In March 2026, CERN's BASE team loaded 92 antiprotons into a portable trap, drove them about eight kilometres across the CERN site, and kept them stored for more than a month. The trap is a rehearsal for moving antimatter to quieter laboratories.
A separate group reported in October 2026 that it had held a single positron, the electron's antimatter twin, for a month and read out its quantum states. For BASE the prize is sharper comparison of protons and antiprotons: a calmer lab could improve the measurements 100-fold, and any difference would bear on why the universe still has matter.
Why it matters
Antimatter annihilates on contact, so learning to truck it between labs decides whether the sharpest precision tests can ever happen.
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Key Indicators
92
Antiprotons Transported
Particles trapped, driven across CERN's site and unloaded without loss, March 2026
50 sec
Antiproton Coherence Time
First coherent quantum transition observed in a free antimatter particle
100x
Precision Improvement Sought
Target gain from measuring antiprotons in a magnetically quieter laboratory
1.6 ppb
Antiproton Magnetic Moment Precision
Fractional accuracy BASE reports for the antiproton; the proton figure is 0.3 ppb
1:1,000,000,000
Matter Survival Rate
Ratio of matter that survived Big Bang annihilation, the mystery driving this research
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16 events
Latest: October 2026
Showing 8 of 16
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October 2026
Single Positron Held for a Month
LatestMeasurement
A Northwestern University group led by Gerald Gabrielse loads one positron into a trap, cools its cyclotron motion to the quantum ground state and holds it for a month, resolving individual quantum jumps. The demonstration does not yet yield a high-precision measurement of the positron.
September 2026
Antiproton Transport Study Published in Nature
Publication
BASE publishes its peer-reviewed report on the March road transport and month-long storage of antiprotons. The authors say the work was a transport demonstration, not a new proton–antiproton comparison.
March 2026
92 Antiprotons Driven Across CERN
Breakthrough
BASE loads 92 antiprotons into BASE-STEP, drives the trap around CERN's main site for roughly half an hour, and unloads it without losing a particle. The team kept the antiprotons for more than a month at a vacuum better than 2.2×10⁻¹⁸ millibar. One antiproton annihilated on day 27 during a particle-extraction test.
July 2025
First Antimatter Qubit Created
Breakthrough
BASE maintains single antiproton in coherent quantum superposition for 50 seconds, published in Nature. First coherent spectroscopy of free antimatter particle.
October 2024
Protons Moved Across CERN in a Portable Trap
Technique
BASE loads its transportable trap, BASE-STEP, with protons and drives it across CERN's main site as a rehearsal for moving antiprotons. The work was published in Nature in May 2025.
August 2024
Rapid Cooling Method Developed
Technique
BASE develops trap reducing antiproton cooling time from 15 hours to 8 minutes for faster, more precise measurements.
September 2023
Antimatter Falls Down
Measurement
ALPHA-g collaboration publishes Nature paper showing antihydrogen falls under gravity like matter, ruling out repulsion theory.
2021
Sympathetic Cooling Breakthrough
Technique
BASE demonstrates sympathetic cooling of protons, recognized as Physics World Top 10 Breakthrough of the Year.
October 2017
BASE Breaks Its Own Antiproton Record
Measurement
BASE reports a sharper measurement of the antiproton magnetic moment, breaking its own precision record for the particle, according to CERN.
August 2015
Most Precise CPT Test in Baryon Sector
Measurement
BASE publishes antiproton-to-proton charge-to-mass ratio measurement in Nature at 69 parts per trillion precision.
June 2014
BASE Measures Proton Magnetic Moment
Measurement
BASE collaboration achieves first direct high-precision proton measurement at 3.3 parts per billion fractional precision.
CERN Council approves conversion of antiproton collector into dedicated antimatter factory.
1967
Sakharov Conditions Published
Theoretical
Andrei Sakharov proposes three conditions necessary to explain matter-antimatter asymmetry, launching baryogenesis field.
August 1932
First Antimatter Discovered
Experimental
Carl Anderson observes positron tracks in cloud chamber, confirming Dirac's prediction. Wins Nobel Prize in 1936.
