IceCube's ghost particles and the LHCb decay: two experiments, two kinds of evidence

The newest physics result in this batch is not a discovery claim. It is a very rare decay, seen rarely enough that the word evidence carries the whole story. On 3 November, CERN's LHCb collaboration reported first evidence of a beauty particle decay. The collaboration describes it as predicted once in about 10 billion beauty particles. INFN's release and UK Research and Innovation picked up the result the same morning.

The headline number attached to the search is 42 years, the time physicists have spent hunting this signature. That framing matters more than the particle itself. Several outlets covering the result on 3 November, including a Nacionale piece, put the significance at 3.2 sigma and asked plainly whether this counts as a discovery. It does not, by the usual physics convention. A 3.2 sigma result is evidence, not proof. That difference is the whole point of how the field reports rare events: you publish the excess, you say how big it is, and you wait for more data.

ScienceDaily's write-up on 2 November put the IceCube work in blunter terms.

The University of California San Diego release it draws on describes neutrinos as ghost-like particles that stream through matter almost unhindered. It says the observatory is now detecting extremely high-energy versions arriving from distant cosmic sources. The release compares them with solar neutrinos, which carry roughly 10 billion times less energy. The instrument is a massive detector buried in Antarctic ice. That is the only way to catch particles that mostly pass through everything.

The same release gives useful background on why anyone builds a kilometre-scale detector for this. Neutrinos come in three types: electron, muon and tau. They carry no electric charge. They have mass, but the release says it could be around 10 million times less than an electron's. The exact values and the mechanism that produces them remain unknown. The universe is estimated to hold about 10 to the power 89 neutrinos, roughly a billion for every atom. The weak interaction that occasionally stops one is about 20 orders of magnitude weaker than electromagnetism.

What the ghost particles are for

George Fuller is a distinguished professor of physics at UC San Diego who worked with Francis Halzen on an early IceCube paper. The release quotes him. "Neutrinos are truly ghost-like particles," he said. "It's hard to stop them. It's hard to catch them. How do we even know they exist or where they are?"

The release also notes that Halzen received this year's Nobel Prize in Physics for decisive contributions to IceCube and the discovery of high-energy astrophysical neutrinos. Neutrino work has fed five Nobel Prizes in Physics overall. Separately, a University of Southampton and IIT Kanpur team published a proposal in Physical Review Letters, reported by ScienceDaily on 1 November. The team argues that a long-overlooked heavy neutrino could have temporarily dominated the universe's energy density as it cooled.

The claim is that a particle assumed to interact too weakly to matter could have shaped the conditions that let matter outnumber antimatter. Dr. Rishav Roshan, an author of the study, is quoted saying the particle "has long been dismissed as an irrelevant background detail in particle physics." He says it decays slowly enough to have taken over the energy density after the Big Bang. The group also suggests the scenario could leave gravitational wave signals.

"This decoupled heavy neutrino has long been dismissed as an irrelevant background detail in particle physics."

Experimental work on the fundamentals has been moving too, though on a different scale. A University of Birmingham team, reported by ScienceDaily on 30 October, built a miniature universe from about 24,000 ultracold atoms. The atoms sat a few billionths of a degree above absolute zero, split by two laser beams into a bright observed region and a dark unobserved one. The bright region expanded and contracted repeatedly. The team reported that a form of time emerged from internal changes without an external clock. The paper appeared in Physical Review Research. It is a laboratory analogue of questions usually posed about quantum gravity, not a test of the cosmos itself.

Breaking a textbook limit

On 28 October, ScienceDaily reported a TU Wien and UC San Diego collaboration that pushed X-ray generation past the energy cutoff that standard laser physics predicts. The team fired intense ultraviolet pulses at helium atoms. It found that two electrons interacting together can release energy beyond the single-electron limit. The finding was published in Nature Photonics.

Prof. Tenio Popmintchev of TU Wien described the conventional mechanism in the release. The laser tears one electron from the atom and accelerates it. The light it emits on return carries the energy. Dimitar Popmintchev, a postdoc in the same group, is quoted noting that above the cutoff, frequencies are much weaker. A maximum frequency simply cannot be exceeded.

None of this sits in the same corner of the field as the LHCb result. That is worth saying plainly.

LHCb looks at billions of decays produced at the Large Hadron Collider and counts an excess. IceCube waits for a neutrino to interact in ice. The Birmingham group traps atoms to study time. The TU Wien group fires lasers at helium. The zeptoverse framing spread across outlets on 3 November, from the BBC to the University of Manchester. It describes a scale, not a single experiment.

There is a broader context number worth keeping in view. The Robot Report, writing on 1 November about robotics investment, cited PitchBook figures. Robotics and physical AI startups raised a record $27.6 billion across 1,009 deals in 2025, more than double the prior year. That is not physics, but it is a reminder that capital follows headlines fast. Particle physics results move on a different clock: 42 years of searching for one decay, decades of theory before a detector is built.

Outside the lab, two other stories show how technology companies handle their own commitments. Tom's Hardware reported on 1 November that GOG's business development and partnerships manager, Marcin Paczynski, told GamesRadar+ he would like to sell physical PC games again. Any return would depend on publisher approvals and logistics the storefront has never handled. "Ideally, my dream would be to be able to buy physical versions of those games on GOG," he said, according to that interview.

The same outlet reported on 1 November that Plymouth's police chief, Eric Fadden, ordered staff to disconnect Flock Safety camera power cords. The city cancelled its contract in September and heard nothing back for more than a week. According to The Drive, the council voted unanimously on 22 September. Accounts were suspended the next morning, and a formal cancellation letter went out by mail and email. Fadden's account to The Drive is direct. After more than a week of silence from the company's corporate and legal side, he directed staff to cut the power so the cameras could not record plates.

Back to the physics. The LHCb result will need more data before anyone can call it a discovery. The collaboration's own significance figure, as reported on 3 November, is the number to watch. IceCube's high-energy neutrinos are already detected, but the sources remain unidentified. The heavy neutrino proposal is a calculation awaiting a signal. Each is a step of a different size, and the field is careful about which word it uses for each.