First principles
What has changed at the level of science or engineering—and why is it possible now?
EARLY-STAGE INVESTOR · PARTICLE PHYSICIST
Hey, I’m Ran Chen.
Where frontier technology
meets real-world industry.
I invest in early-stage frontier technology at FreeS Fund, drawing on a scientist’s instinct for first principles, hard questions, and faint signals.
寻找前沿科技走向产业的交汇处
A DIFFERENT WAY TO SEE
THE SUN, IN NEUTRINOSThis map is built from neutrinos born in fusion reactions at the Sun’s core. Its brighter pixels show the directions where Super-Kamiokande collected more neutrino signals over time.
≈ 8 minNeutrinos travel almost straight out of the Sun and reach Earth. The light energy made in the core can take tens of thousands of years to work its way to the surface.
I look at frontier technology the same way: notice the faint signal early, then follow it toward the real world.
How Super-Kamiokande sees the SunCONNECTINGScienceTechnologyFoundersIndustry
EARLY-STAGE INVESTING · FREES FUND
From scientific possibility
to industrial reality.
I look for frontier technologies with the potential to leave the lab, enter the world, and reshape how an industry works.
About FreeS FundMY INVESTMENT LENS
Industry pull
Which real constraint does the technology remove, and who cares enough to adopt it?
Founder insight
What does this team understand before the rest of the market sees it?
ONE CURIOSITY, TWO WORLDS
Following faint signals—
from physics
to companies.
I’m an early-stage investor at FreeS Fund and a particle physicist by training.
My research taught me how to reason from first principles, work at the edge of what is measurable, and stay patient when evidence is scarce. Investing gives me a new way to apply that mindset: finding technical breakthroughs that can become meaningful companies.
I’m most interested in the moment when frontier science begins to answer an urgent industrial need.
My particle physics journey
From 2019 through August 2025, I worked in experimental particle physics at Northwestern University, studying two of the universe’s most elusive subjects—dark matter and neutrinos. Think of me as a cosmic detective: using cryogenic detectors, rare-event search techniques, and a healthy dose of caffeine to look for particles that rarely leave a trace.
Under the guidance of my advisor, Enectalí Figueroa-Feliciano, and alongside brilliant collaborators, I’ve developed a diverse skill set, from building theoretical models to developing software pipelines that make sense of endless data streams. Python and C++ are basically my second and third languages, and I’ve used them to optimize simulations and hunt for particle-shaped needles in cosmic haystacks. I’ve even had the honor of presenting my findings at international conferences, proving that particle physics isn’t just a lab job—it’s a global effort where everyone is equally baffled but incredibly determined.
That chapter of experimental work ended in August 2025, but its habits remain central to how I think: test assumptions, respect the evidence, and stay curious when the signal is faint. I now bring that mindset to early-stage technology investing.
EXPERIMENTS & COLLABORATIONS
Small signals. Big questions.
Experimental work completed in August 2025.
NEUTRINOS2020 — Aug 2025
Ricochet
My work focused on measuring coherent elastic neutrino–nucleus scattering (CEνNS) at a nuclear reactor, using cryogenic detectors sensitive to the smallest recoils.
Explore the experimentDARK MATTER2019 — Aug 2025
SuperCDMS
I searched for dark matter particles lighter than ten proton masses. A tiny signal could open a window into an entirely new world of particles.
Explore the experimentFROM QUESTIONS TO PAPERS
Selected publications
Selected work, explained in plain language.
Constraints on low-mass, relic dark matter candidates from a surface-operated SuperCDMS single-charge sensitive detectorThis study used a highly sensitive SuperCDMS detector to look for the tiny energy deposits expected from lightweight dark matter. Operating above ground made background noise especially challenging. The result ruled out new regions where these particles could have been hiding.DARK MATTER
Light dark matter search with a high-resolution athermal phonon detector operated above groundThis search listened for minute vibrations, called phonons, that a dark matter particle might create inside a crystal. The detector could resolve extraordinarily small amounts of energy. Finding no clear signal helped narrow the range of possible dark matter properties.DARK MATTER
EXCESS workshop: Descriptions of rising low-energy spectraSeveral highly sensitive experiments have seen an unexpected rise in events at their lowest measured energies. This workshop brought those observations together and compared how they look across different detectors. Mapping their similarities helps determine whether they come from new physics or overlooked backgrounds.LOW-ENERGY SIGNALS
Coherent elastic neutrino-nucleus scattering: Terrestrial and astrophysical applicationsNeutrinos can strike an entire atomic nucleus at once, producing a tiny but measurable recoil. This review explains that process and surveys what it can reveal about particle physics, nuclear reactors, stars, and supernovae. It connects a subtle laboratory signal to questions across the universe.NEUTRINOS
Search for low-mass dark matter via bremsstrahlung radiation and the Migdal effect in SuperCDMSLightweight dark matter may be too subtle to observe through a direct collision alone. This study searched for extra radiation or displaced electrons produced during an atomic interaction—the bremsstrahlung and Migdal effects. These secondary signals open additional ways to detect otherwise invisible particles.DARK MATTER
Design and characterization of a phonon-mediated cryogenic particle detector with an eV-scale threshold and 100 keV-scale dynamic rangeRare-particle searches need detectors that notice extremely small energy deposits without losing track of larger events. This work designed and tested a cryogenic detector with an electron-volt-scale threshold and a broad measurement range. The result is a versatile instrument for future dark matter and neutrino experiments.DETECTOR DESIGN
SHARING THE SCIENCE
Talks & presentations
Let’s compare notes.