago, Halc said:

Hence if we can go back a little and retain determinism, then we can go back all the way to the beginning. 

Re this second quote and 'predictability v determinism'.

The mathematics of continued products would disagree with you.

9 hours ago, joigus said:

The words "elbow room" kind of gave it away.

There are two figures of speech (that I know of) involving elbows in the English language. Both are robust but quite inoffensive.

Howevr the German' Lebensraum' has connotations that might offend some members.

So I am trying to ignore it.

24 minutes ago, Eise said:

Is there a causal relationship between the pixels of a monitor and the text you are reading on that monitor?

Interesting question +1

This is also an interesting question +1

28 minutes ago, iNow said:

I’ll ask now for a 3rd time this question you’ve already evaded twice: If not physical and biochemical processes, what other variable do you believe leads to cognition and mentation?

I would say the mathematics of continued products.

12 minutes ago, exchemist said:

This does not seem to address my point. 

I suppose one advantage of the particles clinging to the glass surface would be that they all stay in one plane and thus can be easily kept in focus when examined with the microscope.  I would have thought their motion might be inhibited somewhat by contact with the glass, but apparently it is not enough to prevent the demonstration from working. I suppose if they are hydrophobic they will probably not be strongly stuck to the glass either, since that too is a polar medium. 

Perhaps what I need to do is find some detailed instructions for how to set this demonstration up, and see what they say about it.  

I look forward to your report.

Please note I am not expert in this  -  it was only a memory from long ago so I was gratified to find out that my memory had not failed me.

So I am having to do some fast thinking on the hoof to answer your excellent questions and if you come up with something new I would be glad to hear about it.

30 minutes ago, joigus said:

One thing is physical determinism, and quite a different thing is behavioural, psicological --or what may have you-- determinism.

Ie. Suppose some kind of physical determinism has been established and we all agree on it being the basis for the physical world.

There would still be a long way to go in order to prove or convince anybody that this has any bearing on the question of free will, as @Eise has argued somewhere else, if I'm not mistaken.

Those are two different things.

How does this affect the issue raised by the thread ?

9 minutes ago, exchemist said:

Yeah but I'm not questioning whether or not it is used to show Brownian motion. Evidently it is. It is just that my previous understanding of the demonstration, that the particles were in the body of the liquid and being buffeted in all directions by water molecules, can't be correct. They must be clinging to the glass and sliding around in 2 dimensions only.  

Water has very strong Van Der Waals forces.

Hydrophobic particles are not influenced by these.

That leaves momentum/KE exchange for the buffeting.

On a slightly different tack here is an interesting modern pdf about this issue, from a fractal invariant maths and a neuroscience point of view, from Oxford university.

Quote

https://academic.oup.com/cercor/article/33/8/4574/6713293

 

A third factor hindering a mechanistic understanding of brain function is rooted in our failure to construct computational models that reproduce the principles employed by the brain

10 hours ago, Killtech said:

the constantly or isotropy of the speed of light always refers to the constant c as it appears in the Maxwell equations for vacuum and it is strictly constant by postulate. the speed of light in a medium is not - and most text name it as such so not to mistake it with the (vacuum) speed of light.

Due to its specific context to the vacuum Maxwell equations, the constancy or isotropy of it in all frames almost uniquely fixes the form of that equation in every frame to the same shape (you could argue that hypothetically the ratio between ϵ0 and μ0 could change in the equations... but no), which practically implies it has to be invariant. In reverse, the invariance assures that all constants that appear in the equation stay the same. So for constancy of c and invariance of vacuum Maxwell are almost equivalent in SR.

c is different from a spring constant which definition isn't that strict, such that it may change with rising temperatures.

More generally in order to be able to speak about constancy, a quantity must be represented as a value or some other mathematical structure for which such a relation is even defined. objects in reality aren't made out of number and it is only measurement that associates them with numbers. Not all measurement methods are per se guaranteed to be consistent to each other, i.e. distances can be measured by in units of a rod or the time light in vacuum takes to travel that distance, or they could be just given as a difference of coordinate - one may find two distances to have same length with one method but mismatch with another. 

physical frameworks usually define everything clearly enough, including the valid methods of measurement leaving no ambiguity and therefore within such a framework it is clear if a physical entity is a constant or not. what defines such a framework is not just the laws of physics, but also a lot of technical definitions and conventions. Therefore, it may be a question of representation rather then physics if a quantity is constant or not. 

Basically I agree with pretty well all you have said here.

I would just stress that there are many types of invariants (see my answer to StringJunky below)  invariants are not functions, there is no' invariant function', as there is a 'constant function'  in maths.

Invariants are a property of certain types of functions or transformations.

16 hours ago, StringJunky said:

Invariance is when one calculates, say a transformation, and the observed parameter (constant) remains unchanged. Is that correct?

Yes

Invariants are a property of certain types of functions or transformations.

As such they are the foundation of the modern way that relativity is viewed.

But not all invariants work the same way.

For instance the fractal invariant or the scale invariant is an invariant of geometry that does not related to a coordinate frame like relativity.

