Tag: physics
What would happen if a fastball pitcher could throw a baseball at 90% speed of light?
Answering the important questions: What would happen if a fastball pitcher could throw a baseball at 90% speed of light?
Scientists have failed to detect one of the leading theoretical candidates for dark matter.
Null result: Scientists have failed to detect one of the leading theoretical candidates for dark matter.
How the Higgs boson explains the universe.
How the Higgs boson explains the universe.
And what it can’t explain:
The discovery [by the existence of the Higgs boson] that nature is beautifully symmetric means we have very little choice in how the elementary particles do their dance – the rules simply “come for free”. Why the universe should be built in such an elegant fashion is not understood yet, but it leaves us with a sense of awe and wonder that we should be privileged to live in such a place.
Science discovers how the universe operates. Philosophy and religion try to explain why. Thus, it is perfectly reasonable in a rational world to consider the existence of God, and why musings about the possibility of intelligent design do not contradict pure science.
And I speak not as a religious person, but as a secular humanist.
From CERN: The experiments have observed a “particle consistent with long-sought Higgs boson.”
From CERN: The experiments there have now observed a “particle consistent with long-sought Higgs boson.”
The press release also emphasizes repeatedly the preliminary nature of this result. More details in this article, including this not unexpected punchline if you know science:
Already, the new boson seems to be decaying slightly more often into pairs of gamma rays than was predicted by theories, says Bill Murray, a physicist on ATLAS, the other experiment involved in making the discovery.
Brookhaven Labs has achieved the hottest man-made temperature ever, 4 trillion degrees Celsius.
Brookhaven Labs has achieved the hottest man-made temperature ever, 4 trillion degrees Celsius.
In the process, the scientists have found that matter at these temperatures acts more like a liquid than a gas, something they did not expect.
Building a spaceship engine fueled by antimatter.
Building a spaceship engine fueled by antimatter.
Chinese physicists have discovered a key measurement that helps explain why and how can neutrinos magically oscillate between three different states.
Chinese physicists have discovered a key measurement that helps explain why and how neutrinos can magically oscillate between three different states. Moreover, the data
implies that there could be a slight asymmetry between neutrinos and antineutrinos—called CP violation—a slight asymmetry that might help explain why the universe evolved to contain so much matter and so little antimatter.
Pendulum waves
An evening pause:
New results from the Large Hadron Collider suggest that matter and anti-matter really are different.
New results from the Large Hadron Collider suggest that matter and anti-matter really are different.
A fire has damaged Russia’s most productive heavy ion accelerator in Moscow.
More bad news for Russian science: A fire has damaged Russia’s most productive heavy ion accelerator in Moscow.
Five of the biggest unsolved mysteries of physics
CERN announces an update on the search for the Higgs Boson
Not there yet: CERN announces an update on the search for the Higgs Boson.
The main conclusion is that the Standard Model Higgs boson, if it exists, is most likely to have a mass constrained to the range 116-130 GeV by the ATLAS experiment, and 115-127 GeV by CMS. Tantalising hints have been seen by both experiments in this mass region, but these are not yet strong enough to claim a discovery.
Higgs announcement from CERN on December 13
CERN will be making an announcement on the status of its search for the Higgs particle on December 13. From this interview of one of its scientists:
The thing I know for sure is that [CERN Director General] Rolf-Dieter Heuer, who must know the results of both experiments, says that on December 13 we will not have a discovery and we will not have an exclusion.
The inteview is fascinating, as he notes how the Higgs research might also have a bearing on the search for dark matter.
Recent results from the Fermi Gamma-ray Space Telescope have found no evidence of dark matter, a result in some conflict with data obtained from several underground research detectors.
The uncertainty of science: Recent results from the Fermi Gamma-ray Space Telescope have found no evidence of dark matter, a result in some conflict with data obtained from several underground research detectors.
The mystery here is that there is no doubt that something causes the outer objects in galaxies to move faster than expected. Scientists have labeled this something as dark matter, guessing that some undetected and unknown mass exists in the outer reaches of galaxies, thereby increasing the gravity potential and hence the velocity in which objects move.
The problem is that they have yet to identify what that dark matter is.
Multiple dark matter experiments produce multiple results
The uncertainty of science: Multiple dark matter experiments produce multiple results.
A team of Italian scientists have reviewed the earlier faster-than-light neutrino results and have rejected them.
Not so fast: A team of Italian scientists have reviewed the earlier faster-than-light neutrino results and have rejected them.
The hunt for the “God Particle” enters the final stretch
The hunt for the “God Particle” enters the final stretch. And scientists might find it doesn’t exist!
How much does the internet weigh?
An evening pause:
Has dark matter been identified?
From a paper published today on the Los Alamos astro-ph preprint website, scientists suggest that three different physics experiments might have identified dark matter. From the abstract:
Three dark matter direct detection experiments (DAMA/LIBRA, CoGeNT, and CRESST-II) have each reported signals which are not consistent with known backgrounds, but resemble that predicted for a dark matter particle with a mass of roughly ~10 GeV. . . . In this article, we compare the signals of these experiments and discuss whether they can be explained by a single species of dark matter particle, without conflicting with the constraints of other experiments. We find that the spectrum of events reported by CoGeNT and CRESST-II are consistent with each other and with the constraints from CDMS-II, although some tension with xenon-based experiments remains. Similarly, the modulation signals reported by DAMA/LIBRA and CoGeNT appear to be compatible, although the corresponding amplitude of the observed modulations are a factor of at least a few higher than would be naively expected, based on the event spectra reported by CoGeNT and CRESST-II. This apparent discrepancy could potentially be resolved if tidal streams or other non-Maxwellian structures are present in the local distribution of dark matter.
The last sentence above suggests that the differences between the various experiments might be explained by the motion of dark matter itself as it flows through the solar system.
This conclusion is very tentative. The scientists admit that there remain conflicts between the results of the three experiments, and that there also could be explanations other than dark matter for the results. Furthermore, the results of other experiments raise questions about this conclusion.
Nonetheless, it appears that physicists might be closing in on this most ghostlike of all particles in the universe.