[Bored chemist]

Surely the term "random" means essentially "lawless"?

So, it's not just physics you don't understand.
You can't grasp English either...

[Bored chemist]

Einstein famously complained about this a century ago. Has his complaint been convincingly answered?

Yes, it has.
And the answer is "just because you don't like it won't stop the universe acting that way.".

[evan_au]

Much the same as rolling a pair of dice.  You cannot predict what number the dice will add up to, at the instant they come to rest...
How can there be any "laws" governing "randomness"?

There are laws of statistics.

If you roll a pair of dice, the total score can be anywhere from 2 (snake eyes) up to 12 (double 6).
- If you roll the die once, you could get any of these
- But if you roll it many times (eg 100 times, or more) you are almost certain to see a 7 more than a 2 or 12
- This is because out of the 36 possible combinations of two dice:
- Only 1 combination gives a 2 = 1+1
- Only 1 combination gives a 12 = 6+6
- But 6 combinations gives a 7 = 6+1=5+2=4+3=3+4=2+5=1+6
- So a 7 is six times more likely than 2 or 12
- So you can predict the outcome of rolling a pair of dice, if you are predicting the results over many experiments.

Just like you can predict the bright and dark bands in the 2-slit experiment, if you run the test over very many photons.

[Janus]

Much the same as rolling a pair of dice.  You cannot predict what number the dice will add up to, at the instant they come to rest...
How can there be any "laws" governing "randomness"?

There are laws of statistics.

If you roll a pair of dice, the total score can be anywhere from 2 (snake eyes) up to 12 (double 6).
- If you roll the die once, you could get any of these
- But if you roll it many times (eg 100 times, or more) you are almost certain to see a 7 more than a 2 or 12
- This is because out of the 36 possible combinations of two dice:
- Only 1 combination gives a 2 = 1+1
- Only 1 combination gives a 12 = 6+6
- But 6 combinations gives a 7 = 6+1=5+2=4+3=3+4=2+5=1+6
- So a 7 is six times more likely than 2 or 12
- So you can predict the outcome of rolling a pair of dice, if you are predicting the results over many experiments.

Just like you can predict the bright and dark bands in the 2-slit experiment, if you run the test over very many photons.

Or another example that deals with atoms:  There is no way to tell when any given atom of Radon 222 will decay. It could be in the next sec or a thousand years from now.  However if you have a  significant number of Radon 222 atoms ( say even a gram's worth),  you can be certain that after 3.82 days, half of them will have decayed.

[charles1948 (OP)]

Appealing to statistics is the last refuge of incompetent Physics

[chiralSPO]

Appealing to statistics is the last refuge of incompetent Physics

Apparently my statistical mechanics professor didn't know anything about physics...

And my data analysis course didn't prepare me for experiments that told me what their own results meant without my needing to muddy the water with mere significance and power testing...

[charles1948 (OP)]

If you don't mind my asking, what is a "Statistical Mechanics Professor"?  I've never heard of that occupation before, and would appreciate your enlightenment.

Does it mean, someone who designs mechanisms that may work, or not work, depending on mathematical probability-curves?

I wouldn't like someone like that designing an air-liner, or anything else mechanical for that matter.

Probably I've stupidly misunderstood what it means.  If so, put me straight please, if you feel like it.

[Halc]

1.  The replacement of Einsteinian "Relativity" by a modified form of Newtonian Mechanics

If you're bent on taking this road, why not complete it by predicting replacement of the periodic table by a modified form of Earth, Water, Wind and Fire?

[alancalverd]

Statistical mechanics is the route to understanding thermodynamics and the practical application of semiconductors.

[Colin2B]

I wouldn't like someone like that designing an air-liner, or anything else mechanical for that matter.

I’d stay away from airliners if I were you 

Bernoulli (he of the famous aerofoil theory) set it going in the 1700s by realising that for moving air or water you don’t need to know where each individual molecule is, just where statistically it is likely to be or move to. Boltzmann in the 1800s set statistical mechanics well on its way with his gas theories. It has applications not only in aeronautics but also in chemical processes, materials science, biology and most fields of science.
Statistics is at the heart of how the application of the classical, Newtonian world works and statistical mechanics led the way to quantum mechanics where you don’t need to know where or when an electron is, just where and when it is most likely to be ie statistically.

