Physics

There are multiple conservation laws in nature meaning these are considered to be scientific truths which are fundamental and foundational to all modern science as we know it.

Perhaps the most familiar or common conservation law in science is that of the conservation of energy.
Most models of quantum gravity propose or predict that at very short distances space is a frothing foam where distance and time intervals themselves fluctuate rapidly.  These models predict that if light can travel long distances there will be a cumulative effect due to photons from a source gaining slightly different phases.  The precise nature of the effect, the underlying mechanisms would vary but otherwise they would be probed by the same observation of quasars, the most distant short wavelength light we can observe.

The second infn school of statistics took place this week in the nice "green island" of Ischia, in the gulf of Naples, Italy. Organized by the INFN section of Naples, the school aims at training Ph.D. students and post-graduates in the foundations and the applications of the statistical methods most used nowadays in particle physics, nuclear physics, and astrophysics.

Water behaves in mysterious ways, especially below zero before it turns into ice. Physicists have recently observed the spontaneous first steps of the ice formation process, as tiny crystal clusters as small as 15 molecules start to exhibit the recognizable structural pattern of crystalline ice.

A new study finds that liquid water does not become completely unstable as it becomes supercooled, prior to turning into ice crystals, because of an energy barrier for crystal formation in which supercooled water's compressibility continues to rise. Interestingly, liquid water becomes easier to compress, the colder it gets - unlike other substances, which become harder to compress as temperature drops.


Here is a wordy topic which also happens to be rich with physics and foundational in almost every aspect of engineering.  The 2nd law of thermodynamics states that, you cannot build a device capable of extracting heat from something to do work without having some residual useless heat output.  Perhaps more simply stated, you cannot convert a given amount of heat energy into exactly the same amount of work.  There will always be some frictional type losses that re

Computer simulations have predicted a new phase of matter: atomically thin two-dimensional liquid.


Yesterday I posed a question - Are the first collisions recorded by the LHC running at 13 TeV the highest-energy ever produced by mankind with subatomic particles ? It was a tricky one, as usual, meant to think about the matter.

I received several tentative answer in the comments thread, and thus answered there. I paste the text here as it is of some interest to some of you and I wish it does not go overlooked.

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Dear all, 
The LHC has finally started to produce 13-TeV proton-proton collisions!

The picture below shows one such collision, as recorded by the CMS experiment today. The blue boxes show the energy recorded in the calorimeter, which measures particle energy by "destroying" them as they interact with the dense layers of matter that this device is made up of; the yellow curves show tracks reconstructed by the ionization deposits of charged particles left in the silicon detector layers of the inner tracker. 
A new simulation that explains the collision between clusters of galaxies known as "El Gordo" also challenges popular thinking on the blanket term for undetected 'dark matter'.

In general, galaxy clusters grow in size by merging with each other due to gravitations forces despite the expansion of the universe. El Gordo is the biggest known cluster of galaxies, and is in turn the result of the collision between two large clusters. The simulation believes that the collision process compresses the gas within each cluster to very high temperatures so that it is shining in the X-ray region of the spectrum. In the X-ray spectrum this gas cloud is comet shaped with two long tails stretching between the dense cores of the two clusters of galaxies.
Burton Richter, 1975 Nobel prize in Physics for the discovery of the J/ψ meson, speaks about the need of a new linear collider for the measurement of Higgs boson branching fractions in a video on Facebook (as soon as I understand how to paste here I will!)

Richter has been a fervent advocate of electron-positron machines over hadronic accelerators throughout his life. So you really could not expect anything different from him - but he still does it with all his might. At one point he says, talking of the hadron collider scientists who discovered the Higgs boson: