Jacopo Bertolotti
@jacopobertolotti.com
Associated Professor of Physics at the University of Exeter.
Scientific visualizations (grouped under the hastag #PhysicsFactlet).
He/lui/on. All opinions are my own fault.
Scientific visualizations (grouped under the hastag #PhysicsFactlet).
He/lui/on. All opinions are my own fault.
October 18, 2025 at 2:25 PM
#PhysicsFactlet
In its simplest form Monte-Carlo integration allows to estimate a area/volume with complicated boundaries by taking a number of samples and looking at which fraction fall inside the object of interest.
🎢🧪⚛️ #ComputationalPhysics
In its simplest form Monte-Carlo integration allows to estimate a area/volume with complicated boundaries by taking a number of samples and looking at which fraction fall inside the object of interest.
🎢🧪⚛️ #ComputationalPhysics
October 17, 2025 at 10:29 AM
#PhysicsFactlet
In its simplest form Monte-Carlo integration allows to estimate a area/volume with complicated boundaries by taking a number of samples and looking at which fraction fall inside the object of interest.
🎢🧪⚛️ #ComputationalPhysics
In its simplest form Monte-Carlo integration allows to estimate a area/volume with complicated boundaries by taking a number of samples and looking at which fraction fall inside the object of interest.
🎢🧪⚛️ #ComputationalPhysics
#PhysicsFactlet
Sometimes you need to forego the intuitive way to define stuff for the sake of actually being able to do anything useful with those definitions.
#knots 🧪 🎢
🧵1/
Sometimes you need to forego the intuitive way to define stuff for the sake of actually being able to do anything useful with those definitions.
#knots 🧪 🎢
🧵1/
October 13, 2025 at 1:29 PM
#PhysicsFactlet
Sometimes you need to forego the intuitive way to define stuff for the sake of actually being able to do anything useful with those definitions.
#knots 🧪 🎢
🧵1/
Sometimes you need to forego the intuitive way to define stuff for the sake of actually being able to do anything useful with those definitions.
#knots 🧪 🎢
🧵1/
#PhysicsFactlet
A geodesics on a surface is the shortest* curve connecting two points.
*if you know/care what goes in this footnote, you don't need me to explain 😉
A geodesics on a surface is the shortest* curve connecting two points.
*if you know/care what goes in this footnote, you don't need me to explain 😉
October 3, 2025 at 1:38 PM
#PhysicsFactlet
A geodesics on a surface is the shortest* curve connecting two points.
*if you know/care what goes in this footnote, you don't need me to explain 😉
A geodesics on a surface is the shortest* curve connecting two points.
*if you know/care what goes in this footnote, you don't need me to explain 😉
This non-randomness has a number of consequences, among them the fact that the you get predictable patterns in the apparently random output. We show that a focused input will always result in a ring of excess intensity at the same radius of the input (and suggest how this might be useful).
2/2
2/2
August 18, 2025 at 2:12 PM
This non-randomness has a number of consequences, among them the fact that the you get predictable patterns in the apparently random output. We show that a focused input will always result in a ring of excess intensity at the same radius of the input (and suggest how this might be useful).
2/2
2/2
#PhysicsFactlet
The most naïve way to integrate (ordinary) differential equations, is to use the instantaneous velocity to update the position, and the instantaneous force to update the velocity (Euler method). While this is simple and intuitive, it accumulates errors very quickly.
🎢⚛️
The most naïve way to integrate (ordinary) differential equations, is to use the instantaneous velocity to update the position, and the instantaneous force to update the velocity (Euler method). While this is simple and intuitive, it accumulates errors very quickly.
🎢⚛️
August 15, 2025 at 10:06 AM
#PhysicsFactlet
The most naïve way to integrate (ordinary) differential equations, is to use the instantaneous velocity to update the position, and the instantaneous force to update the velocity (Euler method). While this is simple and intuitive, it accumulates errors very quickly.
🎢⚛️
The most naïve way to integrate (ordinary) differential equations, is to use the instantaneous velocity to update the position, and the instantaneous force to update the velocity (Euler method). While this is simple and intuitive, it accumulates errors very quickly.
🎢⚛️
#PhysicsFactlet
Thanks to some humidity in the air the air flow around the plane wing is clearly visible. Instead of just being deflected by the wing, the air flow tend to stick to the wing (and vice versa), which pulls the wing up and allow the plane to fly.
⚛️🎢
Thanks to some humidity in the air the air flow around the plane wing is clearly visible. Instead of just being deflected by the wing, the air flow tend to stick to the wing (and vice versa), which pulls the wing up and allow the plane to fly.
⚛️🎢
July 25, 2025 at 2:53 PM
#PhysicsFactlet
Thanks to some humidity in the air the air flow around the plane wing is clearly visible. Instead of just being deflected by the wing, the air flow tend to stick to the wing (and vice versa), which pulls the wing up and allow the plane to fly.
⚛️🎢
Thanks to some humidity in the air the air flow around the plane wing is clearly visible. Instead of just being deflected by the wing, the air flow tend to stick to the wing (and vice versa), which pulls the wing up and allow the plane to fly.