So a Statistical Mechanics Professor is someone who is an expert in that area and researches and teaches it.

[alancalverd]

How can there be any "laws" governing "randomness"?   Surely the term "random" means essentially "lawless"?

You clearly did not read the post to which you were replying. Scientific laws do not govern, they describe and predict.

Let's take a very simple example. The single toss of a coin is random, but the statistical mechanics of coins says that in a large number of trials you will approach 50% heads.

Others have quoted the random disintegration of radionuclides. In a simple case where a nucleus decays to a stable form, statistics predicts that the radiation dose rate  will decay according to an exponential law.  Using a very simple dosemeter, you can detect deviations from that law, which tell you that there is more than one nuclide present, and this can allow you to determine the source of the material.

Likewise we use statistical mechanics to decode the signal from proton spin flip, to produce an MRI image that distinguishes different tissues and fluid flow rates. The fundamental process is random but follows very well characterised laws.

[Janus]

Appealing to statistics is the last refuge of incompetent Physics

This is beginning to more and more like a simple "sour grapes" attitude.  Modern physics has grown beyond your understanding, so you you respond by claiming that modern physics isn't worth understanding.

[hamdani yusuf]

Appealing to statistics is the last refuge of incompetent Physics

I think that you want physics which describes cause and effect relationships. If x happens, then y must follow.

[Bored chemist]

Appealing to statistics is the last refuge of incompetent Physics

Demonstrably false.
You start by saying that you can't do physics.
That makes you an incompetent physicist.
Yet the appeal to statistics is not your refuge at all.

[alancalverd]

Paul Dirac gave a guest lecture at Princeton back in the day when people really did write on blackboards with chalk. At the end,  a distinguished professor said "I didn't understand the third line on the lefthand board."

Long silence, then the chairman said "Professor Dirac, do you have an answer?"

to which PD relied "It wasn't a question."

[hamdani yusuf]

At the end,  a distinguished professor said "I didn't understand the third line on the lefthand board."

It seems to me that the professor couldn't derive the equation from previous lines on the board and other underlying assumptions that he knew. It's likely that he missed some information used by Dirac to arrive at that equation. He could have expressed it in a better sentences which specify what he was missing.
I've also seen a similar situation, which turned out to be caused by some typos.

[hamdani yusuf]

Appealing to statistics is the last refuge of incompetent Physics

Demonstrably false.
You start by saying that you can't do physics.
That makes you an incompetent physicist.
Yet the appeal to statistics is not your refuge at all.

He said incompetent physics instead of physicists.
He also said about last refuge, so it's possible that he hasn't arrived there yet.
If a then b
b is the case
you shouldn't expect a

[alancalverd]

The laws of physics simply state "If a, then you are entitled to expect b because nobody has observed anything else. Yet."

Far from statistics being the last refuge of physics, the laws of physics are the first refuge of engineering. But now and again something odd happens and we revise the laws a bit.

That's what makes science interesting for scientists and really infuriating for philosophers, politicians and priests, who all demand or profess certainty.

[charles1948 (OP)]

1.  The replacement of Einsteinian "Relativity" by a modified form of Newtonian Mechanics

If you're bent on taking this road, why not complete it by predicting replacement of the periodic table by a modified form of Earth, Water, Wind and Fire?

Aren't Physicists already on the same road.  By dismissing the Chemists' Periodic Table, and actually anything else Chemists suggest, as just  "stamp-collecting".

Modern Physicists claim that everything is made of "Quarks".   Which come in 5 different "Flavours":

 - Up, Down, Top, Bottom and Strange

Is that much different from the Ancient Aristotelian Physicists who claimed that everything is made of "stuff", in
 5 different "Flavours":

- Earth, Water, Air, Fire and Celestial.

Have Physicists learned nothing in 2,000 years?  Shouldn't they take some advice from the Chemists?

[Bored chemist]

Is that much different from the Ancient Aristotelian Physicists who claimed that everything is made of "stuff", in
 5 different "Flavours":

The physicists  have evidence.

Aren't Physicists already on the same road.  By dismissing the Chemists' Periodic Table, and actually anything else Chemists suggest, as just  "stamp-collecting".

No, they aren't doing that.

Have Physicists learned nothing in 2,000 years? 

They have learned a lot.
You should try it, learning can be very satisfying.