Category: pilot wave

Two months ago, FYPhysics! in collaboration with FYFD on Tumblr dedicated an entire series exploring Pilot wave hydrodynamics. (You can check it out here)

And from one of the posts we learned that when you blow air through a nozzle at a water surface, you can see a circular wave propagating outwards.

BUT when a vibrational excitation is given to this propagating wave, that wave is split into two traveling waves moving in opposite directions – One towards the source ( called time-reversed waves ) and one away from it.

Now this paper by Bacot ,et.al takes this to the next level by positioning these nozzles in the shape of an Eiffel tower.

Now when one changes the effective gravity through a vibration, the time-reversed waves refocus at the center giving us back the Eiffel tower structure.

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The group was also successful in refocusing a smiley face using the same principles which is equally mind blowing. (You can watch the video here)

Have a great week

The Biggest Myth In Quantum Physics

“Questions like “How or why does [quantum physics] work?” or “What, if anything, do the mathematical objects in [quantum] theory represent?” have as many answers as we care to give them. But those, arguably, say much more about us and our prejudices, biases, and assumptions about the Universe than the reality of the Universe itself. There are very few things we can actually observe in nature: particle properties like position, momentum, cross-sections, scattering amplitudes, and individual quantum states are pretty much it. Asking questions about the underlying nature of reality assumes that a true reality conforms to certain rules that fit our intuition, while the exact opposite may turn out to be true. Our perception of reality is determined by our limited senses and capabilities, and whatever rules truly govern the Universe may be more foreign to us than our minds have ever conceived of.”

Quantum physics is one of the strangest beasts we’ve ever stumbled upon when it comes to the nature of the Universe. We may be used to physical objects with well-defined properties in our everyday reality, but at the quantum level, the Universe is full of unexpected surprises. On very small scales, objects act as both waves and particles, depending on what you do to them. They have interactions that are non-local, tied to one another across large spans in both space and time. They don’t have well-defined properties until you measure them, and that’s perhaps the spookiest thing of all. Yet there’s one thing we’ve done in recent years that may be the worst crime of all: we’ve assigned interpretations to quantum physics in an attempt to better describe reality. Only, we haven’t learned anything about reality at all; all we’ve done is insert ourselves and our prejudices, biases, and our useless intuition into quantum physics.

The result has been the perpetuation of the biggest myth in quantum physics: that it needs an interpretation at all.

“If you place a small droplet atop a vibrating pool, it will happily bounce like a kid on a trampoline”. And when lots of these droplets are placed in a lattice, their behavior as a collective is absolutely fascinating.

In this series of gifs, you can see the evolution of complex lattices from simple droplets eventually leading to an instability that drives them apart.

Now a key thing to note is that when you have 7 droplets, you will not obtain a hexagonal lattice configuration per se. Those lattices had to be obtained artificially but can be very stable after they are formed.

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Source: Archimedean lattices in the bound states of wave interacting particles

The key point of distinction when one talks about lattice in this vernacular is that in solid state physics, a crystal lattice is the depiction of three-dimensional solid as points.

And one obtains these crystalline solids through crystallization.

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In contrast, when we are talking about lattices in pilot wave hydrodynamics, they are formed by the standing waves of the bouncing droplets.

In the upcoming posts, we will take a dive into some quantum mechanical experiments and their pilot wave hydrodynamic counterparts.

In case you had missed out, here are the previous posts on this collaborative series on Pilot wave Hydrodynamics with FYFD : 1) Introduction; 2) Chladni patterns; 3) Faraday instability, 4) Bouncing droplets

Pilot Wave Hydrodynamics – A Tumblr series

Next week, FYP! in collaboration with FYFD is bringing you an exclusive Tumblr series on Pilot wave hydrodynamics. There will be a new post on FYP! and FYFD all through next week (Jan 8 – 12) exploring pilot wave hydrodynamics.

This has been the topic of spectacular experimental investigations and revelations (and controversies too) in Fluid Dynamics & Quantum Mechanics in recent times.

On Monday, we begin this journey in the labs of Michael Faraday and Chladni; And then embark on an exciting adventure through decades of research to arrive at where we are today.

Stay Tuned!