January 1928
Dirac Predicts Antimatter
Theoretical
Paul Dirac's equation combining quantum theory and relativity predicts existence of antiparticles with opposite charge.
Scenarios
1
Asymmetry Found, New Physics Discovered
Possible
Discussed by: Theoretical physicists and BASE collaboration researchers
Improved precision measurements reveal tiny but definitive differences between proton and antiproton properties, violating CPT symmetry. This would require new physics beyond the Standard Model and could explain why matter survived the Big Bang. The discovery would trigger massive theoretical and experimental efforts to understand the mechanism, potentially involving new particles or forces. Nobel Prize territory.
2
Perfect Symmetry Confirmed, Puzzle Deepens
Likely
Discussed by: Mainstream physics community consensus
Even at 100x improved precision, protons and antiprotons remain identical within measurement uncertainty. CPT symmetry holds firm. This pushes the mystery elsewhere—perhaps to rare decay processes, neutrino physics, or conditions during cosmic inflation that aren't accessible through laboratory antimatter experiments. Research continues but the explanation remains elusive.
The antimatter qubit technique finds unexpected applications in ultra-precise timekeeping and fundamental constant measurements. While not solving the matter-antimatter puzzle directly, the technology enables new tests of physics at unprecedented precision levels. Other antimatter experiments adopt coherent spectroscopy methods, accelerating the field. Think atomic clocks, but for testing reality's edge cases.
4
Antiprotons Arrive in Düsseldorf
Possible
Resolves by End of 2028
Discussed by: BASE collaboration, Heinrich Heine University Düsseldorf
BASE makes BASE-STEP autonomous enough for a roughly ten-hour road journey from Geneva to a precision laboratory at HHU, then transfers the antiprotons into a separate trap without losing them. Success turns the transport test into a working supply line for measurements at lower magnetic noise.
Historical Context
3 moments from history that rhyme with this story — and how they unfolded.
1 of 3
1964-1980
Discovery of CP Violation (1964)
James Cronin and Val Fitch discovered that neutral kaons decay differently than their antimatter counterparts, violating charge-parity symmetry. This was the first experimental proof that nature's laws treat matter and antimatter differently. The discovery earned them the 1980 Nobel Prize and showed that asymmetry between matter and antimatter exists in nature.
Then
Shocked the physics community and validated the possibility that matter-antimatter asymmetry could be explained by fundamental laws, not just initial conditions.
Now
Became a cornerstone of modern cosmology, but the observed CP violation is far too small to explain the universe's matter dominance, driving searches for additional sources.
Why this matters now
BASE's precision measurements search for CP and CPT violations in baryons that could provide the missing explanation for why we exist.
2 of 3
1960s-2012
Higgs Boson Discovery (2012)
Peter Higgs and others predicted a field giving particles mass in the 1960s. CERN's Large Hadron Collider found the Higgs boson in 2012 after a decades-long search requiring unprecedented detector precision and data analysis. The discovery confirmed the Standard Model's final missing piece, earned Higgs and François Englert the 2013 Nobel Prize.
Then
Validated the Standard Model and demonstrated that massive, coordinated experiments can find predicted particles decades after theorists propose them.
Now
Completed the Standard Model but highlighted what it can't explain—including matter-antimatter asymmetry, dark matter, and dark energy.
Why this matters now
Like the Higgs search, BASE pursues a decades-long precision measurement program to test theoretical predictions. But where Higgs validated the Standard Model, BASE might break it.
3 of 3
1995-2025
Trapped Ion Quantum Computing (1990s-present)
Researchers developed techniques to trap individual ions with electromagnetic fields and manipulate their quantum states, achieving coherence times extending to hours. These systems became leading candidates for quantum computers due to their stability and precision control. Current record coherence times exceed 5,500 seconds for ytterbium ions.
Then
Demonstrated that quantum states can be maintained far longer than initially thought possible with proper isolation and control.
Now
Enabled both quantum computing development and ultra-precise measurements of fundamental physics, with trapped ion techniques now standard in metrology.
Why this matters now
BASE adapted trapped ion techniques for antiprotons, using Penning traps to create the antimatter qubit. The 50-second coherence time proves antimatter can be controlled with similar quantum precision.
