What's wrong with Physics?

[Macavity]

I wasn't familiar with the Youtube (recommended) Videos of Dr. Sabine Hossenfelder.
I find myself agreeing with *some* of this. But, for a lay audience, is it "Careless Talk"? 😅

After viewing a couple, my own feelings are, in words of a (non-Physicist) "Quora Pundit":
... “She likes pointing out problems we already know, without providing new solutions”?   😸
I sense this is a pathology of so many of Youtube's self-defined "renegade" whatevers?!?

But "AIBU" (Am I being unreasonable!) as they say on Mumsnet? Can I persuade anyone
to LOVE Particle Physicists. I have *always* spoken very HIGHLY of Amateur Astronomers!
(Modest claims to have been both). Or should I start looking for the Nearest Clifftop? 🤣
 

Edited August 4, 2022 by Macavity

[DaveS]

I'm subscribed to her channel, so I'll have a look this evening. From her other videos she looks to have become rather disenchanted with theoretical physics, and physicists.

Her book "Lost In Maths" says a lot more.

[andrew s]

Apart from the detection of the Higgs boson and gravitational waves, which were expected,  there has been no new clear cut experimental results for theorists to get their teeth into other than dark matter and dark energy.

The failure to find dark matter particles leaving both dark energy and matter hanging theoretically and the continuing inability to reconcile general relativity and QFT has left physics with two very good theories and no clear path forward. 

We need some genuinely novel experimental results to lead theorists out of their mathematics and back to reality (whatever that is).

Regards Andrew 

[Macavity]

17 minutes ago, andrew s said:

We need some genuinely novel experimental results to lead theorists out of their mathematics and back to reality (whatever that is).

Maybe so. But how can experimentalists "lead" via novel results...  without these "costly" upgrades.
There may indeed be "nothing to see"? In part, I envy Astronomers... They have their JWST pictures!
Not really sure how (Particle) Physicists (A bit of a generic term - like ALL wo/men!) go from here? 🧐

But I DO THINK that "Physicists" have long reflected on "is it worth it" etc., despite Youtube critics. 🙃
 

Edited August 4, 2022 by Macavity

[vlaiv]

Well, I've come to a conclusion that something is seriously wrong with physics.

Everything about physics tells us that "free will" is all but illusion, and I'd be fine with that - except there are some fundamental things that can't be explained by it being merely an illusion.

I'll list 3 types of things in ascending order of "weight".

First would be "Beerman's argument" that I formulated like this:

"I decide to go out for a beer with some of my friends. We set a time and we end up on that beer together".

Now, I find that it is very unlikely that two would match - my idea of going out for a beer and actually going out for a beer at agreed time. It only gets "worse" - with more people involved (less odds). It is not impossible in deterministic / stochastic universe for this to happen as we know of mathematical structures with large amount of self similarity (fractals).

Similarly - idea and actual drinking of the beer could be parts of self similar set - one realized in brain - other in world.

But I find that to be very unlikely.

Second argument would be - judiciary system and for example upbringing / education

Both are created under impression that punishment / reward will have an effect on our decision making. We teach our children how to behave and we "correct" behavior of adults when not in line with what is expected.

Now, if free will is an illusion - I'd be happy to accept that either of two mentioned things is nonsensical - no point in doing as physical system will evolve according to its own rules and punishing man for a crime is as efficient as punishing a tree for falling onto a car and destroying property.

Third argument is probably the strongest one. We have feelings.

Why do we feel hungry? Why do we feel pain? Why do we feel love?

In deterministic universe - these mechanisms absolutely make no sense. Why do I need to feel hungry when I'm about to eat because physical system will evolve in that way according to its own rules (no really other option as everything is deterministic).

In stochastic system - well things will evolve in random manner, again - I don't see much room for being hungry or in love.

I think it would be wise to try to understand the way we thing about natural world in terms of these phenomena that we often "push aside" to other sciences.

[900SL]

Her principle argument is that research funding is channelled into Megabucks projects like the LHC and that the field is awash with theory that is arguably incorrect or untestable.

Vested interests looking for big budgets and empire building. I think she feels the money could be better spent.

I like her stance. The world needs bubble bursters and Emperor's New Clothes shout outs

[Macavity]

24 minutes ago, 900SL said:

Her principle argument is that research funding is channelled into Megabucks projects like the LHC and that the field is awash with theory that is arguably incorrect or untestable. Vested interests looking for big budgets and empire building. I think she feels the money could be better spent.I like her stance. The world needs bubble bursters and Emperor's New Clothes shout outs

But maybe, the real problem is with "Human Nature", rather than the... "Physicists"?
A lot of "science critics" forget their own "workplace experience"? There will always
be the "Empire Builders" .... "Credit Stealers"... the "Lazy Gits"... "Sociopaths"(!) etc. 😑

Hey, I'd still rather *argue* with a common-or-garden "Scientist" (mostly)! lol
Social Media does seems to have a lot of experts...  in loaded language etc. 😏

Edited August 4, 2022 by Macavity

[iantaylor2uk]

Just in reply to vlaiv, it is well known, in both physics and maths, that there are many complex systems which are completely deterministic, but essentially unpredictable (weather systems are one example) and it is very likely the human brain is another example. So free will could actually just be the chaos of a complex deterministic system!

