"El cosmos es todo lo que es, todo lo que fue y todo lo que será. Nuestras más ligeras contemplaciones del cosmos nos hacen estremecer; sentimos como un cosquilleo nos llena los nervios, una voz muda, una ligera sensación como de un recuerdo lejano o como si cayéramos desde gran altura. Sabemos que nos aproximamos al más grande de los misterios."
Carl Sagan
Happy pi approximation day!
Today's date, 22 July, can also be written as the fraction 22/7, which is equal to 3.14285714, an approximation of π, correct to two decimal places.
@PhysInHistory One of the biggest open questions is why the vacuum energy predicted by quantum field theory differs so dramatically from the observed value associated with dark energy.
"En cada rama del conocimiento, el progreso es proporcional a la cantidad de hechos sobre los cuales se puede razonar y, por tanto, al desarrollo de las matemáticas. En una ciencia, las matemáticas son simplemente la medida exacta de nuestro conocimiento."
James Clerk Maxwell
The Feynman point is the name given to the position in the decimal expansion of π where a sequence of six consecutive nines first appears. It is named after the physicist Richard Feynman, who allegedly joked that he would like to memorize the digits of pi up to that point and then say “and so on” as if π. were rational. The Feynman point occurs at the 762nd digit after the decimal point, which is much earlier than expected by chance.
Prepara un café, ponte los audífonos y acompaña a Paul Dirac durante una hora de mecánica cuántica.
Una oportunidad para escuchar a una de las mentes más brillantes del siglo XX explicar las ideas que transformaron nuestra comprensión del universo. Un contenido ideal para quienes disfrutan aprender física desde sus protagonistas.
#Physics #QuantumMechanics #PaulDirac #Science #STEM #PhysicsEducation
First use of Zero in Europe ✍️
The first recorded use of zero in Europe is attributed to the Italian mathematician Leonardo of Pisa, known as Fibonacci, in his book Liber Abaci (1202). This book introduced the Hindu-Arabic numeral system, including zero, to European mathematics, replacing the cumbersome Roman numerals.
Fibonacci had learned about this system during his travels in North Africa, where he studied under Arab mathematicians. While zero had been used in Indian mathematics since the 5th century and was later transmitted to the Islamic world, Liber Abaci played a pivotal role in spreading its practical utility for commerce and calculations across medieval Europe.
Small differences at the outset can send a system down entirely different paths later.
The left panel shows the butterfly effect through two trajectories that start nearly together yet separate widely as time progresses.
The center panel displays the Lorenz attractor, the well-known butterfly-shaped strange attractor produced by the Lorenz equations for fluid convection.
The right panel shows the Rössler attractor, another strange attractor from the Rössler system, with its distinctive spiraling structure in three-dimensional phase space.
It is used to refine weather prediction models and to examine irregular rhythms in chemical reactions and biological populations.
Mikhail Leonidovich Gromov, commonly known as Mikhail Gromov, was born on December 23, 1943, in Boksitogorsk, Russian SFSR, Soviet Union.
In Riemannian geometry and geometric group theory, Gromov introduced the Gromov-Hausdorff distance between metric spaces and established associated compactness theorems for sequences of Riemannian manifolds with bounded Ricci curvature and diameter. He proved that every finitely generated group of polynomial growth is virtually nilpotent, thereby resolving the Milnor-Wolf conjecture.
In symplectic geometry, Gromov founded a major new direction in 1985 by introducing the theory of pseudoholomorphic curves, also called J-holomorphic curves, on symplectic manifolds. This framework led directly to the definition of Gromov-Witten invariants and the creation of modern symplectic topology, with applications extending to string theory and quantum field theory.
Gromov has received many major awards recognizing his mathematical achievements. These include the Oswald Veblen Prize in Geometry in 1981, the Wolf Prize in Mathematics in 1993, the Balzan Prize in 1999, the Kyoto Prize in 2002, and the Nemmers Prize in 2004. In 2009 he was awarded the Abel Prize by the Norwegian Academy of Science and Letters for his revolutionary contributions to geometry.
Since the atomic bombings in 1945, nuclear weapons have posed a significant threat to humanity. On 7 July 2017, the Treaty on the Prohibition of Nuclear Weapons was adopted. It was the first multilateral legally-binding instrument for nuclear disarmament negotiated in 20 years.
¿Cuál es la ecuación más bella de la física?
Muchos físicos responderían sin dudar: la ecuación de Dirac.
No solo porque describe con una precisión extraordinaria el comportamiento del electrón, sino porque logró unir dos de las teorías más importantes del siglo XX: la mecánica cuántica y la relatividad especial de Albert Einstein.
En su forma más compacta, la ecuación se escribe así:
---Observar la Imagen---
En conjunto, la ecuación describe cómo evoluciona un electrón moviéndose a velocidades cercanas a la de la luz.
Hasta 1928 existían dos teorías extraordinarias, pero incompatibles entre sí: la mecánica cuántica describía el mundo microscópico, mientras que la relatividad especial describía el movimiento a altas velocidades.
Paul Dirac encontró una ecuación que respetaba ambas al mismo tiempo. Fue un logro matemático y físico sin precedentes.
Pero lo más increíble ocurrió después.
Al resolver la ecuación aparecían soluciones con energía negativa. Muchos pensaron que era un error matemático.
Dirac propuso una idea revolucionaria: esas soluciones correspondían a una partícula completamente nueva, con la misma masa que el electrón, pero con carga positiva.
En ese momento nadie había observado algo semejante.
Cuatro años más tarde, en 1932, Carl Anderson detectó experimentalmente esa partícula en los rayos cósmicos: el positrón, la primera antipartícula descubierta.
La ecuación había predicho la existencia de una partícula antes de que cualquier experimento pudiera verla.
Fue una de las mayores victorias de la física teórica.
Por eso muchos consideran que la ecuación de Dirac es la más bella de la historia: no solo explica la naturaleza con elegancia matemática, sino que también fue capaz de revelar un aspecto completamente desconocido del universo.
"Las leyes fundamentales necesarias para gran parte de la física y toda la química son completamente conocidas; el problema es que estas leyes conducen a ecuaciones demasiado difíciles de resolver."
Paul Dirac
#Physics #Física #Dirac #MecánicaCuántica #HistoriaDeLaCiencia #Ciencia #IngenieríaFísica
Why do the laws of physics fail at Singularity? ✍️
The laws of physics break down at singularities because the extreme conditions there exceed the limits of our current understanding of the universe. Singularities, such as the center of a black hole or the moment of the Big Bang, are points where density becomes infinite, and spacetime curvature becomes immeasurable.
Here’s why they defy physics:
1. General Relativity Fails: Einstein’s equations can’t handle infinite values, rendering them ineffective in such conditions.
2. Quantum Mechanics Takes Over: At very small scales, quantum effects dominate, but we lack a complete theory of quantum gravity to unify it with relativity.
3. Infinite Spacetime Distortion: The extreme curvature of spacetime at singularities breaks conventional mathematical models.
4. Observational Limits: Singularities are often hidden by event horizons (like in black holes), making direct study impossible.
Max Planck was a musical prodigy who could play the piano, organ, and cello. He even composed his own songs and operas. He once said,
“The main source of all the greatest achievements in natural science, I am convinced, lies in the divine gift of musicality.”