History Biographies, History, Philosophy of Physics

[sbrothy]

Personal Memories of 50 Years of Quarkonia

The world of particle physics was revolutionised in November 1974 by the discovery of the J/psi particle, the first particle to be identified as a quarkonium state composed of charm quarks and antiquarks. The charmonium interpretation of the J/psi was cemented by the subsequent observations of a spectrum of related c \bar c states, and finally by the discovery of charmed particles in 1976. The discovery of charmonium was followed in 1977 by the discovery of bottomonium mesons and particles containing bottom quarks. Toponium bound states of top quark and antiquarks were predicted to exist in principle but, following the discovery of the top quark in 1995, most physicists thought that its observation would have to wait for next-generation e^+ e^- collider. However, in the second half of 2024 the CMS Collaboration reported an excess of events near the threshold for \bar t t production at the LHC that is most plausibly interpreted as the lowest-lying toponium state. These are the personal recollections of an eyewitness who followed closely these 50 years of quarkonium discoveries.

EDIT: Heh,. I double-posted this one. Talk about scatterbrain!

 

[sbrothy]

Two history & philosophy papers anyone with access to arXiv (read: anyone) can find. The second one provides an amusing perspective, though.


Energy as a Primitive Ontology for the Physical World

We reanalyze from a modern perspective the bold idea of G. Helm, W. Ostwald, P. Duhem and others that energy is the fundamental entity composing the physical world. We start from a broad perspective reminding the search for a fundamental ``substance'' (perhaps better referred to as ous\'ıa, the original Greek word) from the pre-Socratics to the important debate between Ostwald and Boltzmann about the energy vs. atoms at the end of the 19th century. While atoms were eventually accepted (even by Ostwald himself), the emergence of Quantum Mechanics and Relativity were crucial to suggest that the dismissal of energy in favor of atoms was perhaps premature, and should be revisited. We discuss how the so-called primitive ontology programme can be implemented with energy as the fundamental entity, and why fields (and their quanta, particles) should rather be considered as non-fundamental. We sketch some of the difficulties introduced by the attempt to include gravitation in the general scheme.

An Annotated Translation of D. Bernoulli's "A New Theory on the Motion of Waters Through Channels of Any Kind"

This paper presents an annotated English translation of Daniel Bernoulli's 1727 work A New Theory on the Motion of Waters through Channels of Any Kind, originally published in the Commentarii Academiae Scientiarum Imperialis Petropolitanae. Written over a decade before his renowned Hydrodynamica (1738), this early treatise reveals D. Bernoulli's foundational approach to fluid motion based on the conservation of vis viva-the kinetic energy of moving bodies-at a time when the principle was still under active debate. In this work, D. Bernoulli applies mechanical reasoning to fluids flowing through channels of arbitrary shape, deriving relationships between velocity, cross-sectional area, and efflux under ideal conditions. He anticipates core results of Hydrodynamica, including the inverse relationship between flow velocity and cross-sectional area, and emphasizes the role of energy balance in analyzing steady flow. The text also includes reflections on experimental limitations, the influence of friction, and the boundaries of theoretical applicability. This translation highlights the historical and conceptual significance of the 1727 paper as a precursor to D. Bernoulli's mature hydrodynamic theory.

 

[pines-demon]

• E-J Ahn, Re-remembering Benjamin Whisoh Lee, promoter of gauge theories, Physics Today (2025) 78

 

[sbrothy]

The physics, travels, and tribulations of Ronald Wilfrid Gurney

Ronald Wilfrid Gurney is one of the lesser-known research students of the Cavendish Laboratory in the mid 1920s. Gurney made significant contributions to the application of quantum mechanics to problems related to tunneling of alpha-particles from nuclei, to formation of images in photographic plates, the understanding of the origin of color-centres in salt crystals, and in the theory of semiconductors. He was the first physicist to apply quantum mechanics to the theory of electrochemistry and ionic solutions. He also made fundamental contributions to ballistics research. Gurney wrote a number of textbooks on fundamental and applied quantum mechanics in a distinctive style which are still useful as educational resources. In addition to his scientific contributions, he travelled extensively, and during and after World War II worked in the United States. During the cold war, he got entangled in the Klaus Fuchs affair and lost his employment. He died at the age of 54 in 1953 from a stroke. With the approach of the 100th year anniversary of quantum mechanics, it is timely to commemorate the life and contributions of this somewhat forgotten physicist.

