Gernot Münster
@gernot-muenster.bsky.social
Professor for Theoretical Physics, retired, University of Münster, Center for Philosophy of Science, #WeStandWithUkraine
https://www.uni-muenster.de/Physik.TP/~munsteg/
https://www.uni-muenster.de/Physik.TP/~munsteg/
⚛️ After a long summer break, more physics stories.
Find previous ones in my timeline.
Houtermans and the Lifespan of the Sun
In the 1950s, Fritz Houtermans was sitting in a café in Bern with a colleague, explaining how long, according to his calculations, the sun will continue to shine.
1/2
Find previous ones in my timeline.
Houtermans and the Lifespan of the Sun
In the 1950s, Fritz Houtermans was sitting in a café in Bern with a colleague, explaining how long, according to his calculations, the sun will continue to shine.
1/2
November 26, 2025 at 10:45 AM
⚛️ After a long summer break, more physics stories.
Find previous ones in my timeline.
Houtermans and the Lifespan of the Sun
In the 1950s, Fritz Houtermans was sitting in a café in Bern with a colleague, explaining how long, according to his calculations, the sun will continue to shine.
1/2
Find previous ones in my timeline.
Houtermans and the Lifespan of the Sun
In the 1950s, Fritz Houtermans was sitting in a café in Bern with a colleague, explaining how long, according to his calculations, the sun will continue to shine.
1/2
This one provides the theoretical framework.
November 25, 2025 at 2:44 PM
This one provides the theoretical framework.
⚛️ Nice rainbow yesterday. You can clearly see Alexander’s band, the darker region between the inner primary rainbow and the outer one.
August 7, 2025 at 7:41 PM
⚛️ Nice rainbow yesterday. You can clearly see Alexander’s band, the darker region between the inner primary rainbow and the outer one.
⚛️ Pauli effect 3
(Find previous ones in my timeline.)
One afternoon, in the late 1920s or early 1930s, a complicated apparatus exploded in the laboratory of physicist James Franck at the University of Göttingen. Franck reported the mishap to Pauli, who lived in Zurich, in a letter,
1/3
(Find previous ones in my timeline.)
One afternoon, in the late 1920s or early 1930s, a complicated apparatus exploded in the laboratory of physicist James Franck at the University of Göttingen. Franck reported the mishap to Pauli, who lived in Zurich, in a letter,
1/3
April 8, 2025 at 8:13 PM
⚛️ Pauli effect 3
(Find previous ones in my timeline.)
One afternoon, in the late 1920s or early 1930s, a complicated apparatus exploded in the laboratory of physicist James Franck at the University of Göttingen. Franck reported the mishap to Pauli, who lived in Zurich, in a letter,
1/3
(Find previous ones in my timeline.)
One afternoon, in the late 1920s or early 1930s, a complicated apparatus exploded in the laboratory of physicist James Franck at the University of Göttingen. Franck reported the mishap to Pauli, who lived in Zurich, in a letter,
1/3
the ratio
R = - log(|pi - p/q|) / log(pq). For 22/7, R = 1.325, and for 355/113, R = 1.428.
Can it get any more efficient?
The best rational approximations for irrational numbers are provided by regular continued fractions. For pi it is shown in the figure.
4/7
R = - log(|pi - p/q|) / log(pq). For 22/7, R = 1.325, and for 355/113, R = 1.428.
Can it get any more efficient?
The best rational approximations for irrational numbers are provided by regular continued fractions. For pi it is shown in the figure.
4/7
March 14, 2025 at 6:32 PM
the ratio
R = - log(|pi - p/q|) / log(pq). For 22/7, R = 1.325, and for 355/113, R = 1.428.
Can it get any more efficient?
The best rational approximations for irrational numbers are provided by regular continued fractions. For pi it is shown in the figure.
4/7
R = - log(|pi - p/q|) / log(pq). For 22/7, R = 1.325, and for 355/113, R = 1.428.
Can it get any more efficient?
The best rational approximations for irrational numbers are provided by regular continued fractions. For pi it is shown in the figure.