⚛️🎢
#PhysicsFactlet
If evaluating the derivative of your function is not too computationally expensive, one can use the crossing point of the tangent line with the axis as your next best guess ("Newton-Raphson).
⚛️🎢
If evaluating the derivative of your function is not too computationally expensive, one can use the crossing point of the tangent line with the axis as your next best guess ("Newton-Raphson).
⚛️🎢
July 21, 2025 at 8:56 AM
#PhysicsFactlet
If evaluating the derivative of your function is not too computationally expensive, one can use the crossing point of the tangent line with the axis as your next best guess ("Newton-Raphson).
⚛️🎢
If evaluating the derivative of your function is not too computationally expensive, one can use the crossing point of the tangent line with the axis as your next best guess ("Newton-Raphson).
⚛️🎢
#PhysicsFactlet
The "false position" method works great if the function is roughly linear in the bracketed region, so why don't we multiply by a function (of constant sign, so we don't add spurious zeros) that makes it more linear before applying it?
This is the "Ridders' method"
⚛️🎢
The "false position" method works great if the function is roughly linear in the bracketed region, so why don't we multiply by a function (of constant sign, so we don't add spurious zeros) that makes it more linear before applying it?
This is the "Ridders' method"
⚛️🎢
July 18, 2025 at 8:37 AM
#PhysicsFactlet
The "false position" method works great if the function is roughly linear in the bracketed region, so why don't we multiply by a function (of constant sign, so we don't add spurious zeros) that makes it more linear before applying it?
This is the "Ridders' method"
⚛️🎢
The "false position" method works great if the function is roughly linear in the bracketed region, so why don't we multiply by a function (of constant sign, so we don't add spurious zeros) that makes it more linear before applying it?
This is the "Ridders' method"
⚛️🎢
#PhysicsFactlet
An improvement over the bisection method is the so-called "false position" method, where instead of dividing the bracket region in two, you cut at the point where the line through the two bracket extremes crosses zero.
⚛️🎢
An improvement over the bisection method is the so-called "false position" method, where instead of dividing the bracket region in two, you cut at the point where the line through the two bracket extremes crosses zero.
⚛️🎢
July 17, 2025 at 9:47 AM
#PhysicsFactlet
An improvement over the bisection method is the so-called "false position" method, where instead of dividing the bracket region in two, you cut at the point where the line through the two bracket extremes crosses zero.
⚛️🎢
An improvement over the bisection method is the so-called "false position" method, where instead of dividing the bracket region in two, you cut at the point where the line through the two bracket extremes crosses zero.
⚛️🎢
I am not sure if anybody will be surprised to hear this, but Microsoft can not (and will not) guarantee that your data will not be handed to a foreign authority without your government permission.
#Microsoft #GDPR #DataSecurity
www.senat.fr/fileadmin/cr...
#Microsoft #GDPR #DataSecurity
www.senat.fr/fileadmin/cr...
July 17, 2025 at 8:34 AM
I am not sure if anybody will be surprised to hear this, but Microsoft can not (and will not) guarantee that your data will not be handed to a foreign authority without your government permission.
#Microsoft #GDPR #DataSecurity
www.senat.fr/fileadmin/cr...
#Microsoft #GDPR #DataSecurity
www.senat.fr/fileadmin/cr...
And today Dr Mounaix is at @exeter.ac.uk telling us about spatiotemporal beams in optical fibres!
#Physics #Optics
#Physics #Optics
July 15, 2025 at 11:07 AM
And today Dr Mounaix is at @exeter.ac.uk telling us about spatiotemporal beams in optical fibres!
#Physics #Optics
#Physics #Optics
#PhysicsFactlet
The bisection method is a simple and effective way to find the root(s) of a function
The idea is that you start by "bracketing" your root . You then take the midpoint between them, check if your function there is positive or negative and update the bracket.
⚛️🎢 #Computing #Algorithm
The bisection method is a simple and effective way to find the root(s) of a function
The idea is that you start by "bracketing" your root . You then take the midpoint between them, check if your function there is positive or negative and update the bracket.
⚛️🎢 #Computing #Algorithm
July 11, 2025 at 1:02 PM
#PhysicsFactlet
The bisection method is a simple and effective way to find the root(s) of a function
The idea is that you start by "bracketing" your root . You then take the midpoint between them, check if your function there is positive or negative and update the bracket.
⚛️🎢 #Computing #Algorithm
The bisection method is a simple and effective way to find the root(s) of a function
The idea is that you start by "bracketing" your root . You then take the midpoint between them, check if your function there is positive or negative and update the bracket.
⚛️🎢 #Computing #Algorithm
#PhysicsFactlet
#PhysicsFactlet
Optical fibre modes are weird but oddly mesmerizing.
#Optics #OpticalFibers
#PhysicsFactlet
Optical fibre modes are weird but oddly mesmerizing.