 

[sbrothy]

Here's a fun one from Physics & Society:

The Devil's Dung? Money as a mechanism of generalized reciprocity in human societies

St. Francis of Assisi (1181/82-1226) famously called money the devil's dung, and indeed money is often associated with greed, inequality, and corruption. Drawing on Nowak's five rules for the evolution of cooperation, we argue here that money promotes the formation of circuits of generalized reciprocity across human groups that are fundamental to social evolution. In an evolutionary tournament, we show that money exchange is an evolutionary stable strategy that promotes cooperation without relying on the cognitive demands of direct reciprocity or reputation mechanisms. However, we also find that excessive liquidity can be detrimental because it can distort the informational value of money as a signal of past cooperation, making defection more profitable. Our results suggest that, in addition to institutions that promoted trust and punishment, the emergence of institutions that regulated the money supply was key to maintaining generalized reciprocity within and across human groups.

 

[sbrothy]

I've just read a biography of Martin Luther, albeit by a Danish author, and apart from the fact that the people back then took the devil's presence quite literally, it seems that a good defense was turning your "back" on him, whence comes the popular expression to take a s... upon something - indeed anything. On the other hand having the devil turn his "back" on you was bad news.

Must've been weird sharing your reality with devils, trolls, fairies and whatnot.

 

[sbrothy]

Epistemic Scarcity: The Economics of Unresolvable Unknowns

"This paper presents a praxeological analysis of artificial intelligence and algorithmic governance, challenging assumptions about the capacity of machine systems to sustain economic and epistemic order. Drawing on Misesian a priori reasoning and Austrian theories of entrepreneurship, we argue that AI systems are incapable of performing the core functions of economic coordination: interpreting ends, discovering means, and communicating subjective value through prices. Where neoclassical and behavioural models treat decisions as optimisation under constraint, we frame them as purposive actions under uncertainty. We critique dominant ethical AI frameworks such as Fairness, Accountability, and Transparency (FAT) as extensions of constructivist rationalism, which conflict with a liberal order grounded in voluntary action and property rights. Attempts to encode moral reasoning in algorithms reflect a misunderstanding of ethics and economics. However complex, AI systems cannot originate norms, interpret institutions, or bear responsibility. They remain opaque, misaligned, and inert. Using the concept of epistemic scarcity, we explore how information abundance degrades truth discernment, enabling both entrepreneurial insight and soft totalitarianism. Our analysis ends with a civilisational claim: the debate over AI concerns the future of human autonomy, institutional evolution, and reasoned choice. The Austrian tradition, focused on action, subjectivity, and spontaneous order, offers the only coherent alternative to rising computational social control."

I'm aware you people can just as easily find these papers if they interest you, but the word "praxeological" intrigued me. At least Merriam came back with a definition. It's not even in the British Scrabble wordlist I use to cheat at Worlde with.

 

[sbrothy]

A piece of history (boldness mine).

The Creation of Particles in an Expanding Universe

"This document is the Ph.D. thesis of Leonard Parker, submitted to Harvard University in 1966. Over the decades, several generations of physicists have been introduced to the concept of particle creation by gravitational fields, a phenomenon that has become a cornerstone in exploring the interplay between gravitation and quantum theory. Yet, the foundational breakthrough that led to the prediction and understanding of this phenomenon remains unfamiliar to many. In the interest of historical accuracy and in recognition of a seminal contribution to physics, the thesis has been retyped and made it freely available as an open-access (arXiv) document. The reissued thesis is accompanied by a Foreword that places the work in its proper historical context."

 

[sbrothy]

Some more history:

The EPR Paradox of Quantum Mechanics in the Light of Four Unpublished Letters between A. Einstein and the Mathematician J. L. B. Cooper

 

[sbrothy]

Thought I'd do a Emmy Noether "happy hour" honoring @TensorCalculus 's persistent footer signature. She (Noether!) has been mentioned before in this thread although that's no surprise considering what a giant she was in a time where - I'm sure - being a woman mathematician was no cakewalk.

"She was a contemporary of great mathematicians and physicists of the time such as Mileva Maric; Marie Curie (1867-1934), a pioneer in the field of radioactivity who won two Nobel prizes; Hilda Geiringer (1893-1973), who applied probability in the field of genetics; and Tatiana Ehrenfest-Afanassjewa (1876-1964), who worked in statistical mechanics. Also by Charlotte Angas Scott (1838-1931), a specialist in algebra and geometry and a fighter for the incorporation of women into universities.

Her predecessors with important contributions in mathematics and science were Sophia Brahe (1556-1643), Maria Cunitz (1610-1664), Elena Lucrezia Cornaro Piscopia (1646-1684), Maria Gaetana Agnesi (1718-1799) and Nicole Lepaute (1723-1788)."

