Jacopo Bertolotti

@jacopobertolotti.com

2010 Followers 536 Following

Associated Professor of Physics at the University of Exeter. Maker of typos. Science, scientific visualizations (grouped under the hashtag #PhysicsFactlet), some miniature painting. He/lui/on. All opinions are my own fault.

Miniature of a minotaur wielding a rough mace and a gun (possibly from the "Kill Teams" game?) painted only in shades of blue. Except for one red eye.
"Skinner Out Of Touch" meme with the text: "Should we fine social media for being exploitative?" on top, and "No, it's the kids that need to be put under restrictions" on the bottom.
Two identical miniatures of an orc with a big hammer (from HeroQuest). The left one is very glossy and the colors are blocky. The right one is painted with more shades.
Bloodbowl team of 12 dwarves, painted with white (gray) trousers, purple armour, and copper trims.
Cleric turtleman miniature with a large hammer painted with a blue cloak.
Dragonborn bard miniature painted in a bronze and blue scheme
10 orc miniatures, each painted in a different color.
A orc miniature painted in a contrasting orange and blue scheme. Picture from the front.
Miniature of an orc painted with an orange armour and blue trims.
Tyranid monster from WH40k painted in a purple scheme.
Orc miniature painted with a white armor and bronze trimmings.
Orc miniature painted with a copper armour. In the right hand it holds a big spear with blue reflections.
Orc miniature painted with a nmm black armor.
5 painted orc miniatures, one in red armour, one in blue, one in green, one in pink, and one in yellow. Placed in a line.
Work in progress of an orc miniature painted with a pink and white armour.
Miniature of an orc with a heavy red armor and a large chopper.
Photo of "SideQuested" book 1 and "Aurora" book 2
Painted miniatures of two orcs, one on the left with a bright yellow armour, and one on the right with a dark blue one.
Painted miniature of an orc in a heavy yellow armour with a crude sword and a huge shield
Painted Tyranid prime (from the WH40k starter set).
Simpson meme with Bart on the top saying "none of my presentations tanked the global markets" On the bottom Omer answers "none of your presentations tanked the global markets, yet"
Photo of a detail of the back of a airplane seat. On the corner next to where the safety instructions are, it is written "literature only"
Photo of the old Physics building in Florence. An old-style villa in the middle of the trees.
Coupled dipole simulation the the scattering of a Gaussian beam from a point particle. The image is divided in two rows of three images each. The top row show the electric field (in blue and red), while the bottom row show the modulus squared of the electric field (in green), which is proportional to the intensity. The three columns show the incident field, the scattered field, and the total field.
Simulation of the scattered field from a uniform disk in 2D. In the centre of the screen there is a grey disk, representing the scatterer. On the bottom-right a sinusoidal shows the wavelength of the incident field, while the scattered field is shown in red and blue. The wavelength is made to change periodically between a relatively long and a relatively short one.
Animated gif showing the simulation of a light pulse scattering against a small obstacle. The pulse (green to white on a black background) comes from the bottom, and the scatterer (a white dot) is in the centre. When the pulse hits the scatterer it diffracts.
Picture of an old (and sun-discolored) edition of "The Feynman Lectures on Physics, volume 1" on gray background
Screenshot of the "bluesky map" made by theo.io.
Fake cover of a math textbook by "C. Lou Less" titled "Mathematics for Physicists: Rigour is overrated" (created as a meme)
Measurement of the speckle pattern at the distal end of a multimode fibre as a function of the position of a focussed input. The output speckle is shown as black on a white background, contained in a disk in the centre of the image (the physical extension of the fibre), while the focussed input is shown in red, superimposed with the output picture. As the input moves along a radius, the random-like speckle pattern shows more intensity at the same radius as the input than elsewhere.
Photo of the statue at the entrance of the Jardin des Plantes in Paris. Taken at night, there is a large circular screen behind the statue that illuminates it with ever-chanhing color patterns (at the moment of the picture it was mostly cold blues)
Photoshopped street sign with the silhouette of a fantasy troll monster and the writing "Do not feed the trolls"
A photo of birds sitting on a telephone line onbthe background of a very gray and cloudy sky.
Left panel: a moon-shaped domain in gray over a white background. As time passes more and more orange dots at random positions appear. Right panel: a plot of the estimated area (in orange) as a function of the number of samples. A horizontal purple line shows the "true" value of the area.
Two white curves on a black background. The first is a circular loop, labelled as "A knot". The second is a overhand knot, labelled as "Not a knot".
