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Chalmers examines collisions within CERN's showpiece particle smasher, the Large Hadron Collider. The two "bumps" have appeared independently, in the same place, in the latest data from the LHC's two big detectors, ATLAS and CMS. They point to the existence of a particle that dwarfs even the Higgs boson, the giver-of-mass particle discovered at CERN in Jul 2012. The latest LHC bumps were spotted in collisions that produce two high-energy photons of light. Such collisions should generally produce fewer very energetic photons, purely because these take more energy to make.

A hunt for one of nature's most elusive processes could reveal why matter dominates our universe, finds Matthew Chalmers

The microscopic world seems to be a confusingly random and uncertain place – but that might be because we ourselves are uncertain about the world

An attempt to make our most successful theory of nature more real seems to imply the existence of a monstrous entity pulling reality's strings

The elusive explanation of one of reality's greatest mysteries could lie in physics we already know

The discovery of the Higgs boson completed the most precise scientific model in history – and that's where the problems start, says Matthew Chalmers

If the particle discovered at CERN this July is all we think it is, there are good reasons to want it to be something else

Physicists are planning the powerful accelerators they will need to study the Higgs boson and its interactions in detail.

The Tevatron particle smasher has seen yet another glimpse of revolutionary new physics in its dying days. This one could be for real.

Experiments on atoms cooled to within a whisker of absolute zero could provide a new window on the cosmos's darkest secrets

If a branch of physics were to be judged by the number of Nobel laureates it has produced, then superfluidity would surely rank among the most successful. The field has borne nearly 20 laureates, from the award of the 1913 Nobel Prize for Physics to Heike Kamerlingh Onnes, who discovered superconductivity, to that of the 2003 prize to Alexei Abrikosov, Vitaly Ginzburg and Tony Leggett for their contributions to the theory of superconductors and superfluids. The reason why is simple: these counterintuitive phenomena, whereby below a certain temperature matter flows without resistance, are rare examples of quantum-mechanical behaviour seen at the macroscopic scale.

It is intriguing to note that modern science began shortly after the invention of the printing press. When Nicolas Copernicus presented his heliocentric and heretical view of the universe in 1543, he was only able to do so, claim some historians, because he had access to a diverse range of printed sources that enabled him to compare and contrast older ideas. Such materials are also said to have allowed Tycho Brahe, Johannes Kepler and others to pick up where Copernicus left off, free of prejudice and armed with precise mathematical tables that would prove vital in driving the scientific revolution forward.

If you are an academic in a physics department, you are probably used to receiving letters from people who claim to have rewritten the laws of physics. Editors of science magazines are also familiar with such individuals, many of whom take gravity for their victim. Although we should not automatically dismiss these ideas – after all, Einstein was an unknown patent clerk when he rocked the world of physics in 1905 – most fall down because their proponents fail to put them in context with existing knowledge.

The atom clocks that supply the heartbeat of modern life have become so accurate that they are exposing the elusive nature of time itself

Exotic subatomic particle confirmed at Large Hadron Collider after earlier false sightings.

It's crunch time for the International Linear Collider as particle physicists eye up circular alternatives, as Matthew Chalmers reports.

The 62nd Lindau Nobel Laureate Meeting opened with a talk by Brian Schmidt, who shared the 2011 physics prize for the shocking revelation that the Universe is expanding at an accelerating rate. Fifteen years after Schmidt's initial discovery, the 'dark energy' invoked to explain this cosmic acceleration is still a mystery.

Physicists hoping for signs of radically new particles get no joy from Large Hadron Collider.

This year's Lindau meeting coincided with the biggest particle-physics discovery in a generation. Theoretical particle physicist Martinus Veltman, emeritus professor at the University of Michigan in Ann Arbor, shared the 1999 Nobel Prize in Physics for his work on the 'standard model' of particle physics — the theory that predicted the Higgs boson. Yet he has spent the past 30 years doubting whether the Higgs exists.

An elegant theory that promises to take physicists beyond the confines of the Standard Model of particle physics faces its final test.

Cast your mind back to the summer of 2008, when speculation about potential discoveries at CERN's Large Hadron Collider (LHC), which was then about to switch on, went into overdrive.

We ask Edward Witten, leading architect of string theory, how it feels to work in an area where it's a problem telling other people what he's up to

Most physicists would be happy to make one discovery that is important enough to be taught to future generations of physics students. Only a very small number manage this in their lifetime, and even fewer make two appearances in the textbooks. But Einstein was different. In little more than eight months in 1905 he completed five papers that would change the world for ever. Spanning three quite distinct topics – relativity, the photoelectric effect and Brownian motion – Einstein overturned our view of space and time, showed that it is insufficient to describe light purely as a wave, and laid the foundations for the discovery of atoms.