---- Women's Legacy

Not the freshest papers, I'll admit, but then again it didn't happen yesterday:

Colloquium: A Century of Noether's Theorem

On the wonderfulness of Noether's theorems, 100 years later, and Routh reduction

 

[TensorCalculus]

Yes: she's such an inspiration for me!!!
Not only a woman mathematician: a Jewish woman Mathematician at the time of WW2. What a legend and so inspiring :D. Not to mention just how interesting Noether's theorems: on symmetry and conservation laws are.

I was so happy when veritasium recently did a video on Noether's theorem :D

 

[sbrothy]

A translation of the paper "Presentation of some observations that could be made to shed light on Meteorology" by Johann Heinrich Lambert (1771)

The paper is an English translation of the 1771 old-French paper by Johann Heinrich Lambert in the "Mémoires de l'Académie Royale des Sciences et Belles-Lettres de Berlin" where he imagined in a prophetic way the same present global meteorological observation system. Johann Heinrich Lambert is the same polymath who also defined the azimuthal, cylindrical and conical equal area, as well as conformal conic map projections still used in Meteorology to plot the weather maps: the so-called Lambert's projections. Note also that Lambert (1779) will derive in a next paper an absolute lower limit for the temperatures (at about -270°C), long after the first attempt by Guillaume Amontons (1703) (at about -240°C), but far before the definition by William Thomson (1848, next Lord Kelvin) of the so-called absolute Kelvin's scale of temperature still used nowadays (at about -273°C).

 

[sbrothy]

Yes: she's such an inspiration for me!!!
Not only a woman mathematician: a Jewish woman Mathematician at the time of WW2. What a legend and so inspiring :D. Not to mention just how interesting Noether's theorems: on symmetry and conservation laws are.

I was so happy when veritasium recently did a video on Noether's theorem :D

Verisitasium is a veritable goldmine unknown to me before your mention.

EDIT: Looks like TED Talks on steroids!

 

[TensorCalculus]

Verisitasium is a veritable goldmine unknown to me before your mention.

No way! Seriously?! You've missed out!
We so need to make a list of good physics YouTube channels / books / other resources to prevent such things from happening again :D

 

[sbrothy]

Indeed. There's a lot sprinkled out in this thread and others I've participated in. Mostly input from others mind.

 

[TensorCalculus]

EDIT: Looks like TED Talks on steroids!

If I get enough money, I will legitimately get "Veritasium looks like TED Talks on steroids!" printed onto a shirt I am dead serious

Edit: I have just realised custom printed tshirts are not actually that expensive at all off amazon. Now the only hurdle to overcome is my parents, and then, it is time to get the best item of clothing I have ever invested my money into

 

[Hornbein]

Yes: she's such an inspiration for me!!!
Not only a woman mathematician: a Jewish woman Mathematician at the time of WW2. What a legend and so inspiring :D. Not to mention just how interesting Noether's theorems: on symmetry and conservation laws are.

I was so happy when veritasium recently did a video on Noether's theorem :D

WW1

 

[fresh_42]

Düsseldorf.

 

[sbrothy]

Düsseldorf.

View attachment 363578

Cool street name. You sure this thread was the intended target though, or you trying to tell me something "backhandedly"?

 

[fresh_42]

Cool street name. You sure this thread was the intended target though, or you trying to tell me something "backhandedly"?

No, I just thought the title (biographies) fitted best. Just a remark about Zappa without pushing it elsewhere. It kind of belongs nowhere but I found it cool.

 

[sbrothy]

No, I just thought the title (biographies) fitted best. Just a remark about Zappa without pushing it elsewhere. It kind of belongs nowhere but I found it cool.

An indeed it is! Quite an honor for Germany to be able to name a street after him.

 

[TensorCalculus]

Düsseldorf.

View attachment 363578

ooh my parents used to live there: I'm going to ask them if they know the street name
very cool!

There's also a street named after Emmy Noether in Munich (I always love slipping in a mention of my favourite scientist/mathematician haha)

 

[sbrothy]

To derail the thread completely (why do anything half?) When I worked for Mærsk in my youth I was visited by a very religious uncle (who was having a schizoid episode, temporarily leaving his German wife and kids - without much explanation - and visiting his family up here (also) without much context).

I set up our first meeting at Søren Kierkegaard's grave on the Assistens Cemetary in the middle of Copenhagen to see if if he was receptible to constructive criticism.

