Episode notes
How do engineers solve problems that seem to violate the laws of physics? In this episode, we speak with Dan Gelbart, a prolific inventor and precision engineer, about what it really means to work at the limits of physical law. From lasers and optical systems to ultra-precision manufacturing and semiconductor tools, Gelbart has spent decades designing systems where nanometers, noise, and nonlinearities matter, and where small misunderstandings of physics can block real progress. We discuss the story of the first working laser, built by Theodore Maiman, and why it succeeded only after…
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632nm
Misha Shalaginov, Michael Dubrovsky, Xinghui Yin · Tech & Science · English
Technical interviews with the greatest scientists in the world.
More from 632nm All episodes →
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E53 · 5 May 2026 · 2 hr 1 min
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How do you measure something as small as a single electron or map quantum behavior at the nanoscale? In this episode, Misha spoke with Amir Yacoby, professor at Harvard University, about the cutting edge of quantum sensing and the experimental tools redefining how we probe the quantum world. Yacoby explains how physicists build ultra-sensitive detectors, from single-electron transistors to quantum dots and NV centers in diamond, that can measure charge, spin, and magnetic fields with extraordinary precision. These tools make it possible to study both strongly correlated systems, like those…
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E52 · 21 Apr 2026 · 1 hr 14 min
The Physics of Un-Hackable Face Recognition | Rob Devlin on Metalenz
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E51 · 1 Apr 2026 · 1 hr 38 min
The Real Economics of Data Centers in Space | Starcloud CEO Philip Johnston
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E50 · 27 Mar 2026 · 2 hr 4 min
How To Make Quantum Algorithms Cheaper | Craig Gidney on Magic-State Factories, Resource Estimates
How do you actually make quantum algorithms work on real hardware? Build your own quantum circuits in Crumble: https://algassert.com/crumble In this episode, we speak with Craig Gidney of Google Quantum AI, whose work focuses on the practical realities of building fault-tolerant quantum computers. Gidney explains how seemingly small implementation choices, like how you perform arithmetic, can dominate the cost of entire quantum algorithms. We explore why factoring small numbers like 15 in Shor's algorithm can be misleadingly easy, and why scaling to larger numbers requires dramatically more…
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E49 · 10 Mar 2026 · 1 hr 30 min
How Neurons Translate Electricity into Chemistry | Tom Südhof
How do neurons convert electrical signals into chemical messages in under a millisecond? In this episode, we speak with Thomas Südhof, Stanford neuroscientist and Nobel laureate whose discoveries revealed the molecular machinery that allows neurons to communicate at synapses. Südhof explains how an electrical impulse traveling down a neuron triggers the rapid release of neurotransmitters, transforming an electrical signal into a chemical one that can be received by the next cell. We explore the remarkable precision of synaptic transmission, including how calcium ions trigger vesicle fusion,…
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E47 · 3 Feb 2026 · 1 hr 56 min
How Visual Experience Rewires the Brain | Mark Bear on Neuroplasticity
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E46 · 20 Jan 2026 · 2 hr 13 min
Snell's Law, Metasurfaces, and Metalenses | Federico Capasso
How can flat surfaces shape light as powerfully as bulky lenses? In this episode, we speak with Federico Capasso, Harvard physicist and pioneer of metasurfaces, metalenses, and nanophotonics. Capasso traces the path from his work at Bell Labs on quantum cascade lasers to the invention of metasurface optics, showing how a practical challenge—collimating light without traditional lenses—sparked a new way to control light. We explore the physics behind metasurfaces and generalized Snell’s law, explaining how subwavelength structures enable precise control of wavefronts, phase, and polarization…
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E45 · 6 Jan 2026 · 2 hr 47 min
Graphene, Nanotubes, and Quantum Hall Physics | Philip Kim
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E44 · 23 Dec 2025 · 2 hr 35 min
Quantum Matter, Super-conductors, and Black Holes | Subir Sachdev on the SYK Model
What makes high-temperature superconductors and “strange metals” some of the most perplexing systems in modern physics? In this episode, we speak with Dr. Subir Sachdev: Harvard physicist and one of the leading architects of today’s understanding of quantum matter. Sachdev explains why strange metals refuse to behave like ordinary conductors, how quantum entanglement reshapes the landscape of many-body physics, and why the quest to understand cuprate superconductors continues to push both theory and experiment to their limits. We explore the physics of the cuprate phase diagram, the collapse…
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E43 · 9 Dec 2025 · 1 hr 50 min
How to Build Fault-Tolerant Quantum Computers | Austin Fowler on Surface Codes + TQEC
Would we get a quantum computer sooner if everything was open source? In this episode, we speak with Austin Fowler, one of the architects of quantum error correction and a pioneer of the surface code used in today’s leading quantum computers. Fowler helped lay the groundwork for scalable, fault-tolerant computation at Google Quantum AI, before leaving to advocate for a more open and collaborative model of research. He explains why building a useful quantum computer will require millions of reliable qubits, why no known algorithm yet clearly outperforms classical computation, and why the…
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