Physics and biology are becoming better acquainted all the time. With quantum dots at the forefront of medical imaging and DNA set to revolutionize nanotechnology, the two disciplines are also proving to be an excellent match. Now physics and biology have met in the rather stark setting of a steel broom cupboard in an electronics lab. Martin Robinson, Darren Stone and Janet Clegg at York University in the UK have used a novel electromagnetic technique to measure changes in the body's water content. Their method is fast, accurate and cheap, and is now attracting interest from hospitals to help monitor diseases that affect patients' water levels (M P Robinson et al. 2003 Phys. Med. Biol. 48 113–125).

CERN's discovery of a new fundamental particle – most likely a Higgs boson – was barely hours old when physicists at the annual Lindau Nobel Laureate Meeting in Germany called for a new facility to measure its properties in detail. Leading the cry was former CERN boss Carlo Rubbia, who shared the 1984 Nobel Prize for Physics for the discovery of W and Z bosons.

Particle physicists are honing in on the Higgs boson after last month presenting the latest results from CERN's Large Hadron Collider (LHC).

Apart from being huge, complex and expensive, CERN's Large Hadron Collider (LHC) is perhaps most famous for having broken down just nine days after it was switched on in September 2008. Some 14 months and more than €27m worth of repairs later, the LHC sprang spectacularly back to life late last year as jubilant physicists collided particles at record-breaking energies. But to reduce the chances of the LHC being derailed again by a similar accident, physicists at the Geneva lab have decided to run the collider at just half its design energy for the next 18–24 months.

The European Physical Society (EPS) has defended its handling of the 2009 prize for high-energy and particle physics despite complaints that the awarding committee overlooked a vital scientific contribution to the prize-winning work. The biennial award, worth SwFr 5000, was given to collaborators on the Gargamelle bubble-chamber experiment at CERN for their discovery in 1973 of the "weak neutral current" – one of the ways in which the weak nuclear force is mediated between fundamental particles. However, the award did not formally recognize the "leptonic" evidence for neutral currents, without which some particle physicists say the discovery could not have been made.

After nigh-on three decades, scientists at the CERN laboratory near Geneva are on the verge of completing the world's most powerful particle collider. With all of the 1600 superconducting magnets that will be used to guide protons around the Large Hadron Collider (LHC) having been cooled to 1.9 K, the machine is finally ready to start circulating the first proton beams around its 27 km circumference underground ring.

Exotic particles called axions coming from the sun could be detected by a satellite hiding behind Earth

Particle physicists in the UK are fighting to stave off funding cuts that could diminish their role in two of the four experiments at the Large Hadron Collider (LHC) at CERN. The physicists are members of the LHCb and ALICE experiments, which were rated as "medium lower" and "lower" priority, respectively, in a review carried out earlier this year by the UK's Science and Technology Facilities Council (STFC). They claim that the poor ranking could even jeopardize the operation of the detectors.

The KEK laboratory in Japan has unveiled an ambitious five-year plan that includes a major upgrade to its flagship "B-factory" and a strong commitment to the proposed International Linear Collider (ILC). The plan, outlined in a road map published last month, is good news for particle physicists following the US's decision to slash funds for the ILC (see p7) and the UK pulling out from the collider completely (Physics World January p7). "This report demonstrates the sustained commitment to high-energy physics of the Japanese, who, of course, are one of the leading contenders to host the ILC," says Brian Foster of Oxford University in the UK and European director of the collider's global design effort.

After months of painstaking analysis, the Wilkinson Microwave Anisotropy Probe (WMAP) team has released its latest view of the radiation left over from the Big Bang. The results provide the first-ever map of the polarization of the cosmic microwave background, revealing the universe when it was just 10–35 s old and putting the standard cosmological model through its toughest test to date.

An experiment in the US has cast fresh doubt about the existence of pentaquarks, particles containing five quarks. The CLAS collaboration at the Jefferson Laboratory in Virginia, US, said in 2003 that it had evidence for the θ+(1540) (where 1540 is the mass of the particle in MeV). But it has since generated additional data and that evidence has now disappeared. Although the experiment cannot completely rule out the existence of pentaquarks, the result adds to an increasing number of negative searches for such particles in recent months.

Physics in the 20th century was built on two great revolutions: the general theory of relativity and quantum mechanics. These two theories have profoundly changed the way we think about space, time and the meaning of reality, and both have been verified to extraordinary precision. However, the two theories are also completely incompatible with one another.