A little unfair perhaps.

EDIT: Oh, and BTW he wasn't; but than again you can't reason with psychosis....

 

[fresh_42]

There's also a street named after Emmy Noether in Munich (I always love slipping in a mention of my favourite scientist/mathematician haha)

I like her, too.

I created a challenge problem especially for the 100th anniversary of her theorem.

F

Challenge Thread 'Intermediate Math Challenge - July 2018'

Jul 1, 2018

Summer is coming and brings a new intermediate math challenge! Enjoy! If you find the problems difficult to solve don't be disappointed! Just check our other basic level math challenge thread!

RULES:
1) In order for a solution to count, a full derivation or proof must be given. Answers with no proof will be ignored. Solutions will be posted around 15th of the following month.
2) It is fine to use nontrivial results without proof as long as you cite them and as long as it is "common knowledge to all mathematicians". Whether the latter is satisfied will be decided on a...

• fresh_42
• Challenge Math challenge
• Replies: 16
• Forum: Math Proof Training and Practice

• 

and a thread with a link to the original paper

F

Thread 'The Forgotten Anniversary: 100 Years since Emmy Noether's Theorems'

Feb 10, 2018

I find on a website as ours, we shouldn't have forgotten this:

On January, 25th it has been 100 years, a complete century, since Emmy Noether published her paper "Invarianten bestimmter Differentialausdrücke" (Invariants of Certain Differential Expressions, Göttingen 1918). It is still the basic concept of so many physical models, from classical mechanics to the standard model of particle physics. Funnily enough that I recently came upon an article, in which a physicist defended his opinion, that we need a new physics without symmetries. As I couldn't imagine...

• fresh_42
• Years
• Replies: 25
• Forum: Other Physics Topics

• 

@sbrothy Sorry, for this off-topic detour.

 

[sbrothy]

I like her, too.

I created a challenge problem especially for the 100th anniversary of her theorem.

F

Challenge Thread 'Intermediate Math Challenge - July 2018'

Jul 1, 2018

Summer is coming and brings a new intermediate math challenge! Enjoy! If you find the problems difficult to solve don't be disappointed! Just check our other basic level math challenge thread!

RULES:
1) In order for a solution to count, a full derivation or proof must be given. Answers with no proof will be ignored. Solutions will be posted around 15th of the following month.
2) It is fine to use nontrivial results without proof as long as you cite them and as long as it is "common knowledge to all mathematicians". Whether the latter is satisfied will be decided on a...

• fresh_42
• Challenge Math challenge
• Replies: 16
• Forum: Math Proof Training and Practice

• 

and a thread with a link to the original paper

F

Thread 'The Forgotten Anniversary: 100 Years since Emmy Noether's Theorems'

Feb 10, 2018

I find on a website as ours, we shouldn't have forgotten this:

On January, 25th it has been 100 years, a complete century, since Emmy Noether published her paper "Invarianten bestimmter Differentialausdrücke" (Invariants of Certain Differential Expressions, Göttingen 1918). It is still the basic concept of so many physical models, from classical mechanics to the standard model of particle physics. Funnily enough that I recently came upon an article, in which a physicist defended his opinion, that we need a new physics without symmetries. As I couldn't imagine...

• fresh_42
• Years
• Replies: 25
• Forum: Other Physics Topics

• 

@sbrothy Sorry, for this off-topic detour.

This sounds like a problem for @TensorCalculus. I'm afraid it's beyond me, but that wont keep me from looking at it.

 

[TensorCalculus]

I like her, too.

I created a challenge problem especially for the 100th anniversary of her theorem.

F

Challenge Thread 'Intermediate Math Challenge - July 2018'

Jul 1, 2018

Summer is coming and brings a new intermediate math challenge! Enjoy! If you find the problems difficult to solve don't be disappointed! Just check our other basic level math challenge thread!

RULES:
1) In order for a solution to count, a full derivation or proof must be given. Answers with no proof will be ignored. Solutions will be posted around 15th of the following month.
2) It is fine to use nontrivial results without proof as long as you cite them and as long as it is "common knowledge to all mathematicians". Whether the latter is satisfied will be decided on a...

• fresh_42
• Challenge Math challenge
• Replies: 16
• Forum: Math Proof Training and Practice

• 

and a thread with a link to the original paper

F

Thread 'The Forgotten Anniversary: 100 Years since Emmy Noether's Theorems'

Feb 10, 2018

I find on a website as ours, we shouldn't have forgotten this:

On January, 25th it has been 100 years, a complete century, since Emmy Noether published her paper "Invarianten bestimmter Differentialausdrücke" (Invariants of Certain Differential Expressions, Göttingen 1918). It is still the basic concept of so many physical models, from classical mechanics to the standard model of particle physics. Funnily enough that I recently came upon an article, in which a physicist defended his opinion, that we need a new physics without symmetries. As I couldn't imagine...