A initially flat orange surface is gradually deformed. A purple line on top show the shortest curve on the surface between two points.
Animation of the output of a 50um diameter, 20m long fibre (speckle pattern in grayscale), as a function of the input spot radius (red dot)
4 panels with graphs in black and orange on a white background. In the first panel the animation of a simple pendulum with in black the evolution calculated with a high precision method, and in orange the evolution calculated with the Euler method. In the second plot the same thing, but shown in phase space (i.e. plotting the angular velocity against the angle). In the third plot the total energy of the two solutions, with the high precision one (black) staying constant, while the one calculated with the Euler method increasing in steps. Finally, in the fourth panel the formulas used for the two solutions.
3 seconds phone video of the wing of an airplane during landing. A stream of mist (air with droplets of condensed water) is visible coming from the front and curving to follow the shape of the wing.
Plot (black on white) of a relatively complicated function with a red dot showing the current guess of the root. A thin red line is shoot to show the tangent to the point and where it crosses the horizontal axis, which becomes the next best guess.
Plot (black on white) of a relatively complicated function with two red dots at the extreme of the bracketed region and one at the middle point. The function is multiplied by an exponential, and the exponent is adjusted such that the three points are aligned. Then a "false position" step is taken on these three new points and the process starts anew. This converges VERY fast to the root of the function.
Plot of a function that crosses the x-axis at approximately x=1.39. Two red dots show the current bracket, then a line is formed between the two, creating a new point that is used to update the bracket.
Aussi M. Anton Carniaux, directeur des affaires publiques et juridiques de Microsoft France, invité par la commission d’enquête à garantir que les données des citoyens français hébergées par Microsoft ne seront jamais transmises à des autorités étrangères sans l’accord des autorités françaises, a-t-il répondu : « Non, je ne peux pas le garantir ».
Plot of a function that crosses the x axis at roughly x=0.2. The areas for x<-0.5 and for x>0.5 are grayed out to show that we start from a bracket. The midpoint (red dot) is selected and the bracket updated.
Photo of a Commodore 64 showing the "press play on tape" instruction, telling you to turn on the tape reader to load a game/software.
Photoshopped SEM image of a tardigrade playing a violin. Author unknown.
Numerical calculation of the radial and angular part of a optical fibre mode. The electric field intensity is shown as a gradient going from black to green, with overlapping tiny black arrows to show the field orientation. The pattern has a hexagonal symmetry and the arrows appear to swirl around the nodes.
4 plots arranged in a square. In the first 8 data points are shown in red, in the second the points are connected by straight lines, in the third the points are connected by cubic splines, and in the fourth the points are shown to lie on the drawing of an elephant
Photo of a pile of xbox360 games
On the left: incident wavfront represented as a light blue grid of segments that can move back and forward to represent the phase, a scattering medium represented by a grey slab, and the resulting speckle pattern. The segments representing the incident wavefront phase move and the speckle gradually changes from a normal speckle pattern to a single bright spot. On the right: the field at the spot can be seen as the superposition of a large number of random phasors. While the wavefront is optimized the phasors gradually unwind until they are in a straight line.
Drawing of a number of yellow lines (on black background) impinging on five grey ellipsoids representing 5 lenses. After the "lenses" the rays are bent to create one focus per lens. The rays then move, and the foci move with them.
Drawing of two fullerene molecules rotating, with a unit of two hexagon and two pentagons highlighted in red. In the right one, one bond is rotated (Stone-Wales defect)
Image of a partial eclipse of the sun projected with an improvised pinhole camera on a piece of paper.
The wavefunction of a quantum mechanical particle (in orange the wavy real part of the wavefunction and in black its modulus) hits a potential barrier (in red). Classically the particle should 100% reflect, but in quantum mechanics the probability behaves like a wave and so part of the wavefunction is transmitted.
Figure 1 from the paper. A schematic of the setup. Top row: the incoming image (in this case a block letter E) impinges on a metasurface with a transmittance modulus that varies quadratically with the incident angle, resulting in the second derivative of the image, which effectively highlight the edges. Bottom row: if the same input image impinges on the same structure, but in the other phase, the transmittance modulus in angle-independent, and the images passes through without being modified.