#Optics #OpticalFibers
June 25, 2025 at 2:23 PM
#PhysicsFactlet
#PhysicsFactlet
Optical fibre modes are weird but oddly mesmerizing.
#Optics #OpticalFibers
#PhysicsFactlet
Optical fibre modes are weird but oddly mesmerizing.
#Optics #OpticalFibers
#ITeachPhysics
Currently preparing my first lecture for a "Computational Physics" module. Topic of the lecture: interpolation.
Currently preparing my first lecture for a "Computational Physics" module. Topic of the lecture: interpolation.
June 17, 2025 at 8:42 AM
#ITeachPhysics
Currently preparing my first lecture for a "Computational Physics" module. Topic of the lecture: interpolation.
Currently preparing my first lecture for a "Computational Physics" module. Topic of the lecture: interpolation.
Somehow in my mind I didn't play with my #Xbox360 for very long, but I am now in the process of clearing up a bit of space in the house, and I realized my pile of xbox360 games is surprisingly tall for someone who generally has very little time to play.
🎮
🎮
May 31, 2025 at 10:37 AM
Somehow in my mind I didn't play with my #Xbox360 for very long, but I am now in the process of clearing up a bit of space in the house, and I realized my pile of xbox360 games is surprisingly tall for someone who generally has very little time to play.
🎮
🎮
#PhysicsFactlet
Wavefront Shaping is a family of techniques used to control light (or, more generally, a wave) propagating through a scattering medium.
A 🧵
1/
🧪⚛️🎢💡
Wavefront Shaping is a family of techniques used to control light (or, more generally, a wave) propagating through a scattering medium.
A 🧵
1/
🧪⚛️🎢💡
May 30, 2025 at 10:57 AM
#PhysicsFactlet
Wavefront Shaping is a family of techniques used to control light (or, more generally, a wave) propagating through a scattering medium.
A 🧵
1/
🧪⚛️🎢💡
Wavefront Shaping is a family of techniques used to control light (or, more generally, a wave) propagating through a scattering medium.
A 🧵
1/
🧪⚛️🎢💡
#PhysicsFactlet
A Shack-Hartmann sensor is a simple and widely used device to measure the phase profile of a wavefront (aka "where the light is coming from").
A mini 🧵
1/
#Optics #Physics
A Shack-Hartmann sensor is a simple and widely used device to measure the phase profile of a wavefront (aka "where the light is coming from").
A mini 🧵
1/
#Optics #Physics
May 27, 2025 at 9:28 AM
#PhysicsFactlet
A Shack-Hartmann sensor is a simple and widely used device to measure the phase profile of a wavefront (aka "where the light is coming from").
A mini 🧵
1/
#Optics #Physics
A Shack-Hartmann sensor is a simple and widely used device to measure the phase profile of a wavefront (aka "where the light is coming from").
A mini 🧵
1/
#Optics #Physics
#PhysicsFactlet
A Stone-Wales defect is a 90 degrees rotation of a chemical bond between two carbon atoms that commonly happens in graphene and fullerene.
#Crystallography #Chemistry #Physics
A Stone-Wales defect is a 90 degrees rotation of a chemical bond between two carbon atoms that commonly happens in graphene and fullerene.
#Crystallography #Chemistry #Physics
May 19, 2025 at 9:37 AM
#PhysicsFactlet
A Stone-Wales defect is a 90 degrees rotation of a chemical bond between two carbon atoms that commonly happens in graphene and fullerene.
#Crystallography #Chemistry #Physics
A Stone-Wales defect is a 90 degrees rotation of a chemical bond between two carbon atoms that commonly happens in graphene and fullerene.
#Crystallography #Chemistry #Physics
#PhysicsFactlet
Remake of an old animation about quantum tunnelling in the time domain.
🧪⚛️💡
A few details:
* The incident and reflected wavefunctions interfere, creating fringes when it hits the barrier.
* Even when far away from the barrier, the wavefunction is slowly broadening.
Remake of an old animation about quantum tunnelling in the time domain.
🧪⚛️💡
A few details:
* The incident and reflected wavefunctions interfere, creating fringes when it hits the barrier.
* Even when far away from the barrier, the wavefunction is slowly broadening.
March 12, 2025 at 3:54 PM
#PhysicsFactlet
Remake of an old animation about quantum tunnelling in the time domain.
🧪⚛️💡
A few details:
* The incident and reflected wavefunctions interfere, creating fringes when it hits the barrier.
* Even when far away from the barrier, the wavefunction is slowly broadening.
Remake of an old animation about quantum tunnelling in the time domain.
🧪⚛️💡
A few details:
* The incident and reflected wavefunctions interfere, creating fringes when it hits the barrier.
* Even when far away from the barrier, the wavefunction is slowly broadening.
In this paper we show (simulations only so far, but the experimental results are coming) how to design a structure that is either transparent, or highlight the edges of any image passing through it.
5/5
5/5
February 24, 2025 at 3:42 PM
In this paper we show (simulations only so far, but the experimental results are coming) how to design a structure that is either transparent, or highlight the edges of any image passing through it.
5/5
5/5