[vlaiv]

4 minutes ago, iantaylor2uk said:

Just in reply to vlaiv, it is well known, in both physics and maths, that there are many complex systems which are completely deterministic, but essentially unpredictable (weather systems are one example) and it is very likely the human brain is another example. So free will could actually just be the chaos of a complex deterministic system!

Deterministic system is - well deterministic and hence predictable 100%.

We are not talking here about chaos theory - fact that very small change in initial conditions will lead to large differences after evolution of system for some time.

I'm trying to point out that our understanding of physics on fundamental level can't produce phenomena that we experience in every day life (or it is very very unlikely).

If what we perceive free will as being product of deterministic system - no matter how complex, then future state of system is simply function of initial conditions and transition function (physics laws).

In such system there is simply no need to feel hungry in order to eat. Eating will happen or not - based on initial system state and transition function.

All our physics laws are formulated in "initial conditions + transition function" fashion. I think that is problem - that is what is wrong with physics.

 

[Macavity]

GOSH! I wish I wasn't such a "thicko" re. this stuff! But (sincere) KUDOS anyway! 😅
Perhaps, there is no point "arguing with a theorist"?!? (Sabine Hossenfelder?)
Sometimes, I don't know... Is there hope for "mere mortals"? 🙂

[900SL]

No. The human race is an evolutionary branch likely destined to self destruct. Monkeys with Megatons.

 

All I can say is that hydrogen has a warped sense of humour

[iantaylor2uk]

48 minutes ago, vlaiv said:

Deterministic system is - well deterministic and hence predictable 100%.

We are not talking here about chaos theory - fact that very small change in initial conditions will lead to large differences after evolution of system for some time.

I'm trying to point out that our understanding of physics on fundamental level can't produce phenomena that we experience in every day life (or it is very very unlikely).

If what we perceive free will as being product of deterministic system - no matter how complex, then future state of system is simply function of initial conditions and transition function (physics laws).

In such system there is simply no need to feel hungry in order to eat. Eating will happen or not - based on initial system state and transition function.

All our physics laws are formulated in "initial conditions + transition function" fashion. I think that is problem - that is what is wrong with physics.

 

The work of Mandelbrot & others has shown that in nature, complex systems very simply arise from simple, often scale-free rules. Although they may, in theory, be deterministic, they are essentially unpredictable. Space-time most likely arises from simple rules, which we don't yet know. However we do know from quantum mechanics that the initial conditions will never be known perfectly, so space-time will most likely be an example of a deterministic unpredictable system, and since we, and our brains, are all within space-time, this will also apply to us. 

[andrew s]

1 hour ago, vlaiv said:

All our physics laws are formulated in "initial conditions + transition function" fashion. I think that is problem - that is what is wrong with physics.

Not if you believe in the "block" Universe.  It all exists but we just experience it a moment at a time.

Of course Physics doesn't claim to be correct just good at predicting things in the scope of its theories.  

To be honest I don't understand your initial post on this. 

However,  on determinism there are never exact initial conditions due to QM and even if there were the large number of degrees of freedom means any pretense at prediction is all but impossible.

Take a simple example. You can't even in principle say if a photon from a star will hit a particular spot on your CCD detector only the probability of it happening. Once it has arrived the arrival time of the next is only statistically predictable as is the total  number of hits in a given time.

There are some 86 billion neurons in the brain and many more interconnects. We have no physical theory of it's emergent properties e.g. consciousness.

Regards Andrew 

Edited August 4, 2022 by andrew s

[saac]

Do these existential crisis only afflict Physics, I've never seen such applied to Chemistry or Biology!  What is it about Physics that seems to attract such statements, is it driven by a particular social media influence?   Chemistry in crisis - yeah ok, move on  

Jim 

[Macavity]

6 minutes ago, saac said:

Do these existential crisis only afflict Physics, I've never seen such applied to Chemistry or Biology!  What is it about Physics that seems to attract such statements, is it driven by a particular social media influence?   Chemistry in crisis - yeah ok, move on

Brilliant, Jim! Something I had (unconsciously) begun to wonder... 😅
++1 for the rest too! lol

Edited August 4, 2022 by Macavity

[Earl]

2 hours ago, vlaiv said:

Well, I've come to a conclusion that something is seriously wrong with physics.