• fresh_42
• Years
• Replies: 25
• Forum: Other Physics Topics

• 

@sbrothy Sorry, for this off-topic detour.

Awesome! Appreciation for her is something I always like to see!

Oh wow those maths problems... the intermediate set... they look... difficult... maybe I will try the beginner set first.
Or, why not pull a classic [my name, redacted] and just dive right into the deep end, drown a couple of times, and come out gasping for air yet feeling great (this is my way of saying that why not just try the intermediate problems instead, even though I know I'm in for a bit of a rocky ride)

 

[sbrothy]

Awesome! Appreciation for her is something I always like to see!

Oh wow those maths problems... the intermediate set... they look... difficult... maybe I will try the beginner set first.
Or, why not pull a classic [my name, redacted] and just dive right into the deep end, drown a couple of times, and come out gasping for air yet feeling great (this is my way of saying that why not just try the intermediate problems instead, even though I know I'm in for a bit of a rocky ride)

Yeah. I was rather intimidated but I have confidence in you!

 

[fresh_42]

Oh wow those maths problems... the intermediate set... they look... difficult...

I guess some of them are. I tried to make many of them valuable beyond those challenges and sometimes used less-known theorems. I also used exam questions. (I looked for German ones so that common users wouldn't have found their solutions searching in English .)

Anyway, there is a solution manual available (presumably with typos):

F

Challenge Thread 'Solution Manuals For The Math Challenges'

Sep 6, 2019

We are often asked for solution manuals of various textbooks. Unfortunately we can't answer those requests, as they are either not existent, from questionable sources, or breach the copyright law. There is no other way than to contact the author or publisher in these cases.

The situation, however, is different for our own exercises. I will therefore upload solutions to math challenge questions from the past in this thread. They are not reviewed or even checked twice, so they will likely contain typos or errors. I also had some trouble with non English letters or accents. I hope I have...

• fresh_42
• Replies: 4
• Forum: Math Proof Training and Practice

• 

It has the advantage that it can be searched in a browser to look up specific topics, and it keeps frustration at bay. And if nothing else, it is a nice collection of all kinds of problems that can be used for practice purposes.

 

[sbrothy]

Yeah. I was rather intimidated but I have confidence in you!

If we teamed up we could perhaps talk circles around some of the braniacs on here with a (few) very notable exception(s) who I guess don't/doesn't want to be mentioned by me anymore, or maybe something else happened. If the former I completely I respect that. Although it might just be my scatterbrain....?

Cryptic, I know.

 

[TensorCalculus]

Yeah. I was rather intimidated but I have confidence in you!

Appreciated! I think I will need your confidence in me to be able to solve these problems

I guess some of them are. I tried to make many of them valuable beyond those challenges and sometimes used less-known theorems. I also used exam questions. (I looked for German ones so that common users wouldn't have found their solutions searching in English .)

Anyway, there is a solution manual available (presumably with typos):

F

Challenge Thread 'Solution Manuals For The Math Challenges'

Sep 6, 2019

We are often asked for solution manuals of various textbooks. Unfortunately we can't answer those requests, as they are either not existent, from questionable sources, or breach the copyright law. There is no other way than to contact the author or publisher in these cases.

The situation, however, is different for our own exercises. I will therefore upload solutions to math challenge questions from the past in this thread. They are not reviewed or even checked twice, so they will likely contain typos or errors. I also had some trouble with non English letters or accents. I hope I have...

• fresh_42
• Replies: 4
• Forum: Math Proof Training and Practice

• 

It has the advantage that it can be searched in a browser to look up specific topics, and it keeps frustration at bay. And if nothing else, it is a nice collection of all kinds of problems that can be used for practice purposes.

Okay the German thing is smart - I like that.
Not the solution manual now I have to fight the temptation to look at it every time I get frustrated (but thanks, I like being able to check my answers)

If we teamed up we could perhaps talk circles around some of the braniacs on here with a (few) very notable exception(s) who I guess don't/doesn't want to be mentioned by me anymore, or maybe something else happened. If the former I completely I respect that. Although it might just be my scatterbrain....?

Cryptic, I know.

Indeed - what do you mean by "talking circles around braniacs?"