There is an interesting modern view of fractal invariants in Neural Nets and the Brain from Oxford University (in pdf) that I am about to post in that long runningargument over artificial consciousness.

https://academic.oup.com/cercor/article/33/8/4574/6713293

2 hours ago, exchemist said:

Thanks - something I did not know. But that raises a question in my mind about its use to demonstrate Brownian motion. My understanding is this is done in a water droplet on a microscope slide. But if the grains are hydrophobic, then presumably they will not be in the bulk liquid but clinging to the glass of the slide and being nudged this way and that, along the surface of the glass. Is that your understanding?  Or is a surfactant used to to get them to disperse into the water? 

I checked an my memory of long ago was correct.

I thought brownian motion was where I had first heard of lycopodium powder.

Quote

Lycopodium powder - Wikipedia

Because of the very small size of its particles, lycopodium powder can be used to demonstrate Brownian motion. A microscope slide, with or without a well, is prepared with a droplet of water, and a fine dusting of lycopodium powder is applied.

Quote

https://www.vedantu.com/question-answer/what-is-the-role-of-lycopodium-powder-class-12-chemistry-cbse-60b06e074d283232b04d68

 

What is lycopodium powder used for in physics?

 

 

The powder has long been used in physics experiments to explain Brownian motion and other phenomena. During the experiment to estimate the molecular size of oleic acid, lycopodium material coats the entire water surface. Since oleic acid does not dissolve in water, a drop of the solution spreads on the water surface.

5 hours ago, swansont said:

The answer referred to observers in different frames. That’s an issue of invariance. Being constant was not mentioned. Being invariant does not imply that something is constant (mass, for example)

I didn't say it was and I agree that one of the main uses of the term invariant is the comparison of something between different coordinate systems or frames.

I tried to avoid some of the more esoteric uses and offer a solid physical one.

The physics of tha lamp  oscillation is form invariant between the frames.

But that form include a coefficient which is constant, but that constant has a different value is different in every frame, so the constant itself is not invariant.

I was also trying not to point the finger at individuals but since you are commenting on Markus, I think he was to enthusiastic when he wrote this.

On 11/6/2023 at 7:40 AM, Markus Hanke said:

Constancy means that c always has the same value under all circumstances - which it evidently does not, since its value depends on the permittivity and permeability of the underlying medium. For example, c is different in glass than in vacuum. This is a direct result of Maxwell’s equations.

all circumstance ?

No any more than the spring constant has the same value under all circunstances.

It too is constant under a ( more limited) specific set of circumnstances in that it is constant over a range of extensions of the spring.

Anyway if you don't like that example try analysing the oft quoted 'constant AC voltage'.

Or perhaps the example I gave before, which has nothing to do with coordinate systems or frames.

My freezer keeps a constant temperature, but this temperature is not invariant as I am at liberty to turn the temperature maintained up or down.

Or a final one

Most of physics can be described by differential equations.

We obtain 'solutions' to these DEs by integrating them.

But integration includes an arbitrary constant of intgration, which is not therefore invariant.

Of course we can eliminate the constant if we work by difference as in the definite integral or in the case of relativity coordinate differences.

These words have a lot of work to do.

2 hours ago, exchemist said:

Why do you say lycopodium powder grains are hydrophobic?  

https://www.facebook.com/watch/?v=323855678960326

Quote

Lycopodium powder is the spores from a club moss. They are extremely hydrophobic so create a barrier between the fingers and water 

1 hour ago, swansont said:

Differing between the train and the observer is an issue of invariance. Being a constant was not addressed.

I'm sorry I don't follow.

As the lamp is osscillating up and down its travel distance lies at right angles to its motion as part of the train so it is unaffected by relativity.

But as part of the train its receeding motion affects the observer's perception of the period of the oscillation in accordance with relativity.

So its period will appear to increase (as Markus says).

But its period depends on the spring constant

Quote

Mass on a spring - Where a mass m attached to a spring with spring constant k, will oscillate with a period (T). Described by: T = 2π√(m/k).

 

University of Birmingham.

Since the period increases k must decrease.

So it is a different spring constant.

17 minutes ago, sethoflagos said:

Given a free neutron in whatever initial boundary conditions you care to set, in what sense could its instant of decay into a proton and W^- be understood to be '(pre)determined' prior to the actual event?

If there is none then it would seem to me that dterminism in any real sense is dead on its feet. Otherwise we would appear to have the mother of all hidden variables theories and I'd be interested to hear how this squares with the 2nd Law (where's all the information stored?)

Perhaps I'm missing something (yet again).

Another good comment and viewpoint.

I think that the fact that it will decay to a proton  etc and not a raspberry pie is determined, but that when it will happen is not.

So with all that latitude we should all be more careful how we use the word in technical discussions.

13 minutes ago, Eise said:

Does one 'fix' the temperature with a thermometer? 

The only way I would use that would be to mean to establish a base temperature to measure from.

Otherwise knows as 'benchmarking' in modern parlance.

There is no cause and effect relationship in play.

Keep the questions coming because they are showing good things and just how deceptively complex the subject whicha t first sight seems to simple and clear cut, really is.

Here is a counter example to (1)

Lycopodium powder.

This was once used to demonstrate brownian motion, where the hydrophobic powder particles definitely do not clump together.