Everything about physics tells us that "free will" is all but illusion, and I'd be fine with that - except there are some fundamental things that can't be explained by it being merely an illusion.

I'll list 3 types of things in ascending order of "weight".

First would be "Beerman's argument" that I formulated like this:

"I decide to go out for a beer with some of my friends. We set a time and we end up on that beer together".

Now, I find that it is very unlikely that two would match - my idea of going out for a beer and actually going out for a beer at agreed time. It only gets "worse" - with more people involved (less odds). It is not impossible in deterministic / stochastic universe for this to happen as we know of mathematical structures with large amount of self similarity (fractals).

Similarly - idea and actual drinking of the beer could be parts of self similar set - one realized in brain - other in world.

But I find that to be very unlikely.

Second argument would be - judiciary system and for example upbringing / education

Both are created under impression that punishment / reward will have an effect on our decision making. We teach our children how to behave and we "correct" behavior of adults when not in line with what is expected.

Now, if free will is an illusion - I'd be happy to accept that either of two mentioned things is nonsensical - no point in doing as physical system will evolve according to its own rules and punishing man for a crime is as efficient as punishing a tree for falling onto a car and destroying property.

Third argument is probably the strongest one. We have feelings.

Why do we feel hungry? Why do we feel pain? Why do we feel love?

In deterministic universe - these mechanisms absolutely make no sense. Why do I need to feel hungry when I'm about to eat because physical system will evolve in that way according to its own rules (no really other option as everything is deterministic).

In stochastic system - well things will evolve in random manner, again - I don't see much room for being hungry or in love.

I think it would be wise to try to understand the way we thing about natural world in terms of these phenomena that we often "push aside" to other sciences.

Trying to link Physics to Feelings and outcomes opens a Pandora's box

[vlaiv]

54 minutes ago, iantaylor2uk said:

Although they may, in theory, be deterministic, they are essentially unpredictable.

This statement does not make sense.

If something is deterministic - then it is predictable. Can we predict it with 100% certainty? That really depends if:

1) we can determine initial conditions with sufficient precision

2) we can determine physical laws with sufficient precision

Something being deterministic does not depend on our ability to predict its course (law of gravity or electromagnetism worked the same at the time when it was mystery to us - it did not change because we managed to write down laws for them).

44 minutes ago, andrew s said:

Of course Physics doesn't claim to be correct just good at predicting things in the scope of its theories.  

To be honest I don't understand your initial post on this. 

Scope of physics is a bit more then just being good enough approximation.

It also aims to describe the world around us and help us get deeper insight in how things work. That is one of the reasons why we want to, for example, interpret QM instead of just shutting up and calculating ...

Sometimes it is very beneficial to ask - what is it that equations are in fact telling us.

I'm simply going from very basic and using induction (maybe this is where there is an error in my thinking / understanding). We formulate all laws of physics as initial condition + transition function.

Even Quantum mechanics  does that even if it does not appear so with probabilities included. Our model assumes that we have initial state and we have evolution of wave function which produces wave function and some future time. Is there randomness in how that function evolves? No, not really - it is deterministic in nature.

51 minutes ago, andrew s said:

There are some 86 billion neurons in the brain and many more interconnects. We have no physical theory of it's emergent properties e.g. consciousness.

We can look at this from two different vantage points.

1) There is nothing in inherent determinism of universe (if it really behaves that way) to prevent emergent properties. That is not paradox / contradiction. We might be just "watching a movie" unfold in front of our eyes because we are emergent awareness from very large number of neurons - that just simply act out according to physics laws given initial conditions

2) Maybe we don't have physical theory because we are stuck with current paradigm - but instead of paying attention to signs that it might be flawed - we press on?

 

[vlaiv]

9 minutes ago, Earl said:

Trying to link Physics to Feelings and outcomes opens a Pandora's box

No, not really.

It is phenomena like any other around us. We do have them, we do have at least basic understanding of what hunger is.

It is something that is evolved with complexity. I doubt that plants have hunger / urge, but dogs and cats certainly do seem to have it.

Imagine a robot that is programmed according to set of rules - like, "when battery is low, find nice sunny spot and deploy your solar panel".

Will "robot feeling hungry" make it more likely to do that if it already has a rule for it?

Under what circumstances can you see "robot deciding" not to deploy solar panel and instead perform another task. Only if it is programmed to do so.

We can add randomness in all of that (random component in rules) - and I still don't see reason for feeling hungry.