4/7
Lucy Mensing, vergessene Pionierin der Quantenmechanik ⚛️
#OTD wurde Lucy Mensing 1901 in Hamburg geboren. In den 1920er Jahren leistete sie fundamentale Beiträge zur neuen Quantenmechanik. Dennoch ist sie heute fast ganz vergessen. Was hat sie beigetragen und was führte zum Ende
1/9
#OTD wurde Lucy Mensing 1901 in Hamburg geboren. In den 1920er Jahren leistete sie fundamentale Beiträge zur neuen Quantenmechanik. Dennoch ist sie heute fast ganz vergessen. Was hat sie beigetragen und was führte zum Ende
1/9
March 11, 2025 at 3:29 PM
Lucy Mensing, vergessene Pionierin der Quantenmechanik ⚛️
#OTD wurde Lucy Mensing 1901 in Hamburg geboren. In den 1920er Jahren leistete sie fundamentale Beiträge zur neuen Quantenmechanik. Dennoch ist sie heute fast ganz vergessen. Was hat sie beigetragen und was führte zum Ende
1/9
#OTD wurde Lucy Mensing 1901 in Hamburg geboren. In den 1920er Jahren leistete sie fundamentale Beiträge zur neuen Quantenmechanik. Dennoch ist sie heute fast ganz vergessen. Was hat sie beigetragen und was führte zum Ende
1/9
Lucy Mensing, forgotten pioneer of quantum mechanics ⚛️
Lucy Mensing was born #OTD in Hamburg in 1901. In the 1920s she made fundamental contributions to the new quantum mechanics. Nevertheless, she is almost completely forgotten today. What did she contribute and what led
1/8
Lucy Mensing was born #OTD in Hamburg in 1901. In the 1920s she made fundamental contributions to the new quantum mechanics. Nevertheless, she is almost completely forgotten today. What did she contribute and what led
1/8
March 11, 2025 at 3:20 PM
Lucy Mensing, forgotten pioneer of quantum mechanics ⚛️
Lucy Mensing was born #OTD in Hamburg in 1901. In the 1920s she made fundamental contributions to the new quantum mechanics. Nevertheless, she is almost completely forgotten today. What did she contribute and what led
1/8
Lucy Mensing was born #OTD in Hamburg in 1901. In the 1920s she made fundamental contributions to the new quantum mechanics. Nevertheless, she is almost completely forgotten today. What did she contribute and what led
1/8
Physics stories ⚛️
Pauli, Dirac, and pieces of sugar
I met Carl Friedrich von Weizsäcker several times. Once he told the following story. There was a meeting in Copenhagen, where Wolfgang Pauli, P.A.M. Dirac and others discussed physics. Pauli was drinking tea.
1/4
Pauli, Dirac, and pieces of sugar
I met Carl Friedrich von Weizsäcker several times. Once he told the following story. There was a meeting in Copenhagen, where Wolfgang Pauli, P.A.M. Dirac and others discussed physics. Pauli was drinking tea.
1/4
March 6, 2025 at 9:44 AM
Physics stories ⚛️
Pauli, Dirac, and pieces of sugar
I met Carl Friedrich von Weizsäcker several times. Once he told the following story. There was a meeting in Copenhagen, where Wolfgang Pauli, P.A.M. Dirac and others discussed physics. Pauli was drinking tea.
1/4
Pauli, Dirac, and pieces of sugar
I met Carl Friedrich von Weizsäcker several times. Once he told the following story. There was a meeting in Copenhagen, where Wolfgang Pauli, P.A.M. Dirac and others discussed physics. Pauli was drinking tea.
1/4
There are numerous attempts to represent the value of the fine structure constant using simple formulas. For example, A. Wyler published the following expression for this in 1969. However, it turns out that you can find many such formulas without there being anything behind them.
7/9
7/9
February 7, 2025 at 10:55 AM
There are numerous attempts to represent the value of the fine structure constant using simple formulas. For example, A. Wyler published the following expression for this in 1969. However, it turns out that you can find many such formulas without there being anything behind them.
7/9
7/9
He even discussed with the psychoanalyst C.G. Jung the possible special meaning of the number 137, and related it with the Kabbalah. Before his death in 1958, he was placed in room number 137 in a hospital in Zurich, which really worried him.
6/9
6/9
February 7, 2025 at 10:55 AM
He even discussed with the psychoanalyst C.G. Jung the possible special meaning of the number 137, and related it with the Kabbalah. Before his death in 1958, he was placed in room number 137 in a hospital in Zurich, which really worried him.
6/9
6/9
whether there is a special reason behind this number. Arthur S. Eddington, who is widely known for measuring the deflection of light near the sun in 1919, published an obscure derivation in 1918, according to which the exact value should be 136.
4/9
4/9
February 7, 2025 at 10:55 AM
whether there is a special reason behind this number. Arthur S. Eddington, who is widely known for measuring the deflection of light near the sun in 1919, published an obscure derivation in 1918, according to which the exact value should be 136.
4/9
4/9
is of fundamental importance for physics. Richard Feynman writes: "It has been a mystery ever since it was discovered more than fifty years ago. Immediately you would like to know where this number for a coupling comes from. Nobody knows.
2/9
2/9
February 7, 2025 at 10:55 AM
is of fundamental importance for physics. Richard Feynman writes: "It has been a mystery ever since it was discovered more than fifty years ago. Immediately you would like to know where this number for a coupling comes from. Nobody knows.
2/9
2/9
Harry Lehmann (my graduate father), who was present and knew Weizsäcker from their time in Göttingen, shouted "minus one". In response to Weizsäcker's astonished question, "What do you mean, Mr. Lehmann?",
9/10
9/10
January 12, 2025 at 11:27 AM
Harry Lehmann (my graduate father), who was present and knew Weizsäcker from their time in Göttingen, shouted "minus one". In response to Weizsäcker's astonished question, "What do you mean, Mr. Lehmann?",
9/10
9/10
Anecdote 2: In the 1950s, the physicist and philosopher Carl Friedrich von Weizsäcker proposed a theory of the universe that is based on so-called quantum theoretical "ur-alternatives". An alternative is a yes-no question.
7/10
7/10
January 12, 2025 at 11:27 AM
Anecdote 2: In the 1950s, the physicist and philosopher Carl Friedrich von Weizsäcker proposed a theory of the universe that is based on so-called quantum theoretical "ur-alternatives". An alternative is a yes-no question.
7/10
7/10
Anecdote 1: When Wolfgang Pauli heard of Jordan's theory that the mass of the universe increases quadratically with time, he commented on it with regard to Jordan's ever-increasing corpulence with the remark that it was pure anthropomorphism: Jordan was projecting his own development onto space.
January 12, 2025 at 11:27 AM
Anecdote 1: When Wolfgang Pauli heard of Jordan's theory that the mass of the universe increases quadratically with time, he commented on it with regard to Jordan's ever-increasing corpulence with the remark that it was pure anthropomorphism: Jordan was projecting his own development onto space.
Physics stories ⚛️
Dirac, the large numbers, and two anecdotes
The physicist Dirac, pioneer of quantum theory, discoverer of the Dirac equation and Nobel Prize winner, pointed out the following remarkable facts in 1937:
1/10
Dirac, the large numbers, and two anecdotes
The physicist Dirac, pioneer of quantum theory, discoverer of the Dirac equation and Nobel Prize winner, pointed out the following remarkable facts in 1937:
1/10
January 12, 2025 at 11:20 AM
Physics stories ⚛️
Dirac, the large numbers, and two anecdotes
The physicist Dirac, pioneer of quantum theory, discoverer of the Dirac equation and Nobel Prize winner, pointed out the following remarkable facts in 1937:
1/10
Dirac, the large numbers, and two anecdotes
The physicist Dirac, pioneer of quantum theory, discoverer of the Dirac equation and Nobel Prize winner, pointed out the following remarkable facts in 1937:
1/10
When I met Einstein
January 5, 2025 at 3:49 PM
When I met Einstein
In special cases, the later parts of the pulse may be suppressed, see illustration.
9/11
9/11
January 4, 2025 at 3:58 PM
In special cases, the later parts of the pulse may be suppressed, see illustration.
9/11
9/11
So here is a brief explanation of negative group delay.
A signal does not come instantaneously, but as a pulse with finite temporal extension. The figure shows an example of the temporal form of a pulse.
7/11
A signal does not come instantaneously, but as a pulse with finite temporal extension. The figure shows an example of the temporal form of a pulse.
7/11
January 4, 2025 at 3:58 PM
So here is a brief explanation of negative group delay.
A signal does not come instantaneously, but as a pulse with finite temporal extension. The figure shows an example of the temporal form of a pulse.
7/11
A signal does not come instantaneously, but as a pulse with finite temporal extension. The figure shows an example of the temporal form of a pulse.
7/11
"Negative time" in quantum physics?
In the fall of 2024, a physics experiment hit the headlines. News portals such as London Daily News, NDTV, The Independent, Science Alert and others reported on the discovery of “negative time”,
1/11
In the fall of 2024, a physics experiment hit the headlines. News portals such as London Daily News, NDTV, The Independent, Science Alert and others reported on the discovery of “negative time”,
1/11
January 4, 2025 at 3:58 PM
"Negative time" in quantum physics?
In the fall of 2024, a physics experiment hit the headlines. News portals such as London Daily News, NDTV, The Independent, Science Alert and others reported on the discovery of “negative time”,
1/11
In the fall of 2024, a physics experiment hit the headlines. News portals such as London Daily News, NDTV, The Independent, Science Alert and others reported on the discovery of “negative time”,
1/11
What is this? Strange attractor? Poincare map? Vortex turbulence?
December 31, 2024 at 11:03 AM
What is this? Strange attractor? Poincare map? Vortex turbulence?
Physics stories ⚛️
Pauli effect 1
Wolfgang Pauli is known, among other things, for the Pauli principle, for which he was awarded the Nobel Prize in 1945. He was proud of the Pauli effect: when he was in or near a laboratory, experiments often failed or equipment broke down.
1/3
Pauli effect 1
Wolfgang Pauli is known, among other things, for the Pauli principle, for which he was awarded the Nobel Prize in 1945. He was proud of the Pauli effect: when he was in or near a laboratory, experiments often failed or equipment broke down.
1/3
December 8, 2024 at 5:15 PM
Physics stories ⚛️
Pauli effect 1
Wolfgang Pauli is known, among other things, for the Pauli principle, for which he was awarded the Nobel Prize in 1945. He was proud of the Pauli effect: when he was in or near a laboratory, experiments often failed or equipment broke down.
1/3
Pauli effect 1
Wolfgang Pauli is known, among other things, for the Pauli principle, for which he was awarded the Nobel Prize in 1945. He was proud of the Pauli effect: when he was in or near a laboratory, experiments often failed or equipment broke down.
1/3
Am meisten interessieren mich der Riemann-Tensor und der Energie-Impuls-Tensor.
December 8, 2024 at 11:39 AM
Am meisten interessieren mich der Riemann-Tensor und der Energie-Impuls-Tensor.
Auf in den Süden, zu Hunderten!
November 30, 2024 at 11:47 AM
Auf in den Süden, zu Hunderten!