[saac]

If we are watching a movie for heaven's sake do not fast forward to the end - I want to spend my time enjoying it  

Jim

[iantaylor2uk]

The whole point is that quantum mechanics says that the initial conditions can never be known exactly which is precisely why deterministic systems can be unpredictable. I suggest you look up references that describe iterations of the logistic equation and/or Julia sets in maths.

[vlaiv]

Just now, iantaylor2uk said:

The whole point is that quantum mechanics says that the initial conditions can never be known exactly which is precisely why deterministic systems can be unpredictable. I suggest you look up references that describe iterations of the logistic equation and/or Julia sets in maths.

where does it say that initial conditions are fundamentally indeterminable?

Take for example following:

"If we prepare electron in spin up configuration .... bunch of calculations follow" - in our calculations we start from well defined initial conditions.

Then we do experiment like this:

Pass electrons thru oriented magnetic field and we select those with spin up to test our prediction given by above.

Only thing that is questionable in the whole process is our ability to measure precisely (and the fact that we can't measure some things at the same time - but that does not mean that wavefunction itself is not in exact state).

[Synchronicity]

2 hours ago, vlaiv said:

Deterministic system is - well deterministic and hence predictable 100%.

We are not talking here about chaos theory - fact that very small change in initial conditions will lead to large differences after evolution of system for some time.

I'm trying to point out that our understanding of physics on fundamental level can't produce phenomena that we experience in every day life (or it is very very unlikely).

If what we perceive free will as being product of deterministic system - no matter how complex, then future state of system is simply function of initial conditions and transition function (physics laws).

In such system there is simply no need to feel hungry in order to eat. Eating will happen or not - based on initial system state and transition function.

All our physics laws are formulated in "initial conditions + transition function" fashion. I think that is problem - that is what is wrong with physics.

 

I don't think it's feasible to ever answer whether there is any determinism at play in any situation because we don't have all the information.   All that you mention might be 100% predictable, just not with our knowledge or scientific/computational capability.  After all, we can't model particles or forces we don't yet understand - or even know about.

Incidentally, your "Beerman's argument" doesn't illustrate determinism or free will, it illustrates cause and effect.  Someone suggests a pub visit, others who hadn't planned to go to the pub decide to go or not.  If a sufficient number agree to go you reach critical mass which then attracts more people.  None of that happens without someone suggesting going to the pub 🙂

Michael

[Macavity]

Having worked with FUN German Physicist teams (and French ones too)
Sabine doesn't seem to be a "whole bundle of laughs"? lol. But, Hey! 😅

These days, SCIENCE has a lot of trouble finding funds to merely exist?
I find myself reluctant to support these... "friendly fire" things? Whether
the protagonist is "anti-science" (I rather doubt that!) seems irrelevant.
Sadly, a lot of the FANS / SUBSCRIBERS to such channels seem to be. 😔

I feel Science need all the support it can get.
If I can "LOVE" Brian Cox, so should you! 🤣

[andrew s]

2 hours ago, vlaiv said:

If something is deterministic - then it is predictable. Can we predict it with 100% certainty? That really depends if:

1) we can determine initial conditions with sufficient precision

2) we can determine physical laws with sufficient precision

But for large system we can't  meet your conditions that's why all physical theories revert to course graining. That's what I was pointing out.

 

2 hours ago, vlaiv said:

We formulate all laws of physics as initial condition + transition function.

We can do it that way but don't have to hence Largrangian and Hamiltonian mechanics and principle of least action.

In QM  you prepare a state (spin up) if you measure it for up or down you get spin up 100% but if you measure at a different angle you can only predict probabilities of less than 100%. In this sense it is not deterministic. 

Regards Andrew 

PS not all systems have a wave function (electron spin is one) and you have use matrix mechanics which has no concept of deterministic evolution. 

Edited August 4, 2022 by andrew s

[vlaiv]

19 minutes ago, andrew s said:

In QM  you prepare a state (spin up) if you measure it for up or down you get spin up 100% but if you measure at a different angle you can only predict probabilities of less than 100%. In this sense it is not deterministic. 

It is deterministic in the state of the system - but not measurement.

We are used to thinking in terms that state of the system is the complete set of measurements - but QM thought us differently - there is state of the system that is unique and describable but not necessarily measurable.

I must admin that here we have to subscribe to particular interpretation of quantum mechanics.

I tend to subscribe to following:

- wave function is element of reality (not merely tool for calculation) - or rather QM fields are fundamental building blocks

- there is no spontaneous collapse of wave function, lack of superposition can be explained by decoherence

- there is universal wavefunction

This all sounds very similar to many worlds interpretation - but I'm not 100% on board with that, so don't just assume that I subscribe to that.

With above - we have deterministic evolution of wave function. No probabilities involved at all. It does not however explain why do we get one particular measurement over others (and again, I don't think that many worlds is the answer